1 /* 2 ** 2001-09-15 3 ** 4 ** The author disclaims copyright to this source code. In place of 5 ** a legal notice, here is a blessing: 6 ** 7 ** May you do good and not evil. 8 ** May you find forgiveness for yourself and forgive others. 9 ** May you share freely, never taking more than you give. 10 ** 11 ************************************************************************* 12 ** This header file defines the interface that the SQLite library 13 ** presents to client programs. If a C-function, structure, datatype, 14 ** or constant definition does not appear in this file, then it is 15 ** not a published API of SQLite, is subject to change without 16 ** notice, and should not be referenced by programs that use SQLite. 17 ** 18 ** Some of the definitions that are in this file are marked as 19 ** "experimental". Experimental interfaces are normally new 20 ** features recently added to SQLite. We do not anticipate changes 21 ** to experimental interfaces but reserve the right to make minor changes 22 ** if experience from use "in the wild" suggest such changes are prudent. 23 ** 24 ** The official C-language API documentation for SQLite is derived 25 ** from comments in this file. This file is the authoritative source 26 ** on how SQLite interfaces are supposed to operate. 27 ** 28 ** The name of this file under configuration management is "sqlite.h.in". 29 ** The makefile makes some minor changes to this file (such as inserting 30 ** the version number) and changes its name to "sqlite3.h" as 31 ** part of the build process. 32 */ 33 #ifndef SQLITE3_H 34 #define SQLITE3_H 35 #include <stdarg.h> /* Needed for the definition of va_list */ 36 37 /* 38 ** Make sure we can call this stuff from C++. 39 */ 40 #ifdef __cplusplus 41 extern "C" { 42 #endif 43 44 45 /* 46 ** Facilitate override of interface linkage and calling conventions. 47 ** Be aware that these macros may not be used within this particular 48 ** translation of the amalgamation and its associated header file. 49 ** 50 ** The SQLITE_EXTERN and SQLITE_API macros are used to instruct the 51 ** compiler that the target identifier should have external linkage. 52 ** 53 ** The SQLITE_CDECL macro is used to set the calling convention for 54 ** public functions that accept a variable number of arguments. 55 ** 56 ** The SQLITE_APICALL macro is used to set the calling convention for 57 ** public functions that accept a fixed number of arguments. 58 ** 59 ** The SQLITE_STDCALL macro is no longer used and is now deprecated. 60 ** 61 ** The SQLITE_CALLBACK macro is used to set the calling convention for 62 ** function pointers. 63 ** 64 ** The SQLITE_SYSAPI macro is used to set the calling convention for 65 ** functions provided by the operating system. 66 ** 67 ** Currently, the SQLITE_CDECL, SQLITE_APICALL, SQLITE_CALLBACK, and 68 ** SQLITE_SYSAPI macros are used only when building for environments 69 ** that require non-default calling conventions. 70 */ 71 #ifndef SQLITE_EXTERN 72 # define SQLITE_EXTERN extern 73 #endif 74 #ifndef SQLITE_API 75 # define SQLITE_API 76 #endif 77 #ifndef SQLITE_CDECL 78 # define SQLITE_CDECL 79 #endif 80 #ifndef SQLITE_APICALL 81 # define SQLITE_APICALL 82 #endif 83 #ifndef SQLITE_STDCALL 84 # define SQLITE_STDCALL SQLITE_APICALL 85 #endif 86 #ifndef SQLITE_CALLBACK 87 # define SQLITE_CALLBACK 88 #endif 89 #ifndef SQLITE_SYSAPI 90 # define SQLITE_SYSAPI 91 #endif 92 93 /* 94 ** These no-op macros are used in front of interfaces to mark those 95 ** interfaces as either deprecated or experimental. New applications 96 ** should not use deprecated interfaces - they are supported for backwards 97 ** compatibility only. Application writers should be aware that 98 ** experimental interfaces are subject to change in point releases. 99 ** 100 ** These macros used to resolve to various kinds of compiler magic that 101 ** would generate warning messages when they were used. But that 102 ** compiler magic ended up generating such a flurry of bug reports 103 ** that we have taken it all out and gone back to using simple 104 ** noop macros. 105 */ 106 #define SQLITE_DEPRECATED 107 #define SQLITE_EXPERIMENTAL 108 109 /* 110 ** Ensure these symbols were not defined by some previous header file. 111 */ 112 #ifdef SQLITE_VERSION 113 # undef SQLITE_VERSION 114 #endif 115 #ifdef SQLITE_VERSION_NUMBER 116 # undef SQLITE_VERSION_NUMBER 117 #endif 118 119 /* 120 ** CAPI3REF: Compile-Time Library Version Numbers 121 ** 122 ** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header 123 ** evaluates to a string literal that is the SQLite version in the 124 ** format "X.Y.Z" where X is the major version number (always 3 for 125 ** SQLite3) and Y is the minor version number and Z is the release number.)^ 126 ** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer 127 ** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same 128 ** numbers used in [SQLITE_VERSION].)^ 129 ** The SQLITE_VERSION_NUMBER for any given release of SQLite will also 130 ** be larger than the release from which it is derived. Either Y will 131 ** be held constant and Z will be incremented or else Y will be incremented 132 ** and Z will be reset to zero. 133 ** 134 ** Since [version 3.6.18] ([dateof:3.6.18]), 135 ** SQLite source code has been stored in the 136 ** <a href="http://fossil-scm.org/">Fossil configuration management 137 ** system</a>. ^The SQLITE_SOURCE_ID macro evaluates to 138 ** a string which identifies a particular check-in of SQLite 139 ** within its configuration management system. ^The SQLITE_SOURCE_ID 140 ** string contains the date and time of the check-in (UTC) and a SHA1 141 ** or SHA3-256 hash of the entire source tree. If the source code has 142 ** been edited in any way since it was last checked in, then the last 143 ** four hexadecimal digits of the hash may be modified. 144 ** 145 ** See also: [sqlite3_libversion()], 146 ** [sqlite3_libversion_number()], [sqlite3_sourceid()], 147 ** [sqlite_version()] and [sqlite_source_id()]. 148 */ 149 #define SQLITE_VERSION "3.53.3" 150 #define SQLITE_VERSION_NUMBER 3053003 151 #define SQLITE_SOURCE_ID "2026-06-26 20:14:12 d4c0e51e4aeb96955b99185ab9cde75c339e2c29c3f3f12428d364a10d782c62" 152 #define SQLITE_SCM_BRANCH "branch-3.53" 153 #define SQLITE_SCM_TAGS "release version-3.53.3" 154 #define SQLITE_SCM_DATETIME "2026-06-26T20:14:12.354Z" 155 156 /* 157 ** CAPI3REF: Run-Time Library Version Numbers 158 ** KEYWORDS: sqlite3_version sqlite3_sourceid 159 ** 160 ** These interfaces provide the same information as the [SQLITE_VERSION], 161 ** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros 162 ** but are associated with the library instead of the header file. ^(Cautious 163 ** programmers might include assert() statements in their application to 164 ** verify that values returned by these interfaces match the macros in 165 ** the header, and thus ensure that the application is 166 ** compiled with matching library and header files. 167 ** 168 ** <blockquote><pre> 169 ** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER ); 170 ** assert( strncmp(sqlite3_sourceid(),SQLITE_SOURCE_ID,80)==0 ); 171 ** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 ); 172 ** </pre></blockquote>)^ 173 ** 174 ** ^The sqlite3_version[] string constant contains the text of the 175 ** [SQLITE_VERSION] macro. ^The sqlite3_libversion() function returns a 176 ** pointer to the sqlite3_version[] string constant. The sqlite3_libversion() 177 ** function is provided for use in DLLs since DLL users usually do not have 178 ** direct access to string constants within the DLL. ^The 179 ** sqlite3_libversion_number() function returns an integer equal to 180 ** [SQLITE_VERSION_NUMBER]. ^(The sqlite3_sourceid() function returns 181 ** a pointer to a string constant whose value is the same as the 182 ** [SQLITE_SOURCE_ID] C preprocessor macro. Except if SQLite is built 183 ** using an edited copy of [the amalgamation], then the last four characters 184 ** of the hash might be different from [SQLITE_SOURCE_ID].)^ 185 ** 186 ** See also: [sqlite_version()] and [sqlite_source_id()]. 187 */ 188 SQLITE_API SQLITE_EXTERN const char sqlite3_version[]; 189 SQLITE_API const char *sqlite3_libversion(void); 190 SQLITE_API const char *sqlite3_sourceid(void); 191 SQLITE_API int sqlite3_libversion_number(void); 192 193 /* 194 ** CAPI3REF: Run-Time Library Compilation Options Diagnostics 195 ** 196 ** ^The sqlite3_compileoption_used() function returns 0 or 1 197 ** indicating whether the specified option was defined at 198 ** compile time. ^The SQLITE_ prefix may be omitted from the 199 ** option name passed to sqlite3_compileoption_used(). 200 ** 201 ** ^The sqlite3_compileoption_get() function allows iterating 202 ** over the list of options that were defined at compile time by 203 ** returning the N-th compile time option string. ^If N is out of range, 204 ** sqlite3_compileoption_get() returns a NULL pointer. ^The SQLITE_ 205 ** prefix is omitted from any strings returned by 206 ** sqlite3_compileoption_get(). 207 ** 208 ** ^Support for the diagnostic functions sqlite3_compileoption_used() 209 ** and sqlite3_compileoption_get() may be omitted by specifying the 210 ** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time. 211 ** 212 ** See also: SQL functions [sqlite_compileoption_used()] and 213 ** [sqlite_compileoption_get()] and the [compile_options pragma]. 214 */ 215 #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS 216 SQLITE_API int sqlite3_compileoption_used(const char *zOptName); 217 SQLITE_API const char *sqlite3_compileoption_get(int N); 218 #else 219 # define sqlite3_compileoption_used(X) 0 220 # define sqlite3_compileoption_get(X) ((void*)0) 221 #endif 222 223 /* 224 ** CAPI3REF: Test To See If The Library Is Threadsafe 225 ** 226 ** ^The sqlite3_threadsafe() function returns zero if and only if 227 ** SQLite was compiled with mutexing code omitted due to the 228 ** [SQLITE_THREADSAFE] compile-time option being set to 0. 229 ** 230 ** SQLite can be compiled with or without mutexes. When 231 ** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes 232 ** are enabled and SQLite is threadsafe. When the 233 ** [SQLITE_THREADSAFE] macro is 0, 234 ** the mutexes are omitted. Without the mutexes, it is not safe 235 ** to use SQLite concurrently from more than one thread. 236 ** 237 ** Enabling mutexes incurs a measurable performance penalty. 238 ** So if speed is of utmost importance, it makes sense to disable 239 ** the mutexes. But for maximum safety, mutexes should be enabled. 240 ** ^The default behavior is for mutexes to be enabled. 241 ** 242 ** This interface can be used by an application to make sure that the 243 ** version of SQLite that it is linking against was compiled with 244 ** the desired setting of the [SQLITE_THREADSAFE] macro. 245 ** 246 ** This interface only reports on the compile-time mutex setting 247 ** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with 248 ** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but 249 ** can be fully or partially disabled using a call to [sqlite3_config()] 250 ** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD], 251 ** or [SQLITE_CONFIG_SERIALIZED]. ^(The return value of the 252 ** sqlite3_threadsafe() function shows only the compile-time setting of 253 ** thread safety, not any run-time changes to that setting made by 254 ** sqlite3_config(). In other words, the return value from sqlite3_threadsafe() 255 ** is unchanged by calls to sqlite3_config().)^ 256 ** 257 ** See the [threading mode] documentation for additional information. 258 */ 259 SQLITE_API int sqlite3_threadsafe(void); 260 261 /* 262 ** CAPI3REF: Database Connection Handle 263 ** KEYWORDS: {database connection} {database connections} 264 ** 265 ** Each open SQLite database is represented by a pointer to an instance of 266 ** the opaque structure named "sqlite3". It is useful to think of an sqlite3 267 ** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and 268 ** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()] 269 ** and [sqlite3_close_v2()] are its destructors. There are many other 270 ** interfaces (such as 271 ** [sqlite3_prepare_v2()], [sqlite3_create_function()], and 272 ** [sqlite3_busy_timeout()] to name but three) that are methods on an 273 ** sqlite3 object. 274 */ 275 typedef struct sqlite3 sqlite3; 276 277 /* 278 ** CAPI3REF: 64-Bit Integer Types 279 ** KEYWORDS: sqlite_int64 sqlite_uint64 280 ** 281 ** Because there is no cross-platform way to specify 64-bit integer types 282 ** SQLite includes typedefs for 64-bit signed and unsigned integers. 283 ** 284 ** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions. 285 ** The sqlite_int64 and sqlite_uint64 types are supported for backwards 286 ** compatibility only. 287 ** 288 ** ^The sqlite3_int64 and sqlite_int64 types can store integer values 289 ** between -9223372036854775808 and +9223372036854775807 inclusive. ^The 290 ** sqlite3_uint64 and sqlite_uint64 types can store integer values 291 ** between 0 and +18446744073709551615 inclusive. 292 */ 293 #ifdef SQLITE_INT64_TYPE 294 typedef SQLITE_INT64_TYPE sqlite_int64; 295 # ifdef SQLITE_UINT64_TYPE 296 typedef SQLITE_UINT64_TYPE sqlite_uint64; 297 # else 298 typedef unsigned SQLITE_INT64_TYPE sqlite_uint64; 299 # endif 300 #elif defined(_MSC_VER) || defined(__BORLANDC__) 301 typedef __int64 sqlite_int64; 302 typedef unsigned __int64 sqlite_uint64; 303 #else 304 typedef long long int sqlite_int64; 305 typedef unsigned long long int sqlite_uint64; 306 #endif 307 typedef sqlite_int64 sqlite3_int64; 308 typedef sqlite_uint64 sqlite3_uint64; 309 310 /* 311 ** If compiling for a processor that lacks floating point support, 312 ** substitute integer for floating-point. 313 */ 314 #ifdef SQLITE_OMIT_FLOATING_POINT 315 # define double sqlite3_int64 316 #endif 317 318 /* 319 ** CAPI3REF: Closing A Database Connection 320 ** DESTRUCTOR: sqlite3 321 ** 322 ** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors 323 ** for the [sqlite3] object. 324 ** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if 325 ** the [sqlite3] object is successfully destroyed and all associated 326 ** resources are deallocated. 327 ** 328 ** Ideally, applications should [sqlite3_finalize | finalize] all 329 ** [prepared statements], [sqlite3_blob_close | close] all [BLOB handles], and 330 ** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated 331 ** with the [sqlite3] object prior to attempting to close the object. 332 ** ^If the database connection is associated with unfinalized prepared 333 ** statements, BLOB handlers, and/or unfinished sqlite3_backup objects then 334 ** sqlite3_close() will leave the database connection open and return 335 ** [SQLITE_BUSY]. ^If sqlite3_close_v2() is called with unfinalized prepared 336 ** statements, unclosed BLOB handlers, and/or unfinished sqlite3_backups, 337 ** it returns [SQLITE_OK] regardless, but instead of deallocating the database 338 ** connection immediately, it marks the database connection as an unusable 339 ** "zombie" and makes arrangements to automatically deallocate the database 340 ** connection after all prepared statements are finalized, all BLOB handles 341 ** are closed, and all backups have finished. The sqlite3_close_v2() interface 342 ** is intended for use with host languages that are garbage collected, and 343 ** where the order in which destructors are called is arbitrary. 344 ** 345 ** ^If an [sqlite3] object is destroyed while a transaction is open, 346 ** the transaction is automatically rolled back. 347 ** 348 ** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)] 349 ** must be either a NULL 350 ** pointer or an [sqlite3] object pointer obtained 351 ** from [sqlite3_open()], [sqlite3_open16()], or 352 ** [sqlite3_open_v2()], and not previously closed. 353 ** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer 354 ** argument is a harmless no-op. 355 */ 356 SQLITE_API int sqlite3_close(sqlite3*); 357 SQLITE_API int sqlite3_close_v2(sqlite3*); 358 359 /* 360 ** The type for a callback function. 361 ** This is legacy and deprecated. It is included for historical 362 ** compatibility and is not documented. 363 */ 364 typedef int (*sqlite3_callback)(void*,int,char**, char**); 365 366 /* 367 ** CAPI3REF: One-Step Query Execution Interface 368 ** METHOD: sqlite3 369 ** 370 ** The sqlite3_exec() interface is a convenience wrapper around 371 ** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()], 372 ** that allows an application to run multiple statements of SQL 373 ** without having to use a lot of C code. 374 ** 375 ** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded, 376 ** semicolon-separated SQL statements passed into its 2nd argument, 377 ** in the context of the [database connection] passed in as its 1st 378 ** argument. ^If the callback function of the 3rd argument to 379 ** sqlite3_exec() is not NULL, then it is invoked for each result row 380 ** coming out of the evaluated SQL statements. ^The 4th argument to 381 ** sqlite3_exec() is relayed through to the 1st argument of each 382 ** callback invocation. ^If the callback pointer to sqlite3_exec() 383 ** is NULL, then no callback is ever invoked and result rows are 384 ** ignored. 385 ** 386 ** ^If an error occurs while evaluating the SQL statements passed into 387 ** sqlite3_exec(), then execution of the current statement stops and 388 ** subsequent statements are skipped. ^If the 5th parameter to sqlite3_exec() 389 ** is not NULL then any error message is written into memory obtained 390 ** from [sqlite3_malloc()] and passed back through the 5th parameter. 391 ** To avoid memory leaks, the application should invoke [sqlite3_free()] 392 ** on error message strings returned through the 5th parameter of 393 ** sqlite3_exec() after the error message string is no longer needed. 394 ** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors 395 ** occur, then sqlite3_exec() sets the pointer in its 5th parameter to 396 ** NULL before returning. 397 ** 398 ** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec() 399 ** routine returns SQLITE_ABORT without invoking the callback again and 400 ** without running any subsequent SQL statements. 401 ** 402 ** ^The 2nd argument to the sqlite3_exec() callback function is the 403 ** number of columns in the result. ^The 3rd argument to the sqlite3_exec() 404 ** callback is an array of pointers to strings obtained as if from 405 ** [sqlite3_column_text()], one for each column. ^If an element of a 406 ** result row is NULL then the corresponding string pointer for the 407 ** sqlite3_exec() callback is a NULL pointer. ^The 4th argument to the 408 ** sqlite3_exec() callback is an array of pointers to strings where each 409 ** entry represents the name of a corresponding result column as obtained 410 ** from [sqlite3_column_name()]. 411 ** 412 ** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer 413 ** to an empty string, or a pointer that contains only whitespace and/or 414 ** SQL comments, then no SQL statements are evaluated and the database 415 ** is not changed. 416 ** 417 ** Restrictions: 418 ** 419 ** <ul> 420 ** <li> The application must ensure that the 1st parameter to sqlite3_exec() 421 ** is a valid and open [database connection]. 422 ** <li> The application must not close the [database connection] specified by 423 ** the 1st parameter to sqlite3_exec() while sqlite3_exec() is running. 424 ** <li> The application must not modify the SQL statement text passed into 425 ** the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running. 426 ** <li> The application must not dereference the arrays or string pointers 427 ** passed as the 3rd and 4th callback parameters after it returns. 428 ** </ul> 429 */ 430 SQLITE_API int sqlite3_exec( 431 sqlite3*, /* An open database */ 432 const char *sql, /* SQL to be evaluated */ 433 int (*callback)(void*,int,char**,char**), /* Callback function */ 434 void *, /* 1st argument to callback */ 435 char **errmsg /* Error msg written here */ 436 ); 437 438 /* 439 ** CAPI3REF: Result Codes 440 ** KEYWORDS: {result code definitions} 441 ** 442 ** Many SQLite functions return an integer result code from the set shown 443 ** here in order to indicate success or failure. 444 ** 445 ** New error codes may be added in future versions of SQLite. 446 ** 447 ** See also: [extended result code definitions] 448 */ 449 #define SQLITE_OK 0 /* Successful result */ 450 /* beginning-of-error-codes */ 451 #define SQLITE_ERROR 1 /* Generic error */ 452 #define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */ 453 #define SQLITE_PERM 3 /* Access permission denied */ 454 #define SQLITE_ABORT 4 /* Callback routine requested an abort */ 455 #define SQLITE_BUSY 5 /* The database file is locked */ 456 #define SQLITE_LOCKED 6 /* A table in the database is locked */ 457 #define SQLITE_NOMEM 7 /* A malloc() failed */ 458 #define SQLITE_READONLY 8 /* Attempt to write a readonly database */ 459 #define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/ 460 #define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */ 461 #define SQLITE_CORRUPT 11 /* The database disk image is malformed */ 462 #define SQLITE_NOTFOUND 12 /* Unknown opcode in sqlite3_file_control() */ 463 #define SQLITE_FULL 13 /* Insertion failed because database is full */ 464 #define SQLITE_CANTOPEN 14 /* Unable to open the database file */ 465 #define SQLITE_PROTOCOL 15 /* Database lock protocol error */ 466 #define SQLITE_EMPTY 16 /* Internal use only */ 467 #define SQLITE_SCHEMA 17 /* The database schema changed */ 468 #define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */ 469 #define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */ 470 #define SQLITE_MISMATCH 20 /* Data type mismatch */ 471 #define SQLITE_MISUSE 21 /* Library used incorrectly */ 472 #define SQLITE_NOLFS 22 /* Uses OS features not supported on host */ 473 #define SQLITE_AUTH 23 /* Authorization denied */ 474 #define SQLITE_FORMAT 24 /* Not used */ 475 #define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */ 476 #define SQLITE_NOTADB 26 /* File opened that is not a database file */ 477 #define SQLITE_NOTICE 27 /* Notifications from sqlite3_log() */ 478 #define SQLITE_WARNING 28 /* Warnings from sqlite3_log() */ 479 #define SQLITE_ROW 100 /* sqlite3_step() has another row ready */ 480 #define SQLITE_DONE 101 /* sqlite3_step() has finished executing */ 481 /* end-of-error-codes */ 482 483 /* 484 ** CAPI3REF: Extended Result Codes 485 ** KEYWORDS: {extended result code definitions} 486 ** 487 ** In its default configuration, SQLite API routines return one of 30 integer 488 ** [result codes]. However, experience has shown that many of 489 ** these result codes are too coarse-grained. They do not provide as 490 ** much information about problems as programmers might like. In an effort to 491 ** address this, newer versions of SQLite (version 3.3.8 [dateof:3.3.8] 492 ** and later) include 493 ** support for additional result codes that provide more detailed information 494 ** about errors. These [extended result codes] are enabled or disabled 495 ** on a per database connection basis using the 496 ** [sqlite3_extended_result_codes()] API. Or, the extended code for 497 ** the most recent error can be obtained using 498 ** [sqlite3_extended_errcode()]. 499 */ 500 #define SQLITE_ERROR_MISSING_COLLSEQ (SQLITE_ERROR | (1<<8)) 501 #define SQLITE_ERROR_RETRY (SQLITE_ERROR | (2<<8)) 502 #define SQLITE_ERROR_SNAPSHOT (SQLITE_ERROR | (3<<8)) 503 #define SQLITE_ERROR_RESERVESIZE (SQLITE_ERROR | (4<<8)) 504 #define SQLITE_ERROR_KEY (SQLITE_ERROR | (5<<8)) 505 #define SQLITE_ERROR_UNABLE (SQLITE_ERROR | (6<<8)) 506 #define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8)) 507 #define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8)) 508 #define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8)) 509 #define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8)) 510 #define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8)) 511 #define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8)) 512 #define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8)) 513 #define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8)) 514 #define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8)) 515 #define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8)) 516 #define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8)) 517 #define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8)) 518 #define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8)) 519 #define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8)) 520 #define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8)) 521 #define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8)) 522 #define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8)) 523 #define SQLITE_IOERR_SHMOPEN (SQLITE_IOERR | (18<<8)) 524 #define SQLITE_IOERR_SHMSIZE (SQLITE_IOERR | (19<<8)) 525 #define SQLITE_IOERR_SHMLOCK (SQLITE_IOERR | (20<<8)) 526 #define SQLITE_IOERR_SHMMAP (SQLITE_IOERR | (21<<8)) 527 #define SQLITE_IOERR_SEEK (SQLITE_IOERR | (22<<8)) 528 #define SQLITE_IOERR_DELETE_NOENT (SQLITE_IOERR | (23<<8)) 529 #define SQLITE_IOERR_MMAP (SQLITE_IOERR | (24<<8)) 530 #define SQLITE_IOERR_GETTEMPPATH (SQLITE_IOERR | (25<<8)) 531 #define SQLITE_IOERR_CONVPATH (SQLITE_IOERR | (26<<8)) 532 #define SQLITE_IOERR_VNODE (SQLITE_IOERR | (27<<8)) 533 #define SQLITE_IOERR_AUTH (SQLITE_IOERR | (28<<8)) 534 #define SQLITE_IOERR_BEGIN_ATOMIC (SQLITE_IOERR | (29<<8)) 535 #define SQLITE_IOERR_COMMIT_ATOMIC (SQLITE_IOERR | (30<<8)) 536 #define SQLITE_IOERR_ROLLBACK_ATOMIC (SQLITE_IOERR | (31<<8)) 537 #define SQLITE_IOERR_DATA (SQLITE_IOERR | (32<<8)) 538 #define SQLITE_IOERR_CORRUPTFS (SQLITE_IOERR | (33<<8)) 539 #define SQLITE_IOERR_IN_PAGE (SQLITE_IOERR | (34<<8)) 540 #define SQLITE_IOERR_BADKEY (SQLITE_IOERR | (35<<8)) 541 #define SQLITE_IOERR_CODEC (SQLITE_IOERR | (36<<8)) 542 #define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8)) 543 #define SQLITE_LOCKED_VTAB (SQLITE_LOCKED | (2<<8)) 544 #define SQLITE_BUSY_RECOVERY (SQLITE_BUSY | (1<<8)) 545 #define SQLITE_BUSY_SNAPSHOT (SQLITE_BUSY | (2<<8)) 546 #define SQLITE_BUSY_TIMEOUT (SQLITE_BUSY | (3<<8)) 547 #define SQLITE_CANTOPEN_NOTEMPDIR (SQLITE_CANTOPEN | (1<<8)) 548 #define SQLITE_CANTOPEN_ISDIR (SQLITE_CANTOPEN | (2<<8)) 549 #define SQLITE_CANTOPEN_FULLPATH (SQLITE_CANTOPEN | (3<<8)) 550 #define SQLITE_CANTOPEN_CONVPATH (SQLITE_CANTOPEN | (4<<8)) 551 #define SQLITE_CANTOPEN_DIRTYWAL (SQLITE_CANTOPEN | (5<<8)) /* Not Used */ 552 #define SQLITE_CANTOPEN_SYMLINK (SQLITE_CANTOPEN | (6<<8)) 553 #define SQLITE_CORRUPT_VTAB (SQLITE_CORRUPT | (1<<8)) 554 #define SQLITE_CORRUPT_SEQUENCE (SQLITE_CORRUPT | (2<<8)) 555 #define SQLITE_CORRUPT_INDEX (SQLITE_CORRUPT | (3<<8)) 556 #define SQLITE_READONLY_RECOVERY (SQLITE_READONLY | (1<<8)) 557 #define SQLITE_READONLY_CANTLOCK (SQLITE_READONLY | (2<<8)) 558 #define SQLITE_READONLY_ROLLBACK (SQLITE_READONLY | (3<<8)) 559 #define SQLITE_READONLY_DBMOVED (SQLITE_READONLY | (4<<8)) 560 #define SQLITE_READONLY_CANTINIT (SQLITE_READONLY | (5<<8)) 561 #define SQLITE_READONLY_DIRECTORY (SQLITE_READONLY | (6<<8)) 562 #define SQLITE_ABORT_ROLLBACK (SQLITE_ABORT | (2<<8)) 563 #define SQLITE_CONSTRAINT_CHECK (SQLITE_CONSTRAINT | (1<<8)) 564 #define SQLITE_CONSTRAINT_COMMITHOOK (SQLITE_CONSTRAINT | (2<<8)) 565 #define SQLITE_CONSTRAINT_FOREIGNKEY (SQLITE_CONSTRAINT | (3<<8)) 566 #define SQLITE_CONSTRAINT_FUNCTION (SQLITE_CONSTRAINT | (4<<8)) 567 #define SQLITE_CONSTRAINT_NOTNULL (SQLITE_CONSTRAINT | (5<<8)) 568 #define SQLITE_CONSTRAINT_PRIMARYKEY (SQLITE_CONSTRAINT | (6<<8)) 569 #define SQLITE_CONSTRAINT_TRIGGER (SQLITE_CONSTRAINT | (7<<8)) 570 #define SQLITE_CONSTRAINT_UNIQUE (SQLITE_CONSTRAINT | (8<<8)) 571 #define SQLITE_CONSTRAINT_VTAB (SQLITE_CONSTRAINT | (9<<8)) 572 #define SQLITE_CONSTRAINT_ROWID (SQLITE_CONSTRAINT |(10<<8)) 573 #define SQLITE_CONSTRAINT_PINNED (SQLITE_CONSTRAINT |(11<<8)) 574 #define SQLITE_CONSTRAINT_DATATYPE (SQLITE_CONSTRAINT |(12<<8)) 575 #define SQLITE_NOTICE_RECOVER_WAL (SQLITE_NOTICE | (1<<8)) 576 #define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8)) 577 #define SQLITE_NOTICE_RBU (SQLITE_NOTICE | (3<<8)) 578 #define SQLITE_WARNING_AUTOINDEX (SQLITE_WARNING | (1<<8)) 579 #define SQLITE_AUTH_USER (SQLITE_AUTH | (1<<8)) 580 #define SQLITE_OK_LOAD_PERMANENTLY (SQLITE_OK | (1<<8)) 581 #define SQLITE_OK_SYMLINK (SQLITE_OK | (2<<8)) /* internal only */ 582 583 /* 584 ** CAPI3REF: Flags For File Open Operations 585 ** 586 ** These bit values are intended for use in the 587 ** 3rd parameter to the [sqlite3_open_v2()] interface and 588 ** in the 4th parameter to the [sqlite3_vfs.xOpen] method. 589 ** 590 ** Only those flags marked as "Ok for sqlite3_open_v2()" may be 591 ** used as the third argument to the [sqlite3_open_v2()] interface. 592 ** The other flags have historically been ignored by sqlite3_open_v2(), 593 ** though future versions of SQLite might change so that an error is 594 ** raised if any of the disallowed bits are passed into sqlite3_open_v2(). 595 ** Applications should not depend on the historical behavior. 596 ** 597 ** Note in particular that passing the SQLITE_OPEN_EXCLUSIVE flag into 598 ** [sqlite3_open_v2()] does *not* cause the underlying database file 599 ** to be opened using O_EXCL. Passing SQLITE_OPEN_EXCLUSIVE into 600 ** [sqlite3_open_v2()] has historically been a no-op and might become an 601 ** error in future versions of SQLite. 602 */ 603 #define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */ 604 #define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */ 605 #define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */ 606 #define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */ 607 #define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */ 608 #define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */ 609 #define SQLITE_OPEN_URI 0x00000040 /* Ok for sqlite3_open_v2() */ 610 #define SQLITE_OPEN_MEMORY 0x00000080 /* Ok for sqlite3_open_v2() */ 611 #define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */ 612 #define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */ 613 #define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */ 614 #define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */ 615 #define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */ 616 #define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */ 617 #define SQLITE_OPEN_SUPER_JOURNAL 0x00004000 /* VFS only */ 618 #define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */ 619 #define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */ 620 #define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */ 621 #define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */ 622 #define SQLITE_OPEN_WAL 0x00080000 /* VFS only */ 623 #define SQLITE_OPEN_NOFOLLOW 0x01000000 /* Ok for sqlite3_open_v2() */ 624 #define SQLITE_OPEN_EXRESCODE 0x02000000 /* Extended result codes */ 625 626 /* Reserved: 0x00F00000 */ 627 /* Legacy compatibility: */ 628 #define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */ 629 630 631 /* 632 ** CAPI3REF: Device Characteristics 633 ** 634 ** The xDeviceCharacteristics method of the [sqlite3_io_methods] 635 ** object returns an integer which is a vector of these 636 ** bit values expressing I/O characteristics of the mass storage 637 ** device that holds the file that the [sqlite3_io_methods] 638 ** refers to. 639 ** 640 ** The SQLITE_IOCAP_ATOMIC property means that all writes of 641 ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values 642 ** mean that writes of blocks that are nnn bytes in size and 643 ** are aligned to an address which is an integer multiple of 644 ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means 645 ** that when data is appended to a file, the data is appended 646 ** first then the size of the file is extended, never the other 647 ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that 648 ** information is written to disk in the same order as calls 649 ** to xWrite(). The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that 650 ** after reboot following a crash or power loss, the only bytes in a 651 ** file that were written at the application level might have changed 652 ** and that adjacent bytes, even bytes within the same sector are 653 ** guaranteed to be unchanged. The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 654 ** flag indicates that a file cannot be deleted when open. The 655 ** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on 656 ** read-only media and cannot be changed even by processes with 657 ** elevated privileges. 658 ** 659 ** The SQLITE_IOCAP_BATCH_ATOMIC property means that the underlying 660 ** filesystem supports doing multiple write operations atomically when those 661 ** write operations are bracketed by [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] and 662 ** [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]. 663 ** 664 ** The SQLITE_IOCAP_SUBPAGE_READ property means that it is ok to read 665 ** from the database file in amounts that are not a multiple of the 666 ** page size and that do not begin at a page boundary. Without this 667 ** property, SQLite is careful to only do full-page reads and write 668 ** on aligned pages, with the one exception that it will do a sub-page 669 ** read of the first page to access the database header. 670 */ 671 #define SQLITE_IOCAP_ATOMIC 0x00000001 672 #define SQLITE_IOCAP_ATOMIC512 0x00000002 673 #define SQLITE_IOCAP_ATOMIC1K 0x00000004 674 #define SQLITE_IOCAP_ATOMIC2K 0x00000008 675 #define SQLITE_IOCAP_ATOMIC4K 0x00000010 676 #define SQLITE_IOCAP_ATOMIC8K 0x00000020 677 #define SQLITE_IOCAP_ATOMIC16K 0x00000040 678 #define SQLITE_IOCAP_ATOMIC32K 0x00000080 679 #define SQLITE_IOCAP_ATOMIC64K 0x00000100 680 #define SQLITE_IOCAP_SAFE_APPEND 0x00000200 681 #define SQLITE_IOCAP_SEQUENTIAL 0x00000400 682 #define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 0x00000800 683 #define SQLITE_IOCAP_POWERSAFE_OVERWRITE 0x00001000 684 #define SQLITE_IOCAP_IMMUTABLE 0x00002000 685 #define SQLITE_IOCAP_BATCH_ATOMIC 0x00004000 686 #define SQLITE_IOCAP_SUBPAGE_READ 0x00008000 687 688 /* 689 ** CAPI3REF: File Locking Levels 690 ** 691 ** SQLite uses one of these integer values as the second 692 ** argument to calls it makes to the xLock() and xUnlock() methods 693 ** of an [sqlite3_io_methods] object. These values are ordered from 694 ** least restrictive to most restrictive. 695 ** 696 ** The argument to xLock() is always SHARED or higher. The argument to 697 ** xUnlock is either SHARED or NONE. 698 */ 699 #define SQLITE_LOCK_NONE 0 /* xUnlock() only */ 700 #define SQLITE_LOCK_SHARED 1 /* xLock() or xUnlock() */ 701 #define SQLITE_LOCK_RESERVED 2 /* xLock() only */ 702 #define SQLITE_LOCK_PENDING 3 /* xLock() only */ 703 #define SQLITE_LOCK_EXCLUSIVE 4 /* xLock() only */ 704 705 /* 706 ** CAPI3REF: Synchronization Type Flags 707 ** 708 ** When SQLite invokes the xSync() method of an 709 ** [sqlite3_io_methods] object it uses a combination of 710 ** these integer values as the second argument. 711 ** 712 ** When the SQLITE_SYNC_DATAONLY flag is used, it means that the 713 ** sync operation only needs to flush data to mass storage. Inode 714 ** information need not be flushed. If the lower four bits of the flag 715 ** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics. 716 ** If the lower four bits equal SQLITE_SYNC_FULL, that means 717 ** to use Mac OS X style fullsync instead of fsync(). 718 ** 719 ** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags 720 ** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL 721 ** settings. The [synchronous pragma] determines when calls to the 722 ** xSync VFS method occur and applies uniformly across all platforms. 723 ** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how 724 ** energetic or rigorous or forceful the sync operations are and 725 ** only make a difference on Mac OSX for the default SQLite code. 726 ** (Third-party VFS implementations might also make the distinction 727 ** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the 728 ** operating systems natively supported by SQLite, only Mac OSX 729 ** cares about the difference.) 730 */ 731 #define SQLITE_SYNC_NORMAL 0x00002 732 #define SQLITE_SYNC_FULL 0x00003 733 #define SQLITE_SYNC_DATAONLY 0x00010 734 735 /* 736 ** CAPI3REF: OS Interface Open File Handle 737 ** 738 ** An [sqlite3_file] object represents an open file in the 739 ** [sqlite3_vfs | OS interface layer]. Individual OS interface 740 ** implementations will 741 ** want to subclass this object by appending additional fields 742 ** for their own use. The pMethods entry is a pointer to an 743 ** [sqlite3_io_methods] object that defines methods for performing 744 ** I/O operations on the open file. 745 */ 746 typedef struct sqlite3_file sqlite3_file; 747 struct sqlite3_file { 748 const struct sqlite3_io_methods *pMethods; /* Methods for an open file */ 749 }; 750 751 /* 752 ** CAPI3REF: OS Interface File Virtual Methods Object 753 ** 754 ** Every file opened by the [sqlite3_vfs.xOpen] method populates an 755 ** [sqlite3_file] object (or, more commonly, a subclass of the 756 ** [sqlite3_file] object) with a pointer to an instance of this object. 757 ** This object defines the methods used to perform various operations 758 ** against the open file represented by the [sqlite3_file] object. 759 ** 760 ** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element 761 ** to a non-NULL pointer, then the sqlite3_io_methods.xClose method 762 ** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed. The 763 ** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen] 764 ** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element 765 ** to NULL. 766 ** 767 ** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or 768 ** [SQLITE_SYNC_FULL]. The first choice is the normal fsync(). 769 ** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY] 770 ** flag may be ORed in to indicate that only the data of the file 771 ** and not its inode needs to be synced. 772 ** 773 ** The integer values to xLock() and xUnlock() are one of 774 ** <ul> 775 ** <li> [SQLITE_LOCK_NONE], 776 ** <li> [SQLITE_LOCK_SHARED], 777 ** <li> [SQLITE_LOCK_RESERVED], 778 ** <li> [SQLITE_LOCK_PENDING], or 779 ** <li> [SQLITE_LOCK_EXCLUSIVE]. 780 ** </ul> 781 ** xLock() upgrades the database file lock. In other words, xLock() moves the 782 ** database file lock in the direction NONE toward EXCLUSIVE. The argument to 783 ** xLock() is always one of SHARED, RESERVED, PENDING, or EXCLUSIVE, never 784 ** SQLITE_LOCK_NONE. If the database file lock is already at or above the 785 ** requested lock, then the call to xLock() is a no-op. 786 ** xUnlock() downgrades the database file lock to either SHARED or NONE. 787 ** If the lock is already at or below the requested lock state, then the call 788 ** to xUnlock() is a no-op. 789 ** The xCheckReservedLock() method checks whether any database connection, 790 ** either in this process or in some other process, is holding a RESERVED, 791 ** PENDING, or EXCLUSIVE lock on the file. It returns, via its output 792 ** pointer parameter, true if such a lock exists and false otherwise. 793 ** 794 ** The xFileControl() method is a generic interface that allows custom 795 ** VFS implementations to directly control an open file using the 796 ** [sqlite3_file_control()] interface. The second "op" argument is an 797 ** integer opcode. The third argument is a generic pointer intended to 798 ** point to a structure that may contain arguments or space in which to 799 ** write return values. Potential uses for xFileControl() might be 800 ** functions to enable blocking locks with timeouts, to change the 801 ** locking strategy (for example to use dot-file locks), to inquire 802 ** about the status of a lock, or to break stale locks. The SQLite 803 ** core reserves all opcodes less than 100 for its own use. 804 ** A [file control opcodes | list of opcodes] less than 100 is available. 805 ** Applications that define a custom xFileControl method should use opcodes 806 ** greater than 100 to avoid conflicts. VFS implementations should 807 ** return [SQLITE_NOTFOUND] for file control opcodes that they do not 808 ** recognize. 809 ** 810 ** The xSectorSize() method returns the sector size of the 811 ** device that underlies the file. The sector size is the 812 ** minimum write that can be performed without disturbing 813 ** other bytes in the file. The xDeviceCharacteristics() 814 ** method returns a bit vector describing behaviors of the 815 ** underlying device: 816 ** 817 ** <ul> 818 ** <li> [SQLITE_IOCAP_ATOMIC] 819 ** <li> [SQLITE_IOCAP_ATOMIC512] 820 ** <li> [SQLITE_IOCAP_ATOMIC1K] 821 ** <li> [SQLITE_IOCAP_ATOMIC2K] 822 ** <li> [SQLITE_IOCAP_ATOMIC4K] 823 ** <li> [SQLITE_IOCAP_ATOMIC8K] 824 ** <li> [SQLITE_IOCAP_ATOMIC16K] 825 ** <li> [SQLITE_IOCAP_ATOMIC32K] 826 ** <li> [SQLITE_IOCAP_ATOMIC64K] 827 ** <li> [SQLITE_IOCAP_SAFE_APPEND] 828 ** <li> [SQLITE_IOCAP_SEQUENTIAL] 829 ** <li> [SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN] 830 ** <li> [SQLITE_IOCAP_POWERSAFE_OVERWRITE] 831 ** <li> [SQLITE_IOCAP_IMMUTABLE] 832 ** <li> [SQLITE_IOCAP_BATCH_ATOMIC] 833 ** <li> [SQLITE_IOCAP_SUBPAGE_READ] 834 ** </ul> 835 ** 836 ** The SQLITE_IOCAP_ATOMIC property means that all writes of 837 ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values 838 ** mean that writes of blocks that are nnn bytes in size and 839 ** are aligned to an address which is an integer multiple of 840 ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means 841 ** that when data is appended to a file, the data is appended 842 ** first then the size of the file is extended, never the other 843 ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that 844 ** information is written to disk in the same order as calls 845 ** to xWrite(). 846 ** 847 ** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill 848 ** in the unread portions of the buffer with zeros. A VFS that 849 ** fails to zero-fill short reads might seem to work. However, 850 ** failure to zero-fill short reads will eventually lead to 851 ** database corruption. 852 */ 853 typedef struct sqlite3_io_methods sqlite3_io_methods; 854 struct sqlite3_io_methods { 855 int iVersion; 856 int (*xClose)(sqlite3_file*); 857 int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst); 858 int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst); 859 int (*xTruncate)(sqlite3_file*, sqlite3_int64 size); 860 int (*xSync)(sqlite3_file*, int flags); 861 int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize); 862 int (*xLock)(sqlite3_file*, int); 863 int (*xUnlock)(sqlite3_file*, int); 864 int (*xCheckReservedLock)(sqlite3_file*, int *pResOut); 865 int (*xFileControl)(sqlite3_file*, int op, void *pArg); 866 int (*xSectorSize)(sqlite3_file*); 867 int (*xDeviceCharacteristics)(sqlite3_file*); 868 /* Methods above are valid for version 1 */ 869 int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**); 870 int (*xShmLock)(sqlite3_file*, int offset, int n, int flags); 871 void (*xShmBarrier)(sqlite3_file*); 872 int (*xShmUnmap)(sqlite3_file*, int deleteFlag); 873 /* Methods above are valid for version 2 */ 874 int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp); 875 int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p); 876 /* Methods above are valid for version 3 */ 877 /* Additional methods may be added in future releases */ 878 }; 879 880 /* 881 ** CAPI3REF: Standard File Control Opcodes 882 ** KEYWORDS: {file control opcodes} {file control opcode} 883 ** 884 ** These integer constants are opcodes for the xFileControl method 885 ** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()] 886 ** interface. 887 ** 888 ** <ul> 889 ** <li>[[SQLITE_FCNTL_LOCKSTATE]] 890 ** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This 891 ** opcode causes the xFileControl method to write the current state of 892 ** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED], 893 ** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE]) 894 ** into an integer that the pArg argument points to. 895 ** This capability is only available if SQLite is compiled with [SQLITE_DEBUG]. 896 ** 897 ** <li>[[SQLITE_FCNTL_SIZE_HINT]] 898 ** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS 899 ** layer a hint of how large the database file will grow to be during the 900 ** current transaction. This hint is not guaranteed to be accurate but it 901 ** is often close. The underlying VFS might choose to preallocate database 902 ** file space based on this hint in order to help writes to the database 903 ** file run faster. 904 ** 905 ** <li>[[SQLITE_FCNTL_SIZE_LIMIT]] 906 ** The [SQLITE_FCNTL_SIZE_LIMIT] opcode is used by in-memory VFS that 907 ** implements [sqlite3_deserialize()] to set an upper bound on the size 908 ** of the in-memory database. The argument is a pointer to a [sqlite3_int64]. 909 ** If the integer pointed to is negative, then it is filled in with the 910 ** current limit. Otherwise the limit is set to the larger of the value 911 ** of the integer pointed to and the current database size. The integer 912 ** pointed to is set to the new limit. 913 ** 914 ** <li>[[SQLITE_FCNTL_CHUNK_SIZE]] 915 ** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS 916 ** extends and truncates the database file in chunks of a size specified 917 ** by the user. The fourth argument to [sqlite3_file_control()] should 918 ** point to an integer (type int) containing the new chunk-size to use 919 ** for the nominated database. Allocating database file space in large 920 ** chunks (say 1MB at a time), may reduce file-system fragmentation and 921 ** improve performance on some systems. 922 ** 923 ** <li>[[SQLITE_FCNTL_FILE_POINTER]] 924 ** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer 925 ** to the [sqlite3_file] object associated with a particular database 926 ** connection. See also [SQLITE_FCNTL_JOURNAL_POINTER]. 927 ** 928 ** <li>[[SQLITE_FCNTL_JOURNAL_POINTER]] 929 ** The [SQLITE_FCNTL_JOURNAL_POINTER] opcode is used to obtain a pointer 930 ** to the [sqlite3_file] object associated with the journal file (either 931 ** the [rollback journal] or the [write-ahead log]) for a particular database 932 ** connection. See also [SQLITE_FCNTL_FILE_POINTER]. 933 ** 934 ** <li>[[SQLITE_FCNTL_SYNC_OMITTED]] 935 ** The SQLITE_FCNTL_SYNC_OMITTED file-control is no longer used. 936 ** 937 ** <li>[[SQLITE_FCNTL_SYNC]] 938 ** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and 939 ** sent to the VFS immediately before the xSync method is invoked on a 940 ** database file descriptor. Or, if the xSync method is not invoked 941 ** because the user has configured SQLite with 942 ** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place 943 ** of the xSync method. In most cases, the pointer argument passed with 944 ** this file-control is NULL. However, if the database file is being synced 945 ** as part of a multi-database commit, the argument points to a nul-terminated 946 ** string containing the transactions super-journal file name. VFSes that 947 ** do not need this signal should silently ignore this opcode. Applications 948 ** should not call [sqlite3_file_control()] with this opcode as doing so may 949 ** disrupt the operation of the specialized VFSes that do require it. 950 ** 951 ** <li>[[SQLITE_FCNTL_COMMIT_PHASETWO]] 952 ** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite 953 ** and sent to the VFS after a transaction has been committed immediately 954 ** but before the database is unlocked. VFSes that do not need this signal 955 ** should silently ignore this opcode. Applications should not call 956 ** [sqlite3_file_control()] with this opcode as doing so may disrupt the 957 ** operation of the specialized VFSes that do require it. 958 ** 959 ** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]] 960 ** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic 961 ** retry counts and intervals for certain disk I/O operations for the 962 ** windows [VFS] in order to provide robustness in the presence of 963 ** anti-virus programs. By default, the windows VFS will retry file read, 964 ** file write, and file delete operations up to 10 times, with a delay 965 ** of 25 milliseconds before the first retry and with the delay increasing 966 ** by an additional 25 milliseconds with each subsequent retry. This 967 ** opcode allows these two values (10 retries and 25 milliseconds of delay) 968 ** to be adjusted. The values are changed for all database connections 969 ** within the same process. The argument is a pointer to an array of two 970 ** integers where the first integer is the new retry count and the second 971 ** integer is the delay. If either integer is negative, then the setting 972 ** is not changed but instead the prior value of that setting is written 973 ** into the array entry, allowing the current retry settings to be 974 ** interrogated. The zDbName parameter is ignored. 975 ** 976 ** <li>[[SQLITE_FCNTL_PERSIST_WAL]] 977 ** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the 978 ** persistent [WAL | Write Ahead Log] setting. By default, the auxiliary 979 ** write ahead log ([WAL file]) and shared memory 980 ** files used for transaction control 981 ** are automatically deleted when the latest connection to the database 982 ** closes. Setting persistent WAL mode causes those files to persist after 983 ** close. Persisting the files is useful when other processes that do not 984 ** have write permission on the directory containing the database file want 985 ** to read the database file, as the WAL and shared memory files must exist 986 ** in order for the database to be readable. The fourth parameter to 987 ** [sqlite3_file_control()] for this opcode should be a pointer to an integer. 988 ** That integer is 0 to disable persistent WAL mode or 1 to enable persistent 989 ** WAL mode. If the integer is -1, then it is overwritten with the current 990 ** WAL persistence setting. 991 ** 992 ** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]] 993 ** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the 994 ** persistent "powersafe-overwrite" or "PSOW" setting. The PSOW setting 995 ** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the 996 ** xDeviceCharacteristics methods. The fourth parameter to 997 ** [sqlite3_file_control()] for this opcode should be a pointer to an integer. 998 ** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage 999 ** mode. If the integer is -1, then it is overwritten with the current 1000 ** zero-damage mode setting. 1001 ** 1002 ** <li>[[SQLITE_FCNTL_OVERWRITE]] 1003 ** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening 1004 ** a write transaction to indicate that, unless it is rolled back for some 1005 ** reason, the entire database file will be overwritten by the current 1006 ** transaction. This is used by VACUUM operations. 1007 ** 1008 ** <li>[[SQLITE_FCNTL_VFSNAME]] 1009 ** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of 1010 ** all [VFSes] in the VFS stack. The names of all VFS shims and the 1011 ** final bottom-level VFS are written into memory obtained from 1012 ** [sqlite3_malloc()] and the result is stored in the char* variable 1013 ** that the fourth parameter of [sqlite3_file_control()] points to. 1014 ** The caller is responsible for freeing the memory when done. As with 1015 ** all file-control actions, there is no guarantee that this will actually 1016 ** do anything. Callers should initialize the char* variable to a NULL 1017 ** pointer in case this file-control is not implemented. This file-control 1018 ** is intended for diagnostic use only. 1019 ** 1020 ** <li>[[SQLITE_FCNTL_VFS_POINTER]] 1021 ** ^The [SQLITE_FCNTL_VFS_POINTER] opcode finds a pointer to the top-level 1022 ** [VFSes] currently in use. ^(The argument X in 1023 ** sqlite3_file_control(db,SQLITE_FCNTL_VFS_POINTER,X) must be 1024 ** of type "[sqlite3_vfs] **". This opcode will set *X 1025 ** to a pointer to the top-level VFS.)^ 1026 ** ^When there are multiple VFS shims in the stack, this opcode finds the 1027 ** upper-most shim only. 1028 ** 1029 ** <li>[[SQLITE_FCNTL_PRAGMA]] 1030 ** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA] 1031 ** file control is sent to the open [sqlite3_file] object corresponding 1032 ** to the database file to which the pragma statement refers. ^The argument 1033 ** to the [SQLITE_FCNTL_PRAGMA] file control is an array of 1034 ** pointers to strings (char**) in which the second element of the array 1035 ** is the name of the pragma and the third element is the argument to the 1036 ** pragma or NULL if the pragma has no argument. ^The handler for an 1037 ** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element 1038 ** of the char** argument point to a string obtained from [sqlite3_mprintf()] 1039 ** or the equivalent and that string will become the result of the pragma or 1040 ** the error message if the pragma fails. ^If the 1041 ** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal 1042 ** [PRAGMA] processing continues. ^If the [SQLITE_FCNTL_PRAGMA] 1043 ** file control returns [SQLITE_OK], then the parser assumes that the 1044 ** VFS has handled the PRAGMA itself and the parser generates a no-op 1045 ** prepared statement if result string is NULL, or that returns a copy 1046 ** of the result string if the string is non-NULL. 1047 ** ^If the [SQLITE_FCNTL_PRAGMA] file control returns 1048 ** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means 1049 ** that the VFS encountered an error while handling the [PRAGMA] and the 1050 ** compilation of the PRAGMA fails with an error. ^The [SQLITE_FCNTL_PRAGMA] 1051 ** file control occurs at the beginning of pragma statement analysis and so 1052 ** it is able to override built-in [PRAGMA] statements. 1053 ** 1054 ** <li>[[SQLITE_FCNTL_BUSYHANDLER]] 1055 ** ^The [SQLITE_FCNTL_BUSYHANDLER] 1056 ** file-control may be invoked by SQLite on the database file handle 1057 ** shortly after it is opened in order to provide a custom VFS with access 1058 ** to the connection's busy-handler callback. The argument is of type (void**) 1059 ** - an array of two (void *) values. The first (void *) actually points 1060 ** to a function of type (int (*)(void *)). In order to invoke the connection's 1061 ** busy-handler, this function should be invoked with the second (void *) in 1062 ** the array as the only argument. If it returns non-zero, then the operation 1063 ** should be retried. If it returns zero, the custom VFS should abandon the 1064 ** current operation. 1065 ** 1066 ** <li>[[SQLITE_FCNTL_TEMPFILENAME]] 1067 ** ^Applications can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control 1068 ** to have SQLite generate a 1069 ** temporary filename using the same algorithm that is followed to generate 1070 ** temporary filenames for TEMP tables and other internal uses. The 1071 ** argument should be a char** which will be filled with the filename 1072 ** written into memory obtained from [sqlite3_malloc()]. The caller should 1073 ** invoke [sqlite3_free()] on the result to avoid a memory leak. 1074 ** 1075 ** <li>[[SQLITE_FCNTL_MMAP_SIZE]] 1076 ** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the 1077 ** maximum number of bytes that will be used for memory-mapped I/O. 1078 ** The argument is a pointer to a value of type sqlite3_int64 that 1079 ** is an advisory maximum number of bytes in the file to memory map. The 1080 ** pointer is overwritten with the old value. The limit is not changed if 1081 ** the value originally pointed to is negative, and so the current limit 1082 ** can be queried by passing in a pointer to a negative number. This 1083 ** file-control is used internally to implement [PRAGMA mmap_size]. 1084 ** 1085 ** <li>[[SQLITE_FCNTL_TRACE]] 1086 ** The [SQLITE_FCNTL_TRACE] file control provides advisory information 1087 ** to the VFS about what the higher layers of the SQLite stack are doing. 1088 ** This file control is used by some VFS activity tracing [shims]. 1089 ** The argument is a zero-terminated string. Higher layers in the 1090 ** SQLite stack may generate instances of this file control if 1091 ** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled. 1092 ** 1093 ** <li>[[SQLITE_FCNTL_HAS_MOVED]] 1094 ** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a 1095 ** pointer to an integer and it writes a boolean into that integer depending 1096 ** on whether or not the file has been renamed, moved, or deleted since it 1097 ** was first opened. 1098 ** 1099 ** <li>[[SQLITE_FCNTL_WIN32_GET_HANDLE]] 1100 ** The [SQLITE_FCNTL_WIN32_GET_HANDLE] opcode can be used to obtain the 1101 ** underlying native file handle associated with a file handle. This file 1102 ** control interprets its argument as a pointer to a native file handle and 1103 ** writes the resulting value there. 1104 ** 1105 ** <li>[[SQLITE_FCNTL_WIN32_SET_HANDLE]] 1106 ** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging. This 1107 ** opcode causes the xFileControl method to swap the file handle with the one 1108 ** pointed to by the pArg argument. This capability is used during testing 1109 ** and only needs to be supported when SQLITE_TEST is defined. 1110 ** 1111 ** <li>[[SQLITE_FCNTL_NULL_IO]] 1112 ** The [SQLITE_FCNTL_NULL_IO] opcode sets the low-level file descriptor 1113 ** or file handle for the [sqlite3_file] object such that it will no longer 1114 ** read or write to the database file. 1115 ** 1116 ** <li>[[SQLITE_FCNTL_WAL_BLOCK]] 1117 ** The [SQLITE_FCNTL_WAL_BLOCK] is a signal to the VFS layer that it might 1118 ** be advantageous to block on the next WAL lock if the lock is not immediately 1119 ** available. The WAL subsystem issues this signal during rare 1120 ** circumstances in order to fix a problem with priority inversion. 1121 ** Applications should <em>not</em> use this file-control. 1122 ** 1123 ** <li>[[SQLITE_FCNTL_ZIPVFS]] 1124 ** The [SQLITE_FCNTL_ZIPVFS] opcode is implemented by zipvfs only. All other 1125 ** VFS should return SQLITE_NOTFOUND for this opcode. 1126 ** 1127 ** <li>[[SQLITE_FCNTL_RBU]] 1128 ** The [SQLITE_FCNTL_RBU] opcode is implemented by the special VFS used by 1129 ** the RBU extension only. All other VFS should return SQLITE_NOTFOUND for 1130 ** this opcode. 1131 ** 1132 ** <li>[[SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]] 1133 ** If the [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] opcode returns SQLITE_OK, then 1134 ** the file descriptor is placed in "batch write mode", which 1135 ** means all subsequent write operations will be deferred and done 1136 ** atomically at the next [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]. Systems 1137 ** that do not support batch atomic writes will return SQLITE_NOTFOUND. 1138 ** ^Following a successful SQLITE_FCNTL_BEGIN_ATOMIC_WRITE and prior to 1139 ** the closing [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] or 1140 ** [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE], SQLite will make 1141 ** no VFS interface calls on the same [sqlite3_file] file descriptor 1142 ** except for calls to the xWrite method and the xFileControl method 1143 ** with [SQLITE_FCNTL_SIZE_HINT]. 1144 ** 1145 ** <li>[[SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]] 1146 ** The [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] opcode causes all write 1147 ** operations since the previous successful call to 1148 ** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be performed atomically. 1149 ** This file control returns [SQLITE_OK] if and only if the writes were 1150 ** all performed successfully and have been committed to persistent storage. 1151 ** ^Regardless of whether or not it is successful, this file control takes 1152 ** the file descriptor out of batch write mode so that all subsequent 1153 ** write operations are independent. 1154 ** ^SQLite will never invoke SQLITE_FCNTL_COMMIT_ATOMIC_WRITE without 1155 ** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]. 1156 ** 1157 ** <li>[[SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE]] 1158 ** The [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE] opcode causes all write 1159 ** operations since the previous successful call to 1160 ** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be rolled back. 1161 ** ^This file control takes the file descriptor out of batch write mode 1162 ** so that all subsequent write operations are independent. 1163 ** ^SQLite will never invoke SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE without 1164 ** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]. 1165 ** 1166 ** <li>[[SQLITE_FCNTL_LOCK_TIMEOUT]] 1167 ** The [SQLITE_FCNTL_LOCK_TIMEOUT] opcode is used to configure a VFS 1168 ** to block for up to M milliseconds before failing when attempting to 1169 ** obtain a file lock using the xLock or xShmLock methods of the VFS. 1170 ** The parameter is a pointer to a 32-bit signed integer that contains 1171 ** the value that M is to be set to. Before returning, the 32-bit signed 1172 ** integer is overwritten with the previous value of M. 1173 ** 1174 ** <li>[[SQLITE_FCNTL_BLOCK_ON_CONNECT]] 1175 ** The [SQLITE_FCNTL_BLOCK_ON_CONNECT] opcode is used to configure the 1176 ** VFS to block when taking a SHARED lock to connect to a wal mode database. 1177 ** This is used to implement the functionality associated with 1178 ** SQLITE_SETLK_BLOCK_ON_CONNECT. 1179 ** 1180 ** <li>[[SQLITE_FCNTL_DATA_VERSION]] 1181 ** The [SQLITE_FCNTL_DATA_VERSION] opcode is used to detect changes to 1182 ** a database file. The argument is a pointer to a 32-bit unsigned integer. 1183 ** The "data version" for the pager is written into the pointer. The 1184 ** "data version" changes whenever any change occurs to the corresponding 1185 ** database file, either through SQL statements on the same database 1186 ** connection or through transactions committed by separate database 1187 ** connections possibly in other processes. The [sqlite3_total_changes()] 1188 ** interface can be used to find if any database on the connection has changed, 1189 ** but that interface responds to changes on TEMP as well as MAIN and does 1190 ** not provide a mechanism to detect changes to MAIN only. Also, the 1191 ** [sqlite3_total_changes()] interface responds to internal changes only and 1192 ** omits changes made by other database connections. The 1193 ** [PRAGMA data_version] command provides a mechanism to detect changes to 1194 ** a single attached database that occur due to other database connections, 1195 ** but omits changes implemented by the database connection on which it is 1196 ** called. This file control is the only mechanism to detect changes that 1197 ** happen either internally or externally and that are associated with 1198 ** a particular attached database. 1199 ** 1200 ** <li>[[SQLITE_FCNTL_CKPT_START]] 1201 ** The [SQLITE_FCNTL_CKPT_START] opcode is invoked from within a checkpoint 1202 ** in wal mode before the client starts to copy pages from the wal 1203 ** file to the database file. 1204 ** 1205 ** <li>[[SQLITE_FCNTL_CKPT_DONE]] 1206 ** The [SQLITE_FCNTL_CKPT_DONE] opcode is invoked from within a checkpoint 1207 ** in wal mode after the client has finished copying pages from the wal 1208 ** file to the database file, but before the *-shm file is updated to 1209 ** record the fact that the pages have been checkpointed. 1210 ** 1211 ** <li>[[SQLITE_FCNTL_EXTERNAL_READER]] 1212 ** The EXPERIMENTAL [SQLITE_FCNTL_EXTERNAL_READER] opcode is used to detect 1213 ** whether or not there is a database client in another process with a wal-mode 1214 ** transaction open on the database or not. It is only available on unix. The 1215 ** (void*) argument passed with this file-control should be a pointer to a 1216 ** value of type (int). The integer value is set to 1 if the database is a wal 1217 ** mode database and there exists at least one client in another process that 1218 ** currently has an SQL transaction open on the database. It is set to 0 if 1219 ** the database is not a wal-mode db, or if there is no such connection in any 1220 ** other process. This opcode cannot be used to detect transactions opened 1221 ** by clients within the current process, only within other processes. 1222 ** 1223 ** <li>[[SQLITE_FCNTL_CKSM_FILE]] 1224 ** The [SQLITE_FCNTL_CKSM_FILE] opcode is for use internally by the 1225 ** [checksum VFS shim] only. 1226 ** 1227 ** <li>[[SQLITE_FCNTL_RESET_CACHE]] 1228 ** If there is currently no transaction open on the database, and the 1229 ** database is not a temp db, then the [SQLITE_FCNTL_RESET_CACHE] file-control 1230 ** purges the contents of the in-memory page cache. If there is an open 1231 ** transaction, or if the db is a temp-db, this opcode is a no-op, not an error. 1232 ** 1233 ** <li>[[SQLITE_FCNTL_FILESTAT]] 1234 ** The [SQLITE_FCNTL_FILESTAT] opcode returns low-level diagnostic information 1235 ** about the [sqlite3_file] objects used access the database and journal files 1236 ** for the given schema. The fourth parameter to [sqlite3_file_control()] 1237 ** should be an initialized [sqlite3_str] pointer. JSON text describing 1238 ** various aspects of the sqlite3_file object is appended to the sqlite3_str. 1239 ** The SQLITE_FCNTL_FILESTAT opcode is usually a no-op, unless compile-time 1240 ** options are used to enable it. 1241 ** </ul> 1242 */ 1243 #define SQLITE_FCNTL_LOCKSTATE 1 1244 #define SQLITE_FCNTL_GET_LOCKPROXYFILE 2 1245 #define SQLITE_FCNTL_SET_LOCKPROXYFILE 3 1246 #define SQLITE_FCNTL_LAST_ERRNO 4 1247 #define SQLITE_FCNTL_SIZE_HINT 5 1248 #define SQLITE_FCNTL_CHUNK_SIZE 6 1249 #define SQLITE_FCNTL_FILE_POINTER 7 1250 #define SQLITE_FCNTL_SYNC_OMITTED 8 1251 #define SQLITE_FCNTL_WIN32_AV_RETRY 9 1252 #define SQLITE_FCNTL_PERSIST_WAL 10 1253 #define SQLITE_FCNTL_OVERWRITE 11 1254 #define SQLITE_FCNTL_VFSNAME 12 1255 #define SQLITE_FCNTL_POWERSAFE_OVERWRITE 13 1256 #define SQLITE_FCNTL_PRAGMA 14 1257 #define SQLITE_FCNTL_BUSYHANDLER 15 1258 #define SQLITE_FCNTL_TEMPFILENAME 16 1259 #define SQLITE_FCNTL_MMAP_SIZE 18 1260 #define SQLITE_FCNTL_TRACE 19 1261 #define SQLITE_FCNTL_HAS_MOVED 20 1262 #define SQLITE_FCNTL_SYNC 21 1263 #define SQLITE_FCNTL_COMMIT_PHASETWO 22 1264 #define SQLITE_FCNTL_WIN32_SET_HANDLE 23 1265 #define SQLITE_FCNTL_WAL_BLOCK 24 1266 #define SQLITE_FCNTL_ZIPVFS 25 1267 #define SQLITE_FCNTL_RBU 26 1268 #define SQLITE_FCNTL_VFS_POINTER 27 1269 #define SQLITE_FCNTL_JOURNAL_POINTER 28 1270 #define SQLITE_FCNTL_WIN32_GET_HANDLE 29 1271 #define SQLITE_FCNTL_PDB 30 1272 #define SQLITE_FCNTL_BEGIN_ATOMIC_WRITE 31 1273 #define SQLITE_FCNTL_COMMIT_ATOMIC_WRITE 32 1274 #define SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE 33 1275 #define SQLITE_FCNTL_LOCK_TIMEOUT 34 1276 #define SQLITE_FCNTL_DATA_VERSION 35 1277 #define SQLITE_FCNTL_SIZE_LIMIT 36 1278 #define SQLITE_FCNTL_CKPT_DONE 37 1279 #define SQLITE_FCNTL_RESERVE_BYTES 38 1280 #define SQLITE_FCNTL_CKPT_START 39 1281 #define SQLITE_FCNTL_EXTERNAL_READER 40 1282 #define SQLITE_FCNTL_CKSM_FILE 41 1283 #define SQLITE_FCNTL_RESET_CACHE 42 1284 #define SQLITE_FCNTL_NULL_IO 43 1285 #define SQLITE_FCNTL_BLOCK_ON_CONNECT 44 1286 #define SQLITE_FCNTL_FILESTAT 45 1287 1288 /* deprecated names */ 1289 #define SQLITE_GET_LOCKPROXYFILE SQLITE_FCNTL_GET_LOCKPROXYFILE 1290 #define SQLITE_SET_LOCKPROXYFILE SQLITE_FCNTL_SET_LOCKPROXYFILE 1291 #define SQLITE_LAST_ERRNO SQLITE_FCNTL_LAST_ERRNO 1292 1293 /* reserved file-control numbers: 1294 ** 101 1295 ** 102 1296 ** 103 1297 */ 1298 1299 1300 /* 1301 ** CAPI3REF: Mutex Handle 1302 ** 1303 ** The mutex module within SQLite defines [sqlite3_mutex] to be an 1304 ** abstract type for a mutex object. The SQLite core never looks 1305 ** at the internal representation of an [sqlite3_mutex]. It only 1306 ** deals with pointers to the [sqlite3_mutex] object. 1307 ** 1308 ** Mutexes are created using [sqlite3_mutex_alloc()]. 1309 */ 1310 typedef struct sqlite3_mutex sqlite3_mutex; 1311 1312 /* 1313 ** CAPI3REF: Loadable Extension Thunk 1314 ** 1315 ** A pointer to the opaque sqlite3_api_routines structure is passed as 1316 ** the third parameter to entry points of [loadable extensions]. This 1317 ** structure must be typedefed in order to work around compiler warnings 1318 ** on some platforms. 1319 */ 1320 typedef struct sqlite3_api_routines sqlite3_api_routines; 1321 1322 /* 1323 ** CAPI3REF: File Name 1324 ** 1325 ** Type [sqlite3_filename] is used by SQLite to pass filenames to the 1326 ** xOpen method of a [VFS]. It may be cast to (const char*) and treated 1327 ** as a normal, nul-terminated, UTF-8 buffer containing the filename, but 1328 ** may also be passed to special APIs such as: 1329 ** 1330 ** <ul> 1331 ** <li> sqlite3_filename_database() 1332 ** <li> sqlite3_filename_journal() 1333 ** <li> sqlite3_filename_wal() 1334 ** <li> sqlite3_uri_parameter() 1335 ** <li> sqlite3_uri_boolean() 1336 ** <li> sqlite3_uri_int64() 1337 ** <li> sqlite3_uri_key() 1338 ** </ul> 1339 */ 1340 typedef const char *sqlite3_filename; 1341 1342 /* 1343 ** CAPI3REF: OS Interface Object 1344 ** 1345 ** An instance of the sqlite3_vfs object defines the interface between 1346 ** the SQLite core and the underlying operating system. The "vfs" 1347 ** in the name of the object stands for "virtual file system". See 1348 ** the [VFS | VFS documentation] for further information. 1349 ** 1350 ** The VFS interface is sometimes extended by adding new methods onto 1351 ** the end. Each time such an extension occurs, the iVersion field 1352 ** is incremented. The iVersion value started out as 1 in 1353 ** SQLite [version 3.5.0] on [dateof:3.5.0], then increased to 2 1354 ** with SQLite [version 3.7.0] on [dateof:3.7.0], and then increased 1355 ** to 3 with SQLite [version 3.7.6] on [dateof:3.7.6]. Additional fields 1356 ** may be appended to the sqlite3_vfs object and the iVersion value 1357 ** may increase again in future versions of SQLite. 1358 ** Note that due to an oversight, the structure 1359 ** of the sqlite3_vfs object changed in the transition from 1360 ** SQLite [version 3.5.9] to [version 3.6.0] on [dateof:3.6.0] 1361 ** and yet the iVersion field was not increased. 1362 ** 1363 ** The szOsFile field is the size of the subclassed [sqlite3_file] 1364 ** structure used by this VFS. mxPathname is the maximum length of 1365 ** a pathname in this VFS. 1366 ** 1367 ** Registered sqlite3_vfs objects are kept on a linked list formed by 1368 ** the pNext pointer. The [sqlite3_vfs_register()] 1369 ** and [sqlite3_vfs_unregister()] interfaces manage this list 1370 ** in a thread-safe way. The [sqlite3_vfs_find()] interface 1371 ** searches the list. Neither the application code nor the VFS 1372 ** implementation should use the pNext pointer. 1373 ** 1374 ** The pNext field is the only field in the sqlite3_vfs 1375 ** structure that SQLite will ever modify. SQLite will only access 1376 ** or modify this field while holding a particular static mutex. 1377 ** The application should never modify anything within the sqlite3_vfs 1378 ** object once the object has been registered. 1379 ** 1380 ** The zName field holds the name of the VFS module. The name must 1381 ** be unique across all VFS modules. 1382 ** 1383 ** [[sqlite3_vfs.xOpen]] 1384 ** ^SQLite guarantees that the zFilename parameter to xOpen 1385 ** is either a NULL pointer or string obtained 1386 ** from xFullPathname() with an optional suffix added. 1387 ** ^If a suffix is added to the zFilename parameter, it will 1388 ** consist of a single "-" character followed by no more than 1389 ** 11 alphanumeric and/or "-" characters. 1390 ** ^SQLite further guarantees that 1391 ** the string will be valid and unchanged until xClose() is 1392 ** called. Because of the previous sentence, 1393 ** the [sqlite3_file] can safely store a pointer to the 1394 ** filename if it needs to remember the filename for some reason. 1395 ** If the zFilename parameter to xOpen is a NULL pointer then xOpen 1396 ** must invent its own temporary name for the file. ^Whenever the 1397 ** xFilename parameter is NULL it will also be the case that the 1398 ** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE]. 1399 ** 1400 ** The flags argument to xOpen() includes all bits set in 1401 ** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()] 1402 ** or [sqlite3_open16()] is used, then flags includes at least 1403 ** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. 1404 ** If xOpen() opens a file read-only then it sets *pOutFlags to 1405 ** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set. 1406 ** 1407 ** ^(SQLite will also add one of the following flags to the xOpen() 1408 ** call, depending on the object being opened: 1409 ** 1410 ** <ul> 1411 ** <li> [SQLITE_OPEN_MAIN_DB] 1412 ** <li> [SQLITE_OPEN_MAIN_JOURNAL] 1413 ** <li> [SQLITE_OPEN_TEMP_DB] 1414 ** <li> [SQLITE_OPEN_TEMP_JOURNAL] 1415 ** <li> [SQLITE_OPEN_TRANSIENT_DB] 1416 ** <li> [SQLITE_OPEN_SUBJOURNAL] 1417 ** <li> [SQLITE_OPEN_SUPER_JOURNAL] 1418 ** <li> [SQLITE_OPEN_WAL] 1419 ** </ul>)^ 1420 ** 1421 ** The file I/O implementation can use the object type flags to 1422 ** change the way it deals with files. For example, an application 1423 ** that does not care about crash recovery or rollback might make 1424 ** the open of a journal file a no-op. Writes to this journal would 1425 ** also be no-ops, and any attempt to read the journal would return 1426 ** SQLITE_IOERR. Or the implementation might recognize that a database 1427 ** file will be doing page-aligned sector reads and writes in a random 1428 ** order and set up its I/O subsystem accordingly. 1429 ** 1430 ** SQLite might also add one of the following flags to the xOpen method: 1431 ** 1432 ** <ul> 1433 ** <li> [SQLITE_OPEN_DELETEONCLOSE] 1434 ** <li> [SQLITE_OPEN_EXCLUSIVE] 1435 ** </ul> 1436 ** 1437 ** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be 1438 ** deleted when it is closed. ^The [SQLITE_OPEN_DELETEONCLOSE] 1439 ** will be set for TEMP databases and their journals, transient 1440 ** databases, and subjournals. 1441 ** 1442 ** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction 1443 ** with the [SQLITE_OPEN_CREATE] flag, which are both directly 1444 ** analogous to the O_EXCL and O_CREAT flags of the POSIX open() 1445 ** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the 1446 ** SQLITE_OPEN_CREATE, is used to indicate that file should always 1447 ** be created, and that it is an error if it already exists. 1448 ** It is <i>not</i> used to indicate the file should be opened 1449 ** for exclusive access. 1450 ** 1451 ** ^At least szOsFile bytes of memory are allocated by SQLite 1452 ** to hold the [sqlite3_file] structure passed as the third 1453 ** argument to xOpen. The xOpen method does not have to 1454 ** allocate the structure; it should just fill it in. Note that 1455 ** the xOpen method must set the sqlite3_file.pMethods to either 1456 ** a valid [sqlite3_io_methods] object or to NULL. xOpen must do 1457 ** this even if the open fails. SQLite expects that the sqlite3_file.pMethods 1458 ** element will be valid after xOpen returns regardless of the success 1459 ** or failure of the xOpen call. 1460 ** 1461 ** [[sqlite3_vfs.xAccess]] 1462 ** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS] 1463 ** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to 1464 ** test whether a file is readable and writable, or [SQLITE_ACCESS_READ] 1465 ** to test whether a file is at least readable. The SQLITE_ACCESS_READ 1466 ** flag is never actually used and is not implemented in the built-in 1467 ** VFSes of SQLite. The file is named by the second argument and can be a 1468 ** directory. The xAccess method returns [SQLITE_OK] on success or some 1469 ** non-zero error code if there is an I/O error or if the name of 1470 ** the file given in the second argument is illegal. If SQLITE_OK 1471 ** is returned, then non-zero or zero is written into *pResOut to indicate 1472 ** whether or not the file is accessible. 1473 ** 1474 ** ^SQLite will always allocate at least mxPathname+1 bytes for the 1475 ** output buffer xFullPathname. The exact size of the output buffer 1476 ** is also passed as a parameter to both methods. If the output buffer 1477 ** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is 1478 ** handled as a fatal error by SQLite, vfs implementations should endeavor 1479 ** to prevent this by setting mxPathname to a sufficiently large value. 1480 ** 1481 ** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64() 1482 ** interfaces are not strictly a part of the filesystem, but they are 1483 ** included in the VFS structure for completeness. 1484 ** The xRandomness() function attempts to return nBytes bytes 1485 ** of good-quality randomness into zOut. The return value is 1486 ** the actual number of bytes of randomness obtained. 1487 ** The xSleep() method causes the calling thread to sleep for at 1488 ** least the number of microseconds given. ^The xCurrentTime() 1489 ** method returns a Julian Day Number for the current date and time as 1490 ** a floating point value. 1491 ** ^The xCurrentTimeInt64() method returns, as an integer, the Julian 1492 ** Day Number multiplied by 86400000 (the number of milliseconds in 1493 ** a 24-hour day). 1494 ** ^SQLite will use the xCurrentTimeInt64() method to get the current 1495 ** date and time if that method is available (if iVersion is 2 or 1496 ** greater and the function pointer is not NULL) and will fall back 1497 ** to xCurrentTime() if xCurrentTimeInt64() is unavailable. 1498 ** 1499 ** ^The xSetSystemCall(), xGetSystemCall(), and xNextSystemCall() interfaces 1500 ** are not used by the SQLite core. These optional interfaces are provided 1501 ** by some VFSes to facilitate testing of the VFS code. By overriding 1502 ** system calls with functions under its control, a test program can 1503 ** simulate faults and error conditions that would otherwise be difficult 1504 ** or impossible to induce. The set of system calls that can be overridden 1505 ** varies from one VFS to another, and from one version of the same VFS to the 1506 ** next. Applications that use these interfaces must be prepared for any 1507 ** or all of these interfaces to be NULL or for their behavior to change 1508 ** from one release to the next. Applications must not attempt to access 1509 ** any of these methods if the iVersion of the VFS is less than 3. 1510 */ 1511 typedef struct sqlite3_vfs sqlite3_vfs; 1512 typedef void (*sqlite3_syscall_ptr)(void); 1513 struct sqlite3_vfs { 1514 int iVersion; /* Structure version number (currently 3) */ 1515 int szOsFile; /* Size of subclassed sqlite3_file */ 1516 int mxPathname; /* Maximum file pathname length */ 1517 sqlite3_vfs *pNext; /* Next registered VFS */ 1518 const char *zName; /* Name of this virtual file system */ 1519 void *pAppData; /* Pointer to application-specific data */ 1520 int (*xOpen)(sqlite3_vfs*, sqlite3_filename zName, sqlite3_file*, 1521 int flags, int *pOutFlags); 1522 int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir); 1523 int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut); 1524 int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut); 1525 void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename); 1526 void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg); 1527 void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void); 1528 void (*xDlClose)(sqlite3_vfs*, void*); 1529 int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut); 1530 int (*xSleep)(sqlite3_vfs*, int microseconds); 1531 int (*xCurrentTime)(sqlite3_vfs*, double*); 1532 int (*xGetLastError)(sqlite3_vfs*, int, char *); 1533 /* 1534 ** The methods above are in version 1 of the sqlite_vfs object 1535 ** definition. Those that follow are added in version 2 or later 1536 */ 1537 int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*); 1538 /* 1539 ** The methods above are in versions 1 and 2 of the sqlite_vfs object. 1540 ** Those below are for version 3 and greater. 1541 */ 1542 int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr); 1543 sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName); 1544 const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName); 1545 /* 1546 ** The methods above are in versions 1 through 3 of the sqlite_vfs object. 1547 ** New fields may be appended in future versions. The iVersion 1548 ** value will increment whenever this happens. 1549 */ 1550 }; 1551 1552 /* 1553 ** CAPI3REF: Flags for the xAccess VFS method 1554 ** 1555 ** These integer constants can be used as the third parameter to 1556 ** the xAccess method of an [sqlite3_vfs] object. They determine 1557 ** what kind of permissions the xAccess method is looking for. 1558 ** With SQLITE_ACCESS_EXISTS, the xAccess method 1559 ** simply checks whether the file exists. 1560 ** With SQLITE_ACCESS_READWRITE, the xAccess method 1561 ** checks whether the named directory is both readable and writable 1562 ** (in other words, if files can be added, removed, and renamed within 1563 ** the directory). 1564 ** The SQLITE_ACCESS_READWRITE constant is currently used only by the 1565 ** [temp_store_directory pragma], though this could change in a future 1566 ** release of SQLite. 1567 ** With SQLITE_ACCESS_READ, the xAccess method 1568 ** checks whether the file is readable. The SQLITE_ACCESS_READ constant is 1569 ** currently unused, though it might be used in a future release of 1570 ** SQLite. 1571 */ 1572 #define SQLITE_ACCESS_EXISTS 0 1573 #define SQLITE_ACCESS_READWRITE 1 /* Used by PRAGMA temp_store_directory */ 1574 #define SQLITE_ACCESS_READ 2 /* Unused */ 1575 1576 /* 1577 ** CAPI3REF: Flags for the xShmLock VFS method 1578 ** 1579 ** These integer constants define the various locking operations 1580 ** allowed by the xShmLock method of [sqlite3_io_methods]. The 1581 ** following are the only legal combinations of flags to the 1582 ** xShmLock method: 1583 ** 1584 ** <ul> 1585 ** <li> SQLITE_SHM_LOCK | SQLITE_SHM_SHARED 1586 ** <li> SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE 1587 ** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED 1588 ** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE 1589 ** </ul> 1590 ** 1591 ** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as 1592 ** was given on the corresponding lock. 1593 ** 1594 ** The xShmLock method can transition between unlocked and SHARED or 1595 ** between unlocked and EXCLUSIVE. It cannot transition between SHARED 1596 ** and EXCLUSIVE. 1597 */ 1598 #define SQLITE_SHM_UNLOCK 1 1599 #define SQLITE_SHM_LOCK 2 1600 #define SQLITE_SHM_SHARED 4 1601 #define SQLITE_SHM_EXCLUSIVE 8 1602 1603 /* 1604 ** CAPI3REF: Maximum xShmLock index 1605 ** 1606 ** The xShmLock method on [sqlite3_io_methods] may use values 1607 ** between 0 and this upper bound as its "offset" argument. 1608 ** The SQLite core will never attempt to acquire or release a 1609 ** lock outside of this range 1610 */ 1611 #define SQLITE_SHM_NLOCK 8 1612 1613 1614 /* 1615 ** CAPI3REF: Initialize The SQLite Library 1616 ** 1617 ** ^The sqlite3_initialize() routine initializes the 1618 ** SQLite library. ^The sqlite3_shutdown() routine 1619 ** deallocates any resources that were allocated by sqlite3_initialize(). 1620 ** These routines are designed to aid in process initialization and 1621 ** shutdown on embedded systems. Workstation applications using 1622 ** SQLite normally do not need to invoke either of these routines. 1623 ** 1624 ** A call to sqlite3_initialize() is an "effective" call if it is 1625 ** the first time sqlite3_initialize() is invoked during the lifetime of 1626 ** the process, or if it is the first time sqlite3_initialize() is invoked 1627 ** following a call to sqlite3_shutdown(). ^(Only an effective call 1628 ** of sqlite3_initialize() does any initialization. All other calls 1629 ** are harmless no-ops.)^ 1630 ** 1631 ** A call to sqlite3_shutdown() is an "effective" call if it is the first 1632 ** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only 1633 ** an effective call to sqlite3_shutdown() does any deinitialization. 1634 ** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^ 1635 ** 1636 ** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown() 1637 ** is not. The sqlite3_shutdown() interface must only be called from a 1638 ** single thread. All open [database connections] must be closed and all 1639 ** other SQLite resources must be deallocated prior to invoking 1640 ** sqlite3_shutdown(). 1641 ** 1642 ** Among other things, ^sqlite3_initialize() will invoke 1643 ** sqlite3_os_init(). Similarly, ^sqlite3_shutdown() 1644 ** will invoke sqlite3_os_end(). 1645 ** 1646 ** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success. 1647 ** ^If for some reason, sqlite3_initialize() is unable to initialize 1648 ** the library (perhaps it is unable to allocate a needed resource such 1649 ** as a mutex) it returns an [error code] other than [SQLITE_OK]. 1650 ** 1651 ** ^The sqlite3_initialize() routine is called internally by many other 1652 ** SQLite interfaces so that an application usually does not need to 1653 ** invoke sqlite3_initialize() directly. For example, [sqlite3_open()] 1654 ** calls sqlite3_initialize() so the SQLite library will be automatically 1655 ** initialized when [sqlite3_open()] is called if it has not been initialized 1656 ** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT] 1657 ** compile-time option, then the automatic calls to sqlite3_initialize() 1658 ** are omitted and the application must call sqlite3_initialize() directly 1659 ** prior to using any other SQLite interface. For maximum portability, 1660 ** it is recommended that applications always invoke sqlite3_initialize() 1661 ** directly prior to using any other SQLite interface. Future releases 1662 ** of SQLite may require this. In other words, the behavior exhibited 1663 ** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the 1664 ** default behavior in some future release of SQLite. 1665 ** 1666 ** The sqlite3_os_init() routine does operating-system specific 1667 ** initialization of the SQLite library. The sqlite3_os_end() 1668 ** routine undoes the effect of sqlite3_os_init(). Typical tasks 1669 ** performed by these routines include allocation or deallocation 1670 ** of static resources, initialization of global variables, 1671 ** setting up a default [sqlite3_vfs] module, or setting up 1672 ** a default configuration using [sqlite3_config()]. 1673 ** 1674 ** The application should never invoke either sqlite3_os_init() 1675 ** or sqlite3_os_end() directly. The application should only invoke 1676 ** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init() 1677 ** interface is called automatically by sqlite3_initialize() and 1678 ** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate 1679 ** implementations for sqlite3_os_init() and sqlite3_os_end() 1680 ** are built into SQLite when it is compiled for Unix, Windows, or OS/2. 1681 ** When [custom builds | built for other platforms] 1682 ** (using the [SQLITE_OS_OTHER=1] compile-time 1683 ** option) the application must supply a suitable implementation for 1684 ** sqlite3_os_init() and sqlite3_os_end(). An application-supplied 1685 ** implementation of sqlite3_os_init() or sqlite3_os_end() 1686 ** must return [SQLITE_OK] on success and some other [error code] upon 1687 ** failure. 1688 */ 1689 SQLITE_API int sqlite3_initialize(void); 1690 SQLITE_API int sqlite3_shutdown(void); 1691 SQLITE_API int sqlite3_os_init(void); 1692 SQLITE_API int sqlite3_os_end(void); 1693 1694 /* 1695 ** CAPI3REF: Configuring The SQLite Library 1696 ** 1697 ** The sqlite3_config() interface is used to make global configuration 1698 ** changes to SQLite in order to tune SQLite to the specific needs of 1699 ** the application. The default configuration is recommended for most 1700 ** applications and so this routine is usually not necessary. It is 1701 ** provided to support rare applications with unusual needs. 1702 ** 1703 ** <b>The sqlite3_config() interface is not threadsafe. The application 1704 ** must ensure that no other SQLite interfaces are invoked by other 1705 ** threads while sqlite3_config() is running.</b> 1706 ** 1707 ** The first argument to sqlite3_config() is an integer 1708 ** [configuration option] that determines 1709 ** what property of SQLite is to be configured. Subsequent arguments 1710 ** vary depending on the [configuration option] 1711 ** in the first argument. 1712 ** 1713 ** For most configuration options, the sqlite3_config() interface 1714 ** may only be invoked prior to library initialization using 1715 ** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()]. 1716 ** The exceptional configuration options that may be invoked at any time 1717 ** are called "anytime configuration options". 1718 ** ^If sqlite3_config() is called after [sqlite3_initialize()] and before 1719 ** [sqlite3_shutdown()] with a first argument that is not an anytime 1720 ** configuration option, then the sqlite3_config() call will 1721 ** return SQLITE_MISUSE. 1722 ** Note, however, that ^sqlite3_config() can be called as part of the 1723 ** implementation of an application-defined [sqlite3_os_init()]. 1724 ** 1725 ** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK]. 1726 ** ^If the option is unknown or SQLite is unable to set the option 1727 ** then this routine returns a non-zero [error code]. 1728 */ 1729 SQLITE_API int sqlite3_config(int, ...); 1730 1731 /* 1732 ** CAPI3REF: Configure database connections 1733 ** METHOD: sqlite3 1734 ** 1735 ** The sqlite3_db_config() interface is used to make configuration 1736 ** changes to a [database connection]. The interface is similar to 1737 ** [sqlite3_config()] except that the changes apply to a single 1738 ** [database connection] (specified in the first argument). 1739 ** 1740 ** The second argument to sqlite3_db_config(D,V,...) is the 1741 ** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code 1742 ** that indicates what aspect of the [database connection] is being configured. 1743 ** Subsequent arguments vary depending on the configuration verb. 1744 ** 1745 ** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if 1746 ** the call is considered successful. 1747 */ 1748 SQLITE_API int sqlite3_db_config(sqlite3*, int op, ...); 1749 1750 /* 1751 ** CAPI3REF: Memory Allocation Routines 1752 ** 1753 ** An instance of this object defines the interface between SQLite 1754 ** and low-level memory allocation routines. 1755 ** 1756 ** This object is used in only one place in the SQLite interface. 1757 ** A pointer to an instance of this object is the argument to 1758 ** [sqlite3_config()] when the configuration option is 1759 ** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC]. 1760 ** By creating an instance of this object 1761 ** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC]) 1762 ** during configuration, an application can specify an alternative 1763 ** memory allocation subsystem for SQLite to use for all of its 1764 ** dynamic memory needs. 1765 ** 1766 ** Note that SQLite comes with several [built-in memory allocators] 1767 ** that are perfectly adequate for the overwhelming majority of applications 1768 ** and that this object is only useful to a tiny minority of applications 1769 ** with specialized memory allocation requirements. This object is 1770 ** also used during testing of SQLite in order to specify an alternative 1771 ** memory allocator that simulates memory out-of-memory conditions in 1772 ** order to verify that SQLite recovers gracefully from such 1773 ** conditions. 1774 ** 1775 ** The xMalloc, xRealloc, and xFree methods must work like the 1776 ** malloc(), realloc() and free() functions from the standard C library. 1777 ** ^SQLite guarantees that the second argument to 1778 ** xRealloc is always a value returned by a prior call to xRoundup. 1779 ** 1780 ** xSize should return the allocated size of a memory allocation 1781 ** previously obtained from xMalloc or xRealloc. The allocated size 1782 ** is always at least as big as the requested size but may be larger. 1783 ** 1784 ** The xRoundup method returns what would be the allocated size of 1785 ** a memory allocation given a particular requested size. Most memory 1786 ** allocators round up memory allocations at least to the next multiple 1787 ** of 8. Some allocators round up to a larger multiple or to a power of 2. 1788 ** Every memory allocation request coming in through [sqlite3_malloc()] 1789 ** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0, 1790 ** that causes the corresponding memory allocation to fail. 1791 ** 1792 ** The xInit method initializes the memory allocator. For example, 1793 ** it might allocate any required mutexes or initialize internal data 1794 ** structures. The xShutdown method is invoked (indirectly) by 1795 ** [sqlite3_shutdown()] and should deallocate any resources acquired 1796 ** by xInit. The pAppData pointer is used as the only parameter to 1797 ** xInit and xShutdown. 1798 ** 1799 ** SQLite holds the [SQLITE_MUTEX_STATIC_MAIN] mutex when it invokes 1800 ** the xInit method, so the xInit method need not be threadsafe. The 1801 ** xShutdown method is only called from [sqlite3_shutdown()] so it does 1802 ** not need to be threadsafe either. For all other methods, SQLite 1803 ** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the 1804 ** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which 1805 ** it is by default) and so the methods are automatically serialized. 1806 ** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other 1807 ** methods must be threadsafe or else make their own arrangements for 1808 ** serialization. 1809 ** 1810 ** SQLite will never invoke xInit() more than once without an intervening 1811 ** call to xShutdown(). 1812 */ 1813 typedef struct sqlite3_mem_methods sqlite3_mem_methods; 1814 struct sqlite3_mem_methods { 1815 void *(*xMalloc)(int); /* Memory allocation function */ 1816 void (*xFree)(void*); /* Free a prior allocation */ 1817 void *(*xRealloc)(void*,int); /* Resize an allocation */ 1818 int (*xSize)(void*); /* Return the size of an allocation */ 1819 int (*xRoundup)(int); /* Round up request size to allocation size */ 1820 int (*xInit)(void*); /* Initialize the memory allocator */ 1821 void (*xShutdown)(void*); /* Deinitialize the memory allocator */ 1822 void *pAppData; /* Argument to xInit() and xShutdown() */ 1823 }; 1824 1825 /* 1826 ** CAPI3REF: Configuration Options 1827 ** KEYWORDS: {configuration option} 1828 ** 1829 ** These constants are the available integer configuration options that 1830 ** can be passed as the first argument to the [sqlite3_config()] interface. 1831 ** 1832 ** Most of the configuration options for sqlite3_config() 1833 ** will only work if invoked prior to [sqlite3_initialize()] or after 1834 ** [sqlite3_shutdown()]. The few exceptions to this rule are called 1835 ** "anytime configuration options". 1836 ** ^Calling [sqlite3_config()] with a first argument that is not an 1837 ** anytime configuration option in between calls to [sqlite3_initialize()] and 1838 ** [sqlite3_shutdown()] is a no-op that returns SQLITE_MISUSE. 1839 ** 1840 ** The set of anytime configuration options can change (by insertions 1841 ** and/or deletions) from one release of SQLite to the next. 1842 ** As of SQLite version 3.42.0, the complete set of anytime configuration 1843 ** options is: 1844 ** <ul> 1845 ** <li> SQLITE_CONFIG_LOG 1846 ** <li> SQLITE_CONFIG_PCACHE_HDRSZ 1847 ** </ul> 1848 ** 1849 ** New configuration options may be added in future releases of SQLite. 1850 ** Existing configuration options might be discontinued. Applications 1851 ** should check the return code from [sqlite3_config()] to make sure that 1852 ** the call worked. The [sqlite3_config()] interface will return a 1853 ** non-zero [error code] if a discontinued or unsupported configuration option 1854 ** is invoked. 1855 ** 1856 ** <dl> 1857 ** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt> 1858 ** <dd>There are no arguments to this option. ^This option sets the 1859 ** [threading mode] to Single-thread. In other words, it disables 1860 ** all mutexing and puts SQLite into a mode where it can only be used 1861 ** by a single thread. ^If SQLite is compiled with 1862 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1863 ** it is not possible to change the [threading mode] from its default 1864 ** value of Single-thread and so [sqlite3_config()] will return 1865 ** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD 1866 ** configuration option.</dd> 1867 ** 1868 ** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt> 1869 ** <dd>There are no arguments to this option. ^This option sets the 1870 ** [threading mode] to Multi-thread. In other words, it disables 1871 ** mutexing on [database connection] and [prepared statement] objects. 1872 ** The application is responsible for serializing access to 1873 ** [database connections] and [prepared statements]. But other mutexes 1874 ** are enabled so that SQLite will be safe to use in a multi-threaded 1875 ** environment as long as no two threads attempt to use the same 1876 ** [database connection] at the same time. ^If SQLite is compiled with 1877 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1878 ** it is not possible to set the Multi-thread [threading mode] and 1879 ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the 1880 ** SQLITE_CONFIG_MULTITHREAD configuration option.</dd> 1881 ** 1882 ** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt> 1883 ** <dd>There are no arguments to this option. ^This option sets the 1884 ** [threading mode] to Serialized. In other words, this option enables 1885 ** all mutexes including the recursive 1886 ** mutexes on [database connection] and [prepared statement] objects. 1887 ** In this mode (which is the default when SQLite is compiled with 1888 ** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access 1889 ** to [database connections] and [prepared statements] so that the 1890 ** application is free to use the same [database connection] or the 1891 ** same [prepared statement] in different threads at the same time. 1892 ** ^If SQLite is compiled with 1893 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1894 ** it is not possible to set the Serialized [threading mode] and 1895 ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the 1896 ** SQLITE_CONFIG_SERIALIZED configuration option.</dd> 1897 ** 1898 ** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt> 1899 ** <dd> ^(The SQLITE_CONFIG_MALLOC option takes a single argument which is 1900 ** a pointer to an instance of the [sqlite3_mem_methods] structure. 1901 ** The argument specifies 1902 ** alternative low-level memory allocation routines to be used in place of 1903 ** the memory allocation routines built into SQLite.)^ ^SQLite makes 1904 ** its own private copy of the content of the [sqlite3_mem_methods] structure 1905 ** before the [sqlite3_config()] call returns.</dd> 1906 ** 1907 ** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt> 1908 ** <dd> ^(The SQLITE_CONFIG_GETMALLOC option takes a single argument which 1909 ** is a pointer to an instance of the [sqlite3_mem_methods] structure. 1910 ** The [sqlite3_mem_methods] 1911 ** structure is filled with the currently defined memory allocation routines.)^ 1912 ** This option can be used to overload the default memory allocation 1913 ** routines with a wrapper that simulates memory allocation failure or 1914 ** tracks memory usage, for example. </dd> 1915 ** 1916 ** [[SQLITE_CONFIG_SMALL_MALLOC]] <dt>SQLITE_CONFIG_SMALL_MALLOC</dt> 1917 ** <dd> ^The SQLITE_CONFIG_SMALL_MALLOC option takes a single argument of 1918 ** type int, interpreted as a boolean, which if true provides a hint to 1919 ** SQLite that it should avoid large memory allocations if possible. 1920 ** SQLite will run faster if it is free to make large memory allocations, 1921 ** but some applications might prefer to run slower in exchange for 1922 ** guarantees about memory fragmentation that are possible if large 1923 ** allocations are avoided. This hint is normally off. 1924 ** </dd> 1925 ** 1926 ** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt> 1927 ** <dd> ^The SQLITE_CONFIG_MEMSTATUS option takes a single argument of type int, 1928 ** interpreted as a boolean, which enables or disables the collection of 1929 ** memory allocation statistics. ^(When memory allocation statistics are 1930 ** disabled, the following SQLite interfaces become non-operational: 1931 ** <ul> 1932 ** <li> [sqlite3_hard_heap_limit64()] 1933 ** <li> [sqlite3_memory_used()] 1934 ** <li> [sqlite3_memory_highwater()] 1935 ** <li> [sqlite3_soft_heap_limit64()] 1936 ** <li> [sqlite3_status64()] 1937 ** </ul>)^ 1938 ** ^Memory allocation statistics are enabled by default unless SQLite is 1939 ** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory 1940 ** allocation statistics are disabled by default. 1941 ** </dd> 1942 ** 1943 ** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt> 1944 ** <dd> The SQLITE_CONFIG_SCRATCH option is no longer used. 1945 ** </dd> 1946 ** 1947 ** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt> 1948 ** <dd> ^The SQLITE_CONFIG_PAGECACHE option specifies a memory pool 1949 ** that SQLite can use for the database page cache with the default page 1950 ** cache implementation. 1951 ** This configuration option is a no-op if an application-defined page 1952 ** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2]. 1953 ** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to 1954 ** 8-byte aligned memory (pMem), the size of each page cache line (sz), 1955 ** and the number of cache lines (N). 1956 ** The sz argument should be the size of the largest database page 1957 ** (a power of two between 512 and 65536) plus some extra bytes for each 1958 ** page header. ^The number of extra bytes needed by the page header 1959 ** can be determined using [SQLITE_CONFIG_PCACHE_HDRSZ]. 1960 ** ^It is harmless, apart from the wasted memory, 1961 ** for the sz parameter to be larger than necessary. The pMem 1962 ** argument must be either a NULL pointer or a pointer to an 8-byte 1963 ** aligned block of memory of at least sz*N bytes, otherwise 1964 ** subsequent behavior is undefined. 1965 ** ^When pMem is not NULL, SQLite will strive to use the memory provided 1966 ** to satisfy page cache needs, falling back to [sqlite3_malloc()] if 1967 ** a page cache line is larger than sz bytes or if all of the pMem buffer 1968 ** is exhausted. 1969 ** ^If pMem is NULL and N is non-zero, then each database connection 1970 ** does an initial bulk allocation for page cache memory 1971 ** from [sqlite3_malloc()] sufficient for N cache lines if N is positive or 1972 ** of -1024*N bytes if N is negative. ^If additional 1973 ** page cache memory is needed beyond what is provided by the initial 1974 ** allocation, then SQLite goes to [sqlite3_malloc()] separately for each 1975 ** additional cache line. </dd> 1976 ** 1977 ** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt> 1978 ** <dd> ^The SQLITE_CONFIG_HEAP option specifies a static memory buffer 1979 ** that SQLite will use for all of its dynamic memory allocation needs 1980 ** beyond those provided for by [SQLITE_CONFIG_PAGECACHE]. 1981 ** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled 1982 ** with either [SQLITE_ENABLE_MEMSYS3] or [SQLITE_ENABLE_MEMSYS5] and returns 1983 ** [SQLITE_ERROR] if invoked otherwise. 1984 ** ^There are three arguments to SQLITE_CONFIG_HEAP: 1985 ** An 8-byte aligned pointer to the memory, 1986 ** the number of bytes in the memory buffer, and the minimum allocation size. 1987 ** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts 1988 ** to using its default memory allocator (the system malloc() implementation), 1989 ** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the 1990 ** memory pointer is not NULL then the alternative memory 1991 ** allocator is engaged to handle all of SQLites memory allocation needs. 1992 ** The first pointer (the memory pointer) must be aligned to an 8-byte 1993 ** boundary or subsequent behavior of SQLite will be undefined. 1994 ** The minimum allocation size is capped at 2**12. Reasonable values 1995 ** for the minimum allocation size are 2**5 through 2**8.</dd> 1996 ** 1997 ** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt> 1998 ** <dd> ^(The SQLITE_CONFIG_MUTEX option takes a single argument which is a 1999 ** pointer to an instance of the [sqlite3_mutex_methods] structure. 2000 ** The argument specifies alternative low-level mutex routines to be used 2001 ** in place of the mutex routines built into SQLite.)^ ^SQLite makes a copy of 2002 ** the content of the [sqlite3_mutex_methods] structure before the call to 2003 ** [sqlite3_config()] returns. ^If SQLite is compiled with 2004 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 2005 ** the entire mutexing subsystem is omitted from the build and hence calls to 2006 ** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will 2007 ** return [SQLITE_ERROR].</dd> 2008 ** 2009 ** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt> 2010 ** <dd> ^(The SQLITE_CONFIG_GETMUTEX option takes a single argument which 2011 ** is a pointer to an instance of the [sqlite3_mutex_methods] structure. The 2012 ** [sqlite3_mutex_methods] 2013 ** structure is filled with the currently defined mutex routines.)^ 2014 ** This option can be used to overload the default mutex allocation 2015 ** routines with a wrapper used to track mutex usage for performance 2016 ** profiling or testing, for example. ^If SQLite is compiled with 2017 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 2018 ** the entire mutexing subsystem is omitted from the build and hence calls to 2019 ** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will 2020 ** return [SQLITE_ERROR].</dd> 2021 ** 2022 ** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt> 2023 ** <dd> ^(The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine 2024 ** the default size of [lookaside memory] on each [database connection]. 2025 ** The first argument is the 2026 ** size of each lookaside buffer slot ("sz") and the second is the number of 2027 ** slots allocated to each database connection ("cnt").)^ 2028 ** ^(SQLITE_CONFIG_LOOKASIDE sets the <i>default</i> lookaside size. 2029 ** The [SQLITE_DBCONFIG_LOOKASIDE] option to [sqlite3_db_config()] can 2030 ** be used to change the lookaside configuration on individual connections.)^ 2031 ** The [-DSQLITE_DEFAULT_LOOKASIDE] option can be used to change the 2032 ** default lookaside configuration at compile-time. 2033 ** </dd> 2034 ** 2035 ** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt> 2036 ** <dd> ^(The SQLITE_CONFIG_PCACHE2 option takes a single argument which is 2037 ** a pointer to an [sqlite3_pcache_methods2] object. This object specifies 2038 ** the interface to a custom page cache implementation.)^ 2039 ** ^SQLite makes a copy of the [sqlite3_pcache_methods2] object.</dd> 2040 ** 2041 ** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt> 2042 ** <dd> ^(The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which 2043 ** is a pointer to an [sqlite3_pcache_methods2] object. SQLite copies off 2044 ** the current page cache implementation into that object.)^ </dd> 2045 ** 2046 ** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt> 2047 ** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite 2048 ** global [error log]. 2049 ** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a 2050 ** function with a call signature of void(*)(void*,int,const char*), 2051 ** and a pointer to void. ^If the function pointer is not NULL, it is 2052 ** invoked by [sqlite3_log()] to process each logging event. ^If the 2053 ** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op. 2054 ** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is 2055 ** passed through as the first parameter to the application-defined logger 2056 ** function whenever that function is invoked. ^The second parameter to 2057 ** the logger function is a copy of the first parameter to the corresponding 2058 ** [sqlite3_log()] call and is intended to be a [result code] or an 2059 ** [extended result code]. ^The third parameter passed to the logger is 2060 ** a log message after formatting via [sqlite3_snprintf()]. 2061 ** The SQLite logging interface is not reentrant; the logger function 2062 ** supplied by the application must not invoke any SQLite interface. 2063 ** In a multi-threaded application, the application-defined logger 2064 ** function must be threadsafe. </dd> 2065 ** 2066 ** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI 2067 ** <dd>^(The SQLITE_CONFIG_URI option takes a single argument of type int. 2068 ** If non-zero, then URI handling is globally enabled. If the parameter is zero, 2069 ** then URI handling is globally disabled.)^ ^If URI handling is globally 2070 ** enabled, all filenames passed to [sqlite3_open()], [sqlite3_open_v2()], 2071 ** [sqlite3_open16()] or 2072 ** specified as part of [ATTACH] commands are interpreted as URIs, regardless 2073 ** of whether or not the [SQLITE_OPEN_URI] flag is set when the database 2074 ** connection is opened. ^If it is globally disabled, filenames are 2075 ** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the 2076 ** database connection is opened. ^(By default, URI handling is globally 2077 ** disabled. The default value may be changed by compiling with the 2078 ** [SQLITE_USE_URI] symbol defined.)^ 2079 ** 2080 ** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN 2081 ** <dd>^The SQLITE_CONFIG_COVERING_INDEX_SCAN option takes a single integer 2082 ** argument which is interpreted as a boolean in order to enable or disable 2083 ** the use of covering indices for full table scans in the query optimizer. 2084 ** ^The default setting is determined 2085 ** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on" 2086 ** if that compile-time option is omitted. 2087 ** The ability to disable the use of covering indices for full table scans 2088 ** is because some incorrectly coded legacy applications might malfunction 2089 ** when the optimization is enabled. Providing the ability to 2090 ** disable the optimization allows the older, buggy application code to work 2091 ** without change even with newer versions of SQLite. 2092 ** 2093 ** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]] 2094 ** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE 2095 ** <dd> These options are obsolete and should not be used by new code. 2096 ** They are retained for backwards compatibility but are now no-ops. 2097 ** </dd> 2098 ** 2099 ** [[SQLITE_CONFIG_SQLLOG]] 2100 ** <dt>SQLITE_CONFIG_SQLLOG 2101 ** <dd>This option is only available if sqlite is compiled with the 2102 ** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should 2103 ** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int). 2104 ** The second should be of type (void*). The callback is invoked by the library 2105 ** in three separate circumstances, identified by the value passed as the 2106 ** fourth parameter. If the fourth parameter is 0, then the database connection 2107 ** passed as the second argument has just been opened. The third argument 2108 ** points to a buffer containing the name of the main database file. If the 2109 ** fourth parameter is 1, then the SQL statement that the third parameter 2110 ** points to has just been executed. Or, if the fourth parameter is 2, then 2111 ** the connection being passed as the second parameter is being closed. The 2112 ** third parameter is passed NULL In this case. An example of using this 2113 ** configuration option can be seen in the "test_sqllog.c" source file in 2114 ** the canonical SQLite source tree.</dd> 2115 ** 2116 ** [[SQLITE_CONFIG_MMAP_SIZE]] 2117 ** <dt>SQLITE_CONFIG_MMAP_SIZE 2118 ** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values 2119 ** that are the default mmap size limit (the default setting for 2120 ** [PRAGMA mmap_size]) and the maximum allowed mmap size limit. 2121 ** ^The default setting can be overridden by each database connection using 2122 ** either the [PRAGMA mmap_size] command, or by using the 2123 ** [SQLITE_FCNTL_MMAP_SIZE] file control. ^(The maximum allowed mmap size 2124 ** will be silently truncated if necessary so that it does not exceed the 2125 ** compile-time maximum mmap size set by the 2126 ** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^ 2127 ** ^If either argument to this option is negative, then that argument is 2128 ** changed to its compile-time default. 2129 ** 2130 ** [[SQLITE_CONFIG_WIN32_HEAPSIZE]] 2131 ** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE 2132 ** <dd>^The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is 2133 ** compiled for Windows with the [SQLITE_WIN32_MALLOC] pre-processor macro 2134 ** defined. ^SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value 2135 ** that specifies the maximum size of the created heap. 2136 ** 2137 ** [[SQLITE_CONFIG_PCACHE_HDRSZ]] 2138 ** <dt>SQLITE_CONFIG_PCACHE_HDRSZ 2139 ** <dd>^The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which 2140 ** is a pointer to an integer and writes into that integer the number of extra 2141 ** bytes per page required for each page in [SQLITE_CONFIG_PAGECACHE]. 2142 ** The amount of extra space required can change depending on the compiler, 2143 ** target platform, and SQLite version. 2144 ** 2145 ** [[SQLITE_CONFIG_PMASZ]] 2146 ** <dt>SQLITE_CONFIG_PMASZ 2147 ** <dd>^The SQLITE_CONFIG_PMASZ option takes a single parameter which 2148 ** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded 2149 ** sorter to that integer. The default minimum PMA Size is set by the 2150 ** [SQLITE_SORTER_PMASZ] compile-time option. New threads are launched 2151 ** to help with sort operations when multithreaded sorting 2152 ** is enabled (using the [PRAGMA threads] command) and the amount of content 2153 ** to be sorted exceeds the page size times the minimum of the 2154 ** [PRAGMA cache_size] setting and this value. 2155 ** 2156 ** [[SQLITE_CONFIG_STMTJRNL_SPILL]] 2157 ** <dt>SQLITE_CONFIG_STMTJRNL_SPILL 2158 ** <dd>^The SQLITE_CONFIG_STMTJRNL_SPILL option takes a single parameter which 2159 ** becomes the [statement journal] spill-to-disk threshold. 2160 ** [Statement journals] are held in memory until their size (in bytes) 2161 ** exceeds this threshold, at which point they are written to disk. 2162 ** Or if the threshold is -1, statement journals are always held 2163 ** exclusively in memory. 2164 ** Since many statement journals never become large, setting the spill 2165 ** threshold to a value such as 64KiB can greatly reduce the amount of 2166 ** I/O required to support statement rollback. 2167 ** The default value for this setting is controlled by the 2168 ** [SQLITE_STMTJRNL_SPILL] compile-time option. 2169 ** 2170 ** [[SQLITE_CONFIG_SORTERREF_SIZE]] 2171 ** <dt>SQLITE_CONFIG_SORTERREF_SIZE 2172 ** <dd>The SQLITE_CONFIG_SORTERREF_SIZE option accepts a single parameter 2173 ** of type (int) - the new value of the sorter-reference size threshold. 2174 ** Usually, when SQLite uses an external sort to order records according 2175 ** to an ORDER BY clause, all fields required by the caller are present in the 2176 ** sorted records. However, if SQLite determines based on the declared type 2177 ** of a table column that its values are likely to be very large - larger 2178 ** than the configured sorter-reference size threshold - then a reference 2179 ** is stored in each sorted record and the required column values loaded 2180 ** from the database as records are returned in sorted order. The default 2181 ** value for this option is to never use this optimization. Specifying a 2182 ** negative value for this option restores the default behavior. 2183 ** This option is only available if SQLite is compiled with the 2184 ** [SQLITE_ENABLE_SORTER_REFERENCES] compile-time option. 2185 ** 2186 ** [[SQLITE_CONFIG_MEMDB_MAXSIZE]] 2187 ** <dt>SQLITE_CONFIG_MEMDB_MAXSIZE 2188 ** <dd>The SQLITE_CONFIG_MEMDB_MAXSIZE option accepts a single parameter 2189 ** [sqlite3_int64] parameter which is the default maximum size for an in-memory 2190 ** database created using [sqlite3_deserialize()]. This default maximum 2191 ** size can be adjusted up or down for individual databases using the 2192 ** [SQLITE_FCNTL_SIZE_LIMIT] [sqlite3_file_control|file-control]. If this 2193 ** configuration setting is never used, then the default maximum is determined 2194 ** by the [SQLITE_MEMDB_DEFAULT_MAXSIZE] compile-time option. If that 2195 ** compile-time option is not set, then the default maximum is 1073741824. 2196 ** 2197 ** [[SQLITE_CONFIG_ROWID_IN_VIEW]] 2198 ** <dt>SQLITE_CONFIG_ROWID_IN_VIEW 2199 ** <dd>The SQLITE_CONFIG_ROWID_IN_VIEW option enables or disables the ability 2200 ** for VIEWs to have a ROWID. The capability can only be enabled if SQLite is 2201 ** compiled with -DSQLITE_ALLOW_ROWID_IN_VIEW, in which case the capability 2202 ** defaults to on. This configuration option queries the current setting or 2203 ** changes the setting to off or on. The argument is a pointer to an integer. 2204 ** If that integer initially holds a value of 1, then the ability for VIEWs to 2205 ** have ROWIDs is activated. If the integer initially holds zero, then the 2206 ** ability is deactivated. Any other initial value for the integer leaves the 2207 ** setting unchanged. After changes, if any, the integer is written with 2208 ** a 1 or 0, if the ability for VIEWs to have ROWIDs is on or off. If SQLite 2209 ** is compiled without -DSQLITE_ALLOW_ROWID_IN_VIEW (which is the usual and 2210 ** recommended case) then the integer is always filled with zero, regardless 2211 ** if its initial value. 2212 ** </dl> 2213 */ 2214 #define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */ 2215 #define SQLITE_CONFIG_MULTITHREAD 2 /* nil */ 2216 #define SQLITE_CONFIG_SERIALIZED 3 /* nil */ 2217 #define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */ 2218 #define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */ 2219 #define SQLITE_CONFIG_SCRATCH 6 /* No longer used */ 2220 #define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */ 2221 #define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */ 2222 #define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */ 2223 #define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */ 2224 #define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */ 2225 /* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */ 2226 #define SQLITE_CONFIG_LOOKASIDE 13 /* int int */ 2227 #define SQLITE_CONFIG_PCACHE 14 /* no-op */ 2228 #define SQLITE_CONFIG_GETPCACHE 15 /* no-op */ 2229 #define SQLITE_CONFIG_LOG 16 /* xFunc, void* */ 2230 #define SQLITE_CONFIG_URI 17 /* int */ 2231 #define SQLITE_CONFIG_PCACHE2 18 /* sqlite3_pcache_methods2* */ 2232 #define SQLITE_CONFIG_GETPCACHE2 19 /* sqlite3_pcache_methods2* */ 2233 #define SQLITE_CONFIG_COVERING_INDEX_SCAN 20 /* int */ 2234 #define SQLITE_CONFIG_SQLLOG 21 /* xSqllog, void* */ 2235 #define SQLITE_CONFIG_MMAP_SIZE 22 /* sqlite3_int64, sqlite3_int64 */ 2236 #define SQLITE_CONFIG_WIN32_HEAPSIZE 23 /* int nByte */ 2237 #define SQLITE_CONFIG_PCACHE_HDRSZ 24 /* int *psz */ 2238 #define SQLITE_CONFIG_PMASZ 25 /* unsigned int szPma */ 2239 #define SQLITE_CONFIG_STMTJRNL_SPILL 26 /* int nByte */ 2240 #define SQLITE_CONFIG_SMALL_MALLOC 27 /* boolean */ 2241 #define SQLITE_CONFIG_SORTERREF_SIZE 28 /* int nByte */ 2242 #define SQLITE_CONFIG_MEMDB_MAXSIZE 29 /* sqlite3_int64 */ 2243 #define SQLITE_CONFIG_ROWID_IN_VIEW 30 /* int* */ 2244 2245 /* 2246 ** CAPI3REF: Database Connection Configuration Options 2247 ** 2248 ** These constants are the available integer configuration options that 2249 ** can be passed as the second parameter to the [sqlite3_db_config()] interface. 2250 ** 2251 ** The [sqlite3_db_config()] interface is a var-args function. It takes a 2252 ** variable number of parameters, though always at least two. The number of 2253 ** parameters passed into sqlite3_db_config() depends on which of these 2254 ** constants is given as the second parameter. This documentation page 2255 ** refers to parameters beyond the second as "arguments". Thus, when this 2256 ** page says "the N-th argument" it means "the N-th parameter past the 2257 ** configuration option" or "the (N+2)-th parameter to sqlite3_db_config()". 2258 ** 2259 ** New configuration options may be added in future releases of SQLite. 2260 ** Existing configuration options might be discontinued. Applications 2261 ** should check the return code from [sqlite3_db_config()] to make sure that 2262 ** the call worked. ^The [sqlite3_db_config()] interface will return a 2263 ** non-zero [error code] if a discontinued or unsupported configuration option 2264 ** is invoked. 2265 ** 2266 ** <dl> 2267 ** [[SQLITE_DBCONFIG_LOOKASIDE]] 2268 ** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt> 2269 ** <dd> The SQLITE_DBCONFIG_LOOKASIDE option is used to adjust the 2270 ** configuration of the [lookaside memory allocator] within a database 2271 ** connection. 2272 ** The arguments to the SQLITE_DBCONFIG_LOOKASIDE option are <i>not</i> 2273 ** in the [DBCONFIG arguments|usual format]. 2274 ** The SQLITE_DBCONFIG_LOOKASIDE option takes three arguments, not two, 2275 ** so that a call to [sqlite3_db_config()] that uses SQLITE_DBCONFIG_LOOKASIDE 2276 ** should have a total of five parameters. 2277 ** <ol> 2278 ** <li><p>The first argument ("buf") is a 2279 ** pointer to a memory buffer to use for lookaside memory. 2280 ** The first argument may be NULL in which case SQLite will allocate the 2281 ** lookaside buffer itself using [sqlite3_malloc()]. 2282 ** <li><P>The second argument ("sz") is the 2283 ** size of each lookaside buffer slot. Lookaside is disabled if "sz" 2284 ** is less than 8. The "sz" argument should be a multiple of 8 less than 2285 ** 65536. If "sz" does not meet this constraint, it is reduced in size until 2286 ** it does. 2287 ** <li><p>The third argument ("cnt") is the number of slots. 2288 ** Lookaside is disabled if "cnt"is less than 1. 2289 * The "cnt" value will be reduced, if necessary, so 2290 ** that the product of "sz" and "cnt" does not exceed 2,147,418,112. The "cnt" 2291 ** parameter is usually chosen so that the product of "sz" and "cnt" is less 2292 ** than 1,000,000. 2293 ** </ol> 2294 ** <p>If the "buf" argument is not NULL, then it must 2295 ** point to a memory buffer with a size that is greater than 2296 ** or equal to the product of "sz" and "cnt". 2297 ** The buffer must be aligned to an 8-byte boundary. 2298 ** The lookaside memory 2299 ** configuration for a database connection can only be changed when that 2300 ** connection is not currently using lookaside memory, or in other words 2301 ** when the value returned by [SQLITE_DBSTATUS_LOOKASIDE_USED] is zero. 2302 ** Any attempt to change the lookaside memory configuration when lookaside 2303 ** memory is in use leaves the configuration unchanged and returns 2304 ** [SQLITE_BUSY]. 2305 ** If the "buf" argument is NULL and an attempt 2306 ** to allocate memory based on "sz" and "cnt" fails, then 2307 ** lookaside is silently disabled. 2308 ** <p> 2309 ** The [SQLITE_CONFIG_LOOKASIDE] configuration option can be used to set the 2310 ** default lookaside configuration at initialization. The 2311 ** [-DSQLITE_DEFAULT_LOOKASIDE] option can be used to set the default lookaside 2312 ** configuration at compile-time. Typical values for lookaside are 1200 for 2313 ** "sz" and 40 to 100 for "cnt". 2314 ** </dd> 2315 ** 2316 ** [[SQLITE_DBCONFIG_ENABLE_FKEY]] 2317 ** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt> 2318 ** <dd> ^This option is used to enable or disable the enforcement of 2319 ** [foreign key constraints]. This is the same setting that is 2320 ** enabled or disabled by the [PRAGMA foreign_keys] statement. 2321 ** The first argument is an integer which is 0 to disable FK enforcement, 2322 ** positive to enable FK enforcement or negative to leave FK enforcement 2323 ** unchanged. The second parameter is a pointer to an integer into which 2324 ** is written 0 or 1 to indicate whether FK enforcement is off or on 2325 ** following this call. The second parameter may be a NULL pointer, in 2326 ** which case the FK enforcement setting is not reported back. </dd> 2327 ** 2328 ** [[SQLITE_DBCONFIG_ENABLE_TRIGGER]] 2329 ** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt> 2330 ** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers]. 2331 ** There should be two additional arguments. 2332 ** The first argument is an integer which is 0 to disable triggers, 2333 ** positive to enable triggers or negative to leave the setting unchanged. 2334 ** The second parameter is a pointer to an integer into which 2335 ** is written 0 or 1 to indicate whether triggers are disabled or enabled 2336 ** following this call. The second parameter may be a NULL pointer, in 2337 ** which case the trigger setting is not reported back. 2338 ** 2339 ** <p>Originally this option disabled all triggers. ^(However, since 2340 ** SQLite version 3.35.0, TEMP triggers are still allowed even if 2341 ** this option is off. So, in other words, this option now only disables 2342 ** triggers in the main database schema or in the schemas of [ATTACH]-ed 2343 ** databases.)^ </dd> 2344 ** 2345 ** [[SQLITE_DBCONFIG_ENABLE_VIEW]] 2346 ** <dt>SQLITE_DBCONFIG_ENABLE_VIEW</dt> 2347 ** <dd> ^This option is used to enable or disable [CREATE VIEW | views]. 2348 ** There must be two additional arguments. 2349 ** The first argument is an integer which is 0 to disable views, 2350 ** positive to enable views or negative to leave the setting unchanged. 2351 ** The second parameter is a pointer to an integer into which 2352 ** is written 0 or 1 to indicate whether views are disabled or enabled 2353 ** following this call. The second parameter may be a NULL pointer, in 2354 ** which case the view setting is not reported back. 2355 ** 2356 ** <p>Originally this option disabled all views. ^(However, since 2357 ** SQLite version 3.35.0, TEMP views are still allowed even if 2358 ** this option is off. So, in other words, this option now only disables 2359 ** views in the main database schema or in the schemas of ATTACH-ed 2360 ** databases.)^ </dd> 2361 ** 2362 ** [[SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER]] 2363 ** <dt>SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER</dt> 2364 ** <dd> ^This option is used to enable or disable using the 2365 ** [fts3_tokenizer()] function - part of the [FTS3] full-text search engine 2366 ** extension - without using bound parameters as the parameters. Doing so 2367 ** is disabled by default. There must be two additional arguments. The first 2368 ** argument is an integer. If it is passed 0, then using fts3_tokenizer() 2369 ** without bound parameters is disabled. If it is passed a positive value, 2370 ** then calling fts3_tokenizer without bound parameters is enabled. If it 2371 ** is passed a negative value, this setting is not modified - this can be 2372 ** used to query for the current setting. The second parameter is a pointer 2373 ** to an integer into which is written 0 or 1 to indicate the current value 2374 ** of this setting (after it is modified, if applicable). The second 2375 ** parameter may be a NULL pointer, in which case the value of the setting 2376 ** is not reported back. Refer to [FTS3] documentation for further details. 2377 ** </dd> 2378 ** 2379 ** [[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION]] 2380 ** <dt>SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION</dt> 2381 ** <dd> ^This option is used to enable or disable the [sqlite3_load_extension()] 2382 ** interface independently of the [load_extension()] SQL function. 2383 ** The [sqlite3_enable_load_extension()] API enables or disables both the 2384 ** C-API [sqlite3_load_extension()] and the SQL function [load_extension()]. 2385 ** There must be two additional arguments. 2386 ** When the first argument to this interface is 1, then only the C-API is 2387 ** enabled and the SQL function remains disabled. If the first argument to 2388 ** this interface is 0, then both the C-API and the SQL function are disabled. 2389 ** If the first argument is -1, then no changes are made to the state of either 2390 ** the C-API or the SQL function. 2391 ** The second parameter is a pointer to an integer into which 2392 ** is written 0 or 1 to indicate whether [sqlite3_load_extension()] interface 2393 ** is disabled or enabled following this call. The second parameter may 2394 ** be a NULL pointer, in which case the new setting is not reported back. 2395 ** </dd> 2396 ** 2397 ** [[SQLITE_DBCONFIG_MAINDBNAME]] <dt>SQLITE_DBCONFIG_MAINDBNAME</dt> 2398 ** <dd> ^This option is used to change the name of the "main" database 2399 ** schema. This option does not follow the 2400 ** [DBCONFIG arguments|usual SQLITE_DBCONFIG argument format]. 2401 ** This option takes exactly one additional argument so that the 2402 ** [sqlite3_db_config()] call has a total of three parameters. The 2403 ** extra argument must be a pointer to a constant UTF8 string which 2404 ** will become the new schema name in place of "main". ^SQLite does 2405 ** not make a copy of the new main schema name string, so the application 2406 ** must ensure that the argument passed into SQLITE_DBCONFIG MAINDBNAME 2407 ** is unchanged until after the database connection closes. 2408 ** </dd> 2409 ** 2410 ** [[SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE]] 2411 ** <dt>SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE</dt> 2412 ** <dd> Usually, when a database in [WAL mode] is closed or detached from a 2413 ** database handle, SQLite checks if if there are other connections to the 2414 ** same database, and if there are no other database connection (if the 2415 ** connection being closed is the last open connection to the database), 2416 ** then SQLite performs a [checkpoint] before closing the connection and 2417 ** deletes the WAL file. The SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE option can 2418 ** be used to override that behavior. The first argument passed to this 2419 ** operation (the third parameter to [sqlite3_db_config()]) is an integer 2420 ** which is positive to disable checkpoints-on-close, or zero (the default) 2421 ** to enable them, and negative to leave the setting unchanged. 2422 ** The second argument (the fourth parameter) is a pointer to an integer 2423 ** into which is written 0 or 1 to indicate whether checkpoints-on-close 2424 ** have been disabled - 0 if they are not disabled, 1 if they are. 2425 ** </dd> 2426 ** 2427 ** [[SQLITE_DBCONFIG_ENABLE_QPSG]] <dt>SQLITE_DBCONFIG_ENABLE_QPSG</dt> 2428 ** <dd>^(The SQLITE_DBCONFIG_ENABLE_QPSG option activates or deactivates 2429 ** the [query planner stability guarantee] (QPSG). When the QPSG is active, 2430 ** a single SQL query statement will always use the same algorithm regardless 2431 ** of values of [bound parameters].)^ The QPSG disables some query optimizations 2432 ** that look at the values of bound parameters, which can make some queries 2433 ** slower. But the QPSG has the advantage of more predictable behavior. With 2434 ** the QPSG active, SQLite will always use the same query plan in the field as 2435 ** was used during testing in the lab. 2436 ** The first argument to this setting is an integer which is 0 to disable 2437 ** the QPSG, positive to enable QPSG, or negative to leave the setting 2438 ** unchanged. The second parameter is a pointer to an integer into which 2439 ** is written 0 or 1 to indicate whether the QPSG is disabled or enabled 2440 ** following this call. 2441 ** </dd> 2442 ** 2443 ** [[SQLITE_DBCONFIG_TRIGGER_EQP]] <dt>SQLITE_DBCONFIG_TRIGGER_EQP</dt> 2444 ** <dd> By default, the output of EXPLAIN QUERY PLAN commands does not 2445 ** include output for any operations performed by trigger programs. This 2446 ** option is used to set or clear (the default) a flag that governs this 2447 ** behavior. The first parameter passed to this operation is an integer - 2448 ** positive to enable output for trigger programs, or zero to disable it, 2449 ** or negative to leave the setting unchanged. 2450 ** The second parameter is a pointer to an integer into which is written 2451 ** 0 or 1 to indicate whether output-for-triggers has been disabled - 0 if 2452 ** it is not disabled, 1 if it is. 2453 ** </dd> 2454 ** 2455 ** [[SQLITE_DBCONFIG_RESET_DATABASE]] <dt>SQLITE_DBCONFIG_RESET_DATABASE</dt> 2456 ** <dd> Set the SQLITE_DBCONFIG_RESET_DATABASE flag and then run 2457 ** [VACUUM] in order to reset a database back to an empty database 2458 ** with no schema and no content. The following process works even for 2459 ** a badly corrupted database file: 2460 ** <ol> 2461 ** <li> If the database connection is newly opened, make sure it has read the 2462 ** database schema by preparing then discarding some query against the 2463 ** database, or calling sqlite3_table_column_metadata(), ignoring any 2464 ** errors. This step is only necessary if the application desires to keep 2465 ** the database in WAL mode after the reset if it was in WAL mode before 2466 ** the reset. 2467 ** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 1, 0); 2468 ** <li> [sqlite3_exec](db, "[VACUUM]", 0, 0, 0); 2469 ** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 0, 0); 2470 ** </ol> 2471 ** Because resetting a database is destructive and irreversible, the 2472 ** process requires the use of this obscure API and multiple steps to 2473 ** help ensure that it does not happen by accident. Because this 2474 ** feature must be capable of resetting corrupt databases, and 2475 ** shutting down virtual tables may require access to that corrupt 2476 ** storage, the library must abandon any installed virtual tables 2477 ** without calling their xDestroy() methods. 2478 ** 2479 ** [[SQLITE_DBCONFIG_DEFENSIVE]] <dt>SQLITE_DBCONFIG_DEFENSIVE</dt> 2480 ** <dd>The SQLITE_DBCONFIG_DEFENSIVE option activates or deactivates the 2481 ** "defensive" flag for a database connection. When the defensive 2482 ** flag is enabled, language features that allow ordinary SQL to 2483 ** deliberately corrupt the database file are disabled. The disabled 2484 ** features include but are not limited to the following: 2485 ** <ul> 2486 ** <li> The [PRAGMA writable_schema=ON] statement. 2487 ** <li> The [PRAGMA journal_mode=OFF] statement. 2488 ** <li> The [PRAGMA schema_version=N] statement. 2489 ** <li> Writes to the [sqlite_dbpage] virtual table. 2490 ** <li> Direct writes to [shadow tables]. 2491 ** </ul> 2492 ** </dd> 2493 ** 2494 ** [[SQLITE_DBCONFIG_WRITABLE_SCHEMA]] <dt>SQLITE_DBCONFIG_WRITABLE_SCHEMA</dt> 2495 ** <dd>The SQLITE_DBCONFIG_WRITABLE_SCHEMA option activates or deactivates the 2496 ** "writable_schema" flag. This has the same effect and is logically equivalent 2497 ** to setting [PRAGMA writable_schema=ON] or [PRAGMA writable_schema=OFF]. 2498 ** The first argument to this setting is an integer which is 0 to disable 2499 ** the writable_schema, positive to enable writable_schema, or negative to 2500 ** leave the setting unchanged. The second parameter is a pointer to an 2501 ** integer into which is written 0 or 1 to indicate whether the writable_schema 2502 ** is enabled or disabled following this call. 2503 ** </dd> 2504 ** 2505 ** [[SQLITE_DBCONFIG_LEGACY_ALTER_TABLE]] 2506 ** <dt>SQLITE_DBCONFIG_LEGACY_ALTER_TABLE</dt> 2507 ** <dd>The SQLITE_DBCONFIG_LEGACY_ALTER_TABLE option activates or deactivates 2508 ** the legacy behavior of the [ALTER TABLE RENAME] command such that it 2509 ** behaves as it did prior to [version 3.24.0] (2018-06-04). See the 2510 ** "Compatibility Notice" on the [ALTER TABLE RENAME documentation] for 2511 ** additional information. This feature can also be turned on and off 2512 ** using the [PRAGMA legacy_alter_table] statement. 2513 ** </dd> 2514 ** 2515 ** [[SQLITE_DBCONFIG_DQS_DML]] 2516 ** <dt>SQLITE_DBCONFIG_DQS_DML</dt> 2517 ** <dd>The SQLITE_DBCONFIG_DQS_DML option activates or deactivates 2518 ** the legacy [double-quoted string literal] misfeature for DML statements 2519 ** only, that is DELETE, INSERT, SELECT, and UPDATE statements. The 2520 ** default value of this setting is determined by the [-DSQLITE_DQS] 2521 ** compile-time option. 2522 ** </dd> 2523 ** 2524 ** [[SQLITE_DBCONFIG_DQS_DDL]] 2525 ** <dt>SQLITE_DBCONFIG_DQS_DDL</dt> 2526 ** <dd>The SQLITE_DBCONFIG_DQS option activates or deactivates 2527 ** the legacy [double-quoted string literal] misfeature for DDL statements, 2528 ** such as CREATE TABLE and CREATE INDEX. The 2529 ** default value of this setting is determined by the [-DSQLITE_DQS] 2530 ** compile-time option. 2531 ** </dd> 2532 ** 2533 ** [[SQLITE_DBCONFIG_TRUSTED_SCHEMA]] 2534 ** <dt>SQLITE_DBCONFIG_TRUSTED_SCHEMA</dt> 2535 ** <dd>The SQLITE_DBCONFIG_TRUSTED_SCHEMA option tells SQLite to 2536 ** assume that database schemas are untainted by malicious content. 2537 ** When the SQLITE_DBCONFIG_TRUSTED_SCHEMA option is disabled, SQLite 2538 ** takes additional defensive steps to protect the application from harm 2539 ** including: 2540 ** <ul> 2541 ** <li> Prohibit the use of SQL functions inside triggers, views, 2542 ** CHECK constraints, DEFAULT clauses, expression indexes, 2543 ** partial indexes, or generated columns 2544 ** unless those functions are tagged with [SQLITE_INNOCUOUS]. 2545 ** <li> Prohibit the use of virtual tables inside of triggers or views 2546 ** unless those virtual tables are tagged with [SQLITE_VTAB_INNOCUOUS]. 2547 ** </ul> 2548 ** This setting defaults to "on" for legacy compatibility, however 2549 ** all applications are advised to turn it off if possible. This setting 2550 ** can also be controlled using the [PRAGMA trusted_schema] statement. 2551 ** </dd> 2552 ** 2553 ** [[SQLITE_DBCONFIG_LEGACY_FILE_FORMAT]] 2554 ** <dt>SQLITE_DBCONFIG_LEGACY_FILE_FORMAT</dt> 2555 ** <dd>The SQLITE_DBCONFIG_LEGACY_FILE_FORMAT option activates or deactivates 2556 ** the legacy file format flag. When activated, this flag causes all newly 2557 ** created database files to have a schema format version number (the 4-byte 2558 ** integer found at offset 44 into the database header) of 1. This in turn 2559 ** means that the resulting database file will be readable and writable by 2560 ** any SQLite version back to 3.0.0 ([dateof:3.0.0]). Without this setting, 2561 ** newly created databases are generally not understandable by SQLite versions 2562 ** prior to 3.3.0 ([dateof:3.3.0]). As these words are written, there 2563 ** is now scarcely any need to generate database files that are compatible 2564 ** all the way back to version 3.0.0, and so this setting is of little 2565 ** practical use, but is provided so that SQLite can continue to claim the 2566 ** ability to generate new database files that are compatible with version 2567 ** 3.0.0. 2568 ** <p>Note that when the SQLITE_DBCONFIG_LEGACY_FILE_FORMAT setting is on, 2569 ** the [VACUUM] command will fail with an obscure error when attempting to 2570 ** process a table with generated columns and a descending index. This is 2571 ** not considered a bug since SQLite versions 3.3.0 and earlier do not support 2572 ** either generated columns or descending indexes. 2573 ** </dd> 2574 ** 2575 ** [[SQLITE_DBCONFIG_STMT_SCANSTATUS]] 2576 ** <dt>SQLITE_DBCONFIG_STMT_SCANSTATUS</dt> 2577 ** <dd>The SQLITE_DBCONFIG_STMT_SCANSTATUS option is only useful in 2578 ** [SQLITE_ENABLE_STMT_SCANSTATUS] builds. In this case, it sets or clears 2579 ** a flag that enables collection of run-time performance statistics 2580 ** used by [sqlite3_stmt_scanstatus_v2()] and the [nexec and ncycle] 2581 ** columns of the [bytecode virtual table]. 2582 ** For statistics to be collected, the flag must be set on 2583 ** the database handle both when the SQL statement is 2584 ** [sqlite3_prepare|prepared] and when it is [sqlite3_step|stepped]. 2585 ** The flag is set (collection of statistics is enabled) by default. 2586 ** <p>This option takes two arguments: an integer and a pointer to 2587 ** an integer. The first argument is 1, 0, or -1 to enable, disable, or 2588 ** leave unchanged the statement scanstatus option. If the second argument 2589 ** is not NULL, then the value of the statement scanstatus setting after 2590 ** processing the first argument is written into the integer that the second 2591 ** argument points to. 2592 ** </dd> 2593 ** 2594 ** [[SQLITE_DBCONFIG_REVERSE_SCANORDER]] 2595 ** <dt>SQLITE_DBCONFIG_REVERSE_SCANORDER</dt> 2596 ** <dd>The SQLITE_DBCONFIG_REVERSE_SCANORDER option changes the default order 2597 ** in which tables and indexes are scanned so that the scans start at the end 2598 ** and work toward the beginning rather than starting at the beginning and 2599 ** working toward the end. Setting SQLITE_DBCONFIG_REVERSE_SCANORDER is the 2600 ** same as setting [PRAGMA reverse_unordered_selects]. <p>This option takes 2601 ** two arguments which are an integer and a pointer to an integer. The first 2602 ** argument is 1, 0, or -1 to enable, disable, or leave unchanged the 2603 ** reverse scan order flag, respectively. If the second argument is not NULL, 2604 ** then 0 or 1 is written into the integer that the second argument points to 2605 ** depending on if the reverse scan order flag is set after processing the 2606 ** first argument. 2607 ** </dd> 2608 ** 2609 ** [[SQLITE_DBCONFIG_ENABLE_ATTACH_CREATE]] 2610 ** <dt>SQLITE_DBCONFIG_ENABLE_ATTACH_CREATE</dt> 2611 ** <dd>The SQLITE_DBCONFIG_ENABLE_ATTACH_CREATE option enables or disables 2612 ** the ability of the [ATTACH DATABASE] SQL command to create a new database 2613 ** file if the database filed named in the ATTACH command does not already 2614 ** exist. This ability of ATTACH to create a new database is enabled by 2615 ** default. Applications can disable or reenable the ability for ATTACH to 2616 ** create new database files using this DBCONFIG option.<p> 2617 ** This option takes two arguments which are an integer and a pointer 2618 ** to an integer. The first argument is 1, 0, or -1 to enable, disable, or 2619 ** leave unchanged the attach-create flag, respectively. If the second 2620 ** argument is not NULL, then 0 or 1 is written into the integer that the 2621 ** second argument points to depending on if the attach-create flag is set 2622 ** after processing the first argument. 2623 ** </dd> 2624 ** 2625 ** [[SQLITE_DBCONFIG_ENABLE_ATTACH_WRITE]] 2626 ** <dt>SQLITE_DBCONFIG_ENABLE_ATTACH_WRITE</dt> 2627 ** <dd>The SQLITE_DBCONFIG_ENABLE_ATTACH_WRITE option enables or disables the 2628 ** ability of the [ATTACH DATABASE] SQL command to open a database for writing. 2629 ** This capability is enabled by default. Applications can disable or 2630 ** reenable this capability using the current DBCONFIG option. If 2631 ** this capability is disabled, the [ATTACH] command will still work, 2632 ** but the database will be opened read-only. If this option is disabled, 2633 ** then the ability to create a new database using [ATTACH] is also disabled, 2634 ** regardless of the value of the [SQLITE_DBCONFIG_ENABLE_ATTACH_CREATE] 2635 ** option.<p> 2636 ** This option takes two arguments which are an integer and a pointer 2637 ** to an integer. The first argument is 1, 0, or -1 to enable, disable, or 2638 ** leave unchanged the ability to ATTACH another database for writing, 2639 ** respectively. If the second argument is not NULL, then 0 or 1 is written 2640 ** into the integer to which the second argument points, depending on whether 2641 ** the ability to ATTACH a read/write database is enabled or disabled 2642 ** after processing the first argument. 2643 ** </dd> 2644 ** 2645 ** [[SQLITE_DBCONFIG_ENABLE_COMMENTS]] 2646 ** <dt>SQLITE_DBCONFIG_ENABLE_COMMENTS</dt> 2647 ** <dd>The SQLITE_DBCONFIG_ENABLE_COMMENTS option enables or disables the 2648 ** ability to include comments in SQL text. Comments are enabled by default. 2649 ** An application can disable or reenable comments in SQL text using this 2650 ** DBCONFIG option.<p> 2651 ** This option takes two arguments which are an integer and a pointer 2652 ** to an integer. The first argument is 1, 0, or -1 to enable, disable, or 2653 ** leave unchanged the ability to use comments in SQL text, 2654 ** respectively. If the second argument is not NULL, then 0 or 1 is written 2655 ** into the integer that the second argument points to depending on if 2656 ** comments are allowed in SQL text after processing the first argument. 2657 ** </dd> 2658 ** 2659 ** [[SQLITE_DBCONFIG_FP_DIGITS]] 2660 ** <dt>SQLITE_DBCONFIG_FP_DIGITS</dt> 2661 ** <dd>The SQLITE_DBCONFIG_FP_DIGITS setting is a small integer that determines 2662 ** the number of significant digits that SQLite will attempt to preserve when 2663 ** converting floating point numbers (IEEE 754 "doubles") into text. The 2664 ** default value 17, as of SQLite version 3.52.0. The value was 15 in all 2665 ** prior versions.<p> 2666 ** This option takes two arguments which are an integer and a pointer 2667 ** to an integer. The first argument is a small integer, between 3 and 23, or 2668 ** zero. The FP_DIGITS setting is changed to that small integer, or left 2669 ** unaltered if the first argument is zero or out of range. The second argument 2670 ** is a pointer to an integer. If the pointer is not NULL, then the value of 2671 ** the FP_DIGITS setting, after possibly being modified by the first 2672 ** arguments, is written into the integer to which the second argument points. 2673 ** </dd> 2674 ** 2675 ** </dl> 2676 ** 2677 ** [[DBCONFIG arguments]] <h3>Arguments To SQLITE_DBCONFIG Options</h3> 2678 ** 2679 ** <p>Most of the SQLITE_DBCONFIG options take two arguments, so that the 2680 ** overall call to [sqlite3_db_config()] has a total of four parameters. 2681 ** The first argument (the third parameter to sqlite3_db_config()) is 2682 ** an integer. 2683 ** The second argument is a pointer to an integer. If the first argument is 1, 2684 ** then the option becomes enabled. If the first integer argument is 0, 2685 ** then the option is disabled. 2686 ** If the first argument is -1, then the option setting 2687 ** is unchanged. The second argument, the pointer to an integer, may be NULL. 2688 ** If the second argument is not NULL, then a value of 0 or 1 is written into 2689 ** the integer to which the second argument points, depending on whether the 2690 ** setting is disabled or enabled after applying any changes specified by 2691 ** the first argument. 2692 ** 2693 ** <p>While most SQLITE_DBCONFIG options use the argument format 2694 ** described in the previous paragraph, the [SQLITE_DBCONFIG_MAINDBNAME], 2695 ** [SQLITE_DBCONFIG_LOOKASIDE], and [SQLITE_DBCONFIG_FP_DIGITS] options 2696 ** are different. See the documentation of those exceptional options for 2697 ** details. 2698 */ 2699 #define SQLITE_DBCONFIG_MAINDBNAME 1000 /* const char* */ 2700 #define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */ 2701 #define SQLITE_DBCONFIG_ENABLE_FKEY 1002 /* int int* */ 2702 #define SQLITE_DBCONFIG_ENABLE_TRIGGER 1003 /* int int* */ 2703 #define SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER 1004 /* int int* */ 2704 #define SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION 1005 /* int int* */ 2705 #define SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE 1006 /* int int* */ 2706 #define SQLITE_DBCONFIG_ENABLE_QPSG 1007 /* int int* */ 2707 #define SQLITE_DBCONFIG_TRIGGER_EQP 1008 /* int int* */ 2708 #define SQLITE_DBCONFIG_RESET_DATABASE 1009 /* int int* */ 2709 #define SQLITE_DBCONFIG_DEFENSIVE 1010 /* int int* */ 2710 #define SQLITE_DBCONFIG_WRITABLE_SCHEMA 1011 /* int int* */ 2711 #define SQLITE_DBCONFIG_LEGACY_ALTER_TABLE 1012 /* int int* */ 2712 #define SQLITE_DBCONFIG_DQS_DML 1013 /* int int* */ 2713 #define SQLITE_DBCONFIG_DQS_DDL 1014 /* int int* */ 2714 #define SQLITE_DBCONFIG_ENABLE_VIEW 1015 /* int int* */ 2715 #define SQLITE_DBCONFIG_LEGACY_FILE_FORMAT 1016 /* int int* */ 2716 #define SQLITE_DBCONFIG_TRUSTED_SCHEMA 1017 /* int int* */ 2717 #define SQLITE_DBCONFIG_STMT_SCANSTATUS 1018 /* int int* */ 2718 #define SQLITE_DBCONFIG_REVERSE_SCANORDER 1019 /* int int* */ 2719 #define SQLITE_DBCONFIG_ENABLE_ATTACH_CREATE 1020 /* int int* */ 2720 #define SQLITE_DBCONFIG_ENABLE_ATTACH_WRITE 1021 /* int int* */ 2721 #define SQLITE_DBCONFIG_ENABLE_COMMENTS 1022 /* int int* */ 2722 #define SQLITE_DBCONFIG_FP_DIGITS 1023 /* int int* */ 2723 #define SQLITE_DBCONFIG_MAX 1023 /* Largest DBCONFIG */ 2724 2725 /* 2726 ** CAPI3REF: Enable Or Disable Extended Result Codes 2727 ** METHOD: sqlite3 2728 ** 2729 ** ^The sqlite3_extended_result_codes() routine enables or disables the 2730 ** [extended result codes] feature of SQLite. ^The extended result 2731 ** codes are disabled by default for historical compatibility. 2732 */ 2733 SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff); 2734 2735 /* 2736 ** CAPI3REF: Last Insert Rowid 2737 ** METHOD: sqlite3 2738 ** 2739 ** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables) 2740 ** has a unique 64-bit signed 2741 ** integer key called the [ROWID | "rowid"]. ^The rowid is always available 2742 ** as an undeclared column named ROWID, OID, or _ROWID_ as long as those 2743 ** names are not also used by explicitly declared columns. ^If 2744 ** the table has a column of type [INTEGER PRIMARY KEY] then that column 2745 ** is another alias for the rowid. 2746 ** 2747 ** ^The sqlite3_last_insert_rowid(D) interface usually returns the [rowid] of 2748 ** the most recent successful [INSERT] into a rowid table or [virtual table] 2749 ** on database connection D. ^Inserts into [WITHOUT ROWID] tables are not 2750 ** recorded. ^If no successful [INSERT]s into rowid tables have ever occurred 2751 ** on the database connection D, then sqlite3_last_insert_rowid(D) returns 2752 ** zero. 2753 ** 2754 ** As well as being set automatically as rows are inserted into database 2755 ** tables, the value returned by this function may be set explicitly by 2756 ** [sqlite3_set_last_insert_rowid()] 2757 ** 2758 ** Some virtual table implementations may INSERT rows into rowid tables as 2759 ** part of committing a transaction (e.g. to flush data accumulated in memory 2760 ** to disk). In this case subsequent calls to this function return the rowid 2761 ** associated with these internal INSERT operations, which leads to 2762 ** unintuitive results. Virtual table implementations that do write to rowid 2763 ** tables in this way can avoid this problem by restoring the original 2764 ** rowid value using [sqlite3_set_last_insert_rowid()] before returning 2765 ** control to the user. 2766 ** 2767 ** ^(If an [INSERT] occurs within a trigger then this routine will 2768 ** return the [rowid] of the inserted row as long as the trigger is 2769 ** running. Once the trigger program ends, the value returned 2770 ** by this routine reverts to what it was before the trigger was fired.)^ 2771 ** 2772 ** ^An [INSERT] that fails due to a constraint violation is not a 2773 ** successful [INSERT] and does not change the value returned by this 2774 ** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK, 2775 ** and INSERT OR ABORT make no changes to the return value of this 2776 ** routine when their insertion fails. ^(When INSERT OR REPLACE 2777 ** encounters a constraint violation, it does not fail. The 2778 ** INSERT continues to completion after deleting rows that caused 2779 ** the constraint problem so INSERT OR REPLACE will always change 2780 ** the return value of this interface.)^ 2781 ** 2782 ** ^For the purposes of this routine, an [INSERT] is considered to 2783 ** be successful even if it is subsequently rolled back. 2784 ** 2785 ** This function is accessible to SQL statements via the 2786 ** [last_insert_rowid() SQL function]. 2787 ** 2788 ** If a separate thread performs a new [INSERT] on the same 2789 ** database connection while the [sqlite3_last_insert_rowid()] 2790 ** function is running and thus changes the last insert [rowid], 2791 ** then the value returned by [sqlite3_last_insert_rowid()] is 2792 ** unpredictable and might not equal either the old or the new 2793 ** last insert [rowid]. 2794 */ 2795 SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*); 2796 2797 /* 2798 ** CAPI3REF: Set the Last Insert Rowid value. 2799 ** METHOD: sqlite3 2800 ** 2801 ** The sqlite3_set_last_insert_rowid(D, R) method allows the application to 2802 ** set the value returned by calling sqlite3_last_insert_rowid(D) to R 2803 ** without inserting a row into the database. 2804 */ 2805 SQLITE_API void sqlite3_set_last_insert_rowid(sqlite3*,sqlite3_int64); 2806 2807 /* 2808 ** CAPI3REF: Count The Number Of Rows Modified 2809 ** METHOD: sqlite3 2810 ** 2811 ** ^These functions return the number of rows modified, inserted or 2812 ** deleted by the most recently completed INSERT, UPDATE or DELETE 2813 ** statement on the database connection specified by the only parameter. 2814 ** The two functions are identical except for the type of the return value 2815 ** and that if the number of rows modified by the most recent INSERT, UPDATE, 2816 ** or DELETE is greater than the maximum value supported by type "int", then 2817 ** the return value of sqlite3_changes() is undefined. ^Executing any other 2818 ** type of SQL statement does not modify the value returned by these functions. 2819 ** For the purposes of this interface, a CREATE TABLE AS SELECT statement 2820 ** does not count as an INSERT, UPDATE or DELETE statement and hence the rows 2821 ** added to the new table by the CREATE TABLE AS SELECT statement are not 2822 ** counted. 2823 ** 2824 ** ^Only changes made directly by the INSERT, UPDATE or DELETE statement are 2825 ** considered - auxiliary changes caused by [CREATE TRIGGER | triggers], 2826 ** [foreign key actions] or [REPLACE] constraint resolution are not counted. 2827 ** 2828 ** Changes to a view that are intercepted by 2829 ** [INSTEAD OF trigger | INSTEAD OF triggers] are not counted. ^The value 2830 ** returned by sqlite3_changes() immediately after an INSERT, UPDATE or 2831 ** DELETE statement run on a view is always zero. Only changes made to real 2832 ** tables are counted. 2833 ** 2834 ** Things are more complicated if the sqlite3_changes() function is 2835 ** executed while a trigger program is running. This may happen if the 2836 ** program uses the [changes() SQL function], or if some other callback 2837 ** function invokes sqlite3_changes() directly. Essentially: 2838 ** 2839 ** <ul> 2840 ** <li> ^(Before entering a trigger program the value returned by 2841 ** sqlite3_changes() function is saved. After the trigger program 2842 ** has finished, the original value is restored.)^ 2843 ** 2844 ** <li> ^(Within a trigger program each INSERT, UPDATE and DELETE 2845 ** statement sets the value returned by sqlite3_changes() 2846 ** upon completion as normal. Of course, this value will not include 2847 ** any changes performed by sub-triggers, as the sqlite3_changes() 2848 ** value will be saved and restored after each sub-trigger has run.)^ 2849 ** </ul> 2850 ** 2851 ** ^This means that if the changes() SQL function (or similar) is used 2852 ** by the first INSERT, UPDATE or DELETE statement within a trigger, it 2853 ** returns the value as set when the calling statement began executing. 2854 ** ^If it is used by the second or subsequent such statement within a trigger 2855 ** program, the value returned reflects the number of rows modified by the 2856 ** previous INSERT, UPDATE or DELETE statement within the same trigger. 2857 ** 2858 ** If a separate thread makes changes on the same database connection 2859 ** while [sqlite3_changes()] is running then the value returned 2860 ** is unpredictable and not meaningful. 2861 ** 2862 ** See also: 2863 ** <ul> 2864 ** <li> the [sqlite3_total_changes()] interface 2865 ** <li> the [count_changes pragma] 2866 ** <li> the [changes() SQL function] 2867 ** <li> the [data_version pragma] 2868 ** </ul> 2869 */ 2870 SQLITE_API int sqlite3_changes(sqlite3*); 2871 SQLITE_API sqlite3_int64 sqlite3_changes64(sqlite3*); 2872 2873 /* 2874 ** CAPI3REF: Total Number Of Rows Modified 2875 ** METHOD: sqlite3 2876 ** 2877 ** ^These functions return the total number of rows inserted, modified or 2878 ** deleted by all [INSERT], [UPDATE] or [DELETE] statements completed 2879 ** since the database connection was opened, including those executed as 2880 ** part of trigger programs. The two functions are identical except for the 2881 ** type of the return value and that if the number of rows modified by the 2882 ** connection exceeds the maximum value supported by type "int", then 2883 ** the return value of sqlite3_total_changes() is undefined. ^Executing 2884 ** any other type of SQL statement does not affect the value returned by 2885 ** sqlite3_total_changes(). 2886 ** 2887 ** ^Changes made as part of [foreign key actions] are included in the 2888 ** count, but those made as part of REPLACE constraint resolution are 2889 ** not. ^Changes to a view that are intercepted by INSTEAD OF triggers 2890 ** are not counted. 2891 ** 2892 ** The [sqlite3_total_changes(D)] interface only reports the number 2893 ** of rows that changed due to SQL statement run against database 2894 ** connection D. Any changes by other database connections are ignored. 2895 ** To detect changes against a database file from other database 2896 ** connections use the [PRAGMA data_version] command or the 2897 ** [SQLITE_FCNTL_DATA_VERSION] [file control]. 2898 ** 2899 ** If a separate thread makes changes on the same database connection 2900 ** while [sqlite3_total_changes()] is running then the value 2901 ** returned is unpredictable and not meaningful. 2902 ** 2903 ** See also: 2904 ** <ul> 2905 ** <li> the [sqlite3_changes()] interface 2906 ** <li> the [count_changes pragma] 2907 ** <li> the [changes() SQL function] 2908 ** <li> the [data_version pragma] 2909 ** <li> the [SQLITE_FCNTL_DATA_VERSION] [file control] 2910 ** </ul> 2911 */ 2912 SQLITE_API int sqlite3_total_changes(sqlite3*); 2913 SQLITE_API sqlite3_int64 sqlite3_total_changes64(sqlite3*); 2914 2915 /* 2916 ** CAPI3REF: Interrupt A Long-Running Query 2917 ** METHOD: sqlite3 2918 ** 2919 ** ^This function causes any pending database operation to abort and 2920 ** return at its earliest opportunity. This routine is typically 2921 ** called in response to a user action such as pressing "Cancel" 2922 ** or Ctrl-C where the user wants a long query operation to halt 2923 ** immediately. 2924 ** 2925 ** ^It is safe to call this routine from a thread different from the 2926 ** thread that is currently running the database operation. But it 2927 ** is not safe to call this routine with a [database connection] that 2928 ** is closed or might close before sqlite3_interrupt() returns. 2929 ** 2930 ** ^If an SQL operation is very nearly finished at the time when 2931 ** sqlite3_interrupt() is called, then it might not have an opportunity 2932 ** to be interrupted and might continue to completion. 2933 ** 2934 ** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT]. 2935 ** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE 2936 ** that is inside an explicit transaction, then the entire transaction 2937 ** will be rolled back automatically. 2938 ** 2939 ** ^The sqlite3_interrupt(D) call is in effect until all currently running 2940 ** SQL statements on [database connection] D complete. ^Any new SQL statements 2941 ** that are started after the sqlite3_interrupt() call and before the 2942 ** running statement count reaches zero are interrupted as if they had been 2943 ** running prior to the sqlite3_interrupt() call. ^New SQL statements 2944 ** that are started after the running statement count reaches zero are 2945 ** not effected by the sqlite3_interrupt(). 2946 ** ^A call to sqlite3_interrupt(D) that occurs when there are no running 2947 ** SQL statements is a no-op and has no effect on SQL statements 2948 ** that are started after the sqlite3_interrupt() call returns. 2949 ** 2950 ** ^The [sqlite3_is_interrupted(D)] interface can be used to determine whether 2951 ** or not an interrupt is currently in effect for [database connection] D. 2952 ** It returns 1 if an interrupt is currently in effect, or 0 otherwise. 2953 */ 2954 SQLITE_API void sqlite3_interrupt(sqlite3*); 2955 SQLITE_API int sqlite3_is_interrupted(sqlite3*); 2956 2957 /* 2958 ** CAPI3REF: Determine If An SQL Statement Is Complete 2959 ** 2960 ** These routines are useful during command-line input to determine if the 2961 ** currently entered text seems to form a complete SQL statement or 2962 ** if additional input is needed before sending the text into 2963 ** SQLite for parsing. ^These routines return 1 if the input string 2964 ** appears to be a complete SQL statement. ^A statement is judged to be 2965 ** complete if it ends with a semicolon token and is not a prefix of a 2966 ** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within 2967 ** string literals or quoted identifier names or comments are not 2968 ** independent tokens (they are part of the token in which they are 2969 ** embedded) and thus do not count as a statement terminator. ^Whitespace 2970 ** and comments that follow the final semicolon are ignored. 2971 ** 2972 ** ^These routines return 0 if the statement is incomplete. ^If a 2973 ** memory allocation fails, then SQLITE_NOMEM is returned. 2974 ** 2975 ** ^These routines do not parse the SQL statements and thus 2976 ** will not detect syntactically incorrect SQL. 2977 ** 2978 ** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior 2979 ** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked 2980 ** automatically by sqlite3_complete16(). If that initialization fails, 2981 ** then the return value from sqlite3_complete16() will be non-zero 2982 ** regardless of whether or not the input SQL is complete.)^ 2983 ** 2984 ** The input to [sqlite3_complete()] must be a zero-terminated 2985 ** UTF-8 string. 2986 ** 2987 ** The input to [sqlite3_complete16()] must be a zero-terminated 2988 ** UTF-16 string in native byte order. 2989 */ 2990 SQLITE_API int sqlite3_complete(const char *sql); 2991 SQLITE_API int sqlite3_complete16(const void *sql); 2992 2993 /* 2994 ** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors 2995 ** KEYWORDS: {busy-handler callback} {busy handler} 2996 ** METHOD: sqlite3 2997 ** 2998 ** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X 2999 ** that might be invoked with argument P whenever 3000 ** an attempt is made to access a database table associated with 3001 ** [database connection] D when another thread 3002 ** or process has the table locked. 3003 ** The sqlite3_busy_handler() interface is used to implement 3004 ** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout]. 3005 ** 3006 ** ^If the busy callback is NULL, then [SQLITE_BUSY] 3007 ** is returned immediately upon encountering the lock. ^If the busy callback 3008 ** is not NULL, then the callback might be invoked with two arguments. 3009 ** 3010 ** ^The first argument to the busy handler is a copy of the void* pointer which 3011 ** is the third argument to sqlite3_busy_handler(). ^The second argument to 3012 ** the busy handler callback is the number of times that the busy handler has 3013 ** been invoked previously for the same locking event. ^If the 3014 ** busy callback returns 0, then no additional attempts are made to 3015 ** access the database and [SQLITE_BUSY] is returned 3016 ** to the application. 3017 ** ^If the callback returns non-zero, then another attempt 3018 ** is made to access the database and the cycle repeats. 3019 ** 3020 ** The presence of a busy handler does not guarantee that it will be invoked 3021 ** when there is lock contention. ^If SQLite determines that invoking the busy 3022 ** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY] 3023 ** to the application instead of invoking the 3024 ** busy handler. 3025 ** Consider a scenario where one process is holding a read lock that 3026 ** it is trying to promote to a reserved lock and 3027 ** a second process is holding a reserved lock that it is trying 3028 ** to promote to an exclusive lock. The first process cannot proceed 3029 ** because it is blocked by the second and the second process cannot 3030 ** proceed because it is blocked by the first. If both processes 3031 ** invoke the busy handlers, neither will make any progress. Therefore, 3032 ** SQLite returns [SQLITE_BUSY] for the first process, hoping that this 3033 ** will induce the first process to release its read lock and allow 3034 ** the second process to proceed. 3035 ** 3036 ** ^The default busy callback is NULL. 3037 ** 3038 ** ^(There can only be a single busy handler defined for each 3039 ** [database connection]. Setting a new busy handler clears any 3040 ** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()] 3041 ** or evaluating [PRAGMA busy_timeout=N] will change the 3042 ** busy handler and thus clear any previously set busy handler. 3043 ** 3044 ** The busy callback should not take any actions which modify the 3045 ** database connection that invoked the busy handler. In other words, 3046 ** the busy handler is not reentrant. Any such actions 3047 ** result in undefined behavior. 3048 ** 3049 ** A busy handler must not close the database connection 3050 ** or [prepared statement] that invoked the busy handler. 3051 */ 3052 SQLITE_API int sqlite3_busy_handler(sqlite3*,int(*)(void*,int),void*); 3053 3054 /* 3055 ** CAPI3REF: Set A Busy Timeout 3056 ** METHOD: sqlite3 3057 ** 3058 ** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps 3059 ** for a specified amount of time when a table is locked. ^The handler 3060 ** will sleep multiple times until at least "ms" milliseconds of sleeping 3061 ** have accumulated. ^After at least "ms" milliseconds of sleeping, 3062 ** the handler returns 0 which causes [sqlite3_step()] to return 3063 ** [SQLITE_BUSY]. 3064 ** 3065 ** ^Calling this routine with an argument less than or equal to zero 3066 ** turns off all busy handlers. 3067 ** 3068 ** ^(There can only be a single busy handler for a particular 3069 ** [database connection] at any given moment. If another busy handler 3070 ** was defined (using [sqlite3_busy_handler()]) prior to calling 3071 ** this routine, that other busy handler is cleared.)^ 3072 ** 3073 ** See also: [PRAGMA busy_timeout] 3074 */ 3075 SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms); 3076 3077 /* 3078 ** CAPI3REF: Set the Setlk Timeout 3079 ** METHOD: sqlite3 3080 ** 3081 ** This routine is only useful in SQLITE_ENABLE_SETLK_TIMEOUT builds. If 3082 ** the VFS supports blocking locks, it sets the timeout in ms used by 3083 ** eligible locks taken on wal mode databases by the specified database 3084 ** handle. In non-SQLITE_ENABLE_SETLK_TIMEOUT builds, or if the VFS does 3085 ** not support blocking locks, this function is a no-op. 3086 ** 3087 ** Passing 0 to this function disables blocking locks altogether. Passing 3088 ** -1 to this function requests that the VFS blocks for a long time - 3089 ** indefinitely if possible. The results of passing any other negative value 3090 ** are undefined. 3091 ** 3092 ** Internally, each SQLite database handle stores two timeout values - the 3093 ** busy-timeout (used for rollback mode databases, or if the VFS does not 3094 ** support blocking locks) and the setlk-timeout (used for blocking locks 3095 ** on wal-mode databases). The sqlite3_busy_timeout() method sets both 3096 ** values, this function sets only the setlk-timeout value. Therefore, 3097 ** to configure separate busy-timeout and setlk-timeout values for a single 3098 ** database handle, call sqlite3_busy_timeout() followed by this function. 3099 ** 3100 ** Whenever the number of connections to a wal mode database falls from 3101 ** 1 to 0, the last connection takes an exclusive lock on the database, 3102 ** then checkpoints and deletes the wal file. While it is doing this, any 3103 ** new connection that tries to read from the database fails with an 3104 ** SQLITE_BUSY error. Or, if the SQLITE_SETLK_BLOCK_ON_CONNECT flag is 3105 ** passed to this API, the new connection blocks until the exclusive lock 3106 ** has been released. 3107 */ 3108 SQLITE_API int sqlite3_setlk_timeout(sqlite3*, int ms, int flags); 3109 3110 /* 3111 ** CAPI3REF: Flags for sqlite3_setlk_timeout() 3112 */ 3113 #define SQLITE_SETLK_BLOCK_ON_CONNECT 0x01 3114 3115 /* 3116 ** CAPI3REF: Convenience Routines For Running Queries 3117 ** METHOD: sqlite3 3118 ** 3119 ** This is a legacy interface that is preserved for backwards compatibility. 3120 ** Use of this interface is not recommended. 3121 ** 3122 ** Definition: A <b>result table</b> is a memory data structure created by the 3123 ** [sqlite3_get_table()] interface. A result table records the 3124 ** complete query results from one or more queries. 3125 ** 3126 ** The table conceptually has a number of rows and columns. But 3127 ** these numbers are not part of the result table itself. These 3128 ** numbers are obtained separately. Let N be the number of rows 3129 ** and M be the number of columns. 3130 ** 3131 ** A result table is an array of pointers to zero-terminated UTF-8 strings. 3132 ** There are (N+1)*M elements in the array. The first M pointers point 3133 ** to zero-terminated strings that contain the names of the columns. 3134 ** The remaining entries all point to query results. NULL values result 3135 ** in NULL pointers. All other values are in their UTF-8 zero-terminated 3136 ** string representation as returned by [sqlite3_column_text()]. 3137 ** 3138 ** A result table might consist of one or more memory allocations. 3139 ** It is not safe to pass a result table directly to [sqlite3_free()]. 3140 ** A result table should be deallocated using [sqlite3_free_table()]. 3141 ** 3142 ** ^(As an example of the result table format, suppose a query result 3143 ** is as follows: 3144 ** 3145 ** <blockquote><pre> 3146 ** Name | Age 3147 ** ----------------------- 3148 ** Alice | 43 3149 ** Bob | 28 3150 ** Cindy | 21 3151 ** </pre></blockquote> 3152 ** 3153 ** There are two columns (M==2) and three rows (N==3). Thus the 3154 ** result table has 8 entries. Suppose the result table is stored 3155 ** in an array named azResult. Then azResult holds this content: 3156 ** 3157 ** <blockquote><pre> 3158 ** azResult[0] = "Name"; 3159 ** azResult[1] = "Age"; 3160 ** azResult[2] = "Alice"; 3161 ** azResult[3] = "43"; 3162 ** azResult[4] = "Bob"; 3163 ** azResult[5] = "28"; 3164 ** azResult[6] = "Cindy"; 3165 ** azResult[7] = "21"; 3166 ** </pre></blockquote>)^ 3167 ** 3168 ** ^The sqlite3_get_table() function evaluates one or more 3169 ** semicolon-separated SQL statements in the zero-terminated UTF-8 3170 ** string of its 2nd parameter and returns a result table to the 3171 ** pointer given in its 3rd parameter. 3172 ** 3173 ** After the application has finished with the result from sqlite3_get_table(), 3174 ** it must pass the result table pointer to sqlite3_free_table() in order to 3175 ** release the memory that was malloced. Because of the way the 3176 ** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling 3177 ** function must not try to call [sqlite3_free()] directly. Only 3178 ** [sqlite3_free_table()] is able to release the memory properly and safely. 3179 ** 3180 ** The sqlite3_get_table() interface is implemented as a wrapper around 3181 ** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access 3182 ** to any internal data structures of SQLite. It uses only the public 3183 ** interface defined here. As a consequence, errors that occur in the 3184 ** wrapper layer outside of the internal [sqlite3_exec()] call are not 3185 ** reflected in subsequent calls to [sqlite3_errcode()] or 3186 ** [sqlite3_errmsg()]. 3187 */ 3188 SQLITE_API int sqlite3_get_table( 3189 sqlite3 *db, /* An open database */ 3190 const char *zSql, /* SQL to be evaluated */ 3191 char ***pazResult, /* Results of the query */ 3192 int *pnRow, /* Number of result rows written here */ 3193 int *pnColumn, /* Number of result columns written here */ 3194 char **pzErrmsg /* Error msg written here */ 3195 ); 3196 SQLITE_API void sqlite3_free_table(char **result); 3197 3198 /* 3199 ** CAPI3REF: Formatted String Printing Functions 3200 ** 3201 ** These routines are work-alikes of the "printf()" family of functions 3202 ** from the standard C library. 3203 ** These routines understand most of the common formatting options from 3204 ** the standard library printf() 3205 ** plus some additional non-standard formats ([%q], [%Q], [%w], and [%z]). 3206 ** See the [built-in printf()] documentation for details. 3207 ** 3208 ** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their 3209 ** results into memory obtained from [sqlite3_malloc64()]. 3210 ** The strings returned by these two routines should be 3211 ** released by [sqlite3_free()]. ^Both routines return a 3212 ** NULL pointer if [sqlite3_malloc64()] is unable to allocate enough 3213 ** memory to hold the resulting string. 3214 ** 3215 ** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from 3216 ** the standard C library. The result is written into the 3217 ** buffer supplied as the second parameter whose size is given by 3218 ** the first parameter. Note that the order of the 3219 ** first two parameters is reversed from snprintf().)^ This is an 3220 ** historical accident that cannot be fixed without breaking 3221 ** backwards compatibility. ^(Note also that sqlite3_snprintf() 3222 ** returns a pointer to its buffer instead of the number of 3223 ** characters actually written into the buffer.)^ We admit that 3224 ** the number of characters written would be a more useful return 3225 ** value but we cannot change the implementation of sqlite3_snprintf() 3226 ** now without breaking compatibility. 3227 ** 3228 ** ^As long as the buffer size is greater than zero, sqlite3_snprintf() 3229 ** guarantees that the buffer is always zero-terminated. ^The first 3230 ** parameter "n" is the total size of the buffer, including space for 3231 ** the zero terminator. So the longest string that can be completely 3232 ** written will be n-1 characters. 3233 ** 3234 ** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf(). 3235 ** 3236 ** See also: [built-in printf()], [printf() SQL function] 3237 */ 3238 SQLITE_API char *sqlite3_mprintf(const char*,...); 3239 SQLITE_API char *sqlite3_vmprintf(const char*, va_list); 3240 SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...); 3241 SQLITE_API char *sqlite3_vsnprintf(int,char*,const char*, va_list); 3242 3243 /* 3244 ** CAPI3REF: Memory Allocation Subsystem 3245 ** 3246 ** The SQLite core uses these three routines for all of its own 3247 ** internal memory allocation needs. "Core" in the previous sentence 3248 ** does not include operating-system specific [VFS] implementation. The 3249 ** Windows VFS uses native malloc() and free() for some operations. 3250 ** 3251 ** ^The sqlite3_malloc() routine returns a pointer to a block 3252 ** of memory at least N bytes in length, where N is the parameter. 3253 ** ^If sqlite3_malloc() is unable to obtain sufficient free 3254 ** memory, it returns a NULL pointer. ^If the parameter N to 3255 ** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns 3256 ** a NULL pointer. 3257 ** 3258 ** ^The sqlite3_malloc64(N) routine works just like 3259 ** sqlite3_malloc(N) except that N is an unsigned 64-bit integer instead 3260 ** of a signed 32-bit integer. 3261 ** 3262 ** ^Calling sqlite3_free() with a pointer previously returned 3263 ** by sqlite3_malloc() or sqlite3_realloc() releases that memory so 3264 ** that it might be reused. ^The sqlite3_free() routine is 3265 ** a no-op if it is called with a NULL pointer. Passing a NULL pointer 3266 ** to sqlite3_free() is harmless. After being freed, memory 3267 ** should neither be read nor written. Even reading previously freed 3268 ** memory might result in a segmentation fault or other severe error. 3269 ** Memory corruption, a segmentation fault, or other severe error 3270 ** might result if sqlite3_free() is called with a non-NULL pointer that 3271 ** was not obtained from sqlite3_malloc() or sqlite3_realloc(). 3272 ** 3273 ** ^The sqlite3_realloc(X,N) interface attempts to resize a 3274 ** prior memory allocation X to be at least N bytes. 3275 ** ^If the X parameter to sqlite3_realloc(X,N) 3276 ** is a NULL pointer then its behavior is identical to calling 3277 ** sqlite3_malloc(N). 3278 ** ^If the N parameter to sqlite3_realloc(X,N) is zero or 3279 ** negative then the behavior is exactly the same as calling 3280 ** sqlite3_free(X). 3281 ** ^sqlite3_realloc(X,N) returns a pointer to a memory allocation 3282 ** of at least N bytes in size or NULL if insufficient memory is available. 3283 ** ^If M is the size of the prior allocation, then min(N,M) bytes of the 3284 ** prior allocation are copied into the beginning of the buffer returned 3285 ** by sqlite3_realloc(X,N) and the prior allocation is freed. 3286 ** ^If sqlite3_realloc(X,N) returns NULL and N is positive, then the 3287 ** prior allocation is not freed. 3288 ** 3289 ** ^The sqlite3_realloc64(X,N) interface works the same as 3290 ** sqlite3_realloc(X,N) except that N is a 64-bit unsigned integer instead 3291 ** of a 32-bit signed integer. 3292 ** 3293 ** ^If X is a memory allocation previously obtained from sqlite3_malloc(), 3294 ** sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then 3295 ** sqlite3_msize(X) returns the size of that memory allocation in bytes. 3296 ** ^The value returned by sqlite3_msize(X) might be larger than the number 3297 ** of bytes requested when X was allocated. ^If X is a NULL pointer then 3298 ** sqlite3_msize(X) returns zero. If X points to something that is not 3299 ** the beginning of memory allocation, or if it points to a formerly 3300 ** valid memory allocation that has now been freed, then the behavior 3301 ** of sqlite3_msize(X) is undefined and possibly harmful. 3302 ** 3303 ** ^The memory returned by sqlite3_malloc(), sqlite3_realloc(), 3304 ** sqlite3_malloc64(), and sqlite3_realloc64() 3305 ** is always aligned to at least an 8 byte boundary, or to a 3306 ** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time 3307 ** option is used. 3308 ** 3309 ** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()] 3310 ** must be either NULL or else pointers obtained from a prior 3311 ** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have 3312 ** not yet been released. 3313 ** 3314 ** The application must not read or write any part of 3315 ** a block of memory after it has been released using 3316 ** [sqlite3_free()] or [sqlite3_realloc()]. 3317 */ 3318 SQLITE_API void *sqlite3_malloc(int); 3319 SQLITE_API void *sqlite3_malloc64(sqlite3_uint64); 3320 SQLITE_API void *sqlite3_realloc(void*, int); 3321 SQLITE_API void *sqlite3_realloc64(void*, sqlite3_uint64); 3322 SQLITE_API void sqlite3_free(void*); 3323 SQLITE_API sqlite3_uint64 sqlite3_msize(void*); 3324 3325 /* 3326 ** CAPI3REF: Memory Allocator Statistics 3327 ** 3328 ** SQLite provides these two interfaces for reporting on the status 3329 ** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()] 3330 ** routines, which form the built-in memory allocation subsystem. 3331 ** 3332 ** ^The [sqlite3_memory_used()] routine returns the number of bytes 3333 ** of memory currently outstanding (malloced but not freed). 3334 ** ^The [sqlite3_memory_highwater()] routine returns the maximum 3335 ** value of [sqlite3_memory_used()] since the high-water mark 3336 ** was last reset. ^The values returned by [sqlite3_memory_used()] and 3337 ** [sqlite3_memory_highwater()] include any overhead 3338 ** added by SQLite in its implementation of [sqlite3_malloc()], 3339 ** but not overhead added by any underlying system library 3340 ** routines that [sqlite3_malloc()] may call. 3341 ** 3342 ** ^The memory high-water mark is reset to the current value of 3343 ** [sqlite3_memory_used()] if and only if the parameter to 3344 ** [sqlite3_memory_highwater()] is true. ^The value returned 3345 ** by [sqlite3_memory_highwater(1)] is the high-water mark 3346 ** prior to the reset. 3347 */ 3348 SQLITE_API sqlite3_int64 sqlite3_memory_used(void); 3349 SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag); 3350 3351 /* 3352 ** CAPI3REF: Pseudo-Random Number Generator 3353 ** 3354 ** SQLite contains a high-quality pseudo-random number generator (PRNG) used to 3355 ** select random [ROWID | ROWIDs] when inserting new records into a table that 3356 ** already uses the largest possible [ROWID]. The PRNG is also used for 3357 ** the built-in random() and randomblob() SQL functions. This interface allows 3358 ** applications to access the same PRNG for other purposes. 3359 ** 3360 ** ^A call to this routine stores N bytes of randomness into buffer P. 3361 ** ^The P parameter can be a NULL pointer. 3362 ** 3363 ** ^If this routine has not been previously called or if the previous 3364 ** call had N less than one or a NULL pointer for P, then the PRNG is 3365 ** seeded using randomness obtained from the xRandomness method of 3366 ** the default [sqlite3_vfs] object. 3367 ** ^If the previous call to this routine had an N of 1 or more and a 3368 ** non-NULL P then the pseudo-randomness is generated 3369 ** internally and without recourse to the [sqlite3_vfs] xRandomness 3370 ** method. 3371 */ 3372 SQLITE_API void sqlite3_randomness(int N, void *P); 3373 3374 /* 3375 ** CAPI3REF: Compile-Time Authorization Callbacks 3376 ** METHOD: sqlite3 3377 ** KEYWORDS: {authorizer callback} 3378 ** 3379 ** ^This routine registers an authorizer callback with a particular 3380 ** [database connection], supplied in the first argument. 3381 ** ^The authorizer callback is invoked as SQL statements are being compiled 3382 ** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()], 3383 ** [sqlite3_prepare_v3()], [sqlite3_prepare16()], [sqlite3_prepare16_v2()], 3384 ** and [sqlite3_prepare16_v3()]. ^At various 3385 ** points during the compilation process, as logic is being created 3386 ** to perform various actions, the authorizer callback is invoked to 3387 ** see if those actions are allowed. ^The authorizer callback should 3388 ** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the 3389 ** specific action but allow the SQL statement to continue to be 3390 ** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be 3391 ** rejected with an error. ^If the authorizer callback returns 3392 ** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY] 3393 ** then the [sqlite3_prepare_v2()] or equivalent call that triggered 3394 ** the authorizer will fail with an error message. 3395 ** 3396 ** When the callback returns [SQLITE_OK], that means the operation 3397 ** requested is ok. ^When the callback returns [SQLITE_DENY], the 3398 ** [sqlite3_prepare_v2()] or equivalent call that triggered the 3399 ** authorizer will fail with an error message explaining that 3400 ** access is denied. 3401 ** 3402 ** ^The first parameter to the authorizer callback is a copy of the third 3403 ** parameter to the sqlite3_set_authorizer() interface. ^The second parameter 3404 ** to the callback is an integer [SQLITE_COPY | action code] that specifies 3405 ** the particular action to be authorized. ^The third through sixth parameters 3406 ** to the callback are either NULL pointers or zero-terminated strings 3407 ** that contain additional details about the action to be authorized. 3408 ** Applications must always be prepared to encounter a NULL pointer in any 3409 ** of the third through the sixth parameters of the authorization callback. 3410 ** 3411 ** ^If the action code is [SQLITE_READ] 3412 ** and the callback returns [SQLITE_IGNORE] then the 3413 ** [prepared statement] statement is constructed to substitute 3414 ** a NULL value in place of the table column that would have 3415 ** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE] 3416 ** return can be used to deny an untrusted user access to individual 3417 ** columns of a table. 3418 ** ^When a table is referenced by a [SELECT] but no column values are 3419 ** extracted from that table (for example in a query like 3420 ** "SELECT count(*) FROM tab") then the [SQLITE_READ] authorizer callback 3421 ** is invoked once for that table with a column name that is an empty string. 3422 ** ^If the action code is [SQLITE_DELETE] and the callback returns 3423 ** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the 3424 ** [truncate optimization] is disabled and all rows are deleted individually. 3425 ** 3426 ** An authorizer is used when [sqlite3_prepare | preparing] 3427 ** SQL statements from an untrusted source, to ensure that the SQL statements 3428 ** do not try to access data they are not allowed to see, or that they do not 3429 ** try to execute malicious statements that damage the database. For 3430 ** example, an application may allow a user to enter arbitrary 3431 ** SQL queries for evaluation by a database. But the application does 3432 ** not want the user to be able to make arbitrary changes to the 3433 ** database. An authorizer could then be put in place while the 3434 ** user-entered SQL is being [sqlite3_prepare | prepared] that 3435 ** disallows everything except [SELECT] statements. 3436 ** 3437 ** Applications that need to process SQL from untrusted sources 3438 ** might also consider lowering resource limits using [sqlite3_limit()] 3439 ** and limiting database size using the [max_page_count] [PRAGMA] 3440 ** in addition to using an authorizer. 3441 ** 3442 ** ^(Only a single authorizer can be in place on a database connection 3443 ** at a time. Each call to sqlite3_set_authorizer overrides the 3444 ** previous call.)^ ^Disable the authorizer by installing a NULL callback. 3445 ** The authorizer is disabled by default. 3446 ** 3447 ** The authorizer callback must not do anything that will modify 3448 ** the database connection that invoked the authorizer callback. 3449 ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their 3450 ** database connections for the meaning of "modify" in this paragraph. 3451 ** 3452 ** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the 3453 ** statement might be re-prepared during [sqlite3_step()] due to a 3454 ** schema change. Hence, the application should ensure that the 3455 ** correct authorizer callback remains in place during the [sqlite3_step()]. 3456 ** 3457 ** ^Note that the authorizer callback is invoked only during 3458 ** [sqlite3_prepare()] or its variants. Authorization is not 3459 ** performed during statement evaluation in [sqlite3_step()], unless 3460 ** as stated in the previous paragraph, sqlite3_step() invokes 3461 ** sqlite3_prepare_v2() to reprepare a statement after a schema change. 3462 */ 3463 SQLITE_API int sqlite3_set_authorizer( 3464 sqlite3*, 3465 int (*xAuth)(void*,int,const char*,const char*,const char*,const char*), 3466 void *pUserData 3467 ); 3468 3469 /* 3470 ** CAPI3REF: Authorizer Return Codes 3471 ** 3472 ** The [sqlite3_set_authorizer | authorizer callback function] must 3473 ** return either [SQLITE_OK] or one of these two constants in order 3474 ** to signal SQLite whether or not the action is permitted. See the 3475 ** [sqlite3_set_authorizer | authorizer documentation] for additional 3476 ** information. 3477 ** 3478 ** Note that SQLITE_IGNORE is also used as a [conflict resolution mode] 3479 ** returned from the [sqlite3_vtab_on_conflict()] interface. 3480 */ 3481 #define SQLITE_DENY 1 /* Abort the SQL statement with an error */ 3482 #define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */ 3483 3484 /* 3485 ** CAPI3REF: Authorizer Action Codes 3486 ** 3487 ** The [sqlite3_set_authorizer()] interface registers a callback function 3488 ** that is invoked to authorize certain SQL statement actions. The 3489 ** second parameter to the callback is an integer code that specifies 3490 ** what action is being authorized. These are the integer action codes that 3491 ** the authorizer callback may be passed. 3492 ** 3493 ** These action code values signify what kind of operation is to be 3494 ** authorized. The 3rd and 4th parameters to the authorization 3495 ** callback function will be parameters or NULL depending on which of these 3496 ** codes is used as the second parameter. ^(The 5th parameter to the 3497 ** authorizer callback is the name of the database ("main", "temp", 3498 ** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback 3499 ** is the name of the inner-most trigger or view that is responsible for 3500 ** the access attempt or NULL if this access attempt is directly from 3501 ** top-level SQL code. 3502 */ 3503 /******************************************* 3rd ************ 4th ***********/ 3504 #define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */ 3505 #define SQLITE_CREATE_TABLE 2 /* Table Name NULL */ 3506 #define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */ 3507 #define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */ 3508 #define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */ 3509 #define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */ 3510 #define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */ 3511 #define SQLITE_CREATE_VIEW 8 /* View Name NULL */ 3512 #define SQLITE_DELETE 9 /* Table Name NULL */ 3513 #define SQLITE_DROP_INDEX 10 /* Index Name Table Name */ 3514 #define SQLITE_DROP_TABLE 11 /* Table Name NULL */ 3515 #define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */ 3516 #define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */ 3517 #define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */ 3518 #define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */ 3519 #define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */ 3520 #define SQLITE_DROP_VIEW 17 /* View Name NULL */ 3521 #define SQLITE_INSERT 18 /* Table Name NULL */ 3522 #define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */ 3523 #define SQLITE_READ 20 /* Table Name Column Name */ 3524 #define SQLITE_SELECT 21 /* NULL NULL */ 3525 #define SQLITE_TRANSACTION 22 /* Operation NULL */ 3526 #define SQLITE_UPDATE 23 /* Table Name Column Name */ 3527 #define SQLITE_ATTACH 24 /* Filename NULL */ 3528 #define SQLITE_DETACH 25 /* Database Name NULL */ 3529 #define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */ 3530 #define SQLITE_REINDEX 27 /* Index Name NULL */ 3531 #define SQLITE_ANALYZE 28 /* Table Name NULL */ 3532 #define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */ 3533 #define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */ 3534 #define SQLITE_FUNCTION 31 /* NULL Function Name */ 3535 #define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */ 3536 #define SQLITE_COPY 0 /* No longer used */ 3537 #define SQLITE_RECURSIVE 33 /* NULL NULL */ 3538 3539 /* 3540 ** CAPI3REF: Deprecated Tracing And Profiling Functions 3541 ** DEPRECATED 3542 ** 3543 ** These routines are deprecated. Use the [sqlite3_trace_v2()] interface 3544 ** instead of the routines described here. 3545 ** 3546 ** These routines register callback functions that can be used for 3547 ** tracing and profiling the execution of SQL statements. 3548 ** 3549 ** ^The callback function registered by sqlite3_trace() is invoked at 3550 ** various times when an SQL statement is being run by [sqlite3_step()]. 3551 ** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the 3552 ** SQL statement text as the statement first begins executing. 3553 ** ^(Additional sqlite3_trace() callbacks might occur 3554 ** as each triggered subprogram is entered. The callbacks for triggers 3555 ** contain a UTF-8 SQL comment that identifies the trigger.)^ 3556 ** 3557 ** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit 3558 ** the length of [bound parameter] expansion in the output of sqlite3_trace(). 3559 ** 3560 ** ^The callback function registered by sqlite3_profile() is invoked 3561 ** as each SQL statement finishes. ^The profile callback contains 3562 ** the original statement text and an estimate of wall-clock time 3563 ** of how long that statement took to run. ^The profile callback 3564 ** time is in units of nanoseconds, however the current implementation 3565 ** is only capable of millisecond resolution so the six least significant 3566 ** digits in the time are meaningless. Future versions of SQLite 3567 ** might provide greater resolution on the profiler callback. Invoking 3568 ** either [sqlite3_trace()] or [sqlite3_trace_v2()] will cancel the 3569 ** profile callback. 3570 */ 3571 SQLITE_API SQLITE_DEPRECATED void *sqlite3_trace(sqlite3*, 3572 void(*xTrace)(void*,const char*), void*); 3573 SQLITE_API SQLITE_DEPRECATED void *sqlite3_profile(sqlite3*, 3574 void(*xProfile)(void*,const char*,sqlite3_uint64), void*); 3575 3576 /* 3577 ** CAPI3REF: SQL Trace Event Codes 3578 ** KEYWORDS: SQLITE_TRACE 3579 ** 3580 ** These constants identify classes of events that can be monitored 3581 ** using the [sqlite3_trace_v2()] tracing logic. The M argument 3582 ** to [sqlite3_trace_v2(D,M,X,P)] is an OR-ed combination of one or more of 3583 ** the following constants. ^The first argument to the trace callback 3584 ** is one of the following constants. 3585 ** 3586 ** New tracing constants may be added in future releases. 3587 ** 3588 ** ^A trace callback has four arguments: xCallback(T,C,P,X). 3589 ** ^The T argument is one of the integer type codes above. 3590 ** ^The C argument is a copy of the context pointer passed in as the 3591 ** fourth argument to [sqlite3_trace_v2()]. 3592 ** The P and X arguments are pointers whose meanings depend on T. 3593 ** 3594 ** <dl> 3595 ** [[SQLITE_TRACE_STMT]] <dt>SQLITE_TRACE_STMT</dt> 3596 ** <dd>^An SQLITE_TRACE_STMT callback is invoked when a prepared statement 3597 ** first begins running and possibly at other times during the 3598 ** execution of the prepared statement, such as at the start of each 3599 ** trigger subprogram. ^The P argument is a pointer to the 3600 ** [prepared statement]. ^The X argument is a pointer to a string which 3601 ** is the unexpanded SQL text of the prepared statement or an SQL comment 3602 ** that indicates the invocation of a trigger. ^The callback can compute 3603 ** the same text that would have been returned by the legacy [sqlite3_trace()] 3604 ** interface by using the X argument when X begins with "--" and invoking 3605 ** [sqlite3_expanded_sql(P)] otherwise. 3606 ** 3607 ** [[SQLITE_TRACE_PROFILE]] <dt>SQLITE_TRACE_PROFILE</dt> 3608 ** <dd>^An SQLITE_TRACE_PROFILE callback provides approximately the same 3609 ** information as is provided by the [sqlite3_profile()] callback. 3610 ** ^The P argument is a pointer to the [prepared statement] and the 3611 ** X argument points to a 64-bit integer which is approximately 3612 ** the number of nanoseconds that the prepared statement took to run. 3613 ** ^The SQLITE_TRACE_PROFILE callback is invoked when the statement finishes. 3614 ** 3615 ** [[SQLITE_TRACE_ROW]] <dt>SQLITE_TRACE_ROW</dt> 3616 ** <dd>^An SQLITE_TRACE_ROW callback is invoked whenever a prepared 3617 ** statement generates a single row of result. 3618 ** ^The P argument is a pointer to the [prepared statement] and the 3619 ** X argument is unused. 3620 ** 3621 ** [[SQLITE_TRACE_CLOSE]] <dt>SQLITE_TRACE_CLOSE</dt> 3622 ** <dd>^An SQLITE_TRACE_CLOSE callback is invoked when a database 3623 ** connection closes. 3624 ** ^The P argument is a pointer to the [database connection] object 3625 ** and the X argument is unused. 3626 ** </dl> 3627 */ 3628 #define SQLITE_TRACE_STMT 0x01 3629 #define SQLITE_TRACE_PROFILE 0x02 3630 #define SQLITE_TRACE_ROW 0x04 3631 #define SQLITE_TRACE_CLOSE 0x08 3632 3633 /* 3634 ** CAPI3REF: SQL Trace Hook 3635 ** METHOD: sqlite3 3636 ** 3637 ** ^The sqlite3_trace_v2(D,M,X,P) interface registers a trace callback 3638 ** function X against [database connection] D, using property mask M 3639 ** and context pointer P. ^If the X callback is 3640 ** NULL or if the M mask is zero, then tracing is disabled. The 3641 ** M argument should be the bitwise OR-ed combination of 3642 ** zero or more [SQLITE_TRACE] constants. 3643 ** 3644 ** ^Each call to either sqlite3_trace(D,X,P) or sqlite3_trace_v2(D,M,X,P) 3645 ** overrides (cancels) all prior calls to sqlite3_trace(D,X,P) or 3646 ** sqlite3_trace_v2(D,M,X,P) for the [database connection] D. Each 3647 ** database connection may have at most one trace callback. 3648 ** 3649 ** ^The X callback is invoked whenever any of the events identified by 3650 ** mask M occur. ^The integer return value from the callback is currently 3651 ** ignored, though this may change in future releases. Callback 3652 ** implementations should return zero to ensure future compatibility. 3653 ** 3654 ** ^A trace callback is invoked with four arguments: callback(T,C,P,X). 3655 ** ^The T argument is one of the [SQLITE_TRACE] 3656 ** constants to indicate why the callback was invoked. 3657 ** ^The C argument is a copy of the context pointer. 3658 ** The P and X arguments are pointers whose meanings depend on T. 3659 ** 3660 ** The sqlite3_trace_v2() interface is intended to replace the legacy 3661 ** interfaces [sqlite3_trace()] and [sqlite3_profile()], both of which 3662 ** are deprecated. 3663 */ 3664 SQLITE_API int sqlite3_trace_v2( 3665 sqlite3*, 3666 unsigned uMask, 3667 int(*xCallback)(unsigned,void*,void*,void*), 3668 void *pCtx 3669 ); 3670 3671 /* 3672 ** CAPI3REF: Query Progress Callbacks 3673 ** METHOD: sqlite3 3674 ** 3675 ** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback 3676 ** function X to be invoked periodically during long running calls to 3677 ** [sqlite3_step()] and [sqlite3_prepare()] and similar for 3678 ** database connection D. An example use for this 3679 ** interface is to keep a GUI updated during a large query. 3680 ** 3681 ** ^The parameter P is passed through as the only parameter to the 3682 ** callback function X. ^The parameter N is the approximate number of 3683 ** [virtual machine instructions] that are evaluated between successive 3684 ** invocations of the callback X. ^If N is less than one then the progress 3685 ** handler is disabled. 3686 ** 3687 ** ^Only a single progress handler may be defined at one time per 3688 ** [database connection]; setting a new progress handler cancels the 3689 ** old one. ^Setting parameter X to NULL disables the progress handler. 3690 ** ^The progress handler is also disabled by setting N to a value less 3691 ** than 1. 3692 ** 3693 ** ^If the progress callback returns non-zero, the operation is 3694 ** interrupted. This feature can be used to implement a 3695 ** "Cancel" button on a GUI progress dialog box. 3696 ** 3697 ** The progress handler callback must not do anything that will modify 3698 ** the database connection that invoked the progress handler. 3699 ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their 3700 ** database connections for the meaning of "modify" in this paragraph. 3701 ** 3702 ** The progress handler callback would originally only be invoked from the 3703 ** bytecode engine. It still might be invoked during [sqlite3_prepare()] 3704 ** and similar because those routines might force a reparse of the schema 3705 ** which involves running the bytecode engine. However, beginning with 3706 ** SQLite version 3.41.0, the progress handler callback might also be 3707 ** invoked directly from [sqlite3_prepare()] while analyzing and generating 3708 ** code for complex queries. 3709 */ 3710 SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*); 3711 3712 /* 3713 ** CAPI3REF: Opening A New Database Connection 3714 ** CONSTRUCTOR: sqlite3 3715 ** 3716 ** ^These routines open an SQLite database file as specified by the 3717 ** filename argument. ^The filename argument is interpreted as UTF-8 for 3718 ** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte 3719 ** order for sqlite3_open16(). ^(A [database connection] handle is usually 3720 ** returned in *ppDb, even if an error occurs. The only exception is that 3721 ** if SQLite is unable to allocate memory to hold the [sqlite3] object, 3722 ** a NULL will be written into *ppDb instead of a pointer to the [sqlite3] 3723 ** object.)^ ^(If the database is opened (and/or created) successfully, then 3724 ** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The 3725 ** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain 3726 ** an English language description of the error following a failure of any 3727 ** of the sqlite3_open() routines. 3728 ** 3729 ** ^The default encoding will be UTF-8 for databases created using 3730 ** sqlite3_open() or sqlite3_open_v2(). ^The default encoding for databases 3731 ** created using sqlite3_open16() will be UTF-16 in the native byte order. 3732 ** 3733 ** Whether or not an error occurs when it is opened, resources 3734 ** associated with the [database connection] handle should be released by 3735 ** passing it to [sqlite3_close()] when it is no longer required. 3736 ** 3737 ** The sqlite3_open_v2() interface works like sqlite3_open() 3738 ** except that it accepts two additional parameters for additional control 3739 ** over the new database connection. ^(The flags parameter to 3740 ** sqlite3_open_v2() must include, at a minimum, one of the following 3741 ** three flag combinations:)^ 3742 ** 3743 ** <dl> 3744 ** ^(<dt>[SQLITE_OPEN_READONLY]</dt> 3745 ** <dd>The database is opened in read-only mode. If the database does 3746 ** not already exist, an error is returned.</dd>)^ 3747 ** 3748 ** ^(<dt>[SQLITE_OPEN_READWRITE]</dt> 3749 ** <dd>The database is opened for reading and writing if possible, or 3750 ** reading only if the file is write protected by the operating 3751 ** system. In either case the database must already exist, otherwise 3752 ** an error is returned. For historical reasons, if opening in 3753 ** read-write mode fails due to OS-level permissions, an attempt is 3754 ** made to open it in read-only mode. [sqlite3_db_readonly()] can be 3755 ** used to determine whether the database is actually 3756 ** read-write.</dd>)^ 3757 ** 3758 ** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt> 3759 ** <dd>The database is opened for reading and writing, and is created if 3760 ** it does not already exist. This is the behavior that is always used for 3761 ** sqlite3_open() and sqlite3_open16().</dd>)^ 3762 ** </dl> 3763 ** 3764 ** In addition to the required flags, the following optional flags are 3765 ** also supported: 3766 ** 3767 ** <dl> 3768 ** ^(<dt>[SQLITE_OPEN_URI]</dt> 3769 ** <dd>The filename can be interpreted as a URI if this flag is set.</dd>)^ 3770 ** 3771 ** ^(<dt>[SQLITE_OPEN_MEMORY]</dt> 3772 ** <dd>The database will be opened as an in-memory database. The database 3773 ** is named by the "filename" argument for the purposes of cache-sharing, 3774 ** if shared cache mode is enabled, but the "filename" is otherwise ignored. 3775 ** </dd>)^ 3776 ** 3777 ** ^(<dt>[SQLITE_OPEN_NOMUTEX]</dt> 3778 ** <dd>The new database connection will use the "multi-thread" 3779 ** [threading mode].)^ This means that separate threads are allowed 3780 ** to use SQLite at the same time, as long as each thread is using 3781 ** a different [database connection]. 3782 ** 3783 ** ^(<dt>[SQLITE_OPEN_FULLMUTEX]</dt> 3784 ** <dd>The new database connection will use the "serialized" 3785 ** [threading mode].)^ This means the multiple threads can safely 3786 ** attempt to use the same database connection at the same time. 3787 ** (Mutexes will block any actual concurrency, but in this mode 3788 ** there is no harm in trying.) 3789 ** 3790 ** ^(<dt>[SQLITE_OPEN_SHAREDCACHE]</dt> 3791 ** <dd>The database is opened with [shared cache] enabled, overriding 3792 ** the default shared cache setting provided by 3793 ** [sqlite3_enable_shared_cache()].)^ 3794 ** The [use of shared cache mode is discouraged] and hence shared cache 3795 ** capabilities may be omitted from many builds of SQLite. In such cases, 3796 ** this option is a no-op. 3797 ** 3798 ** ^(<dt>[SQLITE_OPEN_PRIVATECACHE]</dt> 3799 ** <dd>The database is opened with [shared cache] disabled, overriding 3800 ** the default shared cache setting provided by 3801 ** [sqlite3_enable_shared_cache()].)^ 3802 ** 3803 ** [[OPEN_EXRESCODE]] ^(<dt>[SQLITE_OPEN_EXRESCODE]</dt> 3804 ** <dd>The database connection comes up in "extended result code mode". 3805 ** In other words, the database behaves as if 3806 ** [sqlite3_extended_result_codes(db,1)] were called on the database 3807 ** connection as soon as the connection is created. In addition to setting 3808 ** the extended result code mode, this flag also causes [sqlite3_open_v2()] 3809 ** to return an extended result code.</dd> 3810 ** 3811 ** [[OPEN_NOFOLLOW]] ^(<dt>[SQLITE_OPEN_NOFOLLOW]</dt> 3812 ** <dd>The database filename is not allowed to contain a symbolic link</dd> 3813 ** </dl>)^ 3814 ** 3815 ** If the 3rd parameter to sqlite3_open_v2() is not one of the 3816 ** required combinations shown above optionally combined with other 3817 ** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits] 3818 ** then the behavior is undefined. Historic versions of SQLite 3819 ** have silently ignored surplus bits in the flags parameter to 3820 ** sqlite3_open_v2(), however that behavior might not be carried through 3821 ** into future versions of SQLite and so applications should not rely 3822 ** upon it. Note in particular that the SQLITE_OPEN_EXCLUSIVE flag is a no-op 3823 ** for sqlite3_open_v2(). The SQLITE_OPEN_EXCLUSIVE does *not* cause 3824 ** the open to fail if the database already exists. The SQLITE_OPEN_EXCLUSIVE 3825 ** flag is intended for use by the [sqlite3_vfs|VFS interface] only, and not 3826 ** by sqlite3_open_v2(). 3827 ** 3828 ** ^The fourth parameter to sqlite3_open_v2() is the name of the 3829 ** [sqlite3_vfs] object that defines the operating system interface that 3830 ** the new database connection should use. ^If the fourth parameter is 3831 ** a NULL pointer then the default [sqlite3_vfs] object is used. 3832 ** 3833 ** ^If the filename is ":memory:", then a private, temporary in-memory database 3834 ** is created for the connection. ^This in-memory database will vanish when 3835 ** the database connection is closed. Future versions of SQLite might 3836 ** make use of additional special filenames that begin with the ":" character. 3837 ** It is recommended that when a database filename actually does begin with 3838 ** a ":" character you should prefix the filename with a pathname such as 3839 ** "./" to avoid ambiguity. 3840 ** 3841 ** ^If the filename is an empty string, then a private, temporary 3842 ** on-disk database will be created. ^This private database will be 3843 ** automatically deleted as soon as the database connection is closed. 3844 ** 3845 ** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3> 3846 ** 3847 ** ^If [URI filename] interpretation is enabled, and the filename argument 3848 ** begins with "file:", then the filename is interpreted as a URI. ^URI 3849 ** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is 3850 ** set in the third argument to sqlite3_open_v2(), or if it has 3851 ** been enabled globally using the [SQLITE_CONFIG_URI] option with the 3852 ** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option. 3853 ** URI filename interpretation is turned off 3854 ** by default, but future releases of SQLite might enable URI filename 3855 ** interpretation by default. See "[URI filenames]" for additional 3856 ** information. 3857 ** 3858 ** URI filenames are parsed according to RFC 3986. ^If the URI contains an 3859 ** authority, then it must be either an empty string or the string 3860 ** "localhost". ^If the authority is not an empty string or "localhost", an 3861 ** error is returned to the caller. ^The fragment component of a URI, if 3862 ** present, is ignored. 3863 ** 3864 ** ^SQLite uses the path component of the URI as the name of the disk file 3865 ** which contains the database. ^If the path begins with a '/' character, 3866 ** then it is interpreted as an absolute path. ^If the path does not begin 3867 ** with a '/' (meaning that the authority section is omitted from the URI) 3868 ** then the path is interpreted as a relative path. 3869 ** ^(On windows, the first component of an absolute path 3870 ** is a drive specification (e.g. "C:").)^ 3871 ** 3872 ** [[core URI query parameters]] 3873 ** The query component of a URI may contain parameters that are interpreted 3874 ** either by SQLite itself, or by a [VFS | custom VFS implementation]. 3875 ** SQLite and its built-in [VFSes] interpret the 3876 ** following query parameters: 3877 ** 3878 ** <ul> 3879 ** <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of 3880 ** a VFS object that provides the operating system interface that should 3881 ** be used to access the database file on disk. ^If this option is set to 3882 ** an empty string the default VFS object is used. ^Specifying an unknown 3883 ** VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is 3884 ** present, then the VFS specified by the option takes precedence over 3885 ** the value passed as the fourth parameter to sqlite3_open_v2(). 3886 ** 3887 ** <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw", 3888 ** "rwc", or "memory". Attempting to set it to any other value is 3889 ** an error)^. 3890 ** ^If "ro" is specified, then the database is opened for read-only 3891 ** access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the 3892 ** third argument to sqlite3_open_v2(). ^If the mode option is set to 3893 ** "rw", then the database is opened for read-write (but not create) 3894 ** access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had 3895 ** been set. ^Value "rwc" is equivalent to setting both 3896 ** SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE. ^If the mode option is 3897 ** set to "memory" then a pure [in-memory database] that never reads 3898 ** or writes from disk is used. ^It is an error to specify a value for 3899 ** the mode parameter that is less restrictive than that specified by 3900 ** the flags passed in the third parameter to sqlite3_open_v2(). 3901 ** 3902 ** <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or 3903 ** "private". ^Setting it to "shared" is equivalent to setting the 3904 ** SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to 3905 ** sqlite3_open_v2(). ^Setting the cache parameter to "private" is 3906 ** equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit. 3907 ** ^If sqlite3_open_v2() is used and the "cache" parameter is present in 3908 ** a URI filename, its value overrides any behavior requested by setting 3909 ** SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag. 3910 ** 3911 ** <li> <b>psow</b>: ^The psow parameter indicates whether or not the 3912 ** [powersafe overwrite] property does or does not apply to the 3913 ** storage media on which the database file resides. 3914 ** 3915 ** <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter 3916 ** which if set disables file locking in rollback journal modes. This 3917 ** is useful for accessing a database on a filesystem that does not 3918 ** support locking. Caution: Database corruption might result if two 3919 ** or more processes write to the same database and any one of those 3920 ** processes uses nolock=1. 3921 ** 3922 ** <li> <b>immutable</b>: ^The immutable parameter is a boolean query 3923 ** parameter that indicates that the database file is stored on 3924 ** read-only media. ^When immutable is set, SQLite assumes that the 3925 ** database file cannot be changed, even by a process with higher 3926 ** privilege, and so the database is opened read-only and all locking 3927 ** and change detection is disabled. Caution: Setting the immutable 3928 ** property on a database file that does in fact change can result 3929 ** in incorrect query results and/or [SQLITE_CORRUPT] errors. 3930 ** See also: [SQLITE_IOCAP_IMMUTABLE]. 3931 ** 3932 ** </ul> 3933 ** 3934 ** ^Specifying an unknown parameter in the query component of a URI is not an 3935 ** error. Future versions of SQLite might understand additional query 3936 ** parameters. See "[query parameters with special meaning to SQLite]" for 3937 ** additional information. 3938 ** 3939 ** [[URI filename examples]] <h3>URI filename examples</h3> 3940 ** 3941 ** <table border="1" align=center cellpadding=5> 3942 ** <tr><th> URI filenames <th> Results 3943 ** <tr><td> file:data.db <td> 3944 ** Open the file "data.db" in the current directory. 3945 ** <tr><td> file:/home/fred/data.db<br> 3946 ** file:///home/fred/data.db <br> 3947 ** file://localhost/home/fred/data.db <br> <td> 3948 ** Open the database file "/home/fred/data.db". 3949 ** <tr><td> file://darkstar/home/fred/data.db <td> 3950 ** An error. "darkstar" is not a recognized authority. 3951 ** <tr><td style="white-space:nowrap"> 3952 ** file:///C:/Documents%20and%20Settings/fred/Desktop/data.db 3953 ** <td> Windows only: Open the file "data.db" on fred's desktop on drive 3954 ** C:. Note that the %20 escaping in this example is not strictly 3955 ** necessary - space characters can be used literally 3956 ** in URI filenames. 3957 ** <tr><td> file:data.db?mode=ro&cache=private <td> 3958 ** Open file "data.db" in the current directory for read-only access. 3959 ** Regardless of whether or not shared-cache mode is enabled by 3960 ** default, use a private cache. 3961 ** <tr><td> file:/home/fred/data.db?vfs=unix-dotfile <td> 3962 ** Open file "/home/fred/data.db". Use the special VFS "unix-dotfile" 3963 ** that uses dot-files in place of posix advisory locking. 3964 ** <tr><td> file:data.db?mode=readonly <td> 3965 ** An error. "readonly" is not a valid option for the "mode" parameter. 3966 ** Use "ro" instead: "file:data.db?mode=ro". 3967 ** </table> 3968 ** 3969 ** ^URI hexadecimal escape sequences (%HH) are supported within the path and 3970 ** query components of a URI. A hexadecimal escape sequence consists of a 3971 ** percent sign - "%" - followed by exactly two hexadecimal digits 3972 ** specifying an octet value. ^Before the path or query components of a 3973 ** URI filename are interpreted, they are encoded using UTF-8 and all 3974 ** hexadecimal escape sequences replaced by a single byte containing the 3975 ** corresponding octet. If this process generates an invalid UTF-8 encoding, 3976 ** the results are undefined. 3977 ** 3978 ** <b>Note to Windows users:</b> The encoding used for the filename argument 3979 ** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever 3980 ** codepage is currently defined. Filenames containing international 3981 ** characters must be converted to UTF-8 prior to passing them into 3982 ** sqlite3_open() or sqlite3_open_v2(). 3983 ** 3984 ** <b>Note to Windows Runtime users:</b> The temporary directory must be set 3985 ** prior to calling sqlite3_open() or sqlite3_open_v2(). Otherwise, various 3986 ** features that require the use of temporary files may fail. 3987 ** 3988 ** See also: [sqlite3_temp_directory] 3989 */ 3990 SQLITE_API int sqlite3_open( 3991 const char *filename, /* Database filename (UTF-8) */ 3992 sqlite3 **ppDb /* OUT: SQLite db handle */ 3993 ); 3994 SQLITE_API int sqlite3_open16( 3995 const void *filename, /* Database filename (UTF-16) */ 3996 sqlite3 **ppDb /* OUT: SQLite db handle */ 3997 ); 3998 SQLITE_API int sqlite3_open_v2( 3999 const char *filename, /* Database filename (UTF-8) */ 4000 sqlite3 **ppDb, /* OUT: SQLite db handle */ 4001 int flags, /* Flags */ 4002 const char *zVfs /* Name of VFS module to use */ 4003 ); 4004 4005 /* 4006 ** CAPI3REF: Obtain Values For URI Parameters 4007 ** 4008 ** These are utility routines, useful to [VFS|custom VFS implementations], 4009 ** that check if a database file was a URI that contained a specific query 4010 ** parameter, and if so obtains the value of that query parameter. 4011 ** 4012 ** The first parameter to these interfaces (hereafter referred to 4013 ** as F) must be one of: 4014 ** <ul> 4015 ** <li> A database filename pointer created by the SQLite core and 4016 ** passed into the xOpen() method of a VFS implementation, or 4017 ** <li> A filename obtained from [sqlite3_db_filename()], or 4018 ** <li> A new filename constructed using [sqlite3_create_filename()]. 4019 ** </ul> 4020 ** If the F parameter is not one of the above, then the behavior is 4021 ** undefined and probably undesirable. Older versions of SQLite were 4022 ** more tolerant of invalid F parameters than newer versions. 4023 ** 4024 ** If F is a suitable filename (as described in the previous paragraph) 4025 ** and if P is the name of the query parameter, then 4026 ** sqlite3_uri_parameter(F,P) returns the value of the P 4027 ** parameter if it exists or a NULL pointer if P does not appear as a 4028 ** query parameter on F. If P is a query parameter of F and it 4029 ** has no explicit value, then sqlite3_uri_parameter(F,P) returns 4030 ** a pointer to an empty string. 4031 ** 4032 ** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean 4033 ** parameter and returns true (1) or false (0) according to the value 4034 ** of P. The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the 4035 ** value of query parameter P is one of "yes", "true", or "on" in any 4036 ** case or if the value begins with a non-zero number. The 4037 ** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of 4038 ** query parameter P is one of "no", "false", or "off" in any case or 4039 ** if the value begins with a numeric zero. If P is not a query 4040 ** parameter on F or if the value of P does not match any of the 4041 ** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0). 4042 ** 4043 ** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a 4044 ** 64-bit signed integer and returns that integer, or D if P does not 4045 ** exist. If the value of P is something other than an integer, then 4046 ** zero is returned. 4047 ** 4048 ** The sqlite3_uri_key(F,N) returns a pointer to the name (not 4049 ** the value) of the N-th query parameter for filename F, or a NULL 4050 ** pointer if N is less than zero or greater than the number of query 4051 ** parameters minus 1. The N value is zero-based so N should be 0 to obtain 4052 ** the name of the first query parameter, 1 for the second parameter, and 4053 ** so forth. 4054 ** 4055 ** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and 4056 ** sqlite3_uri_boolean(F,P,B) returns B. If F is not a NULL pointer and 4057 ** is not a database file pathname pointer that the SQLite core passed 4058 ** into the xOpen VFS method, then the behavior of this routine is undefined 4059 ** and probably undesirable. 4060 ** 4061 ** Beginning with SQLite [version 3.31.0] ([dateof:3.31.0]) the input F 4062 ** parameter can also be the name of a rollback journal file or WAL file 4063 ** in addition to the main database file. Prior to version 3.31.0, these 4064 ** routines would only work if F was the name of the main database file. 4065 ** When the F parameter is the name of the rollback journal or WAL file, 4066 ** it has access to all the same query parameters as were found on the 4067 ** main database file. 4068 ** 4069 ** See the [URI filename] documentation for additional information. 4070 */ 4071 SQLITE_API const char *sqlite3_uri_parameter(sqlite3_filename z, const char *zParam); 4072 SQLITE_API int sqlite3_uri_boolean(sqlite3_filename z, const char *zParam, int bDefault); 4073 SQLITE_API sqlite3_int64 sqlite3_uri_int64(sqlite3_filename, const char*, sqlite3_int64); 4074 SQLITE_API const char *sqlite3_uri_key(sqlite3_filename z, int N); 4075 4076 /* 4077 ** CAPI3REF: Translate filenames 4078 ** 4079 ** These routines are available to [VFS|custom VFS implementations] for 4080 ** translating filenames between the main database file, the journal file, 4081 ** and the WAL file. 4082 ** 4083 ** If F is the name of an sqlite database file, journal file, or WAL file 4084 ** passed by the SQLite core into the VFS, then sqlite3_filename_database(F) 4085 ** returns the name of the corresponding database file. 4086 ** 4087 ** If F is the name of an sqlite database file, journal file, or WAL file 4088 ** passed by the SQLite core into the VFS, or if F is a database filename 4089 ** obtained from [sqlite3_db_filename()], then sqlite3_filename_journal(F) 4090 ** returns the name of the corresponding rollback journal file. 4091 ** 4092 ** If F is the name of an sqlite database file, journal file, or WAL file 4093 ** that was passed by the SQLite core into the VFS, or if F is a database 4094 ** filename obtained from [sqlite3_db_filename()], then 4095 ** sqlite3_filename_wal(F) returns the name of the corresponding 4096 ** WAL file. 4097 ** 4098 ** In all of the above, if F is not the name of a database, journal or WAL 4099 ** filename passed into the VFS from the SQLite core and F is not the 4100 ** return value from [sqlite3_db_filename()], then the result is 4101 ** undefined and is likely a memory access violation. 4102 */ 4103 SQLITE_API const char *sqlite3_filename_database(sqlite3_filename); 4104 SQLITE_API const char *sqlite3_filename_journal(sqlite3_filename); 4105 SQLITE_API const char *sqlite3_filename_wal(sqlite3_filename); 4106 4107 /* 4108 ** CAPI3REF: Database File Corresponding To A Journal 4109 ** 4110 ** ^If X is the name of a rollback or WAL-mode journal file that is 4111 ** passed into the xOpen method of [sqlite3_vfs], then 4112 ** sqlite3_database_file_object(X) returns a pointer to the [sqlite3_file] 4113 ** object that represents the main database file. 4114 ** 4115 ** This routine is intended for use in custom [VFS] implementations 4116 ** only. It is not a general-purpose interface. 4117 ** The argument sqlite3_file_object(X) must be a filename pointer that 4118 ** has been passed into [sqlite3_vfs].xOpen method where the 4119 ** flags parameter to xOpen contains one of the bits 4120 ** [SQLITE_OPEN_MAIN_JOURNAL] or [SQLITE_OPEN_WAL]. Any other use 4121 ** of this routine results in undefined and probably undesirable 4122 ** behavior. 4123 */ 4124 SQLITE_API sqlite3_file *sqlite3_database_file_object(const char*); 4125 4126 /* 4127 ** CAPI3REF: Create and Destroy VFS Filenames 4128 ** 4129 ** These interfaces are provided for use by [VFS shim] implementations and 4130 ** are not useful outside of that context. 4131 ** 4132 ** The sqlite3_create_filename(D,J,W,N,P) allocates memory to hold a version of 4133 ** database filename D with corresponding journal file J and WAL file W and 4134 ** an array P of N URI Key/Value pairs. The result from 4135 ** sqlite3_create_filename(D,J,W,N,P) is a pointer to a database filename that 4136 ** is safe to pass to routines like: 4137 ** <ul> 4138 ** <li> [sqlite3_uri_parameter()], 4139 ** <li> [sqlite3_uri_boolean()], 4140 ** <li> [sqlite3_uri_int64()], 4141 ** <li> [sqlite3_uri_key()], 4142 ** <li> [sqlite3_filename_database()], 4143 ** <li> [sqlite3_filename_journal()], or 4144 ** <li> [sqlite3_filename_wal()]. 4145 ** </ul> 4146 ** If a memory allocation error occurs, sqlite3_create_filename() might 4147 ** return a NULL pointer. The memory obtained from sqlite3_create_filename(X) 4148 ** must be released by a corresponding call to sqlite3_free_filename(Y). 4149 ** 4150 ** The P parameter in sqlite3_create_filename(D,J,W,N,P) should be an array 4151 ** of 2*N pointers to strings. Each pair of pointers in this array corresponds 4152 ** to a key and value for a query parameter. The P parameter may be a NULL 4153 ** pointer if N is zero. None of the 2*N pointers in the P array may be 4154 ** NULL pointers and key pointers should not be empty strings. 4155 ** None of the D, J, or W parameters to sqlite3_create_filename(D,J,W,N,P) may 4156 ** be NULL pointers, though they can be empty strings. 4157 ** 4158 ** The sqlite3_free_filename(Y) routine releases a memory allocation 4159 ** previously obtained from sqlite3_create_filename(). Invoking 4160 ** sqlite3_free_filename(Y) where Y is a NULL pointer is a harmless no-op. 4161 ** 4162 ** If the Y parameter to sqlite3_free_filename(Y) is anything other 4163 ** than a NULL pointer or a pointer previously acquired from 4164 ** sqlite3_create_filename(), then bad things such as heap 4165 ** corruption or segfaults may occur. The value Y should not be 4166 ** used again after sqlite3_free_filename(Y) has been called. This means 4167 ** that if the [sqlite3_vfs.xOpen()] method of a VFS has been called using Y, 4168 ** then the corresponding [sqlite3_module.xClose() method should also be 4169 ** invoked prior to calling sqlite3_free_filename(Y). 4170 */ 4171 SQLITE_API sqlite3_filename sqlite3_create_filename( 4172 const char *zDatabase, 4173 const char *zJournal, 4174 const char *zWal, 4175 int nParam, 4176 const char **azParam 4177 ); 4178 SQLITE_API void sqlite3_free_filename(sqlite3_filename); 4179 4180 /* 4181 ** CAPI3REF: Error Codes And Messages 4182 ** METHOD: sqlite3 4183 ** 4184 ** ^If the most recent sqlite3_* API call associated with 4185 ** [database connection] D failed, then the sqlite3_errcode(D) interface 4186 ** returns the numeric [result code] or [extended result code] for that 4187 ** API call. 4188 ** ^The sqlite3_extended_errcode() 4189 ** interface is the same except that it always returns the 4190 ** [extended result code] even when extended result codes are 4191 ** disabled. 4192 ** 4193 ** The values returned by sqlite3_errcode() and/or 4194 ** sqlite3_extended_errcode() might change with each API call. 4195 ** Except, there are some interfaces that are guaranteed to never 4196 ** change the value of the error code. The error-code preserving 4197 ** interfaces include the following: 4198 ** 4199 ** <ul> 4200 ** <li> sqlite3_errcode() 4201 ** <li> sqlite3_extended_errcode() 4202 ** <li> sqlite3_errmsg() 4203 ** <li> sqlite3_errmsg16() 4204 ** <li> sqlite3_error_offset() 4205 ** <li> sqlite3_db_handle() 4206 ** </ul> 4207 ** 4208 ** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language 4209 ** text that describes the error, as either UTF-8 or UTF-16 respectively, 4210 ** or NULL if no error message is available. 4211 ** (See how SQLite handles [invalid UTF] for exceptions to this rule.) 4212 ** ^(Memory to hold the error message string is managed internally. 4213 ** The application does not need to worry about freeing the result. 4214 ** However, the error string might be overwritten or deallocated by 4215 ** subsequent calls to other SQLite interface functions.)^ 4216 ** 4217 ** ^The sqlite3_errstr(E) interface returns the English-language text 4218 ** that describes the [result code] E, as UTF-8, or NULL if E is not a 4219 ** result code for which a text error message is available. 4220 ** ^(Memory to hold the error message string is managed internally 4221 ** and must not be freed by the application)^. 4222 ** 4223 ** ^If the most recent error references a specific token in the input 4224 ** SQL, the sqlite3_error_offset() interface returns the byte offset 4225 ** of the start of that token. ^The byte offset returned by 4226 ** sqlite3_error_offset() assumes that the input SQL is UTF-8. 4227 ** ^If the most recent error does not reference a specific token in the input 4228 ** SQL, then the sqlite3_error_offset() function returns -1. 4229 ** 4230 ** When the serialized [threading mode] is in use, it might be the 4231 ** case that a second error occurs on a separate thread in between 4232 ** the time of the first error and the call to these interfaces. 4233 ** When that happens, the second error will be reported since these 4234 ** interfaces always report the most recent result. To avoid 4235 ** this, each thread can obtain exclusive use of the [database connection] D 4236 ** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning 4237 ** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after 4238 ** all calls to the interfaces listed here are completed. 4239 ** 4240 ** If an interface fails with SQLITE_MISUSE, that means the interface 4241 ** was invoked incorrectly by the application. In that case, the 4242 ** error code and message may or may not be set. 4243 */ 4244 SQLITE_API int sqlite3_errcode(sqlite3 *db); 4245 SQLITE_API int sqlite3_extended_errcode(sqlite3 *db); 4246 SQLITE_API const char *sqlite3_errmsg(sqlite3*); 4247 SQLITE_API const void *sqlite3_errmsg16(sqlite3*); 4248 SQLITE_API const char *sqlite3_errstr(int); 4249 SQLITE_API int sqlite3_error_offset(sqlite3 *db); 4250 4251 /* 4252 ** CAPI3REF: Set Error Code And Message 4253 ** METHOD: sqlite3 4254 ** 4255 ** Set the error code of the database handle passed as the first argument 4256 ** to errcode, and the error message to a copy of nul-terminated string 4257 ** zErrMsg. If zErrMsg is passed NULL, then the error message is set to 4258 ** the default message associated with the supplied error code. Subsequent 4259 ** calls to [sqlite3_errcode()] and [sqlite3_errmsg()] and similar will 4260 ** return the values set by this routine in place of what was previously 4261 ** set by SQLite itself. 4262 ** 4263 ** This function returns SQLITE_OK if the error code and error message are 4264 ** successfully set, SQLITE_NOMEM if an OOM occurs, and SQLITE_MISUSE if 4265 ** the database handle is NULL or invalid. 4266 ** 4267 ** The error code and message set by this routine remains in effect until 4268 ** they are changed, either by another call to this routine or until they are 4269 ** changed to by SQLite itself to reflect the result of some subsquent 4270 ** API call. 4271 ** 4272 ** This function is intended for use by SQLite extensions or wrappers. The 4273 ** idea is that an extension or wrapper can use this routine to set error 4274 ** messages and error codes and thus behave more like a core SQLite 4275 ** feature from the point of view of an application. 4276 */ 4277 SQLITE_API int sqlite3_set_errmsg(sqlite3 *db, int errcode, const char *zErrMsg); 4278 4279 /* 4280 ** CAPI3REF: Prepared Statement Object 4281 ** KEYWORDS: {prepared statement} {prepared statements} 4282 ** 4283 ** An instance of this object represents a single SQL statement that 4284 ** has been compiled into binary form and is ready to be evaluated. 4285 ** 4286 ** Think of each SQL statement as a separate computer program. The 4287 ** original SQL text is source code. A prepared statement object 4288 ** is the compiled object code. All SQL must be converted into a 4289 ** prepared statement before it can be run. 4290 ** 4291 ** The life-cycle of a prepared statement object usually goes like this: 4292 ** 4293 ** <ol> 4294 ** <li> Create the prepared statement object using [sqlite3_prepare_v2()]. 4295 ** <li> Bind values to [parameters] using the sqlite3_bind_*() 4296 ** interfaces. 4297 ** <li> Run the SQL by calling [sqlite3_step()] one or more times. 4298 ** <li> Reset the prepared statement using [sqlite3_reset()] then go back 4299 ** to step 2. Do this zero or more times. 4300 ** <li> Destroy the object using [sqlite3_finalize()]. 4301 ** </ol> 4302 */ 4303 typedef struct sqlite3_stmt sqlite3_stmt; 4304 4305 /* 4306 ** CAPI3REF: Run-time Limits 4307 ** METHOD: sqlite3 4308 ** 4309 ** ^(This interface allows the size of various constructs to be limited 4310 ** on a connection by connection basis. The first parameter is the 4311 ** [database connection] whose limit is to be set or queried. The 4312 ** second parameter is one of the [limit categories] that define a 4313 ** class of constructs to be size limited. The third parameter is the 4314 ** new limit for that construct.)^ 4315 ** 4316 ** ^If the new limit is a negative number, the limit is unchanged. 4317 ** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a 4318 ** [limits | hard upper bound] 4319 ** set at compile-time by a C preprocessor macro called 4320 ** [limits | SQLITE_MAX_<i>NAME</i>]. 4321 ** (The "_LIMIT_" in the name is changed to "_MAX_".))^ 4322 ** ^Attempts to increase a limit above its hard upper bound are 4323 ** silently truncated to the hard upper bound. 4324 ** 4325 ** ^Regardless of whether or not the limit was changed, the 4326 ** [sqlite3_limit()] interface returns the prior value of the limit. 4327 ** ^Hence, to find the current value of a limit without changing it, 4328 ** simply invoke this interface with the third parameter set to -1. 4329 ** 4330 ** Run-time limits are intended for use in applications that manage 4331 ** both their own internal database and also databases that are controlled 4332 ** by untrusted external sources. An example application might be a 4333 ** web browser that has its own databases for storing history and 4334 ** separate databases controlled by JavaScript applications downloaded 4335 ** off the Internet. The internal databases can be given the 4336 ** large, default limits. Databases managed by external sources can 4337 ** be given much smaller limits designed to prevent a denial of service 4338 ** attack. Developers might also want to use the [sqlite3_set_authorizer()] 4339 ** interface to further control untrusted SQL. The size of the database 4340 ** created by an untrusted script can be contained using the 4341 ** [max_page_count] [PRAGMA]. 4342 ** 4343 ** New run-time limit categories may be added in future releases. 4344 */ 4345 SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal); 4346 4347 /* 4348 ** CAPI3REF: Run-Time Limit Categories 4349 ** KEYWORDS: {limit category} {*limit categories} 4350 ** 4351 ** These constants define various performance limits 4352 ** that can be lowered at run-time using [sqlite3_limit()]. 4353 ** A concise description of these limits follows, and additional information 4354 ** is available at [limits | Limits in SQLite]. 4355 ** 4356 ** <dl> 4357 ** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt> 4358 ** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^ 4359 ** 4360 ** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt> 4361 ** <dd>The maximum length of an SQL statement, in bytes.</dd>)^ 4362 ** 4363 ** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt> 4364 ** <dd>The maximum number of columns in a table definition or in the 4365 ** result set of a [SELECT] or the maximum number of columns in an index 4366 ** or in an ORDER BY or GROUP BY clause.</dd>)^ 4367 ** 4368 ** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt> 4369 ** <dd>The maximum depth of the parse tree on any expression and 4370 ** the maximum nesting depth for subqueries and VIEWs</dd>)^ 4371 ** 4372 ** [[SQLITE_LIMIT_PARSER_DEPTH]] ^(<dt>SQLITE_LIMIT_PARSER_DEPTH</dt> 4373 ** <dd>The maximum depth of the LALR(1) parser stack used to analyze 4374 ** input SQL statements.</dd>)^ 4375 ** 4376 ** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt> 4377 ** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^ 4378 ** 4379 ** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt> 4380 ** <dd>The maximum number of instructions in a virtual machine program 4381 ** used to implement an SQL statement. If [sqlite3_prepare_v2()] or 4382 ** the equivalent tries to allocate space for more than this many opcodes 4383 ** in a single prepared statement, an SQLITE_NOMEM error is returned.</dd>)^ 4384 ** 4385 ** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt> 4386 ** <dd>The maximum number of arguments on a function.</dd>)^ 4387 ** 4388 ** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt> 4389 ** <dd>The maximum number of [ATTACH | attached databases].)^</dd> 4390 ** 4391 ** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]] 4392 ** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt> 4393 ** <dd>The maximum length of the pattern argument to the [LIKE] or 4394 ** [GLOB] operators.</dd>)^ 4395 ** 4396 ** [[SQLITE_LIMIT_VARIABLE_NUMBER]] 4397 ** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt> 4398 ** <dd>The maximum index number of any [parameter] in an SQL statement.)^ 4399 ** 4400 ** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt> 4401 ** <dd>The maximum depth of recursion for triggers, and the maximum 4402 ** nesting depth for separate triggers.</dd>)^ 4403 ** 4404 ** [[SQLITE_LIMIT_WORKER_THREADS]] ^(<dt>SQLITE_LIMIT_WORKER_THREADS</dt> 4405 ** <dd>The maximum number of auxiliary worker threads that a single 4406 ** [prepared statement] may start.</dd>)^ 4407 ** </dl> 4408 */ 4409 #define SQLITE_LIMIT_LENGTH 0 4410 #define SQLITE_LIMIT_SQL_LENGTH 1 4411 #define SQLITE_LIMIT_COLUMN 2 4412 #define SQLITE_LIMIT_EXPR_DEPTH 3 4413 #define SQLITE_LIMIT_COMPOUND_SELECT 4 4414 #define SQLITE_LIMIT_VDBE_OP 5 4415 #define SQLITE_LIMIT_FUNCTION_ARG 6 4416 #define SQLITE_LIMIT_ATTACHED 7 4417 #define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8 4418 #define SQLITE_LIMIT_VARIABLE_NUMBER 9 4419 #define SQLITE_LIMIT_TRIGGER_DEPTH 10 4420 #define SQLITE_LIMIT_WORKER_THREADS 11 4421 #define SQLITE_LIMIT_PARSER_DEPTH 12 4422 4423 /* 4424 ** CAPI3REF: Prepare Flags 4425 ** 4426 ** These constants define various flags that can be passed into the 4427 ** "prepFlags" parameter of the [sqlite3_prepare_v3()] and 4428 ** [sqlite3_prepare16_v3()] interfaces. 4429 ** 4430 ** New flags may be added in future releases of SQLite. 4431 ** 4432 ** <dl> 4433 ** [[SQLITE_PREPARE_PERSISTENT]] ^(<dt>SQLITE_PREPARE_PERSISTENT</dt> 4434 ** <dd>The SQLITE_PREPARE_PERSISTENT flag is a hint to the query planner 4435 ** that the prepared statement will be retained for a long time and 4436 ** probably reused many times.)^ ^Without this flag, [sqlite3_prepare_v3()] 4437 ** and [sqlite3_prepare16_v3()] assume that the prepared statement will 4438 ** be used just once or at most a few times and then destroyed using 4439 ** [sqlite3_finalize()] relatively soon. The current implementation acts 4440 ** on this hint by avoiding the use of [lookaside memory] so as not to 4441 ** deplete the limited store of lookaside memory. Future versions of 4442 ** SQLite may act on this hint differently. 4443 ** 4444 ** [[SQLITE_PREPARE_NORMALIZE]] <dt>SQLITE_PREPARE_NORMALIZE</dt> 4445 ** <dd>The SQLITE_PREPARE_NORMALIZE flag is a no-op. This flag used 4446 ** to be required for any prepared statement that wanted to use the 4447 ** [sqlite3_normalized_sql()] interface. However, the 4448 ** [sqlite3_normalized_sql()] interface is now available to all 4449 ** prepared statements, regardless of whether or not they use this 4450 ** flag. 4451 ** 4452 ** [[SQLITE_PREPARE_NO_VTAB]] <dt>SQLITE_PREPARE_NO_VTAB</dt> 4453 ** <dd>The SQLITE_PREPARE_NO_VTAB flag causes the SQL compiler 4454 ** to return an error (error code SQLITE_ERROR) if the statement uses 4455 ** any virtual tables. 4456 ** 4457 ** [[SQLITE_PREPARE_DONT_LOG]] <dt>SQLITE_PREPARE_DONT_LOG</dt> 4458 ** <dd>The SQLITE_PREPARE_DONT_LOG flag prevents SQL compiler 4459 ** errors from being sent to the error log defined by 4460 ** [SQLITE_CONFIG_LOG]. This can be used, for example, to do test 4461 ** compiles to see if some SQL syntax is well-formed, without generating 4462 ** messages on the global error log when it is not. If the test compile 4463 ** fails, the sqlite3_prepare_v3() call returns the same error indications 4464 ** with or without this flag; it just omits the call to [sqlite3_log()] that 4465 ** logs the error. 4466 ** 4467 ** [[SQLITE_PREPARE_FROM_DDL]] <dt>SQLITE_PREPARE_FROM_DDL</dt> 4468 ** <dd>The SQLITE_PREPARE_FROM_DDL flag causes the SQL compiler to enforce 4469 ** security constraints that would otherwise only be enforced when parsing 4470 ** the database schema. In other words, the SQLITE_PREPARE_FROM_DDL flag 4471 ** causes the SQL compiler to treat the SQL statement being prepared as if 4472 ** it had come from an attacker. When SQLITE_PREPARE_FROM_DDL is used and 4473 ** [SQLITE_DBCONFIG_TRUSTED_SCHEMA] is off, SQL functions may only be called 4474 ** if they are tagged with [SQLITE_INNOCUOUS] and virtual tables may only 4475 ** be used if they are tagged with [SQLITE_VTAB_INNOCUOUS]. Best practice 4476 ** is to use the SQLITE_PREPARE_FROM_DDL option when preparing any SQL that 4477 ** is derived from parts of the database schema. In particular, virtual 4478 ** table implementations that run SQL statements that are derived from 4479 ** arguments to their CREATE VIRTUAL TABLE statement should always use 4480 ** [sqlite3_prepare_v3()] and set the SQLITE_PREPARE_FROM_DDL flag to 4481 ** prevent bypass of the [SQLITE_DBCONFIG_TRUSTED_SCHEMA] security checks. 4482 ** </dl> 4483 */ 4484 #define SQLITE_PREPARE_PERSISTENT 0x01 4485 #define SQLITE_PREPARE_NORMALIZE 0x02 4486 #define SQLITE_PREPARE_NO_VTAB 0x04 4487 #define SQLITE_PREPARE_DONT_LOG 0x10 4488 #define SQLITE_PREPARE_FROM_DDL 0x20 4489 4490 /* 4491 ** CAPI3REF: Compiling An SQL Statement 4492 ** KEYWORDS: {SQL statement compiler} 4493 ** METHOD: sqlite3 4494 ** CONSTRUCTOR: sqlite3_stmt 4495 ** 4496 ** To execute an SQL statement, it must first be compiled into a byte-code 4497 ** program using one of these routines. Or, in other words, these routines 4498 ** are constructors for the [prepared statement] object. 4499 ** 4500 ** The preferred routine to use is [sqlite3_prepare_v2()]. The 4501 ** [sqlite3_prepare()] interface is legacy and should be avoided. 4502 ** [sqlite3_prepare_v3()] has an extra 4503 ** [SQLITE_PREPARE_FROM_DDL|"prepFlags" option] that is sometimes 4504 ** needed for special purpose or to pass along security restrictions. 4505 ** 4506 ** The use of the UTF-8 interfaces is preferred, as SQLite currently 4507 ** does all parsing using UTF-8. The UTF-16 interfaces are provided 4508 ** as a convenience. The UTF-16 interfaces work by converting the 4509 ** input text into UTF-8, then invoking the corresponding UTF-8 interface. 4510 ** 4511 ** The first argument, "db", is a [database connection] obtained from a 4512 ** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or 4513 ** [sqlite3_open16()]. The database connection must not have been closed. 4514 ** 4515 ** The second argument, "zSql", is the statement to be compiled, encoded 4516 ** as either UTF-8 or UTF-16. The sqlite3_prepare(), sqlite3_prepare_v2(), 4517 ** and sqlite3_prepare_v3() 4518 ** interfaces use UTF-8, and sqlite3_prepare16(), sqlite3_prepare16_v2(), 4519 ** and sqlite3_prepare16_v3() use UTF-16. 4520 ** 4521 ** ^If the nByte argument is negative, then zSql is read up to the 4522 ** first zero terminator. ^If nByte is positive, then it is the maximum 4523 ** number of bytes read from zSql. When nByte is positive, zSql is read 4524 ** up to the first zero terminator or until the nByte bytes have been read, 4525 ** whichever comes first. ^If nByte is zero, then no prepared 4526 ** statement is generated. 4527 ** If the caller knows that the supplied string is nul-terminated, then 4528 ** there is a small performance advantage to passing an nByte parameter that 4529 ** is the number of bytes in the input string <i>including</i> 4530 ** the nul-terminator. 4531 ** Note that nByte measures the length of the input in bytes, not 4532 ** characters, even for the UTF-16 interfaces. 4533 ** 4534 ** ^If pzTail is not NULL then *pzTail is made to point to the first byte 4535 ** past the end of the first SQL statement in zSql. These routines only 4536 ** compile the first statement in zSql, so *pzTail is left pointing to 4537 ** what remains uncompiled. 4538 ** 4539 ** ^*ppStmt is left pointing to a compiled [prepared statement] that can be 4540 ** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set 4541 ** to NULL. ^If the input text contains no SQL (if the input is an empty 4542 ** string or a comment) then *ppStmt is set to NULL. 4543 ** The calling procedure is responsible for deleting the compiled 4544 ** SQL statement using [sqlite3_finalize()] after it has finished with it. 4545 ** ppStmt may not be NULL. 4546 ** 4547 ** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK]; 4548 ** otherwise an [error code] is returned. 4549 ** 4550 ** The sqlite3_prepare_v2(), sqlite3_prepare_v3(), sqlite3_prepare16_v2(), 4551 ** and sqlite3_prepare16_v3() interfaces are recommended for all new programs. 4552 ** The older interfaces (sqlite3_prepare() and sqlite3_prepare16()) 4553 ** are retained for backwards compatibility, but their use is discouraged. 4554 ** ^In the "vX" interfaces, the prepared statement 4555 ** that is returned (the [sqlite3_stmt] object) contains a copy of the 4556 ** original SQL text. This causes the [sqlite3_step()] interface to 4557 ** behave differently in three ways: 4558 ** 4559 ** <ol> 4560 ** <li> 4561 ** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it 4562 ** always used to do, [sqlite3_step()] will automatically recompile the SQL 4563 ** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY] 4564 ** retries will occur before sqlite3_step() gives up and returns an error. 4565 ** </li> 4566 ** 4567 ** <li> 4568 ** ^When an error occurs, [sqlite3_step()] will return one of the detailed 4569 ** [error codes] or [extended error codes]. ^The legacy behavior was that 4570 ** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code 4571 ** and the application would have to make a second call to [sqlite3_reset()] 4572 ** in order to find the underlying cause of the problem. With the "v2" prepare 4573 ** interfaces, the underlying reason for the error is returned immediately. 4574 ** </li> 4575 ** 4576 ** <li> 4577 ** ^If the specific value bound to a [parameter | host parameter] in the 4578 ** WHERE clause might influence the choice of query plan for a statement, 4579 ** then the statement will be automatically recompiled, as if there had been 4580 ** a schema change, on the first [sqlite3_step()] call following any change 4581 ** to the [sqlite3_bind_text | bindings] of that [parameter]. 4582 ** ^The specific value of a WHERE-clause [parameter] might influence the 4583 ** choice of query plan if the parameter is the left-hand side of a [LIKE] 4584 ** or [GLOB] operator or if the parameter is compared to an indexed column 4585 ** and the [SQLITE_ENABLE_STAT4] compile-time option is enabled. 4586 ** </li> 4587 ** </ol> 4588 ** 4589 ** <p>^sqlite3_prepare_v3() differs from sqlite3_prepare_v2() only in having 4590 ** the extra prepFlags parameter, which is a bit array consisting of zero or 4591 ** more of the [SQLITE_PREPARE_PERSISTENT|SQLITE_PREPARE_*] flags. ^The 4592 ** sqlite3_prepare_v2() interface works exactly the same as 4593 ** sqlite3_prepare_v3() with a zero prepFlags parameter. 4594 */ 4595 SQLITE_API int sqlite3_prepare( 4596 sqlite3 *db, /* Database handle */ 4597 const char *zSql, /* SQL statement, UTF-8 encoded */ 4598 int nByte, /* Maximum length of zSql in bytes. */ 4599 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4600 const char **pzTail /* OUT: Pointer to unused portion of zSql */ 4601 ); 4602 SQLITE_API int sqlite3_prepare_v2( 4603 sqlite3 *db, /* Database handle */ 4604 const char *zSql, /* SQL statement, UTF-8 encoded */ 4605 int nByte, /* Maximum length of zSql in bytes. */ 4606 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4607 const char **pzTail /* OUT: Pointer to unused portion of zSql */ 4608 ); 4609 SQLITE_API int sqlite3_prepare_v3( 4610 sqlite3 *db, /* Database handle */ 4611 const char *zSql, /* SQL statement, UTF-8 encoded */ 4612 int nByte, /* Maximum length of zSql in bytes. */ 4613 unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */ 4614 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4615 const char **pzTail /* OUT: Pointer to unused portion of zSql */ 4616 ); 4617 SQLITE_API int sqlite3_prepare16( 4618 sqlite3 *db, /* Database handle */ 4619 const void *zSql, /* SQL statement, UTF-16 encoded */ 4620 int nByte, /* Maximum length of zSql in bytes. */ 4621 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4622 const void **pzTail /* OUT: Pointer to unused portion of zSql */ 4623 ); 4624 SQLITE_API int sqlite3_prepare16_v2( 4625 sqlite3 *db, /* Database handle */ 4626 const void *zSql, /* SQL statement, UTF-16 encoded */ 4627 int nByte, /* Maximum length of zSql in bytes. */ 4628 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4629 const void **pzTail /* OUT: Pointer to unused portion of zSql */ 4630 ); 4631 SQLITE_API int sqlite3_prepare16_v3( 4632 sqlite3 *db, /* Database handle */ 4633 const void *zSql, /* SQL statement, UTF-16 encoded */ 4634 int nByte, /* Maximum length of zSql in bytes. */ 4635 unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */ 4636 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4637 const void **pzTail /* OUT: Pointer to unused portion of zSql */ 4638 ); 4639 4640 /* 4641 ** CAPI3REF: Retrieving Statement SQL 4642 ** METHOD: sqlite3_stmt 4643 ** 4644 ** ^The sqlite3_sql(P) interface returns a pointer to a copy of the UTF-8 4645 ** SQL text used to create [prepared statement] P if P was 4646 ** created by [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], 4647 ** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()]. 4648 ** ^The sqlite3_expanded_sql(P) interface returns a pointer to a UTF-8 4649 ** string containing the SQL text of prepared statement P with 4650 ** [bound parameters] expanded. 4651 ** ^The sqlite3_normalized_sql(P) interface returns a pointer to a UTF-8 4652 ** string containing the normalized SQL text of prepared statement P. The 4653 ** semantics used to normalize a SQL statement are unspecified and subject 4654 ** to change. At a minimum, literal values will be replaced with suitable 4655 ** placeholders. 4656 ** 4657 ** ^(For example, if a prepared statement is created using the SQL 4658 ** text "SELECT $abc,:xyz" and if parameter $abc is bound to integer 2345 4659 ** and parameter :xyz is unbound, then sqlite3_sql() will return 4660 ** the original string, "SELECT $abc,:xyz" but sqlite3_expanded_sql() 4661 ** will return "SELECT 2345,NULL".)^ 4662 ** 4663 ** ^The sqlite3_expanded_sql() interface returns NULL if insufficient memory 4664 ** is available to hold the result, or if the result would exceed the 4665 ** maximum string length determined by the [SQLITE_LIMIT_LENGTH]. 4666 ** 4667 ** ^The [SQLITE_TRACE_SIZE_LIMIT] compile-time option limits the size of 4668 ** bound parameter expansions. ^The [SQLITE_OMIT_TRACE] compile-time 4669 ** option causes sqlite3_expanded_sql() to always return NULL. 4670 ** 4671 ** ^The strings returned by sqlite3_sql(P) and sqlite3_normalized_sql(P) 4672 ** are managed by SQLite and are automatically freed when the prepared 4673 ** statement is finalized. 4674 ** ^The string returned by sqlite3_expanded_sql(P), on the other hand, 4675 ** is obtained from [sqlite3_malloc()] and must be freed by the application 4676 ** by passing it to [sqlite3_free()]. 4677 ** 4678 ** ^The sqlite3_normalized_sql() interface is only available if 4679 ** the [SQLITE_ENABLE_NORMALIZE] compile-time option is defined. 4680 */ 4681 SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt); 4682 SQLITE_API char *sqlite3_expanded_sql(sqlite3_stmt *pStmt); 4683 #ifdef SQLITE_ENABLE_NORMALIZE 4684 SQLITE_API const char *sqlite3_normalized_sql(sqlite3_stmt *pStmt); 4685 #endif 4686 4687 /* 4688 ** CAPI3REF: Determine If An SQL Statement Writes The Database 4689 ** METHOD: sqlite3_stmt 4690 ** 4691 ** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if 4692 ** and only if the [prepared statement] X makes no direct changes to 4693 ** the content of the database file. 4694 ** 4695 ** Note that [application-defined SQL functions] or 4696 ** [virtual tables] might change the database indirectly as a side effect. 4697 ** ^(For example, if an application defines a function "eval()" that 4698 ** calls [sqlite3_exec()], then the following SQL statement would 4699 ** change the database file through side-effects: 4700 ** 4701 ** <blockquote><pre> 4702 ** SELECT eval('DELETE FROM t1') FROM t2; 4703 ** </pre></blockquote> 4704 ** 4705 ** But because the [SELECT] statement does not change the database file 4706 ** directly, sqlite3_stmt_readonly() would still return true.)^ 4707 ** 4708 ** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK], 4709 ** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true, 4710 ** since the statements themselves do not actually modify the database but 4711 ** rather they control the timing of when other statements modify the 4712 ** database. ^The [ATTACH] and [DETACH] statements also cause 4713 ** sqlite3_stmt_readonly() to return true since, while those statements 4714 ** change the configuration of a database connection, they do not make 4715 ** changes to the content of the database files on disk. 4716 ** ^The sqlite3_stmt_readonly() interface returns true for [BEGIN] since 4717 ** [BEGIN] merely sets internal flags, but the [BEGIN|BEGIN IMMEDIATE] and 4718 ** [BEGIN|BEGIN EXCLUSIVE] commands do touch the database and so 4719 ** sqlite3_stmt_readonly() returns false for those commands. 4720 ** 4721 ** ^This routine returns false if there is any possibility that the 4722 ** statement might change the database file. ^A false return does 4723 ** not guarantee that the statement will change the database file. 4724 ** ^For example, an UPDATE statement might have a WHERE clause that 4725 ** makes it a no-op, but the sqlite3_stmt_readonly() result would still 4726 ** be false. ^Similarly, a CREATE TABLE IF NOT EXISTS statement is a 4727 ** read-only no-op if the table already exists, but 4728 ** sqlite3_stmt_readonly() still returns false for such a statement. 4729 ** 4730 ** ^If prepared statement X is an [EXPLAIN] or [EXPLAIN QUERY PLAN] 4731 ** statement, then sqlite3_stmt_readonly(X) returns the same value as 4732 ** if the EXPLAIN or EXPLAIN QUERY PLAN prefix were omitted. 4733 */ 4734 SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt); 4735 4736 /* 4737 ** CAPI3REF: Query The EXPLAIN Setting For A Prepared Statement 4738 ** METHOD: sqlite3_stmt 4739 ** 4740 ** ^The sqlite3_stmt_isexplain(S) interface returns 1 if the 4741 ** prepared statement S is an EXPLAIN statement, or 2 if the 4742 ** statement S is an EXPLAIN QUERY PLAN. 4743 ** ^The sqlite3_stmt_isexplain(S) interface returns 0 if S is 4744 ** an ordinary statement or a NULL pointer. 4745 */ 4746 SQLITE_API int sqlite3_stmt_isexplain(sqlite3_stmt *pStmt); 4747 4748 /* 4749 ** CAPI3REF: Change The EXPLAIN Setting For A Prepared Statement 4750 ** METHOD: sqlite3_stmt 4751 ** 4752 ** The sqlite3_stmt_explain(S,E) interface changes the EXPLAIN 4753 ** setting for [prepared statement] S. If E is zero, then S becomes 4754 ** a normal prepared statement. If E is 1, then S behaves as if 4755 ** its SQL text began with "[EXPLAIN]". If E is 2, then S behaves as if 4756 ** its SQL text began with "[EXPLAIN QUERY PLAN]". 4757 ** 4758 ** Calling sqlite3_stmt_explain(S,E) might cause S to be reprepared. 4759 ** SQLite tries to avoid a reprepare, but a reprepare might be necessary 4760 ** on the first transition into EXPLAIN or EXPLAIN QUERY PLAN mode. 4761 ** 4762 ** Because of the potential need to reprepare, a call to 4763 ** sqlite3_stmt_explain(S,E) will fail with SQLITE_ERROR if S cannot be 4764 ** reprepared because it was created using [sqlite3_prepare()] instead of 4765 ** the newer [sqlite3_prepare_v2()] or [sqlite3_prepare_v3()] interfaces and 4766 ** hence has no saved SQL text with which to reprepare. 4767 ** 4768 ** Changing the explain setting for a prepared statement does not change 4769 ** the original SQL text for the statement. Hence, if the SQL text originally 4770 ** began with EXPLAIN or EXPLAIN QUERY PLAN, but sqlite3_stmt_explain(S,0) 4771 ** is called to convert the statement into an ordinary statement, the EXPLAIN 4772 ** or EXPLAIN QUERY PLAN keywords will still appear in the sqlite3_sql(S) 4773 ** output, even though the statement now acts like a normal SQL statement. 4774 ** 4775 ** This routine returns SQLITE_OK if the explain mode is successfully 4776 ** changed, or an error code if the explain mode could not be changed. 4777 ** The explain mode cannot be changed while a statement is active. 4778 ** Hence, it is good practice to call [sqlite3_reset(S)] 4779 ** immediately prior to calling sqlite3_stmt_explain(S,E). 4780 */ 4781 SQLITE_API int sqlite3_stmt_explain(sqlite3_stmt *pStmt, int eMode); 4782 4783 /* 4784 ** CAPI3REF: Determine If A Prepared Statement Has Been Reset 4785 ** METHOD: sqlite3_stmt 4786 ** 4787 ** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the 4788 ** [prepared statement] S has been stepped at least once using 4789 ** [sqlite3_step(S)] but has neither run to completion (returned 4790 ** [SQLITE_DONE] from [sqlite3_step(S)]) nor 4791 ** been reset using [sqlite3_reset(S)]. ^The sqlite3_stmt_busy(S) 4792 ** interface returns false if S is a NULL pointer. If S is not a 4793 ** NULL pointer and is not a pointer to a valid [prepared statement] 4794 ** object, then the behavior is undefined and probably undesirable. 4795 ** 4796 ** This interface can be used in combination [sqlite3_next_stmt()] 4797 ** to locate all prepared statements associated with a database 4798 ** connection that are in need of being reset. This can be used, 4799 ** for example, in diagnostic routines to search for prepared 4800 ** statements that are holding a transaction open. 4801 */ 4802 SQLITE_API int sqlite3_stmt_busy(sqlite3_stmt*); 4803 4804 /* 4805 ** CAPI3REF: Dynamically Typed Value Object 4806 ** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value} 4807 ** 4808 ** SQLite uses the sqlite3_value object to represent all values 4809 ** that can be stored in a database table. SQLite uses dynamic typing 4810 ** for the values it stores. ^Values stored in sqlite3_value objects 4811 ** can be integers, floating point values, strings, BLOBs, or NULL. 4812 ** 4813 ** An sqlite3_value object may be either "protected" or "unprotected". 4814 ** Some interfaces require a protected sqlite3_value. Other interfaces 4815 ** will accept either a protected or an unprotected sqlite3_value. 4816 ** Every interface that accepts sqlite3_value arguments specifies 4817 ** whether or not it requires a protected sqlite3_value. The 4818 ** [sqlite3_value_dup()] interface can be used to construct a new 4819 ** protected sqlite3_value from an unprotected sqlite3_value. 4820 ** 4821 ** The terms "protected" and "unprotected" refer to whether or not 4822 ** a mutex is held. An internal mutex is held for a protected 4823 ** sqlite3_value object but no mutex is held for an unprotected 4824 ** sqlite3_value object. If SQLite is compiled to be single-threaded 4825 ** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0) 4826 ** or if SQLite is run in one of reduced mutex modes 4827 ** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD] 4828 ** then there is no distinction between protected and unprotected 4829 ** sqlite3_value objects and they can be used interchangeably. However, 4830 ** for maximum code portability it is recommended that applications 4831 ** still make the distinction between protected and unprotected 4832 ** sqlite3_value objects even when not strictly required. 4833 ** 4834 ** ^The sqlite3_value objects that are passed as parameters into the 4835 ** implementation of [application-defined SQL functions] are protected. 4836 ** ^The sqlite3_value objects returned by [sqlite3_vtab_rhs_value()] 4837 ** are protected. 4838 ** ^The sqlite3_value object returned by 4839 ** [sqlite3_column_value()] is unprotected. 4840 ** Unprotected sqlite3_value objects may only be used as arguments 4841 ** to [sqlite3_result_value()], [sqlite3_bind_value()], and 4842 ** [sqlite3_value_dup()]. 4843 ** The [sqlite3_value_blob | sqlite3_value_type()] family of 4844 ** interfaces require protected sqlite3_value objects. 4845 */ 4846 typedef struct sqlite3_value sqlite3_value; 4847 4848 /* 4849 ** CAPI3REF: SQL Function Context Object 4850 ** 4851 ** The context in which an SQL function executes is stored in an 4852 ** sqlite3_context object. ^A pointer to an sqlite3_context object 4853 ** is always the first parameter to [application-defined SQL functions]. 4854 ** The application-defined SQL function implementation will pass this 4855 ** pointer through into calls to [sqlite3_result_int | sqlite3_result()], 4856 ** [sqlite3_aggregate_context()], [sqlite3_user_data()], 4857 ** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()], 4858 ** and/or [sqlite3_set_auxdata()]. 4859 */ 4860 typedef struct sqlite3_context sqlite3_context; 4861 4862 /* 4863 ** CAPI3REF: Binding Values To Prepared Statements 4864 ** KEYWORDS: {host parameter} {host parameters} {host parameter name} 4865 ** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding} 4866 ** METHOD: sqlite3_stmt 4867 ** 4868 ** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants, 4869 ** literals may be replaced by a [parameter] that matches one of the following 4870 ** templates: 4871 ** 4872 ** <ul> 4873 ** <li> ? 4874 ** <li> ?NNN 4875 ** <li> :VVV 4876 ** <li> @VVV 4877 ** <li> $VVV 4878 ** </ul> 4879 ** 4880 ** In the templates above, NNN represents an integer literal, 4881 ** and VVV represents an alphanumeric identifier.)^ ^The values of these 4882 ** parameters (also called "host parameter names" or "SQL parameters") 4883 ** can be set using the sqlite3_bind_*() routines defined here. 4884 ** 4885 ** ^The first argument to the sqlite3_bind_*() routines is always 4886 ** a pointer to the [sqlite3_stmt] object returned from 4887 ** [sqlite3_prepare_v2()] or its variants. 4888 ** 4889 ** ^The second argument is the index of the SQL parameter to be set. 4890 ** ^The leftmost SQL parameter has an index of 1. ^When the same named 4891 ** SQL parameter is used more than once, second and subsequent 4892 ** occurrences have the same index as the first occurrence. 4893 ** ^The index for named parameters can be looked up using the 4894 ** [sqlite3_bind_parameter_index()] API if desired. ^The index 4895 ** for "?NNN" parameters is the value of NNN. 4896 ** ^The NNN value must be between 1 and the [sqlite3_limit()] 4897 ** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 32766). 4898 ** 4899 ** ^The third argument is the value to bind to the parameter. 4900 ** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16() 4901 ** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter 4902 ** is ignored and the end result is the same as sqlite3_bind_null(). 4903 ** ^If the third parameter to sqlite3_bind_text() is not NULL, then 4904 ** it should be a pointer to well-formed UTF8 text. 4905 ** ^If the third parameter to sqlite3_bind_text16() is not NULL, then 4906 ** it should be a pointer to well-formed UTF16 text. 4907 ** ^If the third parameter to sqlite3_bind_text64() is not NULL, then 4908 ** it should be a pointer to a well-formed unicode string that is 4909 ** either UTF8 if the sixth parameter is SQLITE_UTF8 or SQLITE_UTF8_ZT, 4910 ** or UTF16 otherwise. 4911 ** 4912 ** [[byte-order determination rules]] ^The byte-order of 4913 ** UTF16 input text is determined by the byte-order mark (BOM, U+FEFF) 4914 ** found in the first character, which is removed, or in the absence of a BOM 4915 ** the byte order is the native byte order of the host 4916 ** machine for sqlite3_bind_text16() or the byte order specified in 4917 ** the 6th parameter for sqlite3_bind_text64().)^ 4918 ** ^If UTF16 input text contains invalid unicode 4919 ** characters, then SQLite might change those invalid characters 4920 ** into the unicode replacement character: U+FFFD. 4921 ** 4922 ** ^(In those routines that have a fourth argument, its value is the 4923 ** number of bytes in the parameter. To be clear: the value is the 4924 ** number of <u>bytes</u> in the value, not the number of characters.)^ 4925 ** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16() 4926 ** is negative, then the length of the string is 4927 ** the number of bytes up to the first zero terminator. 4928 ** If the fourth parameter to sqlite3_bind_blob() is negative, then 4929 ** the behavior is undefined. 4930 ** If a non-negative fourth parameter is provided to sqlite3_bind_text() 4931 ** or sqlite3_bind_text16() or sqlite3_bind_text64() then 4932 ** that parameter must be the byte offset 4933 ** where the NUL terminator would occur assuming the string were NUL 4934 ** terminated. If any NUL characters occur at byte offsets less than 4935 ** the value of the fourth parameter then the resulting string value will 4936 ** contain embedded NULs. The result of expressions involving strings 4937 ** with embedded NULs is undefined. 4938 ** 4939 ** ^The fifth argument to the BLOB and string binding interfaces controls 4940 ** or indicates the lifetime of the object referenced by the third parameter. 4941 ** These three options exist: 4942 ** ^ (1) A destructor to dispose of the BLOB or string after SQLite has finished 4943 ** with it may be passed. ^It is called to dispose of the BLOB or string even 4944 ** if the call to the bind API fails, except the destructor is not called if 4945 ** the third parameter is a NULL pointer or the fourth parameter is negative. 4946 ** ^ (2) The special constant, [SQLITE_STATIC], may be passed to indicate that 4947 ** the application remains responsible for disposing of the object. ^In this 4948 ** case, the object and the provided pointer to it must remain valid until 4949 ** either the prepared statement is finalized or the same SQL parameter is 4950 ** bound to something else, whichever occurs sooner. 4951 ** ^ (3) The constant, [SQLITE_TRANSIENT], may be passed to indicate that the 4952 ** object is to be copied prior to the return from sqlite3_bind_*(). ^The 4953 ** object and pointer to it must remain valid until then. ^SQLite will then 4954 ** manage the lifetime of its private copy. 4955 ** 4956 ** ^The sixth argument (the E argument) 4957 ** to sqlite3_bind_text64(S,K,Z,N,D,E) must be one of 4958 ** [SQLITE_UTF8], [SQLITE_UTF8_ZT], [SQLITE_UTF16], [SQLITE_UTF16BE], 4959 ** or [SQLITE_UTF16LE] to specify the encoding of the text in the 4960 ** third parameter, Z. The special value [SQLITE_UTF8_ZT] means that the 4961 ** string argument is both UTF-8 encoded and is zero-terminated. In other 4962 ** words, SQLITE_UTF8_ZT means that the Z array is allocated to hold at 4963 ** least N+1 bytes and that the Z[N] byte is zero. If 4964 ** the E argument to sqlite3_bind_text64(S,K,Z,N,D,E) is not one of the 4965 ** allowed values shown above, or if the text encoding is different 4966 ** from the encoding specified by the sixth parameter, then the behavior 4967 ** is undefined. 4968 ** 4969 ** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that 4970 ** is filled with zeroes. ^A zeroblob uses a fixed amount of memory 4971 ** (just an integer to hold its size) while it is being processed. 4972 ** Zeroblobs are intended to serve as placeholders for BLOBs whose 4973 ** content is later written using 4974 ** [sqlite3_blob_open | incremental BLOB I/O] routines. 4975 ** ^A negative value for the zeroblob results in a zero-length BLOB. 4976 ** 4977 ** ^The sqlite3_bind_pointer(S,I,P,T,D) routine causes the I-th parameter in 4978 ** [prepared statement] S to have an SQL value of NULL, but to also be 4979 ** associated with the pointer P of type T. ^D is either a NULL pointer or 4980 ** a pointer to a destructor function for P. ^SQLite will invoke the 4981 ** destructor D with a single argument of P when it is finished using 4982 ** P, even if the call to sqlite3_bind_pointer() fails. Due to a 4983 ** historical design quirk, results are undefined if D is 4984 ** SQLITE_TRANSIENT. The T parameter should be a static string, 4985 ** preferably a string literal. The sqlite3_bind_pointer() routine is 4986 ** part of the [pointer passing interface] added for SQLite 3.20.0. 4987 ** 4988 ** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer 4989 ** for the [prepared statement] or with a prepared statement for which 4990 ** [sqlite3_step()] has been called more recently than [sqlite3_reset()], 4991 ** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_() 4992 ** routine is passed a [prepared statement] that has been finalized, the 4993 ** result is undefined and probably harmful. 4994 ** 4995 ** ^Bindings are not cleared by the [sqlite3_reset()] routine. 4996 ** ^Unbound parameters are interpreted as NULL. 4997 ** 4998 ** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an 4999 ** [error code] if anything goes wrong. 5000 ** ^[SQLITE_TOOBIG] might be returned if the size of a string or BLOB 5001 ** exceeds limits imposed by [sqlite3_limit]([SQLITE_LIMIT_LENGTH]) or 5002 ** [SQLITE_MAX_LENGTH]. 5003 ** ^[SQLITE_RANGE] is returned if the parameter 5004 ** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails. 5005 ** 5006 ** See also: [sqlite3_bind_parameter_count()], 5007 ** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()]. 5008 */ 5009 SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*)); 5010 SQLITE_API int sqlite3_bind_blob64(sqlite3_stmt*, int, const void*, sqlite3_uint64, 5011 void(*)(void*)); 5012 SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double); 5013 SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int); 5014 SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64); 5015 SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int); 5016 SQLITE_API int sqlite3_bind_text(sqlite3_stmt*,int,const char*,int,void(*)(void*)); 5017 SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*)); 5018 SQLITE_API int sqlite3_bind_text64(sqlite3_stmt*, int, const char*, sqlite3_uint64, 5019 void(*)(void*), unsigned char encoding); 5020 SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*); 5021 SQLITE_API int sqlite3_bind_pointer(sqlite3_stmt*, int, void*, const char*,void(*)(void*)); 5022 SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n); 5023 SQLITE_API int sqlite3_bind_zeroblob64(sqlite3_stmt*, int, sqlite3_uint64); 5024 5025 /* 5026 ** CAPI3REF: Number Of SQL Parameters 5027 ** METHOD: sqlite3_stmt 5028 ** 5029 ** ^This routine can be used to find the number of [SQL parameters] 5030 ** in a [prepared statement]. SQL parameters are tokens of the 5031 ** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as 5032 ** placeholders for values that are [sqlite3_bind_blob | bound] 5033 ** to the parameters at a later time. 5034 ** 5035 ** ^(This routine actually returns the index of the largest (rightmost) 5036 ** parameter. For all forms except ?NNN, this will correspond to the 5037 ** number of unique parameters. If parameters of the ?NNN form are used, 5038 ** there may be gaps in the list.)^ 5039 ** 5040 ** See also: [sqlite3_bind_blob|sqlite3_bind()], 5041 ** [sqlite3_bind_parameter_name()], and 5042 ** [sqlite3_bind_parameter_index()]. 5043 */ 5044 SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*); 5045 5046 /* 5047 ** CAPI3REF: Name Of A Host Parameter 5048 ** METHOD: sqlite3_stmt 5049 ** 5050 ** ^The sqlite3_bind_parameter_name(P,N) interface returns 5051 ** the name of the N-th [SQL parameter] in the [prepared statement] P. 5052 ** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA" 5053 ** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA" 5054 ** respectively. 5055 ** In other words, the initial ":" or "$" or "@" or "?" 5056 ** is included as part of the name.)^ 5057 ** ^Parameters of the form "?" without a following integer have no name 5058 ** and are referred to as "nameless" or "anonymous parameters". 5059 ** 5060 ** ^The first host parameter has an index of 1, not 0. 5061 ** 5062 ** ^If the value N is out of range or if the N-th parameter is 5063 ** nameless, then NULL is returned. ^The returned string is 5064 ** always in UTF-8 encoding even if the named parameter was 5065 ** originally specified as UTF-16 in [sqlite3_prepare16()], 5066 ** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()]. 5067 ** 5068 ** See also: [sqlite3_bind_blob|sqlite3_bind()], 5069 ** [sqlite3_bind_parameter_count()], and 5070 ** [sqlite3_bind_parameter_index()]. 5071 */ 5072 SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int); 5073 5074 /* 5075 ** CAPI3REF: Index Of A Parameter With A Given Name 5076 ** METHOD: sqlite3_stmt 5077 ** 5078 ** ^Return the index of an SQL parameter given its name. ^The 5079 ** index value returned is suitable for use as the second 5080 ** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero 5081 ** is returned if no matching parameter is found. ^The parameter 5082 ** name must be given in UTF-8 even if the original statement 5083 ** was prepared from UTF-16 text using [sqlite3_prepare16_v2()] or 5084 ** [sqlite3_prepare16_v3()]. 5085 ** 5086 ** See also: [sqlite3_bind_blob|sqlite3_bind()], 5087 ** [sqlite3_bind_parameter_count()], and 5088 ** [sqlite3_bind_parameter_name()]. 5089 */ 5090 SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName); 5091 5092 /* 5093 ** CAPI3REF: Reset All Bindings On A Prepared Statement 5094 ** METHOD: sqlite3_stmt 5095 ** 5096 ** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset 5097 ** the [sqlite3_bind_blob | bindings] on a [prepared statement]. 5098 ** ^Use this routine to reset all host parameters to NULL. 5099 */ 5100 SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*); 5101 5102 /* 5103 ** CAPI3REF: Number Of Columns In A Result Set 5104 ** METHOD: sqlite3_stmt 5105 ** 5106 ** ^Return the number of columns in the result set returned by the 5107 ** [prepared statement]. ^If this routine returns 0, that means the 5108 ** [prepared statement] returns no data (for example an [UPDATE]). 5109 ** ^However, just because this routine returns a positive number does not 5110 ** mean that one or more rows of data will be returned. ^A SELECT statement 5111 ** will always have a positive sqlite3_column_count() but depending on the 5112 ** WHERE clause constraints and the table content, it might return no rows. 5113 ** 5114 ** See also: [sqlite3_data_count()] 5115 */ 5116 SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt); 5117 5118 /* 5119 ** CAPI3REF: Column Names In A Result Set 5120 ** METHOD: sqlite3_stmt 5121 ** 5122 ** ^These routines return the name assigned to a particular column 5123 ** in the result set of a [SELECT] statement. ^The sqlite3_column_name() 5124 ** interface returns a pointer to a zero-terminated UTF-8 string 5125 ** and sqlite3_column_name16() returns a pointer to a zero-terminated 5126 ** UTF-16 string. ^The first parameter is the [prepared statement] 5127 ** that implements the [SELECT] statement. ^The second parameter is the 5128 ** column number. ^The leftmost column is number 0. 5129 ** 5130 ** ^The returned string pointer is valid until either the [prepared statement] 5131 ** is destroyed by [sqlite3_finalize()] or until the statement is automatically 5132 ** reprepared by the first call to [sqlite3_step()] for a particular run 5133 ** or until the next call to 5134 ** sqlite3_column_name() or sqlite3_column_name16() on the same column. 5135 ** 5136 ** ^If sqlite3_malloc() fails during the processing of either routine 5137 ** (for example during a conversion from UTF-8 to UTF-16) then a 5138 ** NULL pointer is returned. 5139 ** 5140 ** ^The name of a result column is the value of the "AS" clause for 5141 ** that column, if there is an AS clause. If there is no AS clause 5142 ** then the name of the column is unspecified and may change from 5143 ** one release of SQLite to the next. 5144 */ 5145 SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N); 5146 SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N); 5147 5148 /* 5149 ** CAPI3REF: Source Of Data In A Query Result 5150 ** METHOD: sqlite3_stmt 5151 ** 5152 ** ^These routines provide a means to determine the database, table, and 5153 ** table column that is the origin of a particular result column in a 5154 ** [SELECT] statement. 5155 ** ^The name of the database or table or column can be returned as 5156 ** either a UTF-8 or UTF-16 string. ^The _database_ routines return 5157 ** the database name, the _table_ routines return the table name, and 5158 ** the origin_ routines return the column name. 5159 ** ^The returned string is valid until the [prepared statement] is destroyed 5160 ** using [sqlite3_finalize()] or until the statement is automatically 5161 ** reprepared by the first call to [sqlite3_step()] for a particular run 5162 ** or until the same information is requested 5163 ** again in a different encoding. 5164 ** 5165 ** ^The names returned are the original un-aliased names of the 5166 ** database, table, and column. 5167 ** 5168 ** ^The first argument to these interfaces is a [prepared statement]. 5169 ** ^These functions return information about the Nth result column returned by 5170 ** the statement, where N is the second function argument. 5171 ** ^The left-most column is column 0 for these routines. 5172 ** 5173 ** ^If the Nth column returned by the statement is an expression or 5174 ** subquery and is not a column value, then all of these functions return 5175 ** NULL. ^These routines might also return NULL if a memory allocation error 5176 ** occurs. ^Otherwise, they return the name of the attached database, table, 5177 ** or column that query result column was extracted from. 5178 ** 5179 ** ^As with all other SQLite APIs, those whose names end with "16" return 5180 ** UTF-16 encoded strings and the other functions return UTF-8. 5181 ** 5182 ** ^These APIs are only available if the library was compiled with the 5183 ** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol. 5184 ** 5185 ** If two or more threads call one or more 5186 ** [sqlite3_column_database_name | column metadata interfaces] 5187 ** for the same [prepared statement] and result column 5188 ** at the same time then the results are undefined. 5189 */ 5190 SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int); 5191 SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int); 5192 SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int); 5193 SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int); 5194 SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int); 5195 SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int); 5196 5197 /* 5198 ** CAPI3REF: Declared Datatype Of A Query Result 5199 ** METHOD: sqlite3_stmt 5200 ** 5201 ** ^(The first parameter is a [prepared statement]. 5202 ** If this statement is a [SELECT] statement and the Nth column of the 5203 ** returned result set of that [SELECT] is a table column (not an 5204 ** expression or subquery) then the declared type of the table 5205 ** column is returned.)^ ^If the Nth column of the result set is an 5206 ** expression or subquery, then a NULL pointer is returned. 5207 ** ^The returned string is always UTF-8 encoded. 5208 ** 5209 ** ^(For example, given the database schema: 5210 ** 5211 ** CREATE TABLE t1(c1 VARIANT); 5212 ** 5213 ** and the following statement to be compiled: 5214 ** 5215 ** SELECT c1 + 1, c1 FROM t1; 5216 ** 5217 ** this routine would return the string "VARIANT" for the second result 5218 ** column (i==1), and a NULL pointer for the first result column (i==0).)^ 5219 ** 5220 ** ^SQLite uses dynamic run-time typing. ^So just because a column 5221 ** is declared to contain a particular type does not mean that the 5222 ** data stored in that column is of the declared type. SQLite is 5223 ** strongly typed, but the typing is dynamic not static. ^Type 5224 ** is associated with individual values, not with the containers 5225 ** used to hold those values. 5226 */ 5227 SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int); 5228 SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int); 5229 5230 /* 5231 ** CAPI3REF: Evaluate An SQL Statement 5232 ** METHOD: sqlite3_stmt 5233 ** 5234 ** After a [prepared statement] has been prepared using any of 5235 ** [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], [sqlite3_prepare16_v2()], 5236 ** or [sqlite3_prepare16_v3()] or one of the legacy 5237 ** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function 5238 ** must be called one or more times to evaluate the statement. 5239 ** 5240 ** The details of the behavior of the sqlite3_step() interface depend 5241 ** on whether the statement was prepared using the newer "vX" interfaces 5242 ** [sqlite3_prepare_v3()], [sqlite3_prepare_v2()], [sqlite3_prepare16_v3()], 5243 ** [sqlite3_prepare16_v2()] or the older legacy 5244 ** interfaces [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the 5245 ** new "vX" interface is recommended for new applications but the legacy 5246 ** interface will continue to be supported. 5247 ** 5248 ** ^In the legacy interface, the return value will be either [SQLITE_BUSY], 5249 ** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE]. 5250 ** ^With the "v2" interface, any of the other [result codes] or 5251 ** [extended result codes] might be returned as well. 5252 ** 5253 ** ^[SQLITE_BUSY] means that the database engine was unable to acquire the 5254 ** database locks it needs to do its job. ^If the statement is a [COMMIT] 5255 ** or occurs outside of an explicit transaction, then you can retry the 5256 ** statement. If the statement is not a [COMMIT] and occurs within an 5257 ** explicit transaction then you should rollback the transaction before 5258 ** continuing. 5259 ** 5260 ** ^[SQLITE_DONE] means that the statement has finished executing 5261 ** successfully. sqlite3_step() should not be called again on this virtual 5262 ** machine without first calling [sqlite3_reset()] to reset the virtual 5263 ** machine back to its initial state. 5264 ** 5265 ** ^If the SQL statement being executed returns any data, then [SQLITE_ROW] 5266 ** is returned each time a new row of data is ready for processing by the 5267 ** caller. The values may be accessed using the [column access functions]. 5268 ** sqlite3_step() is called again to retrieve the next row of data. 5269 ** 5270 ** ^[SQLITE_ERROR] means that a run-time error (such as a constraint 5271 ** violation) has occurred. sqlite3_step() should not be called again on 5272 ** the VM. More information may be found by calling [sqlite3_errmsg()]. 5273 ** ^With the legacy interface, a more specific error code (for example, 5274 ** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth) 5275 ** can be obtained by calling [sqlite3_reset()] on the 5276 ** [prepared statement]. ^In the "v2" interface, 5277 ** the more specific error code is returned directly by sqlite3_step(). 5278 ** 5279 ** [SQLITE_MISUSE] means that the this routine was called inappropriately. 5280 ** Perhaps it was called on a [prepared statement] that has 5281 ** already been [sqlite3_finalize | finalized] or on one that had 5282 ** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could 5283 ** be the case that the same database connection is being used by two or 5284 ** more threads at the same moment in time. 5285 ** 5286 ** For all versions of SQLite up to and including 3.6.23.1, a call to 5287 ** [sqlite3_reset()] was required after sqlite3_step() returned anything 5288 ** other than [SQLITE_ROW] before any subsequent invocation of 5289 ** sqlite3_step(). Failure to reset the prepared statement using 5290 ** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from 5291 ** sqlite3_step(). But after [version 3.6.23.1] ([dateof:3.6.23.1]), 5292 ** sqlite3_step() began 5293 ** calling [sqlite3_reset()] automatically in this circumstance rather 5294 ** than returning [SQLITE_MISUSE]. This is not considered a compatibility 5295 ** break because any application that ever receives an SQLITE_MISUSE error 5296 ** is broken by definition. The [SQLITE_OMIT_AUTORESET] compile-time option 5297 ** can be used to restore the legacy behavior. 5298 ** 5299 ** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step() 5300 ** API always returns a generic error code, [SQLITE_ERROR], following any 5301 ** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call 5302 ** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the 5303 ** specific [error codes] that better describes the error. 5304 ** We admit that this is a goofy design. The problem has been fixed 5305 ** with the "v2" interface. If you prepare all of your SQL statements 5306 ** using [sqlite3_prepare_v3()] or [sqlite3_prepare_v2()] 5307 ** or [sqlite3_prepare16_v2()] or [sqlite3_prepare16_v3()] instead 5308 ** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces, 5309 ** then the more specific [error codes] are returned directly 5310 ** by sqlite3_step(). The use of the "vX" interfaces is recommended. 5311 */ 5312 SQLITE_API int sqlite3_step(sqlite3_stmt*); 5313 5314 /* 5315 ** CAPI3REF: Number of columns in a result set 5316 ** METHOD: sqlite3_stmt 5317 ** 5318 ** ^The sqlite3_data_count(P) interface returns the number of columns in the 5319 ** current row of the result set of [prepared statement] P. 5320 ** ^If prepared statement P does not have results ready to return 5321 ** (via calls to the [sqlite3_column_int | sqlite3_column()] family of 5322 ** interfaces) then sqlite3_data_count(P) returns 0. 5323 ** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer. 5324 ** ^The sqlite3_data_count(P) routine returns 0 if the previous call to 5325 ** [sqlite3_step](P) returned [SQLITE_DONE]. ^The sqlite3_data_count(P) 5326 ** will return non-zero if previous call to [sqlite3_step](P) returned 5327 ** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum] 5328 ** where it always returns zero since each step of that multi-step 5329 ** pragma returns 0 columns of data. 5330 ** 5331 ** See also: [sqlite3_column_count()] 5332 */ 5333 SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt); 5334 5335 /* 5336 ** CAPI3REF: Fundamental Datatypes 5337 ** KEYWORDS: SQLITE_TEXT 5338 ** 5339 ** ^(Every value in SQLite has one of five fundamental datatypes: 5340 ** 5341 ** <ul> 5342 ** <li> 64-bit signed integer 5343 ** <li> 64-bit IEEE floating point number 5344 ** <li> string 5345 ** <li> BLOB 5346 ** <li> NULL 5347 ** </ul>)^ 5348 ** 5349 ** These constants are codes for each of those types. 5350 ** 5351 ** Note that the SQLITE_TEXT constant was also used in SQLite version 2 5352 ** for a completely different meaning. Software that links against both 5353 ** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not 5354 ** SQLITE_TEXT. 5355 */ 5356 #define SQLITE_INTEGER 1 5357 #define SQLITE_FLOAT 2 5358 #define SQLITE_BLOB 4 5359 #define SQLITE_NULL 5 5360 #ifdef SQLITE_TEXT 5361 # undef SQLITE_TEXT 5362 #else 5363 # define SQLITE_TEXT 3 5364 #endif 5365 #define SQLITE3_TEXT 3 5366 5367 /* 5368 ** CAPI3REF: Result Values From A Query 5369 ** KEYWORDS: {column access functions} 5370 ** METHOD: sqlite3_stmt 5371 ** 5372 ** <b>Summary:</b> 5373 ** <blockquote><table border=0 cellpadding=0 cellspacing=0> 5374 ** <tr><td><b>sqlite3_column_blob</b><td>→<td>BLOB result 5375 ** <tr><td><b>sqlite3_column_double</b><td>→<td>REAL result 5376 ** <tr><td><b>sqlite3_column_int</b><td>→<td>32-bit INTEGER result 5377 ** <tr><td><b>sqlite3_column_int64</b><td>→<td>64-bit INTEGER result 5378 ** <tr><td><b>sqlite3_column_text</b><td>→<td>UTF-8 TEXT result 5379 ** <tr><td><b>sqlite3_column_text16</b><td>→<td>UTF-16 TEXT result 5380 ** <tr><td><b>sqlite3_column_value</b><td>→<td>The result as an 5381 ** [sqlite3_value|unprotected sqlite3_value] object. 5382 ** <tr><td> <td> <td> 5383 ** <tr><td><b>sqlite3_column_bytes</b><td>→<td>Size of a BLOB 5384 ** or a UTF-8 TEXT result in bytes 5385 ** <tr><td><b>sqlite3_column_bytes16 </b> 5386 ** <td>→ <td>Size of UTF-16 5387 ** TEXT in bytes 5388 ** <tr><td><b>sqlite3_column_type</b><td>→<td>Default 5389 ** datatype of the result 5390 ** </table></blockquote> 5391 ** 5392 ** <b>Details:</b> 5393 ** 5394 ** ^These routines return information about a single column of the current 5395 ** result row of a query. ^In every case the first argument is a pointer 5396 ** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*] 5397 ** that was returned from [sqlite3_prepare_v2()] or one of its variants) 5398 ** and the second argument is the index of the column for which information 5399 ** should be returned. ^The leftmost column of the result set has the index 0. 5400 ** ^The number of columns in the result can be determined using 5401 ** [sqlite3_column_count()]. 5402 ** 5403 ** If the SQL statement does not currently point to a valid row, or if the 5404 ** column index is out of range, the result is undefined. 5405 ** These routines may only be called when the most recent call to 5406 ** [sqlite3_step()] has returned [SQLITE_ROW] and neither 5407 ** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently. 5408 ** If any of these routines are called after [sqlite3_reset()] or 5409 ** [sqlite3_finalize()] or after [sqlite3_step()] has returned 5410 ** something other than [SQLITE_ROW], the results are undefined. 5411 ** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()] 5412 ** are called from a different thread while any of these routines 5413 ** are pending, then the results are undefined. 5414 ** 5415 ** The first six interfaces (_blob, _double, _int, _int64, _text, and _text16) 5416 ** each return the value of a result column in a specific data format. If 5417 ** the result column is not initially in the requested format (for example, 5418 ** if the query returns an integer but the sqlite3_column_text() interface 5419 ** is used to extract the value) then an automatic type conversion is performed. 5420 ** 5421 ** ^The sqlite3_column_type() routine returns the 5422 ** [SQLITE_INTEGER | datatype code] for the initial data type 5423 ** of the result column. ^The returned value is one of [SQLITE_INTEGER], 5424 ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. 5425 ** The return value of sqlite3_column_type() can be used to decide which 5426 ** of the first six interface should be used to extract the column value. 5427 ** The value returned by sqlite3_column_type() is only meaningful if no 5428 ** automatic type conversions have occurred for the value in question. 5429 ** After a type conversion, the result of calling sqlite3_column_type() 5430 ** is undefined, though harmless. Future 5431 ** versions of SQLite may change the behavior of sqlite3_column_type() 5432 ** following a type conversion. 5433 ** 5434 ** If the result is a BLOB or a TEXT string, then the sqlite3_column_bytes() 5435 ** or sqlite3_column_bytes16() interfaces can be used to determine the size 5436 ** of that BLOB or string. 5437 ** 5438 ** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes() 5439 ** routine returns the number of bytes in that BLOB or string. 5440 ** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts 5441 ** the string to UTF-8 and then returns the number of bytes. 5442 ** ^If the result is a numeric value then sqlite3_column_bytes() uses 5443 ** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns 5444 ** the number of bytes in that string. 5445 ** ^If the result is NULL, then sqlite3_column_bytes() returns zero. 5446 ** 5447 ** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16() 5448 ** routine returns the number of bytes in that BLOB or string. 5449 ** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts 5450 ** the string to UTF-16 and then returns the number of bytes. 5451 ** ^If the result is a numeric value then sqlite3_column_bytes16() uses 5452 ** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns 5453 ** the number of bytes in that string. 5454 ** ^If the result is NULL, then sqlite3_column_bytes16() returns zero. 5455 ** 5456 ** ^The values returned by [sqlite3_column_bytes()] and 5457 ** [sqlite3_column_bytes16()] do not include the zero terminators at the end 5458 ** of the string. ^For clarity: the values returned by 5459 ** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of 5460 ** bytes in the string, not the number of characters. 5461 ** 5462 ** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(), 5463 ** even empty strings, are always zero-terminated. ^The return 5464 ** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer. 5465 ** 5466 ** ^Strings returned by sqlite3_column_text16() always have the endianness 5467 ** which is native to the platform, regardless of the text encoding set 5468 ** for the database. 5469 ** 5470 ** <b>Warning:</b> ^The object returned by [sqlite3_column_value()] is an 5471 ** [unprotected sqlite3_value] object. In a multithreaded environment, 5472 ** an unprotected sqlite3_value object may only be used safely with 5473 ** [sqlite3_bind_value()] and [sqlite3_result_value()]. 5474 ** If the [unprotected sqlite3_value] object returned by 5475 ** [sqlite3_column_value()] is used in any other way, including calls 5476 ** to routines like [sqlite3_value_int()], [sqlite3_value_text()], 5477 ** or [sqlite3_value_bytes()], the behavior is not threadsafe. 5478 ** Hence, the sqlite3_column_value() interface 5479 ** is normally only useful within the implementation of 5480 ** [application-defined SQL functions] or [virtual tables], not within 5481 ** top-level application code. 5482 ** 5483 ** These routines may attempt to convert the datatype of the result. 5484 ** ^For example, if the internal representation is FLOAT and a text result 5485 ** is requested, [sqlite3_snprintf()] is used internally to perform the 5486 ** conversion automatically. ^(The following table details the conversions 5487 ** that are applied: 5488 ** 5489 ** <blockquote> 5490 ** <table border="1"> 5491 ** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion 5492 ** 5493 ** <tr><td> NULL <td> INTEGER <td> Result is 0 5494 ** <tr><td> NULL <td> FLOAT <td> Result is 0.0 5495 ** <tr><td> NULL <td> TEXT <td> Result is a NULL pointer 5496 ** <tr><td> NULL <td> BLOB <td> Result is a NULL pointer 5497 ** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float 5498 ** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer 5499 ** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT 5500 ** <tr><td> FLOAT <td> INTEGER <td> [CAST] to INTEGER 5501 ** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float 5502 ** <tr><td> FLOAT <td> BLOB <td> [CAST] to BLOB 5503 ** <tr><td> TEXT <td> INTEGER <td> [CAST] to INTEGER 5504 ** <tr><td> TEXT <td> FLOAT <td> [CAST] to REAL 5505 ** <tr><td> TEXT <td> BLOB <td> No change 5506 ** <tr><td> BLOB <td> INTEGER <td> [CAST] to INTEGER 5507 ** <tr><td> BLOB <td> FLOAT <td> [CAST] to REAL 5508 ** <tr><td> BLOB <td> TEXT <td> [CAST] to TEXT, ensure zero terminator 5509 ** </table> 5510 ** </blockquote>)^ 5511 ** 5512 ** Note that when type conversions occur, pointers returned by prior 5513 ** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or 5514 ** sqlite3_column_text16() may be invalidated. 5515 ** Type conversions and pointer invalidations might occur 5516 ** in the following cases: 5517 ** 5518 ** <ul> 5519 ** <li> The initial content is a BLOB and sqlite3_column_text() or 5520 ** sqlite3_column_text16() is called. A zero-terminator might 5521 ** need to be added to the string.</li> 5522 ** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or 5523 ** sqlite3_column_text16() is called. The content must be converted 5524 ** to UTF-16.</li> 5525 ** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or 5526 ** sqlite3_column_text() is called. The content must be converted 5527 ** to UTF-8.</li> 5528 ** </ul> 5529 ** 5530 ** ^Conversions between UTF-16be and UTF-16le are always done in place and do 5531 ** not invalidate a prior pointer, though of course the content of the buffer 5532 ** that the prior pointer references will have been modified. Other kinds 5533 ** of conversion are done in place when it is possible, but sometimes they 5534 ** are not possible and in those cases prior pointers are invalidated. 5535 ** 5536 ** The safest policy is to invoke these routines 5537 ** in one of the following ways: 5538 ** 5539 ** <ul> 5540 ** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li> 5541 ** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li> 5542 ** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li> 5543 ** </ul> 5544 ** 5545 ** In other words, you should call sqlite3_column_text(), 5546 ** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result 5547 ** into the desired format, then invoke sqlite3_column_bytes() or 5548 ** sqlite3_column_bytes16() to find the size of the result. Do not mix calls 5549 ** to sqlite3_column_text() or sqlite3_column_blob() with calls to 5550 ** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16() 5551 ** with calls to sqlite3_column_bytes(). 5552 ** 5553 ** ^The pointers returned are valid until a type conversion occurs as 5554 ** described above, or until [sqlite3_step()] or [sqlite3_reset()] or 5555 ** [sqlite3_finalize()] is called. ^The memory space used to hold strings 5556 ** and BLOBs is freed automatically. Do not pass the pointers returned 5557 ** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into 5558 ** [sqlite3_free()]. 5559 ** 5560 ** As long as the input parameters are correct, these routines will only 5561 ** fail if an out-of-memory error occurs during a format conversion. 5562 ** Only the following subset of interfaces are subject to out-of-memory 5563 ** errors: 5564 ** 5565 ** <ul> 5566 ** <li> sqlite3_column_blob() 5567 ** <li> sqlite3_column_text() 5568 ** <li> sqlite3_column_text16() 5569 ** <li> sqlite3_column_bytes() 5570 ** <li> sqlite3_column_bytes16() 5571 ** </ul> 5572 ** 5573 ** If an out-of-memory error occurs, then the return value from these 5574 ** routines is the same as if the column had contained an SQL NULL value. 5575 ** Valid SQL NULL returns can be distinguished from out-of-memory errors 5576 ** by invoking the [sqlite3_errcode()] immediately after the suspect 5577 ** return value is obtained and before any 5578 ** other SQLite interface is called on the same [database connection]. 5579 */ 5580 SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol); 5581 SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol); 5582 SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol); 5583 SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol); 5584 SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol); 5585 SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol); 5586 SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol); 5587 SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol); 5588 SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol); 5589 SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol); 5590 5591 /* 5592 ** CAPI3REF: Destroy A Prepared Statement Object 5593 ** DESTRUCTOR: sqlite3_stmt 5594 ** 5595 ** ^The sqlite3_finalize() function is called to delete a [prepared statement]. 5596 ** ^If the most recent evaluation of the statement encountered no errors 5597 ** or if the statement has never been evaluated, then sqlite3_finalize() returns 5598 ** SQLITE_OK. ^If the most recent evaluation of statement S failed, then 5599 ** sqlite3_finalize(S) returns the appropriate [error code] or 5600 ** [extended error code]. 5601 ** 5602 ** ^The sqlite3_finalize(S) routine can be called at any point during 5603 ** the life cycle of [prepared statement] S: 5604 ** before statement S is ever evaluated, after 5605 ** one or more calls to [sqlite3_reset()], or after any call 5606 ** to [sqlite3_step()] regardless of whether or not the statement has 5607 ** completed execution. 5608 ** 5609 ** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op. 5610 ** 5611 ** The application must finalize every [prepared statement] in order to avoid 5612 ** resource leaks. It is a grievous error for the application to try to use 5613 ** a prepared statement after it has been finalized. Any use of a prepared 5614 ** statement after it has been finalized can result in undefined and 5615 ** undesirable behavior such as segfaults and heap corruption. 5616 */ 5617 SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt); 5618 5619 /* 5620 ** CAPI3REF: Reset A Prepared Statement Object 5621 ** METHOD: sqlite3_stmt 5622 ** 5623 ** The sqlite3_reset() function is called to reset a [prepared statement] 5624 ** object back to its initial state, ready to be re-executed. 5625 ** ^Any SQL statement variables that had values bound to them using 5626 ** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values. 5627 ** Use [sqlite3_clear_bindings()] to reset the bindings. 5628 ** 5629 ** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S 5630 ** back to the beginning of its program. 5631 ** 5632 ** ^The return code from [sqlite3_reset(S)] indicates whether or not 5633 ** the previous evaluation of prepared statement S completed successfully. 5634 ** ^If [sqlite3_step(S)] has never before been called on S or if 5635 ** [sqlite3_step(S)] has not been called since the previous call 5636 ** to [sqlite3_reset(S)], then [sqlite3_reset(S)] will return 5637 ** [SQLITE_OK]. 5638 ** 5639 ** ^If the most recent call to [sqlite3_step(S)] for the 5640 ** [prepared statement] S indicated an error, then 5641 ** [sqlite3_reset(S)] returns an appropriate [error code]. 5642 ** ^The [sqlite3_reset(S)] interface might also return an [error code] 5643 ** if there were no prior errors but the process of resetting 5644 ** the prepared statement caused a new error. ^For example, if an 5645 ** [INSERT] statement with a [RETURNING] clause is only stepped one time, 5646 ** that one call to [sqlite3_step(S)] might return SQLITE_ROW but 5647 ** the overall statement might still fail and the [sqlite3_reset(S)] call 5648 ** might return SQLITE_BUSY if locking constraints prevent the 5649 ** database change from committing. Therefore, it is important that 5650 ** applications check the return code from [sqlite3_reset(S)] even if 5651 ** no prior call to [sqlite3_step(S)] indicated a problem. 5652 ** 5653 ** ^The [sqlite3_reset(S)] interface does not change the values 5654 ** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S. 5655 */ 5656 SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt); 5657 5658 5659 /* 5660 ** CAPI3REF: Create Or Redefine SQL Functions 5661 ** KEYWORDS: {function creation routines} 5662 ** METHOD: sqlite3 5663 ** 5664 ** ^These functions (collectively known as "function creation routines") 5665 ** are used to add SQL functions or aggregates or to redefine the behavior 5666 ** of existing SQL functions or aggregates. The only differences between 5667 ** the three "sqlite3_create_function*" routines are the text encoding 5668 ** expected for the second parameter (the name of the function being 5669 ** created) and the presence or absence of a destructor callback for 5670 ** the application data pointer. Function sqlite3_create_window_function() 5671 ** is similar, but allows the user to supply the extra callback functions 5672 ** needed by [aggregate window functions]. 5673 ** 5674 ** ^The first parameter is the [database connection] to which the SQL 5675 ** function is to be added. ^If an application uses more than one database 5676 ** connection then application-defined SQL functions must be added 5677 ** to each database connection separately. 5678 ** 5679 ** ^The second parameter is the name of the SQL function to be created or 5680 ** redefined. ^The length of the name is limited to 255 bytes in a UTF-8 5681 ** representation, exclusive of the zero-terminator. ^Note that the name 5682 ** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes. 5683 ** ^Any attempt to create a function with a longer name 5684 ** will result in [SQLITE_MISUSE] being returned. 5685 ** 5686 ** ^The third parameter (nArg) 5687 ** is the number of arguments that the SQL function or 5688 ** aggregate takes. ^If this parameter is -1, then the SQL function or 5689 ** aggregate may take any number of arguments between 0 and the limit 5690 ** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third 5691 ** parameter is less than -1 or greater than 127 then the behavior is 5692 ** undefined. 5693 ** 5694 ** ^The fourth parameter, eTextRep, specifies what 5695 ** [SQLITE_UTF8 | text encoding] this SQL function prefers for 5696 ** its parameters. The application should set this parameter to 5697 ** [SQLITE_UTF16LE] if the function implementation invokes 5698 ** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the 5699 ** implementation invokes [sqlite3_value_text16be()] on an input, or 5700 ** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8] 5701 ** otherwise. ^The same SQL function may be registered multiple times using 5702 ** different preferred text encodings, with different implementations for 5703 ** each encoding. 5704 ** ^When multiple implementations of the same function are available, SQLite 5705 ** will pick the one that involves the least amount of data conversion. 5706 ** 5707 ** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC] 5708 ** to signal that the function will always return the same result given 5709 ** the same inputs within a single SQL statement. Most SQL functions are 5710 ** deterministic. The built-in [random()] SQL function is an example of a 5711 ** function that is not deterministic. The SQLite query planner is able to 5712 ** perform additional optimizations on deterministic functions, so use 5713 ** of the [SQLITE_DETERMINISTIC] flag is recommended where possible. 5714 ** 5715 ** ^The fourth parameter may also optionally include the [SQLITE_DIRECTONLY] 5716 ** flag, which if present prevents the function from being invoked from 5717 ** within VIEWs, TRIGGERs, CHECK constraints, generated column expressions, 5718 ** index expressions, or the WHERE clause of partial indexes. 5719 ** 5720 ** For best security, the [SQLITE_DIRECTONLY] flag is recommended for 5721 ** all application-defined SQL functions that do not need to be 5722 ** used inside of triggers, views, CHECK constraints, or other elements of 5723 ** the database schema. This flag is especially recommended for SQL 5724 ** functions that have side effects or reveal internal application state. 5725 ** Without this flag, an attacker might be able to modify the schema of 5726 ** a database file to include invocations of the function with parameters 5727 ** chosen by the attacker, which the application will then execute when 5728 ** the database file is opened and read. 5729 ** 5730 ** ^(The fifth parameter is an arbitrary pointer. The implementation of the 5731 ** function can gain access to this pointer using [sqlite3_user_data()].)^ 5732 ** 5733 ** ^The sixth, seventh and eighth parameters passed to the three 5734 ** "sqlite3_create_function*" functions, xFunc, xStep and xFinal, are 5735 ** pointers to C-language functions that implement the SQL function or 5736 ** aggregate. ^A scalar SQL function requires an implementation of the xFunc 5737 ** callback only; NULL pointers must be passed as the xStep and xFinal 5738 ** parameters. ^An aggregate SQL function requires an implementation of xStep 5739 ** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing 5740 ** SQL function or aggregate, pass NULL pointers for all three function 5741 ** callbacks. 5742 ** 5743 ** ^The sixth, seventh, eighth and ninth parameters (xStep, xFinal, xValue 5744 ** and xInverse) passed to sqlite3_create_window_function are pointers to 5745 ** C-language callbacks that implement the new function. xStep and xFinal 5746 ** must both be non-NULL. xValue and xInverse may either both be NULL, in 5747 ** which case a regular aggregate function is created, or must both be 5748 ** non-NULL, in which case the new function may be used as either an aggregate 5749 ** or aggregate window function. More details regarding the implementation 5750 ** of aggregate window functions are 5751 ** [user-defined window functions|available here]. 5752 ** 5753 ** ^(If the final parameter to sqlite3_create_function_v2() or 5754 ** sqlite3_create_window_function() is not NULL, then it is the destructor for 5755 ** the application data pointer. The destructor is invoked when the function 5756 ** is deleted, either by being overloaded or when the database connection 5757 ** closes.)^ ^The destructor is also invoked if the call to 5758 ** sqlite3_create_function_v2() fails. ^When the destructor callback is 5759 ** invoked, it is passed a single argument which is a copy of the application 5760 ** data pointer which was the fifth parameter to sqlite3_create_function_v2(). 5761 ** 5762 ** ^It is permitted to register multiple implementations of the same 5763 ** functions with the same name but with either differing numbers of 5764 ** arguments or differing preferred text encodings. ^SQLite will use 5765 ** the implementation that most closely matches the way in which the 5766 ** SQL function is used. ^A function implementation with a non-negative 5767 ** nArg parameter is a better match than a function implementation with 5768 ** a negative nArg. ^A function where the preferred text encoding 5769 ** matches the database encoding is a better 5770 ** match than a function where the encoding is different. 5771 ** ^A function where the encoding difference is between UTF16le and UTF16be 5772 ** is a closer match than a function where the encoding difference is 5773 ** between UTF8 and UTF16. 5774 ** 5775 ** ^Built-in functions may be overloaded by new application-defined functions. 5776 ** 5777 ** ^An application-defined function is permitted to call other 5778 ** SQLite interfaces. However, such calls must not 5779 ** close the database connection nor finalize or reset the prepared 5780 ** statement in which the function is running. 5781 */ 5782 SQLITE_API int sqlite3_create_function( 5783 sqlite3 *db, 5784 const char *zFunctionName, 5785 int nArg, 5786 int eTextRep, 5787 void *pApp, 5788 void (*xFunc)(sqlite3_context*,int,sqlite3_value**), 5789 void (*xStep)(sqlite3_context*,int,sqlite3_value**), 5790 void (*xFinal)(sqlite3_context*) 5791 ); 5792 SQLITE_API int sqlite3_create_function16( 5793 sqlite3 *db, 5794 const void *zFunctionName, 5795 int nArg, 5796 int eTextRep, 5797 void *pApp, 5798 void (*xFunc)(sqlite3_context*,int,sqlite3_value**), 5799 void (*xStep)(sqlite3_context*,int,sqlite3_value**), 5800 void (*xFinal)(sqlite3_context*) 5801 ); 5802 SQLITE_API int sqlite3_create_function_v2( 5803 sqlite3 *db, 5804 const char *zFunctionName, 5805 int nArg, 5806 int eTextRep, 5807 void *pApp, 5808 void (*xFunc)(sqlite3_context*,int,sqlite3_value**), 5809 void (*xStep)(sqlite3_context*,int,sqlite3_value**), 5810 void (*xFinal)(sqlite3_context*), 5811 void(*xDestroy)(void*) 5812 ); 5813 SQLITE_API int sqlite3_create_window_function( 5814 sqlite3 *db, 5815 const char *zFunctionName, 5816 int nArg, 5817 int eTextRep, 5818 void *pApp, 5819 void (*xStep)(sqlite3_context*,int,sqlite3_value**), 5820 void (*xFinal)(sqlite3_context*), 5821 void (*xValue)(sqlite3_context*), 5822 void (*xInverse)(sqlite3_context*,int,sqlite3_value**), 5823 void(*xDestroy)(void*) 5824 ); 5825 5826 /* 5827 ** CAPI3REF: Text Encodings 5828 ** 5829 ** These constants define integer codes that represent the various 5830 ** text encodings supported by SQLite. 5831 ** 5832 ** <dl> 5833 ** [[SQLITE_UTF8]] <dt>SQLITE_UTF8</dt><dd>Text is encoding as UTF-8</dd> 5834 ** 5835 ** [[SQLITE_UTF16LE]] <dt>SQLITE_UTF16LE</dt><dd>Text is encoding as UTF-16 5836 ** with each code point being expressed "little endian" - the least significant 5837 ** byte first. This is the usual encoding, for example on Windows.</dd> 5838 ** 5839 ** [[SQLITE_UTF16BE]] <dt>SQLITE_UTF16BE</dt><dd>Text is encoding as UTF-16 5840 ** with each code point being expressed "big endian" - the most significant 5841 ** byte first. This encoding is less common, but is still sometimes seen, 5842 ** specially on older systems. 5843 ** 5844 ** [[SQLITE_UTF16]] <dt>SQLITE_UTF16</dt><dd>Text is encoding as UTF-16 5845 ** with each code point being expressed either little endian or as big 5846 ** endian, according to the native endianness of the host computer. 5847 ** 5848 ** [[SQLITE_ANY]] <dt>SQLITE_ANY</dt><dd>This encoding value may only be used 5849 ** to declare the preferred text for [application-defined SQL functions] 5850 ** created using [sqlite3_create_function()] and similar. If the preferred 5851 ** encoding (the 4th parameter to sqlite3_create_function() - the eTextRep 5852 ** parameter) is SQLITE_ANY, that indicates that the function does not have 5853 ** a preference regarding the text encoding of its parameters and can take 5854 ** any text encoding that the SQLite core find convenient to supply. This 5855 ** option is deprecated. Please do not use it in new applications. 5856 ** 5857 ** [[SQLITE_UTF16_ALIGNED]] <dt>SQLITE_UTF16_ALIGNED</dt><dd>This encoding 5858 ** value may be used as the 3rd parameter (the eTextRep parameter) to 5859 ** [sqlite3_create_collation()] and similar. This encoding value means 5860 ** that the application-defined collating sequence created expects its 5861 ** input strings to be in UTF16 in native byte order, and that the start 5862 ** of the strings must be aligned to a 2-byte boundary. 5863 ** 5864 ** [[SQLITE_UTF8_ZT]] <dt>SQLITE_UTF8_ZT</dt><dd>This option can only be 5865 ** used to specify the text encoding to strings input to 5866 ** [sqlite3_result_text64()] and [sqlite3_bind_text64()]. 5867 ** The SQLITE_UTF8_ZT encoding means that the input string (call it "z") 5868 ** is UTF-8 encoded and that it is zero-terminated. If the length parameter 5869 ** (call it "n") is non-negative, this encoding option means that the caller 5870 ** guarantees that z array contains at least n+1 bytes and that the z[n] 5871 ** byte has a value of zero. 5872 ** This option gives the same output as SQLITE_UTF8, but can be more efficient 5873 ** by avoiding the need to make a copy of the input string, in some cases. 5874 ** However, if z is allocated to hold fewer than n+1 bytes or if the 5875 ** z[n] byte is not zero, undefined behavior may result. 5876 ** </dl> 5877 */ 5878 #define SQLITE_UTF8 1 /* IMP: R-37514-35566 */ 5879 #define SQLITE_UTF16LE 2 /* IMP: R-03371-37637 */ 5880 #define SQLITE_UTF16BE 3 /* IMP: R-51971-34154 */ 5881 #define SQLITE_UTF16 4 /* Use native byte order */ 5882 #define SQLITE_ANY 5 /* Deprecated */ 5883 #define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */ 5884 #define SQLITE_UTF8_ZT 16 /* Zero-terminated UTF8 */ 5885 5886 /* 5887 ** CAPI3REF: Function Flags 5888 ** 5889 ** These constants may be ORed together with the 5890 ** [SQLITE_UTF8 | preferred text encoding] as the fourth argument 5891 ** to [sqlite3_create_function()], [sqlite3_create_function16()], or 5892 ** [sqlite3_create_function_v2()]. 5893 ** 5894 ** <dl> 5895 ** [[SQLITE_DETERMINISTIC]] <dt>SQLITE_DETERMINISTIC</dt><dd> 5896 ** The SQLITE_DETERMINISTIC flag means that the new function always gives 5897 ** the same output when the input parameters are the same. 5898 ** The [abs|abs() function] is deterministic, for example, but 5899 ** [randomblob|randomblob()] is not. Functions must 5900 ** be deterministic in order to be used in certain contexts such as 5901 ** with the WHERE clause of [partial indexes] or in [generated columns]. 5902 ** SQLite might also optimize deterministic functions by factoring them 5903 ** out of inner loops. 5904 ** </dd> 5905 ** 5906 ** [[SQLITE_DIRECTONLY]] <dt>SQLITE_DIRECTONLY</dt><dd> 5907 ** The SQLITE_DIRECTONLY flag means that the function may only be invoked 5908 ** from top-level SQL, and cannot be used in VIEWs or TRIGGERs nor in 5909 ** schema structures such as [CHECK constraints], [DEFAULT clauses], 5910 ** [expression indexes], [partial indexes], or [generated columns]. 5911 ** <p> 5912 ** The SQLITE_DIRECTONLY flag is recommended for any 5913 ** [application-defined SQL function] 5914 ** that has side-effects or that could potentially leak sensitive information. 5915 ** This will prevent attacks in which an application is tricked 5916 ** into using a database file that has had its schema surreptitiously 5917 ** modified to invoke the application-defined function in ways that are 5918 ** harmful. 5919 ** <p> 5920 ** Some people say it is good practice to set SQLITE_DIRECTONLY on all 5921 ** [application-defined SQL functions], regardless of whether or not they 5922 ** are security sensitive, as doing so prevents those functions from being used 5923 ** inside of the database schema, and thus ensures that the database 5924 ** can be inspected and modified using generic tools (such as the [CLI]) 5925 ** that do not have access to the application-defined functions. 5926 ** </dd> 5927 ** 5928 ** [[SQLITE_INNOCUOUS]] <dt>SQLITE_INNOCUOUS</dt><dd> 5929 ** The SQLITE_INNOCUOUS flag means that the function is unlikely 5930 ** to cause problems even if misused. An innocuous function should have 5931 ** no side effects and should not depend on any values other than its 5932 ** input parameters. The [abs|abs() function] is an example of an 5933 ** innocuous function. 5934 ** The [load_extension() SQL function] is not innocuous because of its 5935 ** side effects. 5936 ** <p> SQLITE_INNOCUOUS is similar to SQLITE_DETERMINISTIC, but is not 5937 ** exactly the same. The [random|random() function] is an example of a 5938 ** function that is innocuous but not deterministic. 5939 ** <p>Some heightened security settings 5940 ** ([SQLITE_DBCONFIG_TRUSTED_SCHEMA] and [PRAGMA trusted_schema=OFF]) 5941 ** disable the use of SQL functions inside views and triggers and in 5942 ** schema structures such as [CHECK constraints], [DEFAULT clauses], 5943 ** [expression indexes], [partial indexes], and [generated columns] unless 5944 ** the function is tagged with SQLITE_INNOCUOUS. Most built-in functions 5945 ** are innocuous. Developers are advised to avoid using the 5946 ** SQLITE_INNOCUOUS flag for application-defined functions unless the 5947 ** function has been carefully audited and found to be free of potentially 5948 ** security-adverse side-effects and information-leaks. 5949 ** </dd> 5950 ** 5951 ** [[SQLITE_SUBTYPE]] <dt>SQLITE_SUBTYPE</dt><dd> 5952 ** The SQLITE_SUBTYPE flag indicates to SQLite that a function might call 5953 ** [sqlite3_value_subtype()] to inspect the sub-types of its arguments. 5954 ** This flag instructs SQLite to omit some corner-case optimizations that 5955 ** might disrupt the operation of the [sqlite3_value_subtype()] function, 5956 ** causing it to return zero rather than the correct subtype(). 5957 ** All SQL functions that invoke [sqlite3_value_subtype()] should have this 5958 ** property. If the SQLITE_SUBTYPE property is omitted, then the return 5959 ** value from [sqlite3_value_subtype()] might sometimes be zero even though 5960 ** a non-zero subtype was specified by the function argument expression. 5961 ** 5962 ** [[SQLITE_RESULT_SUBTYPE]] <dt>SQLITE_RESULT_SUBTYPE</dt><dd> 5963 ** The SQLITE_RESULT_SUBTYPE flag indicates to SQLite that a function might call 5964 ** [sqlite3_result_subtype()] to cause a sub-type to be associated with its 5965 ** result. 5966 ** Every function that invokes [sqlite3_result_subtype()] should have this 5967 ** property. If it does not, then the call to [sqlite3_result_subtype()] 5968 ** might become a no-op if the function is used as a term in an 5969 ** [expression index]. On the other hand, SQL functions that never invoke 5970 ** [sqlite3_result_subtype()] should avoid setting this property, as the 5971 ** purpose of this property is to disable certain optimizations that are 5972 ** incompatible with subtypes. 5973 ** 5974 ** [[SQLITE_SELFORDER1]] <dt>SQLITE_SELFORDER1</dt><dd> 5975 ** The SQLITE_SELFORDER1 flag indicates that the function is an aggregate 5976 ** that internally orders the values provided to the first argument. The 5977 ** ordered-set aggregate SQL notation with a single ORDER BY term can be 5978 ** used to invoke this function. If the ordered-set aggregate notation is 5979 ** used on a function that lacks this flag, then an error is raised. Note 5980 ** that the ordered-set aggregate syntax is only available if SQLite is 5981 ** built using the -DSQLITE_ENABLE_ORDERED_SET_AGGREGATES compile-time option. 5982 ** </dd> 5983 ** </dl> 5984 */ 5985 #define SQLITE_DETERMINISTIC 0x000000800 5986 #define SQLITE_DIRECTONLY 0x000080000 5987 #define SQLITE_SUBTYPE 0x000100000 5988 #define SQLITE_INNOCUOUS 0x000200000 5989 #define SQLITE_RESULT_SUBTYPE 0x001000000 5990 #define SQLITE_SELFORDER1 0x002000000 5991 5992 /* 5993 ** CAPI3REF: Deprecated Functions 5994 ** DEPRECATED 5995 ** 5996 ** These functions are [deprecated]. In order to maintain 5997 ** backwards compatibility with older code, these functions continue 5998 ** to be supported. However, new applications should avoid 5999 ** the use of these functions. To encourage programmers to avoid 6000 ** these functions, we will not explain what they do. 6001 */ 6002 #ifndef SQLITE_OMIT_DEPRECATED 6003 SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*); 6004 SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*); 6005 SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*); 6006 SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void); 6007 SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void); 6008 SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int), 6009 void*,sqlite3_int64); 6010 #endif 6011 6012 /* 6013 ** CAPI3REF: Obtaining SQL Values 6014 ** METHOD: sqlite3_value 6015 ** 6016 ** <b>Summary:</b> 6017 ** <blockquote><table border=0 cellpadding=0 cellspacing=0> 6018 ** <tr><td><b>sqlite3_value_blob</b><td>→<td>BLOB value 6019 ** <tr><td><b>sqlite3_value_double</b><td>→<td>REAL value 6020 ** <tr><td><b>sqlite3_value_int</b><td>→<td>32-bit INTEGER value 6021 ** <tr><td><b>sqlite3_value_int64</b><td>→<td>64-bit INTEGER value 6022 ** <tr><td><b>sqlite3_value_pointer</b><td>→<td>Pointer value 6023 ** <tr><td><b>sqlite3_value_text</b><td>→<td>UTF-8 TEXT value 6024 ** <tr><td><b>sqlite3_value_text16</b><td>→<td>UTF-16 TEXT value in 6025 ** the native byteorder 6026 ** <tr><td><b>sqlite3_value_text16be</b><td>→<td>UTF-16be TEXT value 6027 ** <tr><td><b>sqlite3_value_text16le</b><td>→<td>UTF-16le TEXT value 6028 ** <tr><td> <td> <td> 6029 ** <tr><td><b>sqlite3_value_bytes</b><td>→<td>Size of a BLOB 6030 ** or a UTF-8 TEXT in bytes 6031 ** <tr><td><b>sqlite3_value_bytes16 </b> 6032 ** <td>→ <td>Size of UTF-16 6033 ** TEXT in bytes 6034 ** <tr><td><b>sqlite3_value_type</b><td>→<td>Default 6035 ** datatype of the value 6036 ** <tr><td><b>sqlite3_value_numeric_type </b> 6037 ** <td>→ <td>Best numeric datatype of the value 6038 ** <tr><td><b>sqlite3_value_nochange </b> 6039 ** <td>→ <td>True if the column is unchanged in an UPDATE 6040 ** against a virtual table. 6041 ** <tr><td><b>sqlite3_value_frombind </b> 6042 ** <td>→ <td>True if value originated from a [bound parameter] 6043 ** </table></blockquote> 6044 ** 6045 ** <b>Details:</b> 6046 ** 6047 ** These routines extract type, size, and content information from 6048 ** [protected sqlite3_value] objects. Protected sqlite3_value objects 6049 ** are used to pass parameter information into the functions that 6050 ** implement [application-defined SQL functions] and [virtual tables]. 6051 ** 6052 ** These routines work only with [protected sqlite3_value] objects. 6053 ** Any attempt to use these routines on an [unprotected sqlite3_value] 6054 ** is not threadsafe. 6055 ** 6056 ** ^These routines work just like the corresponding [column access functions] 6057 ** except that these routines take a single [protected sqlite3_value] object 6058 ** pointer instead of a [sqlite3_stmt*] pointer and an integer column number. 6059 ** 6060 ** ^The sqlite3_value_text16() interface extracts a UTF-16 string 6061 ** in the native byte-order of the host machine. ^The 6062 ** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces 6063 ** extract UTF-16 strings as big-endian and little-endian respectively. 6064 ** 6065 ** ^If [sqlite3_value] object V was initialized 6066 ** using [sqlite3_bind_pointer(S,I,P,X,D)] or [sqlite3_result_pointer(C,P,X,D)] 6067 ** and if X and Y are strings that compare equal according to strcmp(X,Y), 6068 ** then sqlite3_value_pointer(V,Y) will return the pointer P. ^Otherwise, 6069 ** sqlite3_value_pointer(V,Y) returns a NULL. The sqlite3_bind_pointer() 6070 ** routine is part of the [pointer passing interface] added for SQLite 3.20.0. 6071 ** 6072 ** ^(The sqlite3_value_type(V) interface returns the 6073 ** [SQLITE_INTEGER | datatype code] for the initial datatype of the 6074 ** [sqlite3_value] object V. The returned value is one of [SQLITE_INTEGER], 6075 ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].)^ 6076 ** Other interfaces might change the datatype for an sqlite3_value object. 6077 ** For example, if the datatype is initially SQLITE_INTEGER and 6078 ** sqlite3_value_text(V) is called to extract a text value for that 6079 ** integer, then subsequent calls to sqlite3_value_type(V) might return 6080 ** SQLITE_TEXT. Whether or not a persistent internal datatype conversion 6081 ** occurs is undefined and may change from one release of SQLite to the next. 6082 ** 6083 ** ^(The sqlite3_value_numeric_type() interface attempts to apply 6084 ** numeric affinity to the value. This means that an attempt is 6085 ** made to convert the value to an integer or floating point. If 6086 ** such a conversion is possible without loss of information (in other 6087 ** words, if the value is a string that looks like a number) 6088 ** then the conversion is performed. Otherwise no conversion occurs. 6089 ** The [SQLITE_INTEGER | datatype] after conversion is returned.)^ 6090 ** 6091 ** ^Within the [xUpdate] method of a [virtual table], the 6092 ** sqlite3_value_nochange(X) interface returns true if and only if 6093 ** the column corresponding to X is unchanged by the UPDATE operation 6094 ** that the xUpdate method call was invoked to implement and if 6095 ** the prior [xColumn] method call that was invoked to extract 6096 ** the value for that column returned without setting a result (probably 6097 ** because it queried [sqlite3_vtab_nochange()] and found that the column 6098 ** was unchanging). ^Within an [xUpdate] method, any value for which 6099 ** sqlite3_value_nochange(X) is true will in all other respects appear 6100 ** to be a NULL value. If sqlite3_value_nochange(X) is invoked anywhere other 6101 ** than within an [xUpdate] method call for an UPDATE statement, then 6102 ** the return value is arbitrary and meaningless. 6103 ** 6104 ** ^The sqlite3_value_frombind(X) interface returns non-zero if the 6105 ** value X originated from one of the [sqlite3_bind_int|sqlite3_bind()] 6106 ** interfaces. ^If X comes from an SQL literal value, or a table column, 6107 ** or an expression, then sqlite3_value_frombind(X) returns zero. 6108 ** 6109 ** Please pay particular attention to the fact that the pointer returned 6110 ** from [sqlite3_value_blob()], [sqlite3_value_text()], or 6111 ** [sqlite3_value_text16()] can be invalidated by a subsequent call to 6112 ** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()], 6113 ** or [sqlite3_value_text16()]. 6114 ** 6115 ** These routines must be called from the same thread as 6116 ** the SQL function that supplied the [sqlite3_value*] parameters. 6117 ** 6118 ** As long as the input parameter is correct, these routines can only 6119 ** fail if an out-of-memory error occurs while trying to do a 6120 ** UTF8→UTF16 or UTF16→UTF8 conversion. 6121 ** If an out-of-memory error occurs, then the return value from these 6122 ** routines is the same as if the column had contained an SQL NULL value. 6123 ** If the input sqlite3_value was not obtained from [sqlite3_value_dup()], 6124 ** then valid SQL NULL returns can also be distinguished from 6125 ** out-of-memory errors after extracting the value 6126 ** by invoking the [sqlite3_errcode()] immediately after the suspicious 6127 ** return value is obtained and before any 6128 ** other SQLite interface is called on the same [database connection]. 6129 ** If the input sqlite3_value was obtained from sqlite3_value_dup() then 6130 ** it is disconnected from the database connection and so sqlite3_errcode() 6131 ** will not work. 6132 ** In that case, the only way to distinguish an out-of-memory 6133 ** condition from a true SQL NULL is to invoke sqlite3_value_type() on the 6134 ** input to see if it is NULL prior to trying to extract the value. 6135 */ 6136 SQLITE_API const void *sqlite3_value_blob(sqlite3_value*); 6137 SQLITE_API double sqlite3_value_double(sqlite3_value*); 6138 SQLITE_API int sqlite3_value_int(sqlite3_value*); 6139 SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*); 6140 SQLITE_API void *sqlite3_value_pointer(sqlite3_value*, const char*); 6141 SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*); 6142 SQLITE_API const void *sqlite3_value_text16(sqlite3_value*); 6143 SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*); 6144 SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*); 6145 SQLITE_API int sqlite3_value_bytes(sqlite3_value*); 6146 SQLITE_API int sqlite3_value_bytes16(sqlite3_value*); 6147 SQLITE_API int sqlite3_value_type(sqlite3_value*); 6148 SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*); 6149 SQLITE_API int sqlite3_value_nochange(sqlite3_value*); 6150 SQLITE_API int sqlite3_value_frombind(sqlite3_value*); 6151 6152 /* 6153 ** CAPI3REF: Report the internal text encoding state of an sqlite3_value object 6154 ** METHOD: sqlite3_value 6155 ** 6156 ** ^(The sqlite3_value_encoding(X) interface returns one of [SQLITE_UTF8], 6157 ** [SQLITE_UTF16BE], or [SQLITE_UTF16LE] according to the current text encoding 6158 ** of the value X, assuming that X has type TEXT.)^ If sqlite3_value_type(X) 6159 ** returns something other than SQLITE_TEXT, then the return value from 6160 ** sqlite3_value_encoding(X) is meaningless. ^Calls to 6161 ** [sqlite3_value_text(X)], [sqlite3_value_text16(X)], 6162 ** [sqlite3_value_text16be(X)], 6163 ** [sqlite3_value_text16le(X)], [sqlite3_value_bytes(X)], or 6164 ** [sqlite3_value_bytes16(X)] might change the encoding of the value X and 6165 ** thus change the return from subsequent calls to sqlite3_value_encoding(X). 6166 ** 6167 ** This routine is intended for used by applications that test and validate 6168 ** the SQLite implementation. This routine is inquiring about the opaque 6169 ** internal state of an [sqlite3_value] object. Ordinary applications should 6170 ** not need to know what the internal state of an sqlite3_value object is and 6171 ** hence should not need to use this interface. 6172 */ 6173 SQLITE_API int sqlite3_value_encoding(sqlite3_value*); 6174 6175 /* 6176 ** CAPI3REF: Finding The Subtype Of SQL Values 6177 ** METHOD: sqlite3_value 6178 ** 6179 ** The sqlite3_value_subtype(V) function returns the subtype for 6180 ** an [application-defined SQL function] argument V. The subtype 6181 ** information can be used to pass a limited amount of context from 6182 ** one SQL function to another. Use the [sqlite3_result_subtype()] 6183 ** routine to set the subtype for the return value of an SQL function. 6184 ** 6185 ** Every [application-defined SQL function] that invokes this interface 6186 ** should include the [SQLITE_SUBTYPE] property in the text 6187 ** encoding argument when the function is [sqlite3_create_function|registered]. 6188 ** If the [SQLITE_SUBTYPE] property is omitted, then sqlite3_value_subtype() 6189 ** might return zero instead of the upstream subtype in some corner cases. 6190 */ 6191 SQLITE_API unsigned int sqlite3_value_subtype(sqlite3_value*); 6192 6193 /* 6194 ** CAPI3REF: Copy And Free SQL Values 6195 ** METHOD: sqlite3_value 6196 ** 6197 ** ^The sqlite3_value_dup(V) interface makes a copy of the [sqlite3_value] 6198 ** object V and returns a pointer to that copy. ^The [sqlite3_value] returned 6199 ** is a [protected sqlite3_value] object even if the input is not. 6200 ** ^The sqlite3_value_dup(V) interface returns NULL if V is NULL or if a 6201 ** memory allocation fails. ^If V is a [pointer value], then the result 6202 ** of sqlite3_value_dup(V) is a NULL value. 6203 ** 6204 ** ^The sqlite3_value_free(V) interface frees an [sqlite3_value] object 6205 ** previously obtained from [sqlite3_value_dup()]. ^If V is a NULL pointer 6206 ** then sqlite3_value_free(V) is a harmless no-op. 6207 */ 6208 SQLITE_API sqlite3_value *sqlite3_value_dup(const sqlite3_value*); 6209 SQLITE_API void sqlite3_value_free(sqlite3_value*); 6210 6211 /* 6212 ** CAPI3REF: Obtain Aggregate Function Context 6213 ** METHOD: sqlite3_context 6214 ** 6215 ** Implementations of aggregate SQL functions use this 6216 ** routine to allocate memory for storing their state. 6217 ** 6218 ** ^The first time the sqlite3_aggregate_context(C,N) routine is called 6219 ** for a particular aggregate function, SQLite allocates 6220 ** N bytes of memory, zeroes out that memory, and returns a pointer 6221 ** to the new memory. ^On second and subsequent calls to 6222 ** sqlite3_aggregate_context() for the same aggregate function instance, 6223 ** the same buffer is returned. Sqlite3_aggregate_context() is normally 6224 ** called once for each invocation of the xStep callback and then one 6225 ** last time when the xFinal callback is invoked. ^(When no rows match 6226 ** an aggregate query, the xStep() callback of the aggregate function 6227 ** implementation is never called and xFinal() is called exactly once. 6228 ** In those cases, sqlite3_aggregate_context() might be called for the 6229 ** first time from within xFinal().)^ 6230 ** 6231 ** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer 6232 ** when first called if N is less than or equal to zero or if a memory 6233 ** allocation error occurs. 6234 ** 6235 ** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is 6236 ** determined by the N parameter on the first successful call. Changing the 6237 ** value of N in any subsequent call to sqlite3_aggregate_context() within 6238 ** the same aggregate function instance will not resize the memory 6239 ** allocation.)^ Within the xFinal callback, it is customary to set 6240 ** N=0 in calls to sqlite3_aggregate_context(C,N) so that no 6241 ** pointless memory allocations occur. 6242 ** 6243 ** ^SQLite automatically frees the memory allocated by 6244 ** sqlite3_aggregate_context() when the aggregate query concludes. 6245 ** 6246 ** The first parameter must be a copy of the 6247 ** [sqlite3_context | SQL function context] that is the first parameter 6248 ** to the xStep or xFinal callback routine that implements the aggregate 6249 ** function. 6250 ** 6251 ** This routine must be called from the same thread in which 6252 ** the aggregate SQL function is running. 6253 */ 6254 SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes); 6255 6256 /* 6257 ** CAPI3REF: User Data For Functions 6258 ** METHOD: sqlite3_context 6259 ** 6260 ** ^The sqlite3_user_data() interface returns a copy of 6261 ** the pointer that was the pUserData parameter (the 5th parameter) 6262 ** of the [sqlite3_create_function()] 6263 ** and [sqlite3_create_function16()] routines that originally 6264 ** registered the application defined function. 6265 ** 6266 ** This routine must be called from the same thread in which 6267 ** the application-defined function is running. 6268 */ 6269 SQLITE_API void *sqlite3_user_data(sqlite3_context*); 6270 6271 /* 6272 ** CAPI3REF: Database Connection For Functions 6273 ** METHOD: sqlite3_context 6274 ** 6275 ** ^The sqlite3_context_db_handle() interface returns a copy of 6276 ** the pointer to the [database connection] (the 1st parameter) 6277 ** of the [sqlite3_create_function()] 6278 ** and [sqlite3_create_function16()] routines that originally 6279 ** registered the application defined function. 6280 */ 6281 SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*); 6282 6283 /* 6284 ** CAPI3REF: Function Auxiliary Data 6285 ** METHOD: sqlite3_context 6286 ** 6287 ** These functions may be used by (non-aggregate) SQL functions to 6288 ** associate auxiliary data with argument values. If the same argument 6289 ** value is passed to multiple invocations of the same SQL function during 6290 ** query execution, under some circumstances the associated auxiliary data 6291 ** might be preserved. An example of where this might be useful is in a 6292 ** regular-expression matching function. The compiled version of the regular 6293 ** expression can be stored as auxiliary data associated with the pattern 6294 ** string. Then as long as the pattern string remains the same, 6295 ** the compiled regular expression can be reused on multiple 6296 ** invocations of the same function. 6297 ** 6298 ** ^The sqlite3_get_auxdata(C,N) interface returns a pointer to the auxiliary 6299 ** data associated by the sqlite3_set_auxdata(C,N,P,X) function with the 6300 ** Nth argument value to the application-defined function. ^N is zero 6301 ** for the left-most function argument. ^If there is no auxiliary data 6302 ** associated with the function argument, the sqlite3_get_auxdata(C,N) 6303 ** interface returns a NULL pointer. 6304 ** 6305 ** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as auxiliary data for the 6306 ** N-th argument of the application-defined function. ^Subsequent 6307 ** calls to sqlite3_get_auxdata(C,N) return P from the most recent 6308 ** sqlite3_set_auxdata(C,N,P,X) call if the auxiliary data is still valid or 6309 ** NULL if the auxiliary data has been discarded. 6310 ** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL, 6311 ** SQLite will invoke the destructor function X with parameter P exactly 6312 ** once, when the auxiliary data is discarded. 6313 ** SQLite is free to discard the auxiliary data at any time, including: <ul> 6314 ** <li> ^(when the corresponding function parameter changes)^, or 6315 ** <li> ^(when [sqlite3_reset()] or [sqlite3_finalize()] is called for the 6316 ** SQL statement)^, or 6317 ** <li> ^(when sqlite3_set_auxdata() is invoked again on the same 6318 ** parameter)^, or 6319 ** <li> ^(during the original sqlite3_set_auxdata() call when a memory 6320 ** allocation error occurs.)^ 6321 ** <li> ^(during the original sqlite3_set_auxdata() call if the function 6322 ** is evaluated during query planning instead of during query execution, 6323 ** as sometimes happens with [SQLITE_ENABLE_STAT4].)^ </ul> 6324 ** 6325 ** Note the last two bullets in particular. The destructor X in 6326 ** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the 6327 ** sqlite3_set_auxdata() interface even returns. Hence sqlite3_set_auxdata() 6328 ** should be called near the end of the function implementation and the 6329 ** function implementation should not make any use of P after 6330 ** sqlite3_set_auxdata() has been called. Furthermore, a call to 6331 ** sqlite3_get_auxdata() that occurs immediately after a corresponding call 6332 ** to sqlite3_set_auxdata() might still return NULL if an out-of-memory 6333 ** condition occurred during the sqlite3_set_auxdata() call or if the 6334 ** function is being evaluated during query planning rather than during 6335 ** query execution. 6336 ** 6337 ** ^(In practice, auxiliary data is preserved between function calls for 6338 ** function parameters that are compile-time constants, including literal 6339 ** values and [parameters] and expressions composed from the same.)^ 6340 ** 6341 ** The value of the N parameter to these interfaces should be non-negative. 6342 ** Future enhancements may make use of negative N values to define new 6343 ** kinds of function caching behavior. 6344 ** 6345 ** These routines must be called from the same thread in which 6346 ** the SQL function is running. 6347 ** 6348 ** See also: [sqlite3_get_clientdata()] and [sqlite3_set_clientdata()]. 6349 */ 6350 SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N); 6351 SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*)); 6352 6353 /* 6354 ** CAPI3REF: Database Connection Client Data 6355 ** METHOD: sqlite3 6356 ** 6357 ** These functions are used to associate one or more named pointers 6358 ** with a [database connection]. 6359 ** A call to sqlite3_set_clientdata(D,N,P,X) causes the pointer P 6360 ** to be attached to [database connection] D using name N. Subsequent 6361 ** calls to sqlite3_get_clientdata(D,N) will return a copy of pointer P 6362 ** or a NULL pointer if there were no prior calls to 6363 ** sqlite3_set_clientdata() with the same values of D and N. 6364 ** Names are compared using strcmp() and are thus case sensitive. 6365 ** It returns 0 on success and SQLITE_NOMEM on allocation failure. 6366 ** 6367 ** If P and X are both non-NULL, then the destructor X is invoked with 6368 ** argument P on the first of the following occurrences: 6369 ** <ul> 6370 ** <li> An out-of-memory error occurs during the call to 6371 ** sqlite3_set_clientdata() which attempts to register pointer P. 6372 ** <li> A subsequent call to sqlite3_set_clientdata(D,N,P,X) is made 6373 ** with the same D and N parameters. 6374 ** <li> The database connection closes. SQLite does not make any guarantees 6375 ** about the order in which destructors are called, only that all 6376 ** destructors will be called exactly once at some point during the 6377 ** database connection closing process. 6378 ** </ul> 6379 ** 6380 ** SQLite does not do anything with client data other than invoke 6381 ** destructors on the client data at the appropriate time. The intended 6382 ** use for client data is to provide a mechanism for wrapper libraries 6383 ** to store additional information about an SQLite database connection. 6384 ** 6385 ** There is no limit (other than available memory) on the number of different 6386 ** client data pointers (with different names) that can be attached to a 6387 ** single database connection. However, the current implementation stores 6388 ** the content on a linked list. Insert and retrieval performance will 6389 ** be proportional to the number of entries. The design use case, and 6390 ** the use case for which the implementation is optimized, is 6391 ** that an application will store only small number of client data names, 6392 ** typically just one or two. This interface is not intended to be a 6393 ** generalized key/value store for thousands or millions of keys. It 6394 ** will work for that, but performance might be disappointing. 6395 ** 6396 ** There is no way to enumerate the client data pointers 6397 ** associated with a database connection. The N parameter can be thought 6398 ** of as a secret key such that only code that knows the secret key is able 6399 ** to access the associated data. 6400 ** 6401 ** Security Warning: These interfaces should not be exposed in scripting 6402 ** languages or in other circumstances where it might be possible for an 6403 ** attacker to invoke them. Any agent that can invoke these interfaces 6404 ** can probably also take control of the process. 6405 ** 6406 ** Database connection client data is only available for SQLite 6407 ** version 3.44.0 ([dateof:3.44.0]) and later. 6408 ** 6409 ** See also: [sqlite3_set_auxdata()] and [sqlite3_get_auxdata()]. 6410 */ 6411 SQLITE_API void *sqlite3_get_clientdata(sqlite3*,const char*); 6412 SQLITE_API int sqlite3_set_clientdata(sqlite3*, const char*, void*, void(*)(void*)); 6413 6414 /* 6415 ** CAPI3REF: Constants Defining Special Destructor Behavior 6416 ** 6417 ** These are special values for the destructor that is passed in as the 6418 ** final argument to routines like [sqlite3_result_blob()]. ^If the destructor 6419 ** argument is SQLITE_STATIC, it means that the content pointer is constant 6420 ** and will never change. It does not need to be destroyed. ^The 6421 ** SQLITE_TRANSIENT value means that the content will likely change in 6422 ** the near future and that SQLite should make its own private copy of 6423 ** the content before returning. 6424 ** 6425 ** The typedef is necessary to work around problems in certain 6426 ** C++ compilers. 6427 */ 6428 typedef void (*sqlite3_destructor_type)(void*); 6429 #define SQLITE_STATIC ((sqlite3_destructor_type)0) 6430 #define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1) 6431 6432 /* 6433 ** CAPI3REF: Setting The Result Of An SQL Function 6434 ** METHOD: sqlite3_context 6435 ** 6436 ** These routines are used by the xFunc or xFinal callbacks that 6437 ** implement SQL functions and aggregates. See 6438 ** [sqlite3_create_function()] and [sqlite3_create_function16()] 6439 ** for additional information. 6440 ** 6441 ** These functions work very much like the [parameter binding] family of 6442 ** functions used to bind values to host parameters in prepared statements. 6443 ** Refer to the [SQL parameter] documentation for additional information. 6444 ** 6445 ** ^The sqlite3_result_blob() interface sets the result from 6446 ** an application-defined function to be the BLOB whose content is pointed 6447 ** to by the second parameter and which is N bytes long where N is the 6448 ** third parameter. 6449 ** 6450 ** ^The sqlite3_result_zeroblob(C,N) and sqlite3_result_zeroblob64(C,N) 6451 ** interfaces set the result of the application-defined function to be 6452 ** a BLOB containing all zero bytes and N bytes in size. 6453 ** 6454 ** ^The sqlite3_result_double() interface sets the result from 6455 ** an application-defined function to be a floating point value specified 6456 ** by its 2nd argument. 6457 ** 6458 ** ^The sqlite3_result_error() and sqlite3_result_error16() functions 6459 ** cause the implemented SQL function to throw an exception. 6460 ** ^SQLite uses the string pointed to by the 6461 ** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16() 6462 ** as the text of an error message. ^SQLite interprets the error 6463 ** message string from sqlite3_result_error() as UTF-8. ^SQLite 6464 ** interprets the string from sqlite3_result_error16() as UTF-16 using 6465 ** the same [byte-order determination rules] as [sqlite3_bind_text16()]. 6466 ** ^If the third parameter to sqlite3_result_error() 6467 ** or sqlite3_result_error16() is negative then SQLite takes as the error 6468 ** message all text up through the first zero character. 6469 ** ^If the third parameter to sqlite3_result_error() or 6470 ** sqlite3_result_error16() is non-negative then SQLite takes that many 6471 ** bytes (not characters) from the 2nd parameter as the error message. 6472 ** ^The sqlite3_result_error() and sqlite3_result_error16() 6473 ** routines make a private copy of the error message text before 6474 ** they return. Hence, the calling function can deallocate or 6475 ** modify the text after they return without harm. 6476 ** ^The sqlite3_result_error_code() function changes the error code 6477 ** returned by SQLite as a result of an error in a function. ^By default, 6478 ** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error() 6479 ** or sqlite3_result_error16() resets the error code to SQLITE_ERROR. 6480 ** 6481 ** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an 6482 ** error indicating that a string or BLOB is too long to represent. 6483 ** 6484 ** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an 6485 ** error indicating that a memory allocation failed. 6486 ** 6487 ** ^The sqlite3_result_int() interface sets the return value 6488 ** of the application-defined function to be the 32-bit signed integer 6489 ** value given in the 2nd argument. 6490 ** ^The sqlite3_result_int64() interface sets the return value 6491 ** of the application-defined function to be the 64-bit signed integer 6492 ** value given in the 2nd argument. 6493 ** 6494 ** ^The sqlite3_result_null() interface sets the return value 6495 ** of the application-defined function to be NULL. 6496 ** 6497 ** ^The sqlite3_result_text(), sqlite3_result_text16(), 6498 ** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces 6499 ** set the return value of the application-defined function to be 6500 ** a text string which is represented as UTF-8, UTF-16 native byte order, 6501 ** UTF-16 little endian, or UTF-16 big endian, respectively. 6502 ** ^The sqlite3_result_text64(C,Z,N,D,E) interface sets the return value of an 6503 ** application-defined function to be a text string in an encoding 6504 ** specified the E parameter, which must be one 6505 ** of [SQLITE_UTF8], [SQLITE_UTF8_ZT], [SQLITE_UTF16], [SQLITE_UTF16BE], 6506 ** or [SQLITE_UTF16LE]. ^The special value [SQLITE_UTF8_ZT] means that 6507 ** the result text is both UTF-8 and zero-terminated. In other words, 6508 ** SQLITE_UTF8_ZT means that the Z array holds at least N+1 bytes and that 6509 ** the Z[N] is zero. 6510 ** ^SQLite takes the text result from the application from 6511 ** the 2nd parameter of the sqlite3_result_text* interfaces. 6512 ** ^If the 3rd parameter to any of the sqlite3_result_text* interfaces 6513 ** other than sqlite3_result_text64() is negative, then SQLite computes 6514 ** the string length itself by searching the 2nd parameter for the first 6515 ** zero character. 6516 ** ^If the 3rd parameter to the sqlite3_result_text* interfaces 6517 ** is non-negative, then as many bytes (not characters) of the text 6518 ** pointed to by the 2nd parameter are taken as the application-defined 6519 ** function result. If the 3rd parameter is non-negative, then it 6520 ** must be the byte offset into the string where the NUL terminator would 6521 ** appear if the string were NUL terminated. If any NUL characters occur 6522 ** in the string at a byte offset that is less than the value of the 3rd 6523 ** parameter, then the resulting string will contain embedded NULs and the 6524 ** result of expressions operating on strings with embedded NULs is undefined. 6525 ** ^If the 4th parameter to the sqlite3_result_text* interfaces 6526 ** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that 6527 ** function as the destructor on the text or BLOB result when it has 6528 ** finished using that result. 6529 ** ^If the 4th parameter to the sqlite3_result_text* interfaces or to 6530 ** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite 6531 ** assumes that the text or BLOB result is in constant space and does not 6532 ** copy the content of the parameter nor call a destructor on the content 6533 ** when it has finished using that result. 6534 ** ^If the 4th parameter to the sqlite3_result_text* interfaces 6535 ** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT 6536 ** then SQLite makes a copy of the result into space obtained 6537 ** from [sqlite3_malloc()] before it returns. 6538 ** 6539 ** ^For the sqlite3_result_text16(), sqlite3_result_text16le(), and 6540 ** sqlite3_result_text16be() routines, and for sqlite3_result_text64() 6541 ** when the encoding is not UTF8, if the input UTF16 begins with a 6542 ** byte-order mark (BOM, U+FEFF) then the BOM is removed from the 6543 ** string and the rest of the string is interpreted according to the 6544 ** byte-order specified by the BOM. ^The byte-order specified by 6545 ** the BOM at the beginning of the text overrides the byte-order 6546 ** specified by the interface procedure. ^So, for example, if 6547 ** sqlite3_result_text16le() is invoked with text that begins 6548 ** with bytes 0xfe, 0xff (a big-endian byte-order mark) then the 6549 ** first two bytes of input are skipped and the remaining input 6550 ** is interpreted as UTF16BE text. 6551 ** 6552 ** ^For UTF16 input text to the sqlite3_result_text16(), 6553 ** sqlite3_result_text16be(), sqlite3_result_text16le(), and 6554 ** sqlite3_result_text64() routines, if the text contains invalid 6555 ** UTF16 characters, the invalid characters might be converted 6556 ** into the unicode replacement character, U+FFFD. 6557 ** 6558 ** ^The sqlite3_result_value() interface sets the result of 6559 ** the application-defined function to be a copy of the 6560 ** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The 6561 ** sqlite3_result_value() interface makes a copy of the [sqlite3_value] 6562 ** so that the [sqlite3_value] specified in the parameter may change or 6563 ** be deallocated after sqlite3_result_value() returns without harm. 6564 ** ^A [protected sqlite3_value] object may always be used where an 6565 ** [unprotected sqlite3_value] object is required, so either 6566 ** kind of [sqlite3_value] object can be used with this interface. 6567 ** 6568 ** ^The sqlite3_result_pointer(C,P,T,D) interface sets the result to an 6569 ** SQL NULL value, just like [sqlite3_result_null(C)], except that it 6570 ** also associates the host-language pointer P or type T with that 6571 ** NULL value such that the pointer can be retrieved within an 6572 ** [application-defined SQL function] using [sqlite3_value_pointer()]. 6573 ** ^If the D parameter is not NULL, then it is a pointer to a destructor 6574 ** for the P parameter. ^SQLite invokes D with P as its only argument 6575 ** when SQLite is finished with P. The T parameter should be a static 6576 ** string and preferably a string literal. The sqlite3_result_pointer() 6577 ** routine is part of the [pointer passing interface] added for SQLite 3.20.0. 6578 ** 6579 ** If these routines are called from within a different thread 6580 ** than the one containing the application-defined function that received 6581 ** the [sqlite3_context] pointer, the results are undefined. 6582 */ 6583 SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*)); 6584 SQLITE_API void sqlite3_result_blob64(sqlite3_context*,const void*, 6585 sqlite3_uint64,void(*)(void*)); 6586 SQLITE_API void sqlite3_result_double(sqlite3_context*, double); 6587 SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int); 6588 SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int); 6589 SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*); 6590 SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*); 6591 SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int); 6592 SQLITE_API void sqlite3_result_int(sqlite3_context*, int); 6593 SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64); 6594 SQLITE_API void sqlite3_result_null(sqlite3_context*); 6595 SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*)); 6596 SQLITE_API void sqlite3_result_text64(sqlite3_context*, const char *z, sqlite3_uint64 n, 6597 void(*)(void*), unsigned char encoding); 6598 SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*)); 6599 SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*)); 6600 SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*)); 6601 SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*); 6602 SQLITE_API void sqlite3_result_pointer(sqlite3_context*, void*,const char*,void(*)(void*)); 6603 SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n); 6604 SQLITE_API int sqlite3_result_zeroblob64(sqlite3_context*, sqlite3_uint64 n); 6605 6606 6607 /* 6608 ** CAPI3REF: Setting The Subtype Of An SQL Function 6609 ** METHOD: sqlite3_context 6610 ** 6611 ** The sqlite3_result_subtype(C,T) function causes the subtype of 6612 ** the result from the [application-defined SQL function] with 6613 ** [sqlite3_context] C to be the value T. Only the lower 8 bits 6614 ** of the subtype T are preserved in current versions of SQLite; 6615 ** higher order bits are discarded. 6616 ** The number of subtype bytes preserved by SQLite might increase 6617 ** in future releases of SQLite. 6618 ** 6619 ** Every [application-defined SQL function] that invokes this interface 6620 ** should include the [SQLITE_RESULT_SUBTYPE] property in its 6621 ** text encoding argument when the SQL function is 6622 ** [sqlite3_create_function|registered]. If the [SQLITE_RESULT_SUBTYPE] 6623 ** property is omitted from the function that invokes sqlite3_result_subtype(), 6624 ** then in some cases the sqlite3_result_subtype() might fail to set 6625 ** the result subtype. 6626 ** 6627 ** If SQLite is compiled with -DSQLITE_STRICT_SUBTYPE=1, then any 6628 ** SQL function that invokes the sqlite3_result_subtype() interface 6629 ** and that does not have the SQLITE_RESULT_SUBTYPE property will raise 6630 ** an error. Future versions of SQLite might enable -DSQLITE_STRICT_SUBTYPE=1 6631 ** by default. 6632 */ 6633 SQLITE_API void sqlite3_result_subtype(sqlite3_context*,unsigned int); 6634 6635 /* 6636 ** CAPI3REF: Define New Collating Sequences 6637 ** METHOD: sqlite3 6638 ** 6639 ** ^These functions add, remove, or modify a [collation] associated 6640 ** with the [database connection] specified as the first argument. 6641 ** 6642 ** ^The name of the collation is a UTF-8 string 6643 ** for sqlite3_create_collation() and sqlite3_create_collation_v2() 6644 ** and a UTF-16 string in native byte order for sqlite3_create_collation16(). 6645 ** ^Collation names that compare equal according to [sqlite3_strnicmp()] are 6646 ** considered to be the same name. 6647 ** 6648 ** ^(The third argument (eTextRep) must be one of the constants: 6649 ** <ul> 6650 ** <li> [SQLITE_UTF8], 6651 ** <li> [SQLITE_UTF16LE], 6652 ** <li> [SQLITE_UTF16BE], 6653 ** <li> [SQLITE_UTF16], or 6654 ** <li> [SQLITE_UTF16_ALIGNED]. 6655 ** </ul>)^ 6656 ** ^The eTextRep argument determines the encoding of strings passed 6657 ** to the collating function callback, xCompare. 6658 ** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep 6659 ** force strings to be UTF16 with native byte order. 6660 ** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin 6661 ** on an even byte address. 6662 ** 6663 ** ^The fourth argument, pArg, is an application data pointer that is passed 6664 ** through as the first argument to the collating function callback. 6665 ** 6666 ** ^The fifth argument, xCompare, is a pointer to the collating function. 6667 ** ^Multiple collating functions can be registered using the same name but 6668 ** with different eTextRep parameters and SQLite will use whichever 6669 ** function requires the least amount of data transformation. 6670 ** ^If the xCompare argument is NULL then the collating function is 6671 ** deleted. ^When all collating functions having the same name are deleted, 6672 ** that collation is no longer usable. 6673 ** 6674 ** ^The collating function callback is invoked with a copy of the pArg 6675 ** application data pointer and with two strings in the encoding specified 6676 ** by the eTextRep argument. The two integer parameters to the collating 6677 ** function callback are the length of the two strings, in bytes. The collating 6678 ** function must return an integer that is negative, zero, or positive 6679 ** if the first string is less than, equal to, or greater than the second, 6680 ** respectively. A collating function must always return the same answer 6681 ** given the same inputs. If two or more collating functions are registered 6682 ** to the same collation name (using different eTextRep values) then all 6683 ** must give an equivalent answer when invoked with equivalent strings. 6684 ** The collating function must obey the following properties for all 6685 ** strings A, B, and C: 6686 ** 6687 ** <ol> 6688 ** <li> If A==B then B==A. 6689 ** <li> If A==B and B==C then A==C. 6690 ** <li> If A<B THEN B>A. 6691 ** <li> If A<B and B<C then A<C. 6692 ** </ol> 6693 ** 6694 ** If a collating function fails any of the above constraints and that 6695 ** collating function is registered and used, then the behavior of SQLite 6696 ** is undefined. 6697 ** 6698 ** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation() 6699 ** with the addition that the xDestroy callback is invoked on pArg when 6700 ** the collating function is deleted. 6701 ** ^Collating functions are deleted when they are overridden by later 6702 ** calls to the collation creation functions or when the 6703 ** [database connection] is closed using [sqlite3_close()]. 6704 ** 6705 ** ^The xDestroy callback is <u>not</u> called if the 6706 ** sqlite3_create_collation_v2() function fails. Applications that invoke 6707 ** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should 6708 ** check the return code and dispose of the application data pointer 6709 ** themselves rather than expecting SQLite to deal with it for them. 6710 ** This is different from every other SQLite interface. The inconsistency 6711 ** is unfortunate but cannot be changed without breaking backwards 6712 ** compatibility. 6713 ** 6714 ** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()]. 6715 */ 6716 SQLITE_API int sqlite3_create_collation( 6717 sqlite3*, 6718 const char *zName, 6719 int eTextRep, 6720 void *pArg, 6721 int(*xCompare)(void*,int,const void*,int,const void*) 6722 ); 6723 SQLITE_API int sqlite3_create_collation_v2( 6724 sqlite3*, 6725 const char *zName, 6726 int eTextRep, 6727 void *pArg, 6728 int(*xCompare)(void*,int,const void*,int,const void*), 6729 void(*xDestroy)(void*) 6730 ); 6731 SQLITE_API int sqlite3_create_collation16( 6732 sqlite3*, 6733 const void *zName, 6734 int eTextRep, 6735 void *pArg, 6736 int(*xCompare)(void*,int,const void*,int,const void*) 6737 ); 6738 6739 /* 6740 ** CAPI3REF: Collation Needed Callbacks 6741 ** METHOD: sqlite3 6742 ** 6743 ** ^To avoid having to register all collation sequences before a database 6744 ** can be used, a single callback function may be registered with the 6745 ** [database connection] to be invoked whenever an undefined collation 6746 ** sequence is required. 6747 ** 6748 ** ^If the function is registered using the sqlite3_collation_needed() API, 6749 ** then it is passed the names of undefined collation sequences as strings 6750 ** encoded in UTF-8. ^If sqlite3_collation_needed16() is used, 6751 ** the names are passed as UTF-16 in machine native byte order. 6752 ** ^A call to either function replaces the existing collation-needed callback. 6753 ** 6754 ** ^(When the callback is invoked, the first argument passed is a copy 6755 ** of the second argument to sqlite3_collation_needed() or 6756 ** sqlite3_collation_needed16(). The second argument is the database 6757 ** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE], 6758 ** or [SQLITE_UTF16LE], indicating the most desirable form of the collation 6759 ** sequence function required. The fourth parameter is the name of the 6760 ** required collation sequence.)^ 6761 ** 6762 ** The callback function should register the desired collation using 6763 ** [sqlite3_create_collation()], [sqlite3_create_collation16()], or 6764 ** [sqlite3_create_collation_v2()]. 6765 */ 6766 SQLITE_API int sqlite3_collation_needed( 6767 sqlite3*, 6768 void*, 6769 void(*)(void*,sqlite3*,int eTextRep,const char*) 6770 ); 6771 SQLITE_API int sqlite3_collation_needed16( 6772 sqlite3*, 6773 void*, 6774 void(*)(void*,sqlite3*,int eTextRep,const void*) 6775 ); 6776 6777 #ifdef SQLITE_ENABLE_CEROD 6778 /* 6779 ** Specify the activation key for a CEROD database. Unless 6780 ** activated, none of the CEROD routines will work. 6781 */ 6782 SQLITE_API void sqlite3_activate_cerod( 6783 const char *zPassPhrase /* Activation phrase */ 6784 ); 6785 #endif 6786 6787 /* 6788 ** CAPI3REF: Suspend Execution For A Short Time 6789 ** 6790 ** The sqlite3_sleep() function causes the current thread to suspend execution 6791 ** for at least a number of milliseconds specified in its parameter. 6792 ** 6793 ** If the operating system does not support sleep requests with 6794 ** millisecond time resolution, then the time will be rounded up to 6795 ** the nearest second. The number of milliseconds of sleep actually 6796 ** requested from the operating system is returned. 6797 ** 6798 ** ^SQLite implements this interface by calling the xSleep() 6799 ** method of the default [sqlite3_vfs] object. If the xSleep() method 6800 ** of the default VFS is not implemented correctly, or not implemented at 6801 ** all, then the behavior of sqlite3_sleep() may deviate from the description 6802 ** in the previous paragraphs. 6803 ** 6804 ** If a negative argument is passed to sqlite3_sleep() the results vary by 6805 ** VFS and operating system. Some system treat a negative argument as an 6806 ** instruction to sleep forever. Others understand it to mean do not sleep 6807 ** at all. ^In SQLite version 3.42.0 and later, a negative 6808 ** argument passed into sqlite3_sleep() is changed to zero before it is relayed 6809 ** down into the xSleep method of the VFS. 6810 */ 6811 SQLITE_API int sqlite3_sleep(int); 6812 6813 /* 6814 ** CAPI3REF: Name Of The Folder Holding Temporary Files 6815 ** 6816 ** ^(If this global variable is made to point to a string which is 6817 ** the name of a folder (a.k.a. directory), then all temporary files 6818 ** created by SQLite when using a built-in [sqlite3_vfs | VFS] 6819 ** will be placed in that directory.)^ ^If this variable 6820 ** is a NULL pointer, then SQLite performs a search for an appropriate 6821 ** temporary file directory. 6822 ** 6823 ** Applications are strongly discouraged from using this global variable. 6824 ** It is required to set a temporary folder on Windows Runtime (WinRT). 6825 ** But for all other platforms, it is highly recommended that applications 6826 ** neither read nor write this variable. This global variable is a relic 6827 ** that exists for backwards compatibility of legacy applications and should 6828 ** be avoided in new projects. 6829 ** 6830 ** It is not safe to read or modify this variable in more than one 6831 ** thread at a time. It is not safe to read or modify this variable 6832 ** if a [database connection] is being used at the same time in a separate 6833 ** thread. 6834 ** It is intended that this variable be set once 6835 ** as part of process initialization and before any SQLite interface 6836 ** routines have been called and that this variable remain unchanged 6837 ** thereafter. 6838 ** 6839 ** ^The [temp_store_directory pragma] may modify this variable and cause 6840 ** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore, 6841 ** the [temp_store_directory pragma] always assumes that any string 6842 ** that this variable points to is held in memory obtained from 6843 ** [sqlite3_malloc] and the pragma may attempt to free that memory 6844 ** using [sqlite3_free]. 6845 ** Hence, if this variable is modified directly, either it should be 6846 ** made NULL or made to point to memory obtained from [sqlite3_malloc] 6847 ** or else the use of the [temp_store_directory pragma] should be avoided. 6848 ** Except when requested by the [temp_store_directory pragma], SQLite 6849 ** does not free the memory that sqlite3_temp_directory points to. If 6850 ** the application wants that memory to be freed, it must do 6851 ** so itself, taking care to only do so after all [database connection] 6852 ** objects have been destroyed. 6853 ** 6854 ** <b>Note to Windows Runtime users:</b> The temporary directory must be set 6855 ** prior to calling [sqlite3_open] or [sqlite3_open_v2]. Otherwise, various 6856 ** features that require the use of temporary files may fail. Here is an 6857 ** example of how to do this using C++ with the Windows Runtime: 6858 ** 6859 ** <blockquote><pre> 6860 ** LPCWSTR zPath = Windows::Storage::ApplicationData::Current-> 6861 ** TemporaryFolder->Path->Data(); 6862 ** char zPathBuf[MAX_PATH + 1]; 6863 ** memset(zPathBuf, 0, sizeof(zPathBuf)); 6864 ** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf), 6865 ** NULL, NULL); 6866 ** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf); 6867 ** </pre></blockquote> 6868 */ 6869 SQLITE_API SQLITE_EXTERN char *sqlite3_temp_directory; 6870 6871 /* 6872 ** CAPI3REF: Name Of The Folder Holding Database Files 6873 ** 6874 ** ^(If this global variable is made to point to a string which is 6875 ** the name of a folder (a.k.a. directory), then all database files 6876 ** specified with a relative pathname and created or accessed by 6877 ** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed 6878 ** to be relative to that directory.)^ ^If this variable is a NULL 6879 ** pointer, then SQLite assumes that all database files specified 6880 ** with a relative pathname are relative to the current directory 6881 ** for the process. Only the windows VFS makes use of this global 6882 ** variable; it is ignored by the unix VFS. 6883 ** 6884 ** Changing the value of this variable while a database connection is 6885 ** open can result in a corrupt database. 6886 ** 6887 ** It is not safe to read or modify this variable in more than one 6888 ** thread at a time. It is not safe to read or modify this variable 6889 ** if a [database connection] is being used at the same time in a separate 6890 ** thread. 6891 ** It is intended that this variable be set once 6892 ** as part of process initialization and before any SQLite interface 6893 ** routines have been called and that this variable remain unchanged 6894 ** thereafter. 6895 ** 6896 ** ^The [data_store_directory pragma] may modify this variable and cause 6897 ** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore, 6898 ** the [data_store_directory pragma] always assumes that any string 6899 ** that this variable points to is held in memory obtained from 6900 ** [sqlite3_malloc] and the pragma may attempt to free that memory 6901 ** using [sqlite3_free]. 6902 ** Hence, if this variable is modified directly, either it should be 6903 ** made NULL or made to point to memory obtained from [sqlite3_malloc] 6904 ** or else the use of the [data_store_directory pragma] should be avoided. 6905 */ 6906 SQLITE_API SQLITE_EXTERN char *sqlite3_data_directory; 6907 6908 /* 6909 ** CAPI3REF: Win32 Specific Interface 6910 ** 6911 ** These interfaces are available only on Windows. The 6912 ** [sqlite3_win32_set_directory] interface is used to set the value associated 6913 ** with the [sqlite3_temp_directory] or [sqlite3_data_directory] variable, to 6914 ** zValue, depending on the value of the type parameter. The zValue parameter 6915 ** should be NULL to cause the previous value to be freed via [sqlite3_free]; 6916 ** a non-NULL value will be copied into memory obtained from [sqlite3_malloc] 6917 ** prior to being used. The [sqlite3_win32_set_directory] interface returns 6918 ** [SQLITE_OK] to indicate success, [SQLITE_ERROR] if the type is unsupported, 6919 ** or [SQLITE_NOMEM] if memory could not be allocated. The value of the 6920 ** [sqlite3_data_directory] variable is intended to act as a replacement for 6921 ** the current directory on the sub-platforms of Win32 where that concept is 6922 ** not present, e.g. WinRT and UWP. The [sqlite3_win32_set_directory8] and 6923 ** [sqlite3_win32_set_directory16] interfaces behave exactly the same as the 6924 ** sqlite3_win32_set_directory interface except the string parameter must be 6925 ** UTF-8 or UTF-16, respectively. 6926 */ 6927 SQLITE_API int sqlite3_win32_set_directory( 6928 unsigned long type, /* Identifier for directory being set or reset */ 6929 void *zValue /* New value for directory being set or reset */ 6930 ); 6931 SQLITE_API int sqlite3_win32_set_directory8(unsigned long type, const char *zValue); 6932 SQLITE_API int sqlite3_win32_set_directory16(unsigned long type, const void *zValue); 6933 6934 /* 6935 ** CAPI3REF: Win32 Directory Types 6936 ** 6937 ** These macros are only available on Windows. They define the allowed values 6938 ** for the type argument to the [sqlite3_win32_set_directory] interface. 6939 */ 6940 #define SQLITE_WIN32_DATA_DIRECTORY_TYPE 1 6941 #define SQLITE_WIN32_TEMP_DIRECTORY_TYPE 2 6942 6943 /* 6944 ** CAPI3REF: Test For Auto-Commit Mode 6945 ** KEYWORDS: {autocommit mode} 6946 ** METHOD: sqlite3 6947 ** 6948 ** ^The sqlite3_get_autocommit() interface returns non-zero or 6949 ** zero if the given database connection is or is not in autocommit mode, 6950 ** respectively. ^Autocommit mode is on by default. 6951 ** ^Autocommit mode is disabled by a [BEGIN] statement. 6952 ** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK]. 6953 ** 6954 ** If certain kinds of errors occur on a statement within a multi-statement 6955 ** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR], 6956 ** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the 6957 ** transaction might be rolled back automatically. The only way to 6958 ** find out whether SQLite automatically rolled back the transaction after 6959 ** an error is to use this function. 6960 ** 6961 ** If another thread changes the autocommit status of the database 6962 ** connection while this routine is running, then the return value 6963 ** is undefined. 6964 */ 6965 SQLITE_API int sqlite3_get_autocommit(sqlite3*); 6966 6967 /* 6968 ** CAPI3REF: Find The Database Handle Of A Prepared Statement 6969 ** METHOD: sqlite3_stmt 6970 ** 6971 ** ^The sqlite3_db_handle interface returns the [database connection] handle 6972 ** to which a [prepared statement] belongs. ^The [database connection] 6973 ** returned by sqlite3_db_handle is the same [database connection] 6974 ** that was the first argument 6975 ** to the [sqlite3_prepare_v2()] call (or its variants) that was used to 6976 ** create the statement in the first place. 6977 */ 6978 SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*); 6979 6980 /* 6981 ** CAPI3REF: Return The Schema Name For A Database Connection 6982 ** METHOD: sqlite3 6983 ** 6984 ** ^The sqlite3_db_name(D,N) interface returns a pointer to the schema name 6985 ** for the N-th database on database connection D, or a NULL pointer if N is 6986 ** out of range. An N value of 0 means the main database file. An N of 1 is 6987 ** the "temp" schema. Larger values of N correspond to various ATTACH-ed 6988 ** databases. 6989 ** 6990 ** Space to hold the string that is returned by sqlite3_db_name() is managed 6991 ** by SQLite itself. The string might be deallocated by any operation that 6992 ** changes the schema, including [ATTACH] or [DETACH] or calls to 6993 ** [sqlite3_serialize()] or [sqlite3_deserialize()], even operations that 6994 ** occur on a different thread. Applications that need to 6995 ** remember the string long-term should make their own copy. Applications that 6996 ** are accessing the same database connection simultaneously on multiple 6997 ** threads should mutex-protect calls to this API and should make their own 6998 ** private copy of the result prior to releasing the mutex. 6999 */ 7000 SQLITE_API const char *sqlite3_db_name(sqlite3 *db, int N); 7001 7002 /* 7003 ** CAPI3REF: Return The Filename For A Database Connection 7004 ** METHOD: sqlite3 7005 ** 7006 ** ^The sqlite3_db_filename(D,N) interface returns a pointer to the filename 7007 ** associated with database N of connection D. 7008 ** ^If there is no attached database N on the database 7009 ** connection D, or if database N is a temporary or in-memory database, then 7010 ** this function will return either a NULL pointer or an empty string. 7011 ** 7012 ** ^The string value returned by this routine is owned and managed by 7013 ** the database connection. ^The value will be valid until the database N 7014 ** is [DETACH]-ed or until the database connection closes. 7015 ** 7016 ** ^The filename returned by this function is the output of the 7017 ** xFullPathname method of the [VFS]. ^In other words, the filename 7018 ** will be an absolute pathname, even if the filename used 7019 ** to open the database originally was a URI or relative pathname. 7020 ** 7021 ** If the filename pointer returned by this routine is not NULL, then it 7022 ** can be used as the filename input parameter to these routines: 7023 ** <ul> 7024 ** <li> [sqlite3_uri_parameter()] 7025 ** <li> [sqlite3_uri_boolean()] 7026 ** <li> [sqlite3_uri_int64()] 7027 ** <li> [sqlite3_filename_database()] 7028 ** <li> [sqlite3_filename_journal()] 7029 ** <li> [sqlite3_filename_wal()] 7030 ** </ul> 7031 */ 7032 SQLITE_API sqlite3_filename sqlite3_db_filename(sqlite3 *db, const char *zDbName); 7033 7034 /* 7035 ** CAPI3REF: Determine if a database is read-only 7036 ** METHOD: sqlite3 7037 ** 7038 ** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N 7039 ** of connection D is read-only, 0 if it is read/write, or -1 if N is not 7040 ** the name of a database on connection D. 7041 */ 7042 SQLITE_API int sqlite3_db_readonly(sqlite3 *db, const char *zDbName); 7043 7044 /* 7045 ** CAPI3REF: Determine the transaction state of a database 7046 ** METHOD: sqlite3 7047 ** 7048 ** ^The sqlite3_txn_state(D,S) interface returns the current 7049 ** [transaction state] of schema S in database connection D. ^If S is NULL, 7050 ** then the highest transaction state of any schema on database connection D 7051 ** is returned. Transaction states are (in order of lowest to highest): 7052 ** <ol> 7053 ** <li value="0"> SQLITE_TXN_NONE 7054 ** <li value="1"> SQLITE_TXN_READ 7055 ** <li value="2"> SQLITE_TXN_WRITE 7056 ** </ol> 7057 ** ^If the S argument to sqlite3_txn_state(D,S) is not the name of 7058 ** a valid schema, then -1 is returned. 7059 */ 7060 SQLITE_API int sqlite3_txn_state(sqlite3*,const char *zSchema); 7061 7062 /* 7063 ** CAPI3REF: Allowed return values from sqlite3_txn_state() 7064 ** KEYWORDS: {transaction state} 7065 ** 7066 ** These constants define the current transaction state of a database file. 7067 ** ^The [sqlite3_txn_state(D,S)] interface returns one of these 7068 ** constants in order to describe the transaction state of schema S 7069 ** in [database connection] D. 7070 ** 7071 ** <dl> 7072 ** [[SQLITE_TXN_NONE]] <dt>SQLITE_TXN_NONE</dt> 7073 ** <dd>The SQLITE_TXN_NONE state means that no transaction is currently 7074 ** pending.</dd> 7075 ** 7076 ** [[SQLITE_TXN_READ]] <dt>SQLITE_TXN_READ</dt> 7077 ** <dd>The SQLITE_TXN_READ state means that the database is currently 7078 ** in a read transaction. Content has been read from the database file 7079 ** but nothing in the database file has changed. The transaction state 7080 ** will be advanced to SQLITE_TXN_WRITE if any changes occur and there are 7081 ** no other conflicting concurrent write transactions. The transaction 7082 ** state will revert to SQLITE_TXN_NONE following a [ROLLBACK] or 7083 ** [COMMIT].</dd> 7084 ** 7085 ** [[SQLITE_TXN_WRITE]] <dt>SQLITE_TXN_WRITE</dt> 7086 ** <dd>The SQLITE_TXN_WRITE state means that the database is currently 7087 ** in a write transaction. Content has been written to the database file 7088 ** but has not yet committed. The transaction state will change to 7089 ** SQLITE_TXN_NONE at the next [ROLLBACK] or [COMMIT].</dd> 7090 */ 7091 #define SQLITE_TXN_NONE 0 7092 #define SQLITE_TXN_READ 1 7093 #define SQLITE_TXN_WRITE 2 7094 7095 /* 7096 ** CAPI3REF: Find the next prepared statement 7097 ** METHOD: sqlite3 7098 ** 7099 ** ^This interface returns a pointer to the next [prepared statement] after 7100 ** pStmt associated with the [database connection] pDb. ^If pStmt is NULL 7101 ** then this interface returns a pointer to the first prepared statement 7102 ** associated with the database connection pDb. ^If no prepared statement 7103 ** satisfies the conditions of this routine, it returns NULL. 7104 ** 7105 ** The [database connection] pointer D in a call to 7106 ** [sqlite3_next_stmt(D,S)] must refer to an open database 7107 ** connection and in particular must not be a NULL pointer. 7108 */ 7109 SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt); 7110 7111 /* 7112 ** CAPI3REF: Commit And Rollback Notification Callbacks 7113 ** METHOD: sqlite3 7114 ** 7115 ** ^The sqlite3_commit_hook() interface registers a callback 7116 ** function to be invoked whenever a transaction is [COMMIT | committed]. 7117 ** ^Any callback set by a previous call to sqlite3_commit_hook() 7118 ** for the same database connection is overridden. 7119 ** ^The sqlite3_rollback_hook() interface registers a callback 7120 ** function to be invoked whenever a transaction is [ROLLBACK | rolled back]. 7121 ** ^Any callback set by a previous call to sqlite3_rollback_hook() 7122 ** for the same database connection is overridden. 7123 ** ^The pArg argument is passed through to the callback. 7124 ** ^If the callback on a commit hook function returns non-zero, 7125 ** then the commit is converted into a rollback. 7126 ** 7127 ** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions 7128 ** return the P argument from the previous call of the same function 7129 ** on the same [database connection] D, or NULL for 7130 ** the first call for each function on D. 7131 ** 7132 ** The commit and rollback hook callbacks are not reentrant. 7133 ** The callback implementation must not do anything that will modify 7134 ** the database connection that invoked the callback. Any actions 7135 ** to modify the database connection must be deferred until after the 7136 ** completion of the [sqlite3_step()] call that triggered the commit 7137 ** or rollback hook in the first place. 7138 ** Note that running any other SQL statements, including SELECT statements, 7139 ** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify 7140 ** the database connections for the meaning of "modify" in this paragraph. 7141 ** 7142 ** ^Registering a NULL function disables the callback. 7143 ** 7144 ** ^When the commit hook callback routine returns zero, the [COMMIT] 7145 ** operation is allowed to continue normally. ^If the commit hook 7146 ** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK]. 7147 ** ^The rollback hook is invoked on a rollback that results from a commit 7148 ** hook returning non-zero, just as it would be with any other rollback. 7149 ** 7150 ** ^For the purposes of this API, a transaction is said to have been 7151 ** rolled back if an explicit "ROLLBACK" statement is executed, or 7152 ** an error or constraint causes an implicit rollback to occur. 7153 ** ^The rollback callback is not invoked if a transaction is 7154 ** automatically rolled back because the database connection is closed. 7155 ** 7156 ** See also the [sqlite3_update_hook()] interface. 7157 */ 7158 SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*); 7159 SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*); 7160 7161 /* 7162 ** CAPI3REF: Autovacuum Compaction Amount Callback 7163 ** METHOD: sqlite3 7164 ** 7165 ** ^The sqlite3_autovacuum_pages(D,C,P,X) interface registers a callback 7166 ** function C that is invoked prior to each autovacuum of the database 7167 ** file. ^The callback is passed a copy of the generic data pointer (P), 7168 ** the schema-name of the attached database that is being autovacuumed, 7169 ** the size of the database file in pages, the number of free pages, 7170 ** and the number of bytes per page, respectively. The callback should 7171 ** return the number of free pages that should be removed by the 7172 ** autovacuum. ^If the callback returns zero, then no autovacuum happens. 7173 ** ^If the value returned is greater than or equal to the number of 7174 ** free pages, then a complete autovacuum happens. 7175 ** 7176 ** <p>^If there are multiple ATTACH-ed database files that are being 7177 ** modified as part of a transaction commit, then the autovacuum pages 7178 ** callback is invoked separately for each file. 7179 ** 7180 ** <p><b>The callback is not reentrant.</b> The callback function should 7181 ** not attempt to invoke any other SQLite interface. If it does, bad 7182 ** things may happen, including segmentation faults and corrupt database 7183 ** files. The callback function should be a simple function that 7184 ** does some arithmetic on its input parameters and returns a result. 7185 ** 7186 ** ^The X parameter to sqlite3_autovacuum_pages(D,C,P,X) is an optional 7187 ** destructor for the P parameter. ^If X is not NULL, then X(P) is 7188 ** invoked whenever the database connection closes or when the callback 7189 ** is overwritten by another invocation of sqlite3_autovacuum_pages(). 7190 ** 7191 ** <p>^There is only one autovacuum pages callback per database connection. 7192 ** ^Each call to the sqlite3_autovacuum_pages() interface overrides all 7193 ** previous invocations for that database connection. ^If the callback 7194 ** argument (C) to sqlite3_autovacuum_pages(D,C,P,X) is a NULL pointer, 7195 ** then the autovacuum steps callback is canceled. The return value 7196 ** from sqlite3_autovacuum_pages() is normally SQLITE_OK, but might 7197 ** be some other error code if something goes wrong. The current 7198 ** implementation will only return SQLITE_OK or SQLITE_MISUSE, but other 7199 ** return codes might be added in future releases. 7200 ** 7201 ** <p>If no autovacuum pages callback is specified (the usual case) or 7202 ** a NULL pointer is provided for the callback, 7203 ** then the default behavior is to vacuum all free pages. So, in other 7204 ** words, the default behavior is the same as if the callback function 7205 ** were something like this: 7206 ** 7207 ** <blockquote><pre> 7208 ** unsigned int demonstration_autovac_pages_callback( 7209 ** void *pClientData, 7210 ** const char *zSchema, 7211 ** unsigned int nDbPage, 7212 ** unsigned int nFreePage, 7213 ** unsigned int nBytePerPage 7214 ** ){ 7215 ** return nFreePage; 7216 ** } 7217 ** </pre></blockquote> 7218 */ 7219 SQLITE_API int sqlite3_autovacuum_pages( 7220 sqlite3 *db, 7221 unsigned int(*)(void*,const char*,unsigned int,unsigned int,unsigned int), 7222 void*, 7223 void(*)(void*) 7224 ); 7225 7226 7227 /* 7228 ** CAPI3REF: Data Change Notification Callbacks 7229 ** METHOD: sqlite3 7230 ** 7231 ** ^The sqlite3_update_hook() interface registers a callback function 7232 ** with the [database connection] identified by the first argument 7233 ** to be invoked whenever a row is updated, inserted or deleted in 7234 ** a [rowid table]. 7235 ** ^Any callback set by a previous call to this function 7236 ** for the same database connection is overridden. 7237 ** 7238 ** ^The second argument is a pointer to the function to invoke when a 7239 ** row is updated, inserted or deleted in a rowid table. 7240 ** ^The update hook is disabled by invoking sqlite3_update_hook() 7241 ** with a NULL pointer as the second parameter. 7242 ** ^The first argument to the callback is a copy of the third argument 7243 ** to sqlite3_update_hook(). 7244 ** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE], 7245 ** or [SQLITE_UPDATE], depending on the operation that caused the callback 7246 ** to be invoked. 7247 ** ^The third and fourth arguments to the callback contain pointers to the 7248 ** database and table name containing the affected row. 7249 ** ^The final callback parameter is the [rowid] of the row. 7250 ** ^In the case of an update, this is the [rowid] after the update takes place. 7251 ** 7252 ** ^(The update hook is not invoked when internal system tables are 7253 ** modified (i.e. sqlite_sequence).)^ 7254 ** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified. 7255 ** 7256 ** ^In the current implementation, the update hook 7257 ** is not invoked when conflicting rows are deleted because of an 7258 ** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook 7259 ** invoked when rows are deleted using the [truncate optimization]. 7260 ** The exceptions defined in this paragraph might change in a future 7261 ** release of SQLite. 7262 ** 7263 ** Whether the update hook is invoked before or after the 7264 ** corresponding change is currently unspecified and may differ 7265 ** depending on the type of change. Do not rely on the order of the 7266 ** hook call with regards to the final result of the operation which 7267 ** triggers the hook. 7268 ** 7269 ** The update hook implementation must not do anything that will modify 7270 ** the database connection that invoked the update hook. Any actions 7271 ** to modify the database connection must be deferred until after the 7272 ** completion of the [sqlite3_step()] call that triggered the update hook. 7273 ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their 7274 ** database connections for the meaning of "modify" in this paragraph. 7275 ** 7276 ** ^The sqlite3_update_hook(D,C,P) function 7277 ** returns the P argument from the previous call 7278 ** on the same [database connection] D, or NULL for 7279 ** the first call on D. 7280 ** 7281 ** See also the [sqlite3_commit_hook()], [sqlite3_rollback_hook()], 7282 ** and [sqlite3_preupdate_hook()] interfaces. 7283 */ 7284 SQLITE_API void *sqlite3_update_hook( 7285 sqlite3*, 7286 void(*)(void *,int ,char const *,char const *,sqlite3_int64), 7287 void* 7288 ); 7289 7290 /* 7291 ** CAPI3REF: Enable Or Disable Shared Pager Cache 7292 ** 7293 ** ^(This routine enables or disables the sharing of the database cache 7294 ** and schema data structures between [database connection | connections] 7295 ** to the same database. Sharing is enabled if the argument is true 7296 ** and disabled if the argument is false.)^ 7297 ** 7298 ** This interface is omitted if SQLite is compiled with 7299 ** [-DSQLITE_OMIT_SHARED_CACHE]. The [-DSQLITE_OMIT_SHARED_CACHE] 7300 ** compile-time option is recommended because the 7301 ** [use of shared cache mode is discouraged]. 7302 ** 7303 ** ^Cache sharing is enabled and disabled for an entire process. 7304 ** This is a change as of SQLite [version 3.5.0] ([dateof:3.5.0]). 7305 ** In prior versions of SQLite, 7306 ** sharing was enabled or disabled for each thread separately. 7307 ** 7308 ** ^(The cache sharing mode set by this interface effects all subsequent 7309 ** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()]. 7310 ** Existing database connections continue to use the sharing mode 7311 ** that was in effect at the time they were opened.)^ 7312 ** 7313 ** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled 7314 ** successfully. An [error code] is returned otherwise.)^ 7315 ** 7316 ** ^Shared cache is disabled by default. It is recommended that it stay 7317 ** that way. In other words, do not use this routine. This interface 7318 ** continues to be provided for historical compatibility, but its use is 7319 ** discouraged. Any use of shared cache is discouraged. If shared cache 7320 ** must be used, it is recommended that shared cache only be enabled for 7321 ** individual database connections using the [sqlite3_open_v2()] interface 7322 ** with the [SQLITE_OPEN_SHAREDCACHE] flag. 7323 ** 7324 ** Note: This method is disabled on MacOS X 10.7 and iOS version 5.0 7325 ** and will always return SQLITE_MISUSE. On those systems, 7326 ** shared cache mode should be enabled per-database connection via 7327 ** [sqlite3_open_v2()] with [SQLITE_OPEN_SHAREDCACHE]. 7328 ** 7329 ** This interface is threadsafe on processors where writing a 7330 ** 32-bit integer is atomic. 7331 ** 7332 ** See Also: [SQLite Shared-Cache Mode] 7333 */ 7334 SQLITE_API int sqlite3_enable_shared_cache(int); 7335 7336 /* 7337 ** CAPI3REF: Attempt To Free Heap Memory 7338 ** 7339 ** ^The sqlite3_release_memory() interface attempts to free N bytes 7340 ** of heap memory by deallocating non-essential memory allocations 7341 ** held by the database library. Memory used to cache database 7342 ** pages to improve performance is an example of non-essential memory. 7343 ** ^sqlite3_release_memory() returns the number of bytes actually freed, 7344 ** which might be more or less than the amount requested. 7345 ** ^The sqlite3_release_memory() routine is a no-op returning zero 7346 ** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT]. 7347 ** 7348 ** See also: [sqlite3_db_release_memory()] 7349 */ 7350 SQLITE_API int sqlite3_release_memory(int); 7351 7352 /* 7353 ** CAPI3REF: Free Memory Used By A Database Connection 7354 ** METHOD: sqlite3 7355 ** 7356 ** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap 7357 ** memory as possible from database connection D. Unlike the 7358 ** [sqlite3_release_memory()] interface, this interface is in effect even 7359 ** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is 7360 ** omitted. 7361 ** 7362 ** See also: [sqlite3_release_memory()] 7363 */ 7364 SQLITE_API int sqlite3_db_release_memory(sqlite3*); 7365 7366 /* 7367 ** CAPI3REF: Impose A Limit On Heap Size 7368 ** 7369 ** These interfaces impose limits on the amount of heap memory that will be 7370 ** used by all database connections within a single process. 7371 ** 7372 ** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the 7373 ** soft limit on the amount of heap memory that may be allocated by SQLite. 7374 ** ^SQLite strives to keep heap memory utilization below the soft heap 7375 ** limit by reducing the number of pages held in the page cache 7376 ** as heap memory usages approaches the limit. 7377 ** ^The soft heap limit is "soft" because even though SQLite strives to stay 7378 ** below the limit, it will exceed the limit rather than generate 7379 ** an [SQLITE_NOMEM] error. In other words, the soft heap limit 7380 ** is advisory only. 7381 ** 7382 ** ^The sqlite3_hard_heap_limit64(N) interface sets a hard upper bound of 7383 ** N bytes on the amount of memory that will be allocated. ^The 7384 ** sqlite3_hard_heap_limit64(N) interface is similar to 7385 ** sqlite3_soft_heap_limit64(N) except that memory allocations will fail 7386 ** when the hard heap limit is reached. 7387 ** 7388 ** ^The return value from both sqlite3_soft_heap_limit64() and 7389 ** sqlite3_hard_heap_limit64() is the size of 7390 ** the heap limit prior to the call, or negative in the case of an 7391 ** error. ^If the argument N is negative 7392 ** then no change is made to the heap limit. Hence, the current 7393 ** size of heap limits can be determined by invoking 7394 ** sqlite3_soft_heap_limit64(-1) or sqlite3_hard_heap_limit(-1). 7395 ** 7396 ** ^Setting the heap limits to zero disables the heap limiter mechanism. 7397 ** 7398 ** ^The soft heap limit may not be greater than the hard heap limit. 7399 ** ^If the hard heap limit is enabled and if sqlite3_soft_heap_limit(N) 7400 ** is invoked with a value of N that is greater than the hard heap limit, 7401 ** the soft heap limit is set to the value of the hard heap limit. 7402 ** ^The soft heap limit is automatically enabled whenever the hard heap 7403 ** limit is enabled. ^When sqlite3_hard_heap_limit64(N) is invoked and 7404 ** the soft heap limit is outside the range of 1..N, then the soft heap 7405 ** limit is set to N. ^Invoking sqlite3_soft_heap_limit64(0) when the 7406 ** hard heap limit is enabled makes the soft heap limit equal to the 7407 ** hard heap limit. 7408 ** 7409 ** The memory allocation limits can also be adjusted using 7410 ** [PRAGMA soft_heap_limit] and [PRAGMA hard_heap_limit]. 7411 ** 7412 ** ^(The heap limits are not enforced in the current implementation 7413 ** if one or more of following conditions are true: 7414 ** 7415 ** <ul> 7416 ** <li> The limit value is set to zero. 7417 ** <li> Memory accounting is disabled using a combination of the 7418 ** [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and 7419 ** the [SQLITE_DEFAULT_MEMSTATUS] compile-time option. 7420 ** <li> An alternative page cache implementation is specified using 7421 ** [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...). 7422 ** <li> The page cache allocates from its own memory pool supplied 7423 ** by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than 7424 ** from the heap. 7425 ** </ul>)^ 7426 ** 7427 ** The circumstances under which SQLite will enforce the heap limits may 7428 ** change in future releases of SQLite. 7429 */ 7430 SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N); 7431 SQLITE_API sqlite3_int64 sqlite3_hard_heap_limit64(sqlite3_int64 N); 7432 7433 /* 7434 ** CAPI3REF: Deprecated Soft Heap Limit Interface 7435 ** DEPRECATED 7436 ** 7437 ** This is a deprecated version of the [sqlite3_soft_heap_limit64()] 7438 ** interface. This routine is provided for historical compatibility 7439 ** only. All new applications should use the 7440 ** [sqlite3_soft_heap_limit64()] interface rather than this one. 7441 */ 7442 SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N); 7443 7444 7445 /* 7446 ** CAPI3REF: Extract Metadata About A Column Of A Table 7447 ** METHOD: sqlite3 7448 ** 7449 ** ^(The sqlite3_table_column_metadata(X,D,T,C,....) routine returns 7450 ** information about column C of table T in database D 7451 ** on [database connection] X.)^ ^The sqlite3_table_column_metadata() 7452 ** interface returns SQLITE_OK and fills in the non-NULL pointers in 7453 ** the final five arguments with appropriate values if the specified 7454 ** column exists. ^The sqlite3_table_column_metadata() interface returns 7455 ** SQLITE_ERROR if the specified column does not exist. 7456 ** ^If the column-name parameter to sqlite3_table_column_metadata() is a 7457 ** NULL pointer, then this routine simply checks for the existence of the 7458 ** table and returns SQLITE_OK if the table exists and SQLITE_ERROR if it 7459 ** does not. If the table name parameter T in a call to 7460 ** sqlite3_table_column_metadata(X,D,T,C,...) is NULL then the result is 7461 ** undefined behavior. 7462 ** 7463 ** ^The column is identified by the second, third and fourth parameters to 7464 ** this function. ^(The second parameter is either the name of the database 7465 ** (i.e. "main", "temp", or an attached database) containing the specified 7466 ** table or NULL.)^ ^If it is NULL, then all attached databases are searched 7467 ** for the table using the same algorithm used by the database engine to 7468 ** resolve unqualified table references. 7469 ** 7470 ** ^The third and fourth parameters to this function are the table and column 7471 ** name of the desired column, respectively. 7472 ** 7473 ** ^Metadata is returned by writing to the memory locations passed as the 5th 7474 ** and subsequent parameters to this function. ^Any of these arguments may be 7475 ** NULL, in which case the corresponding element of metadata is omitted. 7476 ** 7477 ** ^(<blockquote> 7478 ** <table border="1"> 7479 ** <tr><th> Parameter <th> Output<br>Type <th> Description 7480 ** 7481 ** <tr><td> 5th <td> const char* <td> Data type 7482 ** <tr><td> 6th <td> const char* <td> Name of default collation sequence 7483 ** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint 7484 ** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY 7485 ** <tr><td> 9th <td> int <td> True if column is [AUTOINCREMENT] 7486 ** </table> 7487 ** </blockquote>)^ 7488 ** 7489 ** ^The memory pointed to by the character pointers returned for the 7490 ** declaration type and collation sequence is valid until the next 7491 ** call to any SQLite API function. 7492 ** 7493 ** ^If the specified table is actually a view, an [error code] is returned. 7494 ** 7495 ** ^If the specified column is "rowid", "oid" or "_rowid_" and the table 7496 ** is not a [WITHOUT ROWID] table and an 7497 ** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output 7498 ** parameters are set for the explicitly declared column. ^(If there is no 7499 ** [INTEGER PRIMARY KEY] column, then the outputs 7500 ** for the [rowid] are set as follows: 7501 ** 7502 ** <pre> 7503 ** data type: "INTEGER" 7504 ** collation sequence: "BINARY" 7505 ** not null: 0 7506 ** primary key: 1 7507 ** auto increment: 0 7508 ** </pre>)^ 7509 ** 7510 ** ^This function causes all database schemas to be read from disk and 7511 ** parsed, if that has not already been done, and returns an error if 7512 ** any errors are encountered while loading the schema. 7513 */ 7514 SQLITE_API int sqlite3_table_column_metadata( 7515 sqlite3 *db, /* Connection handle */ 7516 const char *zDbName, /* Database name or NULL */ 7517 const char *zTableName, /* Table name */ 7518 const char *zColumnName, /* Column name */ 7519 char const **pzDataType, /* OUTPUT: Declared data type */ 7520 char const **pzCollSeq, /* OUTPUT: Collation sequence name */ 7521 int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */ 7522 int *pPrimaryKey, /* OUTPUT: True if column part of PK */ 7523 int *pAutoinc /* OUTPUT: True if column is auto-increment */ 7524 ); 7525 7526 /* 7527 ** CAPI3REF: Load An Extension 7528 ** METHOD: sqlite3 7529 ** 7530 ** ^This interface loads an SQLite extension library from the named file. 7531 ** 7532 ** ^The sqlite3_load_extension() interface attempts to load an 7533 ** [SQLite extension] library contained in the file zFile. If 7534 ** the file cannot be loaded directly, attempts are made to load 7535 ** with various operating-system specific filename extensions added. 7536 ** So for example, if "samplelib" cannot be loaded, then names like 7537 ** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might 7538 ** be tried also. 7539 ** 7540 ** ^The entry point is zProc. 7541 ** ^(zProc may be 0, in which case SQLite will try to come up with an 7542 ** entry point name on its own. It first tries "sqlite3_extension_init". 7543 ** If that does not work, it tries names of the form "sqlite3_X_init" 7544 ** where X consists of the lower-case equivalent of all ASCII alphabetic 7545 ** characters or all ASCII alphanumeric characters in the filename from 7546 ** the last "/" to the first following "." and omitting any initial "lib".)^ 7547 ** ^The sqlite3_load_extension() interface returns 7548 ** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong. 7549 ** ^If an error occurs and pzErrMsg is not 0, then the 7550 ** [sqlite3_load_extension()] interface shall attempt to 7551 ** fill *pzErrMsg with error message text stored in memory 7552 ** obtained from [sqlite3_malloc()]. The calling function 7553 ** should free this memory by calling [sqlite3_free()]. 7554 ** 7555 ** ^Extension loading must be enabled using 7556 ** [sqlite3_enable_load_extension()] or 7557 ** [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],1,NULL) 7558 ** prior to calling this API, 7559 ** otherwise an error will be returned. 7560 ** 7561 ** <b>Security warning:</b> It is recommended that the 7562 ** [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method be used to enable only this 7563 ** interface. The use of the [sqlite3_enable_load_extension()] interface 7564 ** should be avoided. This will keep the SQL function [load_extension()] 7565 ** disabled and prevent SQL injections from giving attackers 7566 ** access to extension loading capabilities. 7567 ** 7568 ** See also the [load_extension() SQL function]. 7569 */ 7570 SQLITE_API int sqlite3_load_extension( 7571 sqlite3 *db, /* Load the extension into this database connection */ 7572 const char *zFile, /* Name of the shared library containing extension */ 7573 const char *zProc, /* Entry point. Derived from zFile if 0 */ 7574 char **pzErrMsg /* Put error message here if not 0 */ 7575 ); 7576 7577 /* 7578 ** CAPI3REF: Enable Or Disable Extension Loading 7579 ** METHOD: sqlite3 7580 ** 7581 ** ^So as not to open security holes in older applications that are 7582 ** unprepared to deal with [extension loading], and as a means of disabling 7583 ** [extension loading] while evaluating user-entered SQL, the following API 7584 ** is provided to turn the [sqlite3_load_extension()] mechanism on and off. 7585 ** 7586 ** ^Extension loading is off by default. 7587 ** ^Call the sqlite3_enable_load_extension() routine with onoff==1 7588 ** to turn extension loading on and call it with onoff==0 to turn 7589 ** it back off again. 7590 ** 7591 ** ^This interface enables or disables both the C-API 7592 ** [sqlite3_load_extension()] and the SQL function [load_extension()]. 7593 ** ^(Use [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],..) 7594 ** to enable or disable only the C-API.)^ 7595 ** 7596 ** <b>Security warning:</b> It is recommended that extension loading 7597 ** be enabled using the [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method 7598 ** rather than this interface, so the [load_extension()] SQL function 7599 ** remains disabled. This will prevent SQL injections from giving attackers 7600 ** access to extension loading capabilities. 7601 */ 7602 SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff); 7603 7604 /* 7605 ** CAPI3REF: Automatically Load Statically Linked Extensions 7606 ** 7607 ** ^This interface causes the xEntryPoint() function to be invoked for 7608 ** each new [database connection] that is created. The idea here is that 7609 ** xEntryPoint() is the entry point for a statically linked [SQLite extension] 7610 ** that is to be automatically loaded into all new database connections. 7611 ** 7612 ** ^(Even though the function prototype shows that xEntryPoint() takes 7613 ** no arguments and returns void, SQLite invokes xEntryPoint() with three 7614 ** arguments and expects an integer result as if the signature of the 7615 ** entry point were as follows: 7616 ** 7617 ** <blockquote><pre> 7618 ** int xEntryPoint( 7619 ** sqlite3 *db, 7620 ** char **pzErrMsg, 7621 ** const struct sqlite3_api_routines *pThunk 7622 ** ); 7623 ** </pre></blockquote>)^ 7624 ** 7625 ** If the xEntryPoint routine encounters an error, it should make *pzErrMsg 7626 ** point to an appropriate error message (obtained from [sqlite3_mprintf()]) 7627 ** and return an appropriate [error code]. ^SQLite ensures that *pzErrMsg 7628 ** is NULL before calling the xEntryPoint(). ^SQLite will invoke 7629 ** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns. ^If any 7630 ** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()], 7631 ** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail. 7632 ** 7633 ** ^Calling sqlite3_auto_extension(X) with an entry point X that is already 7634 ** on the list of automatic extensions is a harmless no-op. ^No entry point 7635 ** will be called more than once for each database connection that is opened. 7636 ** 7637 ** See also: [sqlite3_reset_auto_extension()] 7638 ** and [sqlite3_cancel_auto_extension()] 7639 */ 7640 SQLITE_API int sqlite3_auto_extension(void(*xEntryPoint)(void)); 7641 7642 /* 7643 ** CAPI3REF: Cancel Automatic Extension Loading 7644 ** 7645 ** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the 7646 ** initialization routine X that was registered using a prior call to 7647 ** [sqlite3_auto_extension(X)]. ^The [sqlite3_cancel_auto_extension(X)] 7648 ** routine returns 1 if initialization routine X was successfully 7649 ** unregistered and it returns 0 if X was not on the list of initialization 7650 ** routines. 7651 */ 7652 SQLITE_API int sqlite3_cancel_auto_extension(void(*xEntryPoint)(void)); 7653 7654 /* 7655 ** CAPI3REF: Reset Automatic Extension Loading 7656 ** 7657 ** ^This interface disables all automatic extensions previously 7658 ** registered using [sqlite3_auto_extension()]. 7659 */ 7660 SQLITE_API void sqlite3_reset_auto_extension(void); 7661 7662 /* 7663 ** Structures used by the virtual table interface 7664 */ 7665 typedef struct sqlite3_vtab sqlite3_vtab; 7666 typedef struct sqlite3_index_info sqlite3_index_info; 7667 typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor; 7668 typedef struct sqlite3_module sqlite3_module; 7669 7670 /* 7671 ** CAPI3REF: Virtual Table Object 7672 ** KEYWORDS: sqlite3_module {virtual table module} 7673 ** 7674 ** This structure, sometimes called a "virtual table module", 7675 ** defines the implementation of a [virtual table]. 7676 ** This structure consists mostly of methods for the module. 7677 ** 7678 ** ^A virtual table module is created by filling in a persistent 7679 ** instance of this structure and passing a pointer to that instance 7680 ** to [sqlite3_create_module()] or [sqlite3_create_module_v2()]. 7681 ** ^The registration remains valid until it is replaced by a different 7682 ** module or until the [database connection] closes. The content 7683 ** of this structure must not change while it is registered with 7684 ** any database connection. 7685 */ 7686 struct sqlite3_module { 7687 int iVersion; 7688 int (*xCreate)(sqlite3*, void *pAux, 7689 int argc, const char *const*argv, 7690 sqlite3_vtab **ppVTab, char**); 7691 int (*xConnect)(sqlite3*, void *pAux, 7692 int argc, const char *const*argv, 7693 sqlite3_vtab **ppVTab, char**); 7694 int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*); 7695 int (*xDisconnect)(sqlite3_vtab *pVTab); 7696 int (*xDestroy)(sqlite3_vtab *pVTab); 7697 int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor); 7698 int (*xClose)(sqlite3_vtab_cursor*); 7699 int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr, 7700 int argc, sqlite3_value **argv); 7701 int (*xNext)(sqlite3_vtab_cursor*); 7702 int (*xEof)(sqlite3_vtab_cursor*); 7703 int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int); 7704 int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid); 7705 int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *); 7706 int (*xBegin)(sqlite3_vtab *pVTab); 7707 int (*xSync)(sqlite3_vtab *pVTab); 7708 int (*xCommit)(sqlite3_vtab *pVTab); 7709 int (*xRollback)(sqlite3_vtab *pVTab); 7710 int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName, 7711 void (**pxFunc)(sqlite3_context*,int,sqlite3_value**), 7712 void **ppArg); 7713 int (*xRename)(sqlite3_vtab *pVtab, const char *zNew); 7714 /* The methods above are in version 1 of the sqlite_module object. Those 7715 ** below are for version 2 and greater. */ 7716 int (*xSavepoint)(sqlite3_vtab *pVTab, int); 7717 int (*xRelease)(sqlite3_vtab *pVTab, int); 7718 int (*xRollbackTo)(sqlite3_vtab *pVTab, int); 7719 /* The methods above are in versions 1 and 2 of the sqlite_module object. 7720 ** Those below are for version 3 and greater. */ 7721 int (*xShadowName)(const char*); 7722 /* The methods above are in versions 1 through 3 of the sqlite_module object. 7723 ** Those below are for version 4 and greater. */ 7724 int (*xIntegrity)(sqlite3_vtab *pVTab, const char *zSchema, 7725 const char *zTabName, int mFlags, char **pzErr); 7726 }; 7727 7728 /* 7729 ** CAPI3REF: Virtual Table Indexing Information 7730 ** KEYWORDS: sqlite3_index_info 7731 ** 7732 ** The sqlite3_index_info structure and its substructures is used as part 7733 ** of the [virtual table] interface to 7734 ** pass information into and receive the reply from the [xBestIndex] 7735 ** method of a [virtual table module]. The fields under **Inputs** are the 7736 ** inputs to xBestIndex and are read-only. xBestIndex inserts its 7737 ** results into the **Outputs** fields. 7738 ** 7739 ** ^(The aConstraint[] array records WHERE clause constraints of the form: 7740 ** 7741 ** <blockquote>column OP expr</blockquote> 7742 ** 7743 ** where OP is =, <, <=, >, or >=.)^ ^(The particular operator is 7744 ** stored in aConstraint[].op using one of the 7745 ** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^ 7746 ** ^(The index of the column is stored in 7747 ** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the 7748 ** expr on the right-hand side can be evaluated (and thus the constraint 7749 ** is usable) and false if it cannot.)^ 7750 ** 7751 ** ^The optimizer automatically inverts terms of the form "expr OP column" 7752 ** and makes other simplifications to the WHERE clause in an attempt to 7753 ** get as many WHERE clause terms into the form shown above as possible. 7754 ** ^The aConstraint[] array only reports WHERE clause terms that are 7755 ** relevant to the particular virtual table being queried. 7756 ** 7757 ** ^Information about the ORDER BY clause is stored in aOrderBy[]. 7758 ** ^Each term of aOrderBy records a column of the ORDER BY clause. 7759 ** 7760 ** The colUsed field indicates which columns of the virtual table may be 7761 ** required by the current scan. Virtual table columns are numbered from 7762 ** zero in the order in which they appear within the CREATE TABLE statement 7763 ** passed to sqlite3_declare_vtab(). For the first 63 columns (columns 0-62), 7764 ** the corresponding bit is set within the colUsed mask if the column may be 7765 ** required by SQLite. If the table has at least 64 columns and any column 7766 ** to the right of the first 63 is required, then bit 63 of colUsed is also 7767 ** set. In other words, column iCol may be required if the expression 7768 ** (colUsed & ((sqlite3_uint64)1 << (iCol>=63 ? 63 : iCol))) evaluates to 7769 ** non-zero. 7770 ** 7771 ** The [xBestIndex] method must fill aConstraintUsage[] with information 7772 ** about what parameters to pass to xFilter. ^If argvIndex>0 then 7773 ** the right-hand side of the corresponding aConstraint[] is evaluated 7774 ** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit 7775 ** is true, then the constraint is assumed to be fully handled by the 7776 ** virtual table and might not be checked again by the byte code.)^ ^(The 7777 ** aConstraintUsage[].omit flag is an optimization hint. When the omit flag 7778 ** is left in its default setting of false, the constraint will always be 7779 ** checked separately in byte code. If the omit flag is changed to true, then 7780 ** the constraint may or may not be checked in byte code. In other words, 7781 ** when the omit flag is true there is no guarantee that the constraint will 7782 ** not be checked again using byte code.)^ 7783 ** 7784 ** ^The idxNum and idxStr values are recorded and passed into the 7785 ** [xFilter] method. 7786 ** ^[sqlite3_free()] is used to free idxStr if and only if 7787 ** needToFreeIdxStr is true. 7788 ** 7789 ** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in 7790 ** the correct order to satisfy the ORDER BY clause so that no separate 7791 ** sorting step is required. 7792 ** 7793 ** ^The estimatedCost value is an estimate of the cost of a particular 7794 ** strategy. A cost of N indicates that the cost of the strategy is similar 7795 ** to a linear scan of an SQLite table with N rows. A cost of log(N) 7796 ** indicates that the expense of the operation is similar to that of a 7797 ** binary search on a unique indexed field of an SQLite table with N rows. 7798 ** 7799 ** ^The estimatedRows value is an estimate of the number of rows that 7800 ** will be returned by the strategy. 7801 ** 7802 ** The xBestIndex method may optionally populate the idxFlags field with a 7803 ** mask of SQLITE_INDEX_SCAN_* flags. One such flag is 7804 ** [SQLITE_INDEX_SCAN_HEX], which if set causes the [EXPLAIN QUERY PLAN] 7805 ** output to show the idxNum as hex instead of as decimal. Another flag is 7806 ** SQLITE_INDEX_SCAN_UNIQUE, which if set indicates that the query plan will 7807 ** return at most one row. 7808 ** 7809 ** Additionally, if xBestIndex sets the SQLITE_INDEX_SCAN_UNIQUE flag, then 7810 ** SQLite also assumes that if a call to the xUpdate() method is made as 7811 ** part of the same statement to delete or update a virtual table row and the 7812 ** implementation returns SQLITE_CONSTRAINT, then there is no need to rollback 7813 ** any database changes. In other words, if the xUpdate() returns 7814 ** SQLITE_CONSTRAINT, the database contents must be exactly as they were 7815 ** before xUpdate was called. By contrast, if SQLITE_INDEX_SCAN_UNIQUE is not 7816 ** set and xUpdate returns SQLITE_CONSTRAINT, any database changes made by 7817 ** the xUpdate method are automatically rolled back by SQLite. 7818 ** 7819 ** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info 7820 ** structure for SQLite [version 3.8.2] ([dateof:3.8.2]). 7821 ** If a virtual table extension is 7822 ** used with an SQLite version earlier than 3.8.2, the results of attempting 7823 ** to read or write the estimatedRows field are undefined (but are likely 7824 ** to include crashing the application). The estimatedRows field should 7825 ** therefore only be used if [sqlite3_libversion_number()] returns a 7826 ** value greater than or equal to 3008002. Similarly, the idxFlags field 7827 ** was added for [version 3.9.0] ([dateof:3.9.0]). 7828 ** It may therefore only be used if 7829 ** sqlite3_libversion_number() returns a value greater than or equal to 7830 ** 3009000. 7831 */ 7832 struct sqlite3_index_info { 7833 /* Inputs */ 7834 int nConstraint; /* Number of entries in aConstraint */ 7835 struct sqlite3_index_constraint { 7836 int iColumn; /* Column constrained. -1 for ROWID */ 7837 unsigned char op; /* Constraint operator */ 7838 unsigned char usable; /* True if this constraint is usable */ 7839 int iTermOffset; /* Used internally - xBestIndex should ignore */ 7840 } *aConstraint; /* Table of WHERE clause constraints */ 7841 int nOrderBy; /* Number of terms in the ORDER BY clause */ 7842 struct sqlite3_index_orderby { 7843 int iColumn; /* Column number */ 7844 unsigned char desc; /* True for DESC. False for ASC. */ 7845 } *aOrderBy; /* The ORDER BY clause */ 7846 /* Outputs */ 7847 struct sqlite3_index_constraint_usage { 7848 int argvIndex; /* if >0, constraint is part of argv to xFilter */ 7849 unsigned char omit; /* Do not code a test for this constraint */ 7850 } *aConstraintUsage; 7851 int idxNum; /* Number used to identify the index */ 7852 char *idxStr; /* String, possibly obtained from sqlite3_malloc */ 7853 int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */ 7854 int orderByConsumed; /* True if output is already ordered */ 7855 double estimatedCost; /* Estimated cost of using this index */ 7856 /* Fields below are only available in SQLite 3.8.2 and later */ 7857 sqlite3_int64 estimatedRows; /* Estimated number of rows returned */ 7858 /* Fields below are only available in SQLite 3.9.0 and later */ 7859 int idxFlags; /* Mask of SQLITE_INDEX_SCAN_* flags */ 7860 /* Fields below are only available in SQLite 3.10.0 and later */ 7861 sqlite3_uint64 colUsed; /* Input: Mask of columns used by statement */ 7862 }; 7863 7864 /* 7865 ** CAPI3REF: Virtual Table Scan Flags 7866 ** 7867 ** Virtual table implementations are allowed to set the 7868 ** [sqlite3_index_info].idxFlags field to some combination of 7869 ** these bits. 7870 */ 7871 #define SQLITE_INDEX_SCAN_UNIQUE 0x00000001 /* Scan visits at most 1 row */ 7872 #define SQLITE_INDEX_SCAN_HEX 0x00000002 /* Display idxNum as hex */ 7873 /* in EXPLAIN QUERY PLAN */ 7874 7875 /* 7876 ** CAPI3REF: Virtual Table Constraint Operator Codes 7877 ** 7878 ** These macros define the allowed values for the 7879 ** [sqlite3_index_info].aConstraint[].op field. Each value represents 7880 ** an operator that is part of a constraint term in the WHERE clause of 7881 ** a query that uses a [virtual table]. 7882 ** 7883 ** ^The left-hand operand of the operator is given by the corresponding 7884 ** aConstraint[].iColumn field. ^An iColumn of -1 indicates the left-hand 7885 ** operand is the rowid. 7886 ** The SQLITE_INDEX_CONSTRAINT_LIMIT and SQLITE_INDEX_CONSTRAINT_OFFSET 7887 ** operators have no left-hand operand, and so for those operators the 7888 ** corresponding aConstraint[].iColumn is meaningless and should not be 7889 ** used. 7890 ** 7891 ** All operator values from SQLITE_INDEX_CONSTRAINT_FUNCTION through 7892 ** value 255 are reserved to represent functions that are overloaded 7893 ** by the [xFindFunction|xFindFunction method] of the virtual table 7894 ** implementation. 7895 ** 7896 ** The right-hand operands for each constraint might be accessible using 7897 ** the [sqlite3_vtab_rhs_value()] interface. Usually the right-hand 7898 ** operand is only available if it appears as a single constant literal 7899 ** in the input SQL. If the right-hand operand is another column or an 7900 ** expression (even a constant expression) or a parameter, then the 7901 ** sqlite3_vtab_rhs_value() probably will not be able to extract it. 7902 ** ^The SQLITE_INDEX_CONSTRAINT_ISNULL and 7903 ** SQLITE_INDEX_CONSTRAINT_ISNOTNULL operators have no right-hand operand 7904 ** and hence calls to sqlite3_vtab_rhs_value() for those operators will 7905 ** always return SQLITE_NOTFOUND. 7906 ** 7907 ** The collating sequence to be used for comparison can be found using 7908 ** the [sqlite3_vtab_collation()] interface. For most real-world virtual 7909 ** tables, the collating sequence of constraints does not matter (for example 7910 ** because the constraints are numeric) and so the sqlite3_vtab_collation() 7911 ** interface is not commonly needed. 7912 */ 7913 #define SQLITE_INDEX_CONSTRAINT_EQ 2 7914 #define SQLITE_INDEX_CONSTRAINT_GT 4 7915 #define SQLITE_INDEX_CONSTRAINT_LE 8 7916 #define SQLITE_INDEX_CONSTRAINT_LT 16 7917 #define SQLITE_INDEX_CONSTRAINT_GE 32 7918 #define SQLITE_INDEX_CONSTRAINT_MATCH 64 7919 #define SQLITE_INDEX_CONSTRAINT_LIKE 65 7920 #define SQLITE_INDEX_CONSTRAINT_GLOB 66 7921 #define SQLITE_INDEX_CONSTRAINT_REGEXP 67 7922 #define SQLITE_INDEX_CONSTRAINT_NE 68 7923 #define SQLITE_INDEX_CONSTRAINT_ISNOT 69 7924 #define SQLITE_INDEX_CONSTRAINT_ISNOTNULL 70 7925 #define SQLITE_INDEX_CONSTRAINT_ISNULL 71 7926 #define SQLITE_INDEX_CONSTRAINT_IS 72 7927 #define SQLITE_INDEX_CONSTRAINT_LIMIT 73 7928 #define SQLITE_INDEX_CONSTRAINT_OFFSET 74 7929 #define SQLITE_INDEX_CONSTRAINT_FUNCTION 150 7930 7931 /* 7932 ** CAPI3REF: Register A Virtual Table Implementation 7933 ** METHOD: sqlite3 7934 ** 7935 ** ^These routines are used to register a new [virtual table module] name. 7936 ** ^Module names must be registered before 7937 ** creating a new [virtual table] using the module and before using a 7938 ** preexisting [virtual table] for the module. 7939 ** 7940 ** ^The module name is registered on the [database connection] specified 7941 ** by the first parameter. ^The name of the module is given by the 7942 ** second parameter. ^The third parameter is a pointer to 7943 ** the implementation of the [virtual table module]. ^The fourth 7944 ** parameter is an arbitrary client data pointer that is passed through 7945 ** into the [xCreate] and [xConnect] methods of the virtual table module 7946 ** when a new virtual table is being created or reinitialized. 7947 ** 7948 ** ^The sqlite3_create_module_v2() interface has a fifth parameter which 7949 ** is a pointer to a destructor for the pClientData. ^SQLite will 7950 ** invoke the destructor function (if it is not NULL) when SQLite 7951 ** no longer needs the pClientData pointer. ^The destructor will also 7952 ** be invoked if the call to sqlite3_create_module_v2() fails. 7953 ** ^The sqlite3_create_module() 7954 ** interface is equivalent to sqlite3_create_module_v2() with a NULL 7955 ** destructor. 7956 ** 7957 ** ^If the third parameter (the pointer to the sqlite3_module object) is 7958 ** NULL then no new module is created and any existing modules with the 7959 ** same name are dropped. 7960 ** 7961 ** See also: [sqlite3_drop_modules()] 7962 */ 7963 SQLITE_API int sqlite3_create_module( 7964 sqlite3 *db, /* SQLite connection to register module with */ 7965 const char *zName, /* Name of the module */ 7966 const sqlite3_module *p, /* Methods for the module */ 7967 void *pClientData /* Client data for xCreate/xConnect */ 7968 ); 7969 SQLITE_API int sqlite3_create_module_v2( 7970 sqlite3 *db, /* SQLite connection to register module with */ 7971 const char *zName, /* Name of the module */ 7972 const sqlite3_module *p, /* Methods for the module */ 7973 void *pClientData, /* Client data for xCreate/xConnect */ 7974 void(*xDestroy)(void*) /* Module destructor function */ 7975 ); 7976 7977 /* 7978 ** CAPI3REF: Remove Unnecessary Virtual Table Implementations 7979 ** METHOD: sqlite3 7980 ** 7981 ** ^The sqlite3_drop_modules(D,L) interface removes all virtual 7982 ** table modules from database connection D except those named on list L. 7983 ** The L parameter must be either NULL or a pointer to an array of pointers 7984 ** to strings where the array is terminated by a single NULL pointer. 7985 ** ^If the L parameter is NULL, then all virtual table modules are removed. 7986 ** 7987 ** See also: [sqlite3_create_module()] 7988 */ 7989 SQLITE_API int sqlite3_drop_modules( 7990 sqlite3 *db, /* Remove modules from this connection */ 7991 const char **azKeep /* Except, do not remove the ones named here */ 7992 ); 7993 7994 /* 7995 ** CAPI3REF: Virtual Table Instance Object 7996 ** KEYWORDS: sqlite3_vtab 7997 ** 7998 ** Every [virtual table module] implementation uses a subclass 7999 ** of this object to describe a particular instance 8000 ** of the [virtual table]. Each subclass will 8001 ** be tailored to the specific needs of the module implementation. 8002 ** The purpose of this superclass is to define certain fields that are 8003 ** common to all module implementations. 8004 ** 8005 ** ^Virtual tables methods can set an error message by assigning a 8006 ** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should 8007 ** take care that any prior string is freed by a call to [sqlite3_free()] 8008 ** prior to assigning a new string to zErrMsg. ^After the error message 8009 ** is delivered up to the client application, the string will be automatically 8010 ** freed by sqlite3_free() and the zErrMsg field will be zeroed. 8011 */ 8012 struct sqlite3_vtab { 8013 const sqlite3_module *pModule; /* The module for this virtual table */ 8014 int nRef; /* Number of open cursors */ 8015 char *zErrMsg; /* Error message from sqlite3_mprintf() */ 8016 /* Virtual table implementations will typically add additional fields */ 8017 }; 8018 8019 /* 8020 ** CAPI3REF: Virtual Table Cursor Object 8021 ** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor} 8022 ** 8023 ** Every [virtual table module] implementation uses a subclass of the 8024 ** following structure to describe cursors that point into the 8025 ** [virtual table] and are used 8026 ** to loop through the virtual table. Cursors are created using the 8027 ** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed 8028 ** by the [sqlite3_module.xClose | xClose] method. Cursors are used 8029 ** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods 8030 ** of the module. Each module implementation will define 8031 ** the content of a cursor structure to suit its own needs. 8032 ** 8033 ** This superclass exists in order to define fields of the cursor that 8034 ** are common to all implementations. 8035 */ 8036 struct sqlite3_vtab_cursor { 8037 sqlite3_vtab *pVtab; /* Virtual table of this cursor */ 8038 /* Virtual table implementations will typically add additional fields */ 8039 }; 8040 8041 /* 8042 ** CAPI3REF: Declare The Schema Of A Virtual Table 8043 ** 8044 ** ^The [xCreate] and [xConnect] methods of a 8045 ** [virtual table module] call this interface 8046 ** to declare the format (the names and datatypes of the columns) of 8047 ** the virtual tables they implement. 8048 */ 8049 SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zSQL); 8050 8051 /* 8052 ** CAPI3REF: Overload A Function For A Virtual Table 8053 ** METHOD: sqlite3 8054 ** 8055 ** ^(Virtual tables can provide alternative implementations of functions 8056 ** using the [xFindFunction] method of the [virtual table module]. 8057 ** But global versions of those functions 8058 ** must exist in order to be overloaded.)^ 8059 ** 8060 ** ^(This API makes sure a global version of a function with a particular 8061 ** name and number of parameters exists. If no such function exists 8062 ** before this API is called, a new function is created.)^ ^The implementation 8063 ** of the new function always causes an exception to be thrown. So 8064 ** the new function is not good for anything by itself. Its only 8065 ** purpose is to be a placeholder function that can be overloaded 8066 ** by a [virtual table]. 8067 */ 8068 SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg); 8069 8070 /* 8071 ** CAPI3REF: A Handle To An Open BLOB 8072 ** KEYWORDS: {BLOB handle} {BLOB handles} 8073 ** 8074 ** An instance of this object represents an open BLOB on which 8075 ** [sqlite3_blob_open | incremental BLOB I/O] can be performed. 8076 ** ^Objects of this type are created by [sqlite3_blob_open()] 8077 ** and destroyed by [sqlite3_blob_close()]. 8078 ** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces 8079 ** can be used to read or write small subsections of the BLOB. 8080 ** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes. 8081 */ 8082 typedef struct sqlite3_blob sqlite3_blob; 8083 8084 /* 8085 ** CAPI3REF: Open A BLOB For Incremental I/O 8086 ** METHOD: sqlite3 8087 ** CONSTRUCTOR: sqlite3_blob 8088 ** 8089 ** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located 8090 ** in row iRow, column zColumn, table zTable in database zDb; 8091 ** in other words, the same BLOB that would be selected by: 8092 ** 8093 ** <pre> 8094 ** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow; 8095 ** </pre>)^ 8096 ** 8097 ** ^(Parameter zDb is not the filename that contains the database, but 8098 ** rather the symbolic name of the database. For attached databases, this is 8099 ** the name that appears after the AS keyword in the [ATTACH] statement. 8100 ** For the main database file, the database name is "main". For TEMP 8101 ** tables, the database name is "temp".)^ 8102 ** 8103 ** ^If the flags parameter is non-zero, then the BLOB is opened for read 8104 ** and write access. ^If the flags parameter is zero, the BLOB is opened for 8105 ** read-only access. 8106 ** 8107 ** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is stored 8108 ** in *ppBlob. Otherwise an [error code] is returned and, unless the error 8109 ** code is SQLITE_MISUSE, *ppBlob is set to NULL.)^ ^This means that, provided 8110 ** the API is not misused, it is always safe to call [sqlite3_blob_close()] 8111 ** on *ppBlob after this function returns. 8112 ** 8113 ** This function fails with SQLITE_ERROR if any of the following are true: 8114 ** <ul> 8115 ** <li> ^(Database zDb does not exist)^, 8116 ** <li> ^(Table zTable does not exist within database zDb)^, 8117 ** <li> ^(Table zTable is a WITHOUT ROWID table)^, 8118 ** <li> ^(Column zColumn does not exist)^, 8119 ** <li> ^(Row iRow is not present in the table)^, 8120 ** <li> ^(The specified column of row iRow contains a value that is not 8121 ** a TEXT or BLOB value)^, 8122 ** <li> ^(Column zColumn is part of an index, PRIMARY KEY or UNIQUE 8123 ** constraint and the blob is being opened for read/write access)^, 8124 ** <li> ^([foreign key constraints | Foreign key constraints] are enabled, 8125 ** column zColumn is part of a [child key] definition and the blob is 8126 ** being opened for read/write access)^. 8127 ** </ul> 8128 ** 8129 ** ^Unless it returns SQLITE_MISUSE, this function sets the 8130 ** [database connection] error code and message accessible via 8131 ** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. 8132 ** 8133 ** A BLOB referenced by sqlite3_blob_open() may be read using the 8134 ** [sqlite3_blob_read()] interface and modified by using 8135 ** [sqlite3_blob_write()]. The [BLOB handle] can be moved to a 8136 ** different row of the same table using the [sqlite3_blob_reopen()] 8137 ** interface. However, the column, table, or database of a [BLOB handle] 8138 ** cannot be changed after the [BLOB handle] is opened. 8139 ** 8140 ** ^(If the row that a BLOB handle points to is modified by an 8141 ** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects 8142 ** then the BLOB handle is marked as "expired". 8143 ** This is true if any column of the row is changed, even a column 8144 ** other than the one the BLOB handle is open on.)^ 8145 ** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for 8146 ** an expired BLOB handle fail with a return code of [SQLITE_ABORT]. 8147 ** ^(Changes written into a BLOB prior to the BLOB expiring are not 8148 ** rolled back by the expiration of the BLOB. Such changes will eventually 8149 ** commit if the transaction continues to completion.)^ 8150 ** 8151 ** ^Use the [sqlite3_blob_bytes()] interface to determine the size of 8152 ** the opened blob. ^The size of a blob may not be changed by this 8153 ** interface. Use the [UPDATE] SQL command to change the size of a 8154 ** blob. 8155 ** 8156 ** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces 8157 ** and the built-in [zeroblob] SQL function may be used to create a 8158 ** zero-filled blob to read or write using the incremental-blob interface. 8159 ** 8160 ** To avoid a resource leak, every open [BLOB handle] should eventually 8161 ** be released by a call to [sqlite3_blob_close()]. 8162 ** 8163 ** See also: [sqlite3_blob_close()], 8164 ** [sqlite3_blob_reopen()], [sqlite3_blob_read()], 8165 ** [sqlite3_blob_bytes()], [sqlite3_blob_write()]. 8166 */ 8167 SQLITE_API int sqlite3_blob_open( 8168 sqlite3*, 8169 const char *zDb, 8170 const char *zTable, 8171 const char *zColumn, 8172 sqlite3_int64 iRow, 8173 int flags, 8174 sqlite3_blob **ppBlob 8175 ); 8176 8177 /* 8178 ** CAPI3REF: Move a BLOB Handle to a New Row 8179 ** METHOD: sqlite3_blob 8180 ** 8181 ** ^This function is used to move an existing [BLOB handle] so that it points 8182 ** to a different row of the same database table. ^The new row is identified 8183 ** by the rowid value passed as the second argument. Only the row can be 8184 ** changed. ^The database, table and column on which the blob handle is open 8185 ** remain the same. Moving an existing [BLOB handle] to a new row is 8186 ** faster than closing the existing handle and opening a new one. 8187 ** 8188 ** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] - 8189 ** it must exist and there must be either a blob or text value stored in 8190 ** the nominated column.)^ ^If the new row is not present in the table, or if 8191 ** it does not contain a blob or text value, or if another error occurs, an 8192 ** SQLite error code is returned and the blob handle is considered aborted. 8193 ** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or 8194 ** [sqlite3_blob_reopen()] on an aborted blob handle immediately return 8195 ** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle 8196 ** always returns zero. 8197 ** 8198 ** ^This function sets the database handle error code and message. 8199 */ 8200 SQLITE_API int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64); 8201 8202 /* 8203 ** CAPI3REF: Close A BLOB Handle 8204 ** DESTRUCTOR: sqlite3_blob 8205 ** 8206 ** ^This function closes an open [BLOB handle]. ^(The BLOB handle is closed 8207 ** unconditionally. Even if this routine returns an error code, the 8208 ** handle is still closed.)^ 8209 ** 8210 ** ^If the blob handle being closed was opened for read-write access, and if 8211 ** the database is in auto-commit mode and there are no other open read-write 8212 ** blob handles or active write statements, the current transaction is 8213 ** committed. ^If an error occurs while committing the transaction, an error 8214 ** code is returned and the transaction rolled back. 8215 ** 8216 ** Calling this function with an argument that is not a NULL pointer or an 8217 ** open blob handle results in undefined behavior. ^Calling this routine 8218 ** with a null pointer (such as would be returned by a failed call to 8219 ** [sqlite3_blob_open()]) is a harmless no-op. ^Otherwise, if this function 8220 ** is passed a valid open blob handle, the values returned by the 8221 ** sqlite3_errcode() and sqlite3_errmsg() functions are set before returning. 8222 */ 8223 SQLITE_API int sqlite3_blob_close(sqlite3_blob *); 8224 8225 /* 8226 ** CAPI3REF: Return The Size Of An Open BLOB 8227 ** METHOD: sqlite3_blob 8228 ** 8229 ** ^Returns the size in bytes of the BLOB accessible via the 8230 ** successfully opened [BLOB handle] in its only argument. ^The 8231 ** incremental blob I/O routines can only read or overwrite existing 8232 ** blob content; they cannot change the size of a blob. 8233 ** 8234 ** This routine only works on a [BLOB handle] which has been created 8235 ** by a prior successful call to [sqlite3_blob_open()] and which has not 8236 ** been closed by [sqlite3_blob_close()]. Passing any other pointer in 8237 ** to this routine results in undefined and probably undesirable behavior. 8238 */ 8239 SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *); 8240 8241 /* 8242 ** CAPI3REF: Read Data From A BLOB Incrementally 8243 ** METHOD: sqlite3_blob 8244 ** 8245 ** ^(This function is used to read data from an open [BLOB handle] into a 8246 ** caller-supplied buffer. N bytes of data are copied into buffer Z 8247 ** from the open BLOB, starting at offset iOffset.)^ 8248 ** 8249 ** ^If offset iOffset is less than N bytes from the end of the BLOB, 8250 ** [SQLITE_ERROR] is returned and no data is read. ^If N or iOffset is 8251 ** less than zero, [SQLITE_ERROR] is returned and no data is read. 8252 ** ^The size of the blob (and hence the maximum value of N+iOffset) 8253 ** can be determined using the [sqlite3_blob_bytes()] interface. 8254 ** 8255 ** ^An attempt to read from an expired [BLOB handle] fails with an 8256 ** error code of [SQLITE_ABORT]. 8257 ** 8258 ** ^(On success, sqlite3_blob_read() returns SQLITE_OK. 8259 ** Otherwise, an [error code] or an [extended error code] is returned.)^ 8260 ** 8261 ** This routine only works on a [BLOB handle] which has been created 8262 ** by a prior successful call to [sqlite3_blob_open()] and which has not 8263 ** been closed by [sqlite3_blob_close()]. Passing any other pointer in 8264 ** to this routine results in undefined and probably undesirable behavior. 8265 ** 8266 ** See also: [sqlite3_blob_write()]. 8267 */ 8268 SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset); 8269 8270 /* 8271 ** CAPI3REF: Write Data Into A BLOB Incrementally 8272 ** METHOD: sqlite3_blob 8273 ** 8274 ** ^(This function is used to write data into an open [BLOB handle] from a 8275 ** caller-supplied buffer. N bytes of data are copied from the buffer Z 8276 ** into the open BLOB, starting at offset iOffset.)^ 8277 ** 8278 ** ^(On success, sqlite3_blob_write() returns SQLITE_OK. 8279 ** Otherwise, an [error code] or an [extended error code] is returned.)^ 8280 ** ^Unless SQLITE_MISUSE is returned, this function sets the 8281 ** [database connection] error code and message accessible via 8282 ** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. 8283 ** 8284 ** ^If the [BLOB handle] passed as the first argument was not opened for 8285 ** writing (the flags parameter to [sqlite3_blob_open()] was zero), 8286 ** this function returns [SQLITE_READONLY]. 8287 ** 8288 ** This function may only modify the contents of the BLOB; it is 8289 ** not possible to increase the size of a BLOB using this API. 8290 ** ^If offset iOffset is less than N bytes from the end of the BLOB, 8291 ** [SQLITE_ERROR] is returned and no data is written. The size of the 8292 ** BLOB (and hence the maximum value of N+iOffset) can be determined 8293 ** using the [sqlite3_blob_bytes()] interface. ^If N or iOffset are less 8294 ** than zero [SQLITE_ERROR] is returned and no data is written. 8295 ** 8296 ** ^An attempt to write to an expired [BLOB handle] fails with an 8297 ** error code of [SQLITE_ABORT]. ^Writes to the BLOB that occurred 8298 ** before the [BLOB handle] expired are not rolled back by the 8299 ** expiration of the handle, though of course those changes might 8300 ** have been overwritten by the statement that expired the BLOB handle 8301 ** or by other independent statements. 8302 ** 8303 ** This routine only works on a [BLOB handle] which has been created 8304 ** by a prior successful call to [sqlite3_blob_open()] and which has not 8305 ** been closed by [sqlite3_blob_close()]. Passing any other pointer in 8306 ** to this routine results in undefined and probably undesirable behavior. 8307 ** 8308 ** See also: [sqlite3_blob_read()]. 8309 */ 8310 SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset); 8311 8312 /* 8313 ** CAPI3REF: Virtual File System Objects 8314 ** 8315 ** A virtual filesystem (VFS) is an [sqlite3_vfs] object 8316 ** that SQLite uses to interact 8317 ** with the underlying operating system. Most SQLite builds come with a 8318 ** single default VFS that is appropriate for the host computer. 8319 ** New VFSes can be registered and existing VFSes can be unregistered. 8320 ** The following interfaces are provided. 8321 ** 8322 ** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name. 8323 ** ^Names are case sensitive. 8324 ** ^Names are zero-terminated UTF-8 strings. 8325 ** ^If there is no match, a NULL pointer is returned. 8326 ** ^If zVfsName is NULL then the default VFS is returned. 8327 ** 8328 ** ^New VFSes are registered with sqlite3_vfs_register(). 8329 ** ^Each new VFS becomes the default VFS if the makeDflt flag is set. 8330 ** ^The same VFS can be registered multiple times without injury. 8331 ** ^To make an existing VFS into the default VFS, register it again 8332 ** with the makeDflt flag set. If two different VFSes with the 8333 ** same name are registered, the behavior is undefined. If a 8334 ** VFS is registered with a name that is NULL or an empty string, 8335 ** then the behavior is undefined. 8336 ** 8337 ** ^Unregister a VFS with the sqlite3_vfs_unregister() interface. 8338 ** ^(If the default VFS is unregistered, another VFS is chosen as 8339 ** the default. The choice for the new VFS is arbitrary.)^ 8340 */ 8341 SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName); 8342 SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt); 8343 SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*); 8344 8345 /* 8346 ** CAPI3REF: Mutexes 8347 ** 8348 ** The SQLite core uses these routines for thread 8349 ** synchronization. Though they are intended for internal 8350 ** use by SQLite, code that links against SQLite is 8351 ** permitted to use any of these routines. 8352 ** 8353 ** The SQLite source code contains multiple implementations 8354 ** of these mutex routines. An appropriate implementation 8355 ** is selected automatically at compile-time. The following 8356 ** implementations are available in the SQLite core: 8357 ** 8358 ** <ul> 8359 ** <li> SQLITE_MUTEX_PTHREADS 8360 ** <li> SQLITE_MUTEX_W32 8361 ** <li> SQLITE_MUTEX_NOOP 8362 ** </ul> 8363 ** 8364 ** The SQLITE_MUTEX_NOOP implementation is a set of routines 8365 ** that does no real locking and is appropriate for use in 8366 ** a single-threaded application. The SQLITE_MUTEX_PTHREADS and 8367 ** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix 8368 ** and Windows. 8369 ** 8370 ** 8371 ** ^The sqlite3_mutex_alloc() routine allocates a new 8372 ** mutex and returns a pointer to it. ^The sqlite3_mutex_alloc() 8373 ** routine returns NULL if it is unable to allocate the requested 8374 ** mutex. The argument to sqlite3_mutex_alloc() must be one of these 8375 ** integer constants: 8376 ** 8377 ** <ul> 8378 ** <li> SQLITE_MUTEX_FAST 8379 ** <li> SQLITE_MUTEX_RECURSIVE 8380 ** <li> SQLITE_MUTEX_STATIC_MAIN 8381 ** <li> SQLITE_MUTEX_STATIC_MEM 8382 ** <li> SQLITE_MUTEX_STATIC_OPEN 8383 ** <li> SQLITE_MUTEX_STATIC_PRNG 8384 ** <li> SQLITE_MUTEX_STATIC_LRU 8385 ** <li> SQLITE_MUTEX_STATIC_PMEM 8386 ** <li> SQLITE_MUTEX_STATIC_APP1 8387 ** <li> SQLITE_MUTEX_STATIC_APP2 8388 ** <li> SQLITE_MUTEX_STATIC_APP3 8389 ** <li> SQLITE_MUTEX_STATIC_VFS1 8390 ** <li> SQLITE_MUTEX_STATIC_VFS2 8391 ** <li> SQLITE_MUTEX_STATIC_VFS3 8392 ** </ul> 8393 ** 8394 ** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) 8395 ** cause sqlite3_mutex_alloc() to create 8396 ** a new mutex. ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE 8397 ** is used but not necessarily so when SQLITE_MUTEX_FAST is used. 8398 ** The mutex implementation does not need to make a distinction 8399 ** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does 8400 ** not want to. SQLite will only request a recursive mutex in 8401 ** cases where it really needs one. If a faster non-recursive mutex 8402 ** implementation is available on the host platform, the mutex subsystem 8403 ** might return such a mutex in response to SQLITE_MUTEX_FAST. 8404 ** 8405 ** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other 8406 ** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return 8407 ** a pointer to a static preexisting mutex. ^Nine static mutexes are 8408 ** used by the current version of SQLite. Future versions of SQLite 8409 ** may add additional static mutexes. Static mutexes are for internal 8410 ** use by SQLite only. Applications that use SQLite mutexes should 8411 ** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or 8412 ** SQLITE_MUTEX_RECURSIVE. 8413 ** 8414 ** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST 8415 ** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc() 8416 ** returns a different mutex on every call. ^For the static 8417 ** mutex types, the same mutex is returned on every call that has 8418 ** the same type number. 8419 ** 8420 ** ^The sqlite3_mutex_free() routine deallocates a previously 8421 ** allocated dynamic mutex. Attempting to deallocate a static 8422 ** mutex results in undefined behavior. 8423 ** 8424 ** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt 8425 ** to enter a mutex. ^If another thread is already within the mutex, 8426 ** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return 8427 ** SQLITE_BUSY. ^The sqlite3_mutex_try() interface returns [SQLITE_OK] 8428 ** upon successful entry. ^(Mutexes created using 8429 ** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread. 8430 ** In such cases, the 8431 ** mutex must be exited an equal number of times before another thread 8432 ** can enter.)^ If the same thread tries to enter any mutex other 8433 ** than an SQLITE_MUTEX_RECURSIVE more than once, the behavior is undefined. 8434 ** 8435 ** ^(Some systems (for example, Windows 95) do not support the operation 8436 ** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try() 8437 ** will always return SQLITE_BUSY. In most cases the SQLite core only uses 8438 ** sqlite3_mutex_try() as an optimization, so this is acceptable 8439 ** behavior. The exceptions are unix builds that set the 8440 ** SQLITE_ENABLE_SETLK_TIMEOUT build option. In that case a working 8441 ** sqlite3_mutex_try() is required.)^ 8442 ** 8443 ** ^The sqlite3_mutex_leave() routine exits a mutex that was 8444 ** previously entered by the same thread. The behavior 8445 ** is undefined if the mutex is not currently entered by the 8446 ** calling thread or is not currently allocated. 8447 ** 8448 ** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), 8449 ** sqlite3_mutex_leave(), or sqlite3_mutex_free() is a NULL pointer, 8450 ** then any of the four routines behaves as a no-op. 8451 ** 8452 ** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()]. 8453 */ 8454 SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int); 8455 SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*); 8456 SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*); 8457 SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*); 8458 SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*); 8459 8460 /* 8461 ** CAPI3REF: Mutex Methods Object 8462 ** 8463 ** An instance of this structure defines the low-level routines 8464 ** used to allocate and use mutexes. 8465 ** 8466 ** Usually, the default mutex implementations provided by SQLite are 8467 ** sufficient, however the application has the option of substituting a custom 8468 ** implementation for specialized deployments or systems for which SQLite 8469 ** does not provide a suitable implementation. In this case, the application 8470 ** creates and populates an instance of this structure to pass 8471 ** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option. 8472 ** Additionally, an instance of this structure can be used as an 8473 ** output variable when querying the system for the current mutex 8474 ** implementation, using the [SQLITE_CONFIG_GETMUTEX] option. 8475 ** 8476 ** ^The xMutexInit method defined by this structure is invoked as 8477 ** part of system initialization by the sqlite3_initialize() function. 8478 ** ^The xMutexInit routine is called by SQLite exactly once for each 8479 ** effective call to [sqlite3_initialize()]. 8480 ** 8481 ** ^The xMutexEnd method defined by this structure is invoked as 8482 ** part of system shutdown by the sqlite3_shutdown() function. The 8483 ** implementation of this method is expected to release all outstanding 8484 ** resources obtained by the mutex methods implementation, especially 8485 ** those obtained by the xMutexInit method. ^The xMutexEnd() 8486 ** interface is invoked exactly once for each call to [sqlite3_shutdown()]. 8487 ** 8488 ** ^(The remaining seven methods defined by this structure (xMutexAlloc, 8489 ** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and 8490 ** xMutexNotheld) implement the following interfaces (respectively): 8491 ** 8492 ** <ul> 8493 ** <li> [sqlite3_mutex_alloc()] </li> 8494 ** <li> [sqlite3_mutex_free()] </li> 8495 ** <li> [sqlite3_mutex_enter()] </li> 8496 ** <li> [sqlite3_mutex_try()] </li> 8497 ** <li> [sqlite3_mutex_leave()] </li> 8498 ** <li> [sqlite3_mutex_held()] </li> 8499 ** <li> [sqlite3_mutex_notheld()] </li> 8500 ** </ul>)^ 8501 ** 8502 ** The only difference is that the public sqlite3_XXX functions enumerated 8503 ** above silently ignore any invocations that pass a NULL pointer instead 8504 ** of a valid mutex handle. The implementations of the methods defined 8505 ** by this structure are not required to handle this case. The results 8506 ** of passing a NULL pointer instead of a valid mutex handle are undefined 8507 ** (i.e. it is acceptable to provide an implementation that segfaults if 8508 ** it is passed a NULL pointer). 8509 ** 8510 ** The xMutexInit() method must be threadsafe. It must be harmless to 8511 ** invoke xMutexInit() multiple times within the same process and without 8512 ** intervening calls to xMutexEnd(). Second and subsequent calls to 8513 ** xMutexInit() must be no-ops. 8514 ** 8515 ** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()] 8516 ** and its associates). Similarly, xMutexAlloc() must not use SQLite memory 8517 ** allocation for a static mutex. ^However xMutexAlloc() may use SQLite 8518 ** memory allocation for a fast or recursive mutex. 8519 ** 8520 ** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is 8521 ** called, but only if the prior call to xMutexInit returned SQLITE_OK. 8522 ** If xMutexInit fails in any way, it is expected to clean up after itself 8523 ** prior to returning. 8524 */ 8525 typedef struct sqlite3_mutex_methods sqlite3_mutex_methods; 8526 struct sqlite3_mutex_methods { 8527 int (*xMutexInit)(void); 8528 int (*xMutexEnd)(void); 8529 sqlite3_mutex *(*xMutexAlloc)(int); 8530 void (*xMutexFree)(sqlite3_mutex *); 8531 void (*xMutexEnter)(sqlite3_mutex *); 8532 int (*xMutexTry)(sqlite3_mutex *); 8533 void (*xMutexLeave)(sqlite3_mutex *); 8534 int (*xMutexHeld)(sqlite3_mutex *); 8535 int (*xMutexNotheld)(sqlite3_mutex *); 8536 }; 8537 8538 /* 8539 ** CAPI3REF: Mutex Verification Routines 8540 ** 8541 ** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines 8542 ** are intended for use inside assert() statements. The SQLite core 8543 ** never uses these routines except inside an assert() and applications 8544 ** are advised to follow the lead of the core. The SQLite core only 8545 ** provides implementations for these routines when it is compiled 8546 ** with the SQLITE_DEBUG flag. External mutex implementations 8547 ** are only required to provide these routines if SQLITE_DEBUG is 8548 ** defined and if NDEBUG is not defined. 8549 ** 8550 ** These routines should return true if the mutex in their argument 8551 ** is held or not held, respectively, by the calling thread. 8552 ** 8553 ** The implementation is not required to provide versions of these 8554 ** routines that actually work. If the implementation does not provide working 8555 ** versions of these routines, it should at least provide stubs that always 8556 ** return true so that one does not get spurious assertion failures. 8557 ** 8558 ** If the argument to sqlite3_mutex_held() is a NULL pointer then 8559 ** the routine should return 1. This seems counter-intuitive since 8560 ** clearly the mutex cannot be held if it does not exist. But 8561 ** the reason the mutex does not exist is because the build is not 8562 ** using mutexes. And we do not want the assert() containing the 8563 ** call to sqlite3_mutex_held() to fail, so a non-zero return is 8564 ** the appropriate thing to do. The sqlite3_mutex_notheld() 8565 ** interface should also return 1 when given a NULL pointer. 8566 */ 8567 #ifndef NDEBUG 8568 SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*); 8569 SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*); 8570 #endif 8571 8572 /* 8573 ** CAPI3REF: Mutex Types 8574 ** 8575 ** The [sqlite3_mutex_alloc()] interface takes a single argument 8576 ** which is one of these integer constants. 8577 ** 8578 ** The set of static mutexes may change from one SQLite release to the 8579 ** next. Applications that override the built-in mutex logic must be 8580 ** prepared to accommodate additional static mutexes. 8581 */ 8582 #define SQLITE_MUTEX_FAST 0 8583 #define SQLITE_MUTEX_RECURSIVE 1 8584 #define SQLITE_MUTEX_STATIC_MAIN 2 8585 #define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */ 8586 #define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */ 8587 #define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */ 8588 #define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_randomness() */ 8589 #define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */ 8590 #define SQLITE_MUTEX_STATIC_LRU2 7 /* NOT USED */ 8591 #define SQLITE_MUTEX_STATIC_PMEM 7 /* sqlite3PageMalloc() */ 8592 #define SQLITE_MUTEX_STATIC_APP1 8 /* For use by application */ 8593 #define SQLITE_MUTEX_STATIC_APP2 9 /* For use by application */ 8594 #define SQLITE_MUTEX_STATIC_APP3 10 /* For use by application */ 8595 #define SQLITE_MUTEX_STATIC_VFS1 11 /* For use by built-in VFS */ 8596 #define SQLITE_MUTEX_STATIC_VFS2 12 /* For use by extension VFS */ 8597 #define SQLITE_MUTEX_STATIC_VFS3 13 /* For use by application VFS */ 8598 8599 /* Legacy compatibility: */ 8600 #define SQLITE_MUTEX_STATIC_MASTER 2 8601 8602 8603 /* 8604 ** CAPI3REF: Retrieve the mutex for a database connection 8605 ** METHOD: sqlite3 8606 ** 8607 ** ^This interface returns a pointer to the [sqlite3_mutex] object that 8608 ** serializes access to the [database connection] given in the argument 8609 ** when the [threading mode] is Serialized. 8610 ** ^If the [threading mode] is Single-thread or Multi-thread then this 8611 ** routine returns a NULL pointer. 8612 */ 8613 SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*); 8614 8615 /* 8616 ** CAPI3REF: Low-Level Control Of Database Files 8617 ** METHOD: sqlite3 8618 ** KEYWORDS: {file control} 8619 ** 8620 ** ^The [sqlite3_file_control()] interface makes a direct call to the 8621 ** xFileControl method for the [sqlite3_io_methods] object associated 8622 ** with a particular database identified by the second argument. ^The 8623 ** name of the database is "main" for the main database or "temp" for the 8624 ** TEMP database, or the name that appears after the AS keyword for 8625 ** databases that are added using the [ATTACH] SQL command. 8626 ** ^A NULL pointer can be used in place of "main" to refer to the 8627 ** main database file. 8628 ** ^The third and fourth parameters to this routine 8629 ** are passed directly through to the second and third parameters of 8630 ** the xFileControl method. ^The return value of the xFileControl 8631 ** method becomes the return value of this routine. 8632 ** 8633 ** A few opcodes for [sqlite3_file_control()] are handled directly 8634 ** by the SQLite core and never invoke the 8635 ** sqlite3_io_methods.xFileControl method. 8636 ** ^The [SQLITE_FCNTL_FILE_POINTER] value for the op parameter causes 8637 ** a pointer to the underlying [sqlite3_file] object to be written into 8638 ** the space pointed to by the 4th parameter. The 8639 ** [SQLITE_FCNTL_JOURNAL_POINTER] works similarly except that it returns 8640 ** the [sqlite3_file] object associated with the journal file instead of 8641 ** the main database. The [SQLITE_FCNTL_VFS_POINTER] opcode returns 8642 ** a pointer to the underlying [sqlite3_vfs] object for the file. 8643 ** The [SQLITE_FCNTL_DATA_VERSION] returns the data version counter 8644 ** from the pager. 8645 ** 8646 ** ^If the second parameter (zDbName) does not match the name of any 8647 ** open database file, then SQLITE_ERROR is returned. ^This error 8648 ** code is not remembered and will not be recalled by [sqlite3_errcode()] 8649 ** or [sqlite3_errmsg()]. The underlying xFileControl method might 8650 ** also return SQLITE_ERROR. There is no way to distinguish between 8651 ** an incorrect zDbName and an SQLITE_ERROR return from the underlying 8652 ** xFileControl method. 8653 ** 8654 ** See also: [file control opcodes] 8655 */ 8656 SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*); 8657 8658 /* 8659 ** CAPI3REF: Testing Interface 8660 ** 8661 ** ^The sqlite3_test_control() interface is used to read out internal 8662 ** state of SQLite and to inject faults into SQLite for testing 8663 ** purposes. ^The first parameter is an operation code that determines 8664 ** the number, meaning, and operation of all subsequent parameters. 8665 ** 8666 ** This interface is not for use by applications. It exists solely 8667 ** for verifying the correct operation of the SQLite library. Depending 8668 ** on how the SQLite library is compiled, this interface might not exist. 8669 ** 8670 ** The details of the operation codes, their meanings, the parameters 8671 ** they take, and what they do are all subject to change without notice. 8672 ** Unlike most of the SQLite API, this function is not guaranteed to 8673 ** operate consistently from one release to the next. 8674 */ 8675 SQLITE_API int sqlite3_test_control(int op, ...); 8676 8677 /* 8678 ** CAPI3REF: Testing Interface Operation Codes 8679 ** 8680 ** These constants are the valid operation code parameters used 8681 ** as the first argument to [sqlite3_test_control()]. 8682 ** 8683 ** These parameters and their meanings are subject to change 8684 ** without notice. These values are for testing purposes only. 8685 ** Applications should not use any of these parameters or the 8686 ** [sqlite3_test_control()] interface. 8687 */ 8688 #define SQLITE_TESTCTRL_FIRST 5 8689 #define SQLITE_TESTCTRL_PRNG_SAVE 5 8690 #define SQLITE_TESTCTRL_PRNG_RESTORE 6 8691 #define SQLITE_TESTCTRL_PRNG_RESET 7 /* NOT USED */ 8692 #define SQLITE_TESTCTRL_FK_NO_ACTION 7 8693 #define SQLITE_TESTCTRL_BITVEC_TEST 8 8694 #define SQLITE_TESTCTRL_FAULT_INSTALL 9 8695 #define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10 8696 #define SQLITE_TESTCTRL_PENDING_BYTE 11 8697 #define SQLITE_TESTCTRL_ASSERT 12 8698 #define SQLITE_TESTCTRL_ALWAYS 13 8699 #define SQLITE_TESTCTRL_RESERVE 14 /* NOT USED */ 8700 #define SQLITE_TESTCTRL_JSON_SELFCHECK 14 8701 #define SQLITE_TESTCTRL_OPTIMIZATIONS 15 8702 #define SQLITE_TESTCTRL_ISKEYWORD 16 /* NOT USED */ 8703 #define SQLITE_TESTCTRL_GETOPT 16 8704 #define SQLITE_TESTCTRL_SCRATCHMALLOC 17 /* NOT USED */ 8705 #define SQLITE_TESTCTRL_INTERNAL_FUNCTIONS 17 8706 #define SQLITE_TESTCTRL_LOCALTIME_FAULT 18 8707 #define SQLITE_TESTCTRL_EXPLAIN_STMT 19 /* NOT USED */ 8708 #define SQLITE_TESTCTRL_ONCE_RESET_THRESHOLD 19 8709 #define SQLITE_TESTCTRL_NEVER_CORRUPT 20 8710 #define SQLITE_TESTCTRL_VDBE_COVERAGE 21 8711 #define SQLITE_TESTCTRL_BYTEORDER 22 8712 #define SQLITE_TESTCTRL_ISINIT 23 8713 #define SQLITE_TESTCTRL_SORTER_MMAP 24 8714 #define SQLITE_TESTCTRL_IMPOSTER 25 8715 #define SQLITE_TESTCTRL_PARSER_COVERAGE 26 8716 #define SQLITE_TESTCTRL_RESULT_INTREAL 27 8717 #define SQLITE_TESTCTRL_PRNG_SEED 28 8718 #define SQLITE_TESTCTRL_EXTRA_SCHEMA_CHECKS 29 8719 #define SQLITE_TESTCTRL_SEEK_COUNT 30 8720 #define SQLITE_TESTCTRL_TRACEFLAGS 31 8721 #define SQLITE_TESTCTRL_TUNE 32 8722 #define SQLITE_TESTCTRL_LOGEST 33 8723 #define SQLITE_TESTCTRL_USELONGDOUBLE 34 /* NOT USED */ 8724 #define SQLITE_TESTCTRL_ATOF 34 8725 #define SQLITE_TESTCTRL_LAST 34 /* Largest TESTCTRL */ 8726 8727 /* 8728 ** CAPI3REF: SQL Keyword Checking 8729 ** 8730 ** These routines provide access to the set of SQL language keywords 8731 ** recognized by SQLite. Applications can use these routines to determine 8732 ** whether or not a specific identifier needs to be escaped (for example, 8733 ** by enclosing in double-quotes) so as not to confuse the parser. 8734 ** 8735 ** The sqlite3_keyword_count() interface returns the number of distinct 8736 ** keywords understood by SQLite. 8737 ** 8738 ** The sqlite3_keyword_name(N,Z,L) interface finds the 0-based N-th keyword and 8739 ** makes *Z point to that keyword expressed as UTF8 and writes the number 8740 ** of bytes in the keyword into *L. The string that *Z points to is not 8741 ** zero-terminated. The sqlite3_keyword_name(N,Z,L) routine returns 8742 ** SQLITE_OK if N is within bounds and SQLITE_ERROR if not. If either Z 8743 ** or L are NULL or invalid pointers then calls to 8744 ** sqlite3_keyword_name(N,Z,L) result in undefined behavior. 8745 ** 8746 ** The sqlite3_keyword_check(Z,L) interface checks to see whether or not 8747 ** the L-byte UTF8 identifier that Z points to is a keyword, returning non-zero 8748 ** if it is and zero if not. 8749 ** 8750 ** The parser used by SQLite is forgiving. It is often possible to use 8751 ** a keyword as an identifier as long as such use does not result in a 8752 ** parsing ambiguity. For example, the statement 8753 ** "CREATE TABLE BEGIN(REPLACE,PRAGMA,END);" is accepted by SQLite, and 8754 ** creates a new table named "BEGIN" with three columns named 8755 ** "REPLACE", "PRAGMA", and "END". Nevertheless, best practice is to avoid 8756 ** using keywords as identifiers. Common techniques used to avoid keyword 8757 ** name collisions include: 8758 ** <ul> 8759 ** <li> Put all identifier names inside double-quotes. This is the official 8760 ** SQL way to escape identifier names. 8761 ** <li> Put identifier names inside [...]. This is not standard SQL, 8762 ** but it is what SQL Server does and so lots of programmers use this 8763 ** technique. 8764 ** <li> Begin every identifier with the letter "Z" as no SQL keywords start 8765 ** with "Z". 8766 ** <li> Include a digit somewhere in every identifier name. 8767 ** </ul> 8768 ** 8769 ** Note that the number of keywords understood by SQLite can depend on 8770 ** compile-time options. For example, "VACUUM" is not a keyword if 8771 ** SQLite is compiled with the [-DSQLITE_OMIT_VACUUM] option. Also, 8772 ** new keywords may be added to future releases of SQLite. 8773 */ 8774 SQLITE_API int sqlite3_keyword_count(void); 8775 SQLITE_API int sqlite3_keyword_name(int,const char**,int*); 8776 SQLITE_API int sqlite3_keyword_check(const char*,int); 8777 8778 /* 8779 ** CAPI3REF: Dynamic String Object 8780 ** KEYWORDS: {dynamic string} 8781 ** 8782 ** An instance of the sqlite3_str object contains a dynamically-sized 8783 ** string under construction. 8784 ** 8785 ** The lifecycle of an sqlite3_str object is as follows: 8786 ** <ol> 8787 ** <li> ^The sqlite3_str object is created using [sqlite3_str_new()]. 8788 ** <li> ^Text is appended to the sqlite3_str object using various 8789 ** methods, such as [sqlite3_str_appendf()]. 8790 ** <li> ^The sqlite3_str object is destroyed and the string it created 8791 ** is returned using the [sqlite3_str_finish()] interface. 8792 ** </ol> 8793 */ 8794 typedef struct sqlite3_str sqlite3_str; 8795 8796 /* 8797 ** CAPI3REF: Create A New Dynamic String Object 8798 ** CONSTRUCTOR: sqlite3_str 8799 ** 8800 ** ^The [sqlite3_str_new(D)] interface allocates and initializes 8801 ** a new [sqlite3_str] object. To avoid memory leaks, the object returned by 8802 ** [sqlite3_str_new()] must be freed by a subsequent call to 8803 ** [sqlite3_str_finish(X)]. 8804 ** 8805 ** ^The [sqlite3_str_new(D)] interface always returns a pointer to a 8806 ** valid [sqlite3_str] object, though in the event of an out-of-memory 8807 ** error the returned object might be a special singleton that will 8808 ** silently reject new text, always return SQLITE_NOMEM from 8809 ** [sqlite3_str_errcode()], always return 0 for 8810 ** [sqlite3_str_length()], and always return NULL from 8811 ** [sqlite3_str_finish(X)]. It is always safe to use the value 8812 ** returned by [sqlite3_str_new(D)] as the sqlite3_str parameter 8813 ** to any of the other [sqlite3_str] methods. 8814 ** 8815 ** The D parameter to [sqlite3_str_new(D)] may be NULL. If the 8816 ** D parameter in [sqlite3_str_new(D)] is not NULL, then the maximum 8817 ** length of the string contained in the [sqlite3_str] object will be 8818 ** the value set for [sqlite3_limit](D,[SQLITE_LIMIT_LENGTH]) instead 8819 ** of [SQLITE_MAX_LENGTH]. 8820 */ 8821 SQLITE_API sqlite3_str *sqlite3_str_new(sqlite3*); 8822 8823 /* 8824 ** CAPI3REF: Finalize A Dynamic String 8825 ** DESTRUCTOR: sqlite3_str 8826 ** 8827 ** ^The [sqlite3_str_finish(X)] interface destroys the sqlite3_str object X 8828 ** and returns a pointer to a memory buffer obtained from [sqlite3_malloc64()] 8829 ** that contains the constructed string. The calling application should 8830 ** pass the returned value to [sqlite3_free()] to avoid a memory leak. 8831 ** ^The [sqlite3_str_finish(X)] interface may return a NULL pointer if any 8832 ** errors were encountered during construction of the string. ^The 8833 ** [sqlite3_str_finish(X)] interface might also return a NULL pointer if the 8834 ** string in [sqlite3_str] object X is zero bytes long. 8835 ** 8836 ** ^The [sqlite3_str_free(X)] interface destroys both the sqlite3_str object 8837 ** X and the string content it contains. Calling sqlite3_str_free(X) is 8838 ** the equivalent of calling [sqlite3_free](sqlite3_str_finish(X)). 8839 */ 8840 SQLITE_API char *sqlite3_str_finish(sqlite3_str*); 8841 SQLITE_API void sqlite3_str_free(sqlite3_str*); 8842 8843 /* 8844 ** CAPI3REF: Add Content To A Dynamic String 8845 ** METHOD: sqlite3_str 8846 ** 8847 ** These interfaces add or remove content to an sqlite3_str object 8848 ** previously obtained from [sqlite3_str_new()]. 8849 ** 8850 ** ^The [sqlite3_str_appendf(X,F,...)] and 8851 ** [sqlite3_str_vappendf(X,F,V)] interfaces uses the [built-in printf] 8852 ** functionality of SQLite to append formatted text onto the end of 8853 ** [sqlite3_str] object X. 8854 ** 8855 ** ^The [sqlite3_str_append(X,S,N)] method appends exactly N bytes from string S 8856 ** onto the end of the [sqlite3_str] object X. N must be non-negative. 8857 ** S must contain at least N non-zero bytes of content. To append a 8858 ** zero-terminated string in its entirety, use the [sqlite3_str_appendall()] 8859 ** method instead. 8860 ** 8861 ** ^The [sqlite3_str_appendall(X,S)] method appends the complete content of 8862 ** zero-terminated string S onto the end of [sqlite3_str] object X. 8863 ** 8864 ** ^The [sqlite3_str_appendchar(X,N,C)] method appends N copies of the 8865 ** single-byte character C onto the end of [sqlite3_str] object X. 8866 ** ^This method can be used, for example, to add whitespace indentation. 8867 ** 8868 ** ^The [sqlite3_str_reset(X)] method resets the string under construction 8869 ** inside [sqlite3_str] object X back to zero bytes in length. 8870 ** 8871 ** ^The [sqlite3_str_truncate(X,N)] method changes the length of the string 8872 ** under construction to be N bytes or less. This routine is a no-op if 8873 ** N is negative or if the string is already N bytes or smaller in size. 8874 ** 8875 ** These methods do not return a result code. ^If an error occurs, that fact 8876 ** is recorded in the [sqlite3_str] object and can be recovered by a 8877 ** subsequent call to [sqlite3_str_errcode(X)]. 8878 */ 8879 SQLITE_API void sqlite3_str_appendf(sqlite3_str*, const char *zFormat, ...); 8880 SQLITE_API void sqlite3_str_vappendf(sqlite3_str*, const char *zFormat, va_list); 8881 SQLITE_API void sqlite3_str_append(sqlite3_str*, const char *zIn, int N); 8882 SQLITE_API void sqlite3_str_appendall(sqlite3_str*, const char *zIn); 8883 SQLITE_API void sqlite3_str_appendchar(sqlite3_str*, int N, char C); 8884 SQLITE_API void sqlite3_str_reset(sqlite3_str*); 8885 SQLITE_API void sqlite3_str_truncate(sqlite3_str*,int N); 8886 8887 /* 8888 ** CAPI3REF: Status Of A Dynamic String 8889 ** METHOD: sqlite3_str 8890 ** 8891 ** These interfaces return the current status of an [sqlite3_str] object. 8892 ** 8893 ** ^If any prior errors have occurred while constructing the dynamic string 8894 ** in sqlite3_str X, then the [sqlite3_str_errcode(X)] method will return 8895 ** an appropriate error code. ^The [sqlite3_str_errcode(X)] method returns 8896 ** [SQLITE_NOMEM] following any out-of-memory error, or 8897 ** [SQLITE_TOOBIG] if the size of the dynamic string exceeds 8898 ** [SQLITE_MAX_LENGTH], or [SQLITE_OK] if there have been no errors. 8899 ** 8900 ** ^The [sqlite3_str_length(X)] method returns the current length, in bytes, 8901 ** of the dynamic string under construction in [sqlite3_str] object X. 8902 ** ^The length returned by [sqlite3_str_length(X)] does not include the 8903 ** zero-termination byte. 8904 ** 8905 ** ^The [sqlite3_str_value(X)] method returns a pointer to the current 8906 ** content of the dynamic string under construction in X. The value 8907 ** returned by [sqlite3_str_value(X)] is managed by the sqlite3_str object X 8908 ** and might be freed or altered by any subsequent method on the same 8909 ** [sqlite3_str] object. Applications must not use the pointer returned by 8910 ** [sqlite3_str_value(X)] after any subsequent method call on the same 8911 ** object. ^Applications may change the content of the string returned 8912 ** by [sqlite3_str_value(X)] as long as they do not write into any bytes 8913 ** outside the range of 0 to [sqlite3_str_length(X)] and do not read or 8914 ** write any byte after any subsequent sqlite3_str method call. 8915 */ 8916 SQLITE_API int sqlite3_str_errcode(sqlite3_str*); 8917 SQLITE_API int sqlite3_str_length(sqlite3_str*); 8918 SQLITE_API char *sqlite3_str_value(sqlite3_str*); 8919 8920 /* 8921 ** CAPI3REF: SQLite Runtime Status 8922 ** 8923 ** ^These interfaces are used to retrieve runtime status information 8924 ** about the performance of SQLite, and optionally to reset various 8925 ** highwater marks. ^The first argument is an integer code for 8926 ** the specific parameter to measure. ^(Recognized integer codes 8927 ** are of the form [status parameters | SQLITE_STATUS_...].)^ 8928 ** ^The current value of the parameter is returned into *pCurrent. 8929 ** ^The highest recorded value is returned in *pHighwater. ^If the 8930 ** resetFlag is true, then the highest record value is reset after 8931 ** *pHighwater is written. ^(Some parameters do not record the highest 8932 ** value. For those parameters 8933 ** nothing is written into *pHighwater and the resetFlag is ignored.)^ 8934 ** ^(Other parameters record only the highwater mark and not the current 8935 ** value. For these latter parameters nothing is written into *pCurrent.)^ 8936 ** 8937 ** ^The sqlite3_status() and sqlite3_status64() routines return 8938 ** SQLITE_OK on success and a non-zero [error code] on failure. 8939 ** 8940 ** If either the current value or the highwater mark is too large to 8941 ** be represented by a 32-bit integer, then the values returned by 8942 ** sqlite3_status() are undefined. 8943 ** 8944 ** See also: [sqlite3_db_status()] 8945 */ 8946 SQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag); 8947 SQLITE_API int sqlite3_status64( 8948 int op, 8949 sqlite3_int64 *pCurrent, 8950 sqlite3_int64 *pHighwater, 8951 int resetFlag 8952 ); 8953 8954 8955 /* 8956 ** CAPI3REF: Status Parameters 8957 ** KEYWORDS: {status parameters} 8958 ** 8959 ** These integer constants designate various run-time status parameters 8960 ** that can be returned by [sqlite3_status()]. 8961 ** 8962 ** <dl> 8963 ** [[SQLITE_STATUS_MEMORY_USED]] ^(<dt>SQLITE_STATUS_MEMORY_USED</dt> 8964 ** <dd>This parameter is the current amount of memory checked out 8965 ** using [sqlite3_malloc()], either directly or indirectly. The 8966 ** figure includes calls made to [sqlite3_malloc()] by the application 8967 ** and internal memory usage by the SQLite library. Auxiliary page-cache 8968 ** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in 8969 ** this parameter. The amount returned is the sum of the allocation 8970 ** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^ 8971 ** 8972 ** [[SQLITE_STATUS_MALLOC_SIZE]] ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt> 8973 ** <dd>This parameter records the largest memory allocation request 8974 ** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their 8975 ** internal equivalents). Only the value returned in the 8976 ** *pHighwater parameter to [sqlite3_status()] is of interest. 8977 ** The value written into the *pCurrent parameter is undefined.</dd>)^ 8978 ** 8979 ** [[SQLITE_STATUS_MALLOC_COUNT]] ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt> 8980 ** <dd>This parameter records the number of separate memory allocations 8981 ** currently checked out.</dd>)^ 8982 ** 8983 ** [[SQLITE_STATUS_PAGECACHE_USED]] ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt> 8984 ** <dd>This parameter returns the number of pages used out of the 8985 ** [pagecache memory allocator] that was configured using 8986 ** [SQLITE_CONFIG_PAGECACHE]. The 8987 ** value returned is in pages, not in bytes.</dd>)^ 8988 ** 8989 ** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]] 8990 ** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt> 8991 ** <dd>This parameter returns the number of bytes of page cache 8992 ** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE] 8993 ** buffer and where forced to overflow to [sqlite3_malloc()]. The 8994 ** returned value includes allocations that overflowed because they 8995 ** were too large (they were larger than the "sz" parameter to 8996 ** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because 8997 ** no space was left in the page cache.</dd>)^ 8998 ** 8999 ** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt> 9000 ** <dd>This parameter records the largest memory allocation request 9001 ** handed to the [pagecache memory allocator]. Only the value returned in the 9002 ** *pHighwater parameter to [sqlite3_status()] is of interest. 9003 ** The value written into the *pCurrent parameter is undefined.</dd>)^ 9004 ** 9005 ** [[SQLITE_STATUS_SCRATCH_USED]] <dt>SQLITE_STATUS_SCRATCH_USED</dt> 9006 ** <dd>No longer used.</dd> 9007 ** 9008 ** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt> 9009 ** <dd>No longer used.</dd> 9010 ** 9011 ** [[SQLITE_STATUS_SCRATCH_SIZE]] <dt>SQLITE_STATUS_SCRATCH_SIZE</dt> 9012 ** <dd>No longer used.</dd> 9013 ** 9014 ** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt> 9015 ** <dd>The *pHighwater parameter records the deepest parser stack. 9016 ** The *pCurrent value is undefined. The *pHighwater value is only 9017 ** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^ 9018 ** </dl> 9019 ** 9020 ** New status parameters may be added from time to time. 9021 */ 9022 #define SQLITE_STATUS_MEMORY_USED 0 9023 #define SQLITE_STATUS_PAGECACHE_USED 1 9024 #define SQLITE_STATUS_PAGECACHE_OVERFLOW 2 9025 #define SQLITE_STATUS_SCRATCH_USED 3 /* NOT USED */ 9026 #define SQLITE_STATUS_SCRATCH_OVERFLOW 4 /* NOT USED */ 9027 #define SQLITE_STATUS_MALLOC_SIZE 5 9028 #define SQLITE_STATUS_PARSER_STACK 6 9029 #define SQLITE_STATUS_PAGECACHE_SIZE 7 9030 #define SQLITE_STATUS_SCRATCH_SIZE 8 /* NOT USED */ 9031 #define SQLITE_STATUS_MALLOC_COUNT 9 9032 9033 /* 9034 ** CAPI3REF: Database Connection Status 9035 ** METHOD: sqlite3 9036 ** 9037 ** ^This interface is used to retrieve runtime status information 9038 ** about a single [database connection]. ^The first argument is the 9039 ** database connection object to be interrogated. ^The second argument 9040 ** is an integer constant, taken from the set of 9041 ** [SQLITE_DBSTATUS options], that 9042 ** determines the parameter to interrogate. The set of 9043 ** [SQLITE_DBSTATUS options] is likely 9044 ** to grow in future releases of SQLite. 9045 ** 9046 ** ^The current value of the requested parameter is written into *pCur 9047 ** and the highest instantaneous value is written into *pHiwtr. ^If 9048 ** the resetFlg is true, then the highest instantaneous value is 9049 ** reset back down to the current value. 9050 ** 9051 ** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a 9052 ** non-zero [error code] on failure. 9053 ** 9054 ** ^The sqlite3_db_status64(D,O,C,H,R) routine works exactly the same 9055 ** way as sqlite3_db_status(D,O,C,H,R) routine except that the C and H 9056 ** parameters are pointer to 64-bit integers (type: sqlite3_int64) instead 9057 ** of pointers to 32-bit integers, which allows larger status values 9058 ** to be returned. If a status value exceeds 2,147,483,647 then 9059 ** sqlite3_db_status() will truncate the value whereas sqlite3_db_status64() 9060 ** will return the full value. 9061 ** 9062 ** See also: [sqlite3_status()] and [sqlite3_stmt_status()]. 9063 */ 9064 SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg); 9065 SQLITE_API int sqlite3_db_status64(sqlite3*,int,sqlite3_int64*,sqlite3_int64*,int); 9066 9067 /* 9068 ** CAPI3REF: Status Parameters for database connections 9069 ** KEYWORDS: {SQLITE_DBSTATUS options} 9070 ** 9071 ** These constants are the available integer "verbs" that can be passed as 9072 ** the second argument to the [sqlite3_db_status()] interface. 9073 ** 9074 ** New verbs may be added in future releases of SQLite. Existing verbs 9075 ** might be discontinued. Applications should check the return code from 9076 ** [sqlite3_db_status()] to make sure that the call worked. 9077 ** The [sqlite3_db_status()] interface will return a non-zero error code 9078 ** if a discontinued or unsupported verb is invoked. 9079 ** 9080 ** <dl> 9081 ** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt> 9082 ** <dd>This parameter returns the number of lookaside memory slots currently 9083 ** checked out.</dd>)^ 9084 ** 9085 ** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_HIT</dt> 9086 ** <dd>This parameter returns the number of malloc attempts that were 9087 ** satisfied using lookaside memory. Only the high-water value is meaningful; 9088 ** the current value is always zero.</dd>)^ 9089 ** 9090 ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]] 9091 ** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE</dt> 9092 ** <dd>This parameter returns the number of malloc attempts that might have 9093 ** been satisfied using lookaside memory but failed due to the amount of 9094 ** memory requested being larger than the lookaside slot size. 9095 ** Only the high-water value is meaningful; 9096 ** the current value is always zero.</dd>)^ 9097 ** 9098 ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]] 9099 ** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL</dt> 9100 ** <dd>This parameter returns the number of malloc attempts that might have 9101 ** been satisfied using lookaside memory but failed due to all lookaside 9102 ** memory already being in use. 9103 ** Only the high-water value is meaningful; 9104 ** the current value is always zero.</dd>)^ 9105 ** 9106 ** [[SQLITE_DBSTATUS_CACHE_USED]] ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt> 9107 ** <dd>This parameter returns the approximate number of bytes of heap 9108 ** memory used by all pager caches associated with the database connection.)^ 9109 ** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0. 9110 ** </dd> 9111 ** 9112 ** [[SQLITE_DBSTATUS_CACHE_USED_SHARED]] 9113 ** ^(<dt>SQLITE_DBSTATUS_CACHE_USED_SHARED</dt> 9114 ** <dd>This parameter is similar to DBSTATUS_CACHE_USED, except that if a 9115 ** pager cache is shared between two or more connections the bytes of heap 9116 ** memory used by that pager cache is divided evenly between the attached 9117 ** connections.)^ In other words, if none of the pager caches associated 9118 ** with the database connection are shared, this request returns the same 9119 ** value as DBSTATUS_CACHE_USED. Or, if one or more of the pager caches are 9120 ** shared, the value returned by this call will be smaller than that returned 9121 ** by DBSTATUS_CACHE_USED. ^The highwater mark associated with 9122 ** SQLITE_DBSTATUS_CACHE_USED_SHARED is always 0.</dd> 9123 ** 9124 ** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt> 9125 ** <dd>This parameter returns the approximate number of bytes of heap 9126 ** memory used to store the schema for all databases associated 9127 ** with the connection - main, temp, and any [ATTACH]-ed databases.)^ 9128 ** ^The full amount of memory used by the schemas is reported, even if the 9129 ** schema memory is shared with other database connections due to 9130 ** [shared cache mode] being enabled. 9131 ** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0. 9132 ** </dd> 9133 ** 9134 ** [[SQLITE_DBSTATUS_STMT_USED]] ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt> 9135 ** <dd>This parameter returns the approximate number of bytes of heap 9136 ** and lookaside memory used by all prepared statements associated with 9137 ** the database connection.)^ 9138 ** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0. 9139 ** </dd> 9140 ** 9141 ** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(<dt>SQLITE_DBSTATUS_CACHE_HIT</dt> 9142 ** <dd>This parameter returns the number of pager cache hits that have 9143 ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT 9144 ** is always 0. 9145 ** </dd> 9146 ** 9147 ** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(<dt>SQLITE_DBSTATUS_CACHE_MISS</dt> 9148 ** <dd>This parameter returns the number of pager cache misses that have 9149 ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS 9150 ** is always 0. 9151 ** </dd> 9152 ** 9153 ** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(<dt>SQLITE_DBSTATUS_CACHE_WRITE</dt> 9154 ** <dd>This parameter returns the number of dirty cache entries that have 9155 ** been written to disk. Specifically, the number of pages written to the 9156 ** wal file in wal mode databases, or the number of pages written to the 9157 ** database file in rollback mode databases. Any pages written as part of 9158 ** transaction rollback or database recovery operations are not included. 9159 ** If an IO or other error occurs while writing a page to disk, the effect 9160 ** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The 9161 ** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0. 9162 ** <p> 9163 ** ^(There is overlap between the quantities measured by this parameter 9164 ** (SQLITE_DBSTATUS_CACHE_WRITE) and SQLITE_DBSTATUS_TEMPBUF_SPILL. 9165 ** Resetting one will reduce the other.)^ 9166 ** </dd> 9167 ** 9168 ** [[SQLITE_DBSTATUS_CACHE_SPILL]] ^(<dt>SQLITE_DBSTATUS_CACHE_SPILL</dt> 9169 ** <dd>This parameter returns the number of dirty cache entries that have 9170 ** been written to disk in the middle of a transaction due to the page 9171 ** cache overflowing. Transactions are more efficient if they are written 9172 ** to disk all at once. When pages spill mid-transaction, that introduces 9173 ** additional overhead. This parameter can be used to help identify 9174 ** inefficiencies that can be resolved by increasing the cache size. 9175 ** </dd> 9176 ** 9177 ** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(<dt>SQLITE_DBSTATUS_DEFERRED_FKS</dt> 9178 ** <dd>This parameter returns zero for the current value if and only if 9179 ** all foreign key constraints (deferred or immediate) have been 9180 ** resolved.)^ ^The highwater mark is always 0. 9181 ** 9182 ** [[SQLITE_DBSTATUS_TEMPBUF_SPILL] ^(<dt>SQLITE_DBSTATUS_TEMPBUF_SPILL</dt> 9183 ** <dd>^(This parameter returns the number of bytes written to temporary 9184 ** files on disk that could have been kept in memory had sufficient memory 9185 ** been available. This value includes writes to intermediate tables that 9186 ** are part of complex queries, external sorts that spill to disk, and 9187 ** writes to TEMP tables.)^ 9188 ** ^The highwater mark is always 0. 9189 ** <p> 9190 ** ^(There is overlap between the quantities measured by this parameter 9191 ** (SQLITE_DBSTATUS_TEMPBUF_SPILL) and SQLITE_DBSTATUS_CACHE_WRITE. 9192 ** Resetting one will reduce the other.)^ 9193 ** </dd> 9194 ** </dl> 9195 */ 9196 #define SQLITE_DBSTATUS_LOOKASIDE_USED 0 9197 #define SQLITE_DBSTATUS_CACHE_USED 1 9198 #define SQLITE_DBSTATUS_SCHEMA_USED 2 9199 #define SQLITE_DBSTATUS_STMT_USED 3 9200 #define SQLITE_DBSTATUS_LOOKASIDE_HIT 4 9201 #define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE 5 9202 #define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL 6 9203 #define SQLITE_DBSTATUS_CACHE_HIT 7 9204 #define SQLITE_DBSTATUS_CACHE_MISS 8 9205 #define SQLITE_DBSTATUS_CACHE_WRITE 9 9206 #define SQLITE_DBSTATUS_DEFERRED_FKS 10 9207 #define SQLITE_DBSTATUS_CACHE_USED_SHARED 11 9208 #define SQLITE_DBSTATUS_CACHE_SPILL 12 9209 #define SQLITE_DBSTATUS_TEMPBUF_SPILL 13 9210 #define SQLITE_DBSTATUS_MAX 13 /* Largest defined DBSTATUS */ 9211 9212 9213 /* 9214 ** CAPI3REF: Prepared Statement Status 9215 ** METHOD: sqlite3_stmt 9216 ** 9217 ** ^(Each prepared statement maintains various 9218 ** [SQLITE_STMTSTATUS counters] that measure the number 9219 ** of times it has performed specific operations.)^ These counters can 9220 ** be used to monitor the performance characteristics of the prepared 9221 ** statements. For example, if the number of table steps greatly exceeds 9222 ** the number of table searches or result rows, that would tend to indicate 9223 ** that the prepared statement is using a full table scan rather than 9224 ** an index. 9225 ** 9226 ** ^(This interface is used to retrieve and reset counter values from 9227 ** a [prepared statement]. The first argument is the prepared statement 9228 ** object to be interrogated. The second argument 9229 ** is an integer code for a specific [SQLITE_STMTSTATUS counter] 9230 ** to be interrogated.)^ 9231 ** ^The current value of the requested counter is returned. 9232 ** ^If the resetFlg is true, then the counter is reset to zero after this 9233 ** interface call returns. 9234 ** 9235 ** See also: [sqlite3_status()] and [sqlite3_db_status()]. 9236 */ 9237 SQLITE_API int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg); 9238 9239 /* 9240 ** CAPI3REF: Status Parameters for prepared statements 9241 ** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters} 9242 ** 9243 ** These preprocessor macros define integer codes that name counter 9244 ** values associated with the [sqlite3_stmt_status()] interface. 9245 ** The meanings of the various counters are as follows: 9246 ** 9247 ** <dl> 9248 ** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt> 9249 ** <dd>^This is the number of times that SQLite has stepped forward in 9250 ** a table as part of a full table scan. Large numbers for this counter 9251 ** may indicate opportunities for performance improvement through 9252 ** careful use of indices.</dd> 9253 ** 9254 ** [[SQLITE_STMTSTATUS_SORT]] <dt>SQLITE_STMTSTATUS_SORT</dt> 9255 ** <dd>^This is the number of sort operations that have occurred. 9256 ** A non-zero value in this counter may indicate an opportunity to 9257 ** improve performance through careful use of indices.</dd> 9258 ** 9259 ** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt> 9260 ** <dd>^This is the number of rows inserted into transient indices that 9261 ** were created automatically in order to help joins run faster. 9262 ** A non-zero value in this counter may indicate an opportunity to 9263 ** improve performance by adding permanent indices that do not 9264 ** need to be reinitialized each time the statement is run.</dd> 9265 ** 9266 ** [[SQLITE_STMTSTATUS_VM_STEP]] <dt>SQLITE_STMTSTATUS_VM_STEP</dt> 9267 ** <dd>^This is the number of virtual machine operations executed 9268 ** by the prepared statement if that number is less than or equal 9269 ** to 2147483647. The number of virtual machine operations can be 9270 ** used as a proxy for the total work done by the prepared statement. 9271 ** If the number of virtual machine operations exceeds 2147483647 9272 ** then the value returned by this statement status code is undefined.</dd> 9273 ** 9274 ** [[SQLITE_STMTSTATUS_REPREPARE]] <dt>SQLITE_STMTSTATUS_REPREPARE</dt> 9275 ** <dd>^This is the number of times that the prepare statement has been 9276 ** automatically regenerated due to schema changes or changes to 9277 ** [bound parameters] that might affect the query plan.</dd> 9278 ** 9279 ** [[SQLITE_STMTSTATUS_RUN]] <dt>SQLITE_STMTSTATUS_RUN</dt> 9280 ** <dd>^This is the number of times that the prepared statement has 9281 ** been run. A single "run" for the purposes of this counter is one 9282 ** or more calls to [sqlite3_step()] followed by a call to [sqlite3_reset()]. 9283 ** The counter is incremented on the first [sqlite3_step()] call of each 9284 ** cycle.</dd> 9285 ** 9286 ** [[SQLITE_STMTSTATUS_FILTER_MISS]] 9287 ** [[SQLITE_STMTSTATUS_FILTER HIT]] 9288 ** <dt>SQLITE_STMTSTATUS_FILTER_HIT<br> 9289 ** SQLITE_STMTSTATUS_FILTER_MISS</dt> 9290 ** <dd>^SQLITE_STMTSTATUS_FILTER_HIT is the number of times that a join 9291 ** step was bypassed because a Bloom filter returned not-found. The 9292 ** corresponding SQLITE_STMTSTATUS_FILTER_MISS value is the number of 9293 ** times that the Bloom filter returned a find, and thus the join step 9294 ** had to be processed as normal.</dd> 9295 ** 9296 ** [[SQLITE_STMTSTATUS_MEMUSED]] <dt>SQLITE_STMTSTATUS_MEMUSED</dt> 9297 ** <dd>^This is the approximate number of bytes of heap memory 9298 ** used to store the prepared statement. ^This value is not actually 9299 ** a counter, and so the resetFlg parameter to sqlite3_stmt_status() 9300 ** is ignored when the opcode is SQLITE_STMTSTATUS_MEMUSED. 9301 ** </dd> 9302 ** </dl> 9303 */ 9304 #define SQLITE_STMTSTATUS_FULLSCAN_STEP 1 9305 #define SQLITE_STMTSTATUS_SORT 2 9306 #define SQLITE_STMTSTATUS_AUTOINDEX 3 9307 #define SQLITE_STMTSTATUS_VM_STEP 4 9308 #define SQLITE_STMTSTATUS_REPREPARE 5 9309 #define SQLITE_STMTSTATUS_RUN 6 9310 #define SQLITE_STMTSTATUS_FILTER_MISS 7 9311 #define SQLITE_STMTSTATUS_FILTER_HIT 8 9312 #define SQLITE_STMTSTATUS_MEMUSED 99 9313 9314 /* 9315 ** CAPI3REF: Custom Page Cache Object 9316 ** 9317 ** The sqlite3_pcache type is opaque. It is implemented by 9318 ** the pluggable module. The SQLite core has no knowledge of 9319 ** its size or internal structure and never deals with the 9320 ** sqlite3_pcache object except by holding and passing pointers 9321 ** to the object. 9322 ** 9323 ** See [sqlite3_pcache_methods2] for additional information. 9324 */ 9325 typedef struct sqlite3_pcache sqlite3_pcache; 9326 9327 /* 9328 ** CAPI3REF: Custom Page Cache Object 9329 ** 9330 ** The sqlite3_pcache_page object represents a single page in the 9331 ** page cache. The page cache will allocate instances of this 9332 ** object. Various methods of the page cache use pointers to instances 9333 ** of this object as parameters or as their return value. 9334 ** 9335 ** See [sqlite3_pcache_methods2] for additional information. 9336 */ 9337 typedef struct sqlite3_pcache_page sqlite3_pcache_page; 9338 struct sqlite3_pcache_page { 9339 void *pBuf; /* The content of the page */ 9340 void *pExtra; /* Extra information associated with the page */ 9341 }; 9342 9343 /* 9344 ** CAPI3REF: Application Defined Page Cache. 9345 ** KEYWORDS: {page cache} 9346 ** 9347 ** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can 9348 ** register an alternative page cache implementation by passing in an 9349 ** instance of the sqlite3_pcache_methods2 structure.)^ 9350 ** In many applications, most of the heap memory allocated by 9351 ** SQLite is used for the page cache. 9352 ** By implementing a 9353 ** custom page cache using this API, an application can better control 9354 ** the amount of memory consumed by SQLite, the way in which 9355 ** that memory is allocated and released, and the policies used to 9356 ** determine exactly which parts of a database file are cached and for 9357 ** how long. 9358 ** 9359 ** The alternative page cache mechanism is an 9360 ** extreme measure that is only needed by the most demanding applications. 9361 ** The built-in page cache is recommended for most uses. 9362 ** 9363 ** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an 9364 ** internal buffer by SQLite within the call to [sqlite3_config]. Hence 9365 ** the application may discard the parameter after the call to 9366 ** [sqlite3_config()] returns.)^ 9367 ** 9368 ** [[the xInit() page cache method]] 9369 ** ^(The xInit() method is called once for each effective 9370 ** call to [sqlite3_initialize()])^ 9371 ** (usually only once during the lifetime of the process). ^(The xInit() 9372 ** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^ 9373 ** The intent of the xInit() method is to set up global data structures 9374 ** required by the custom page cache implementation. 9375 ** ^(If the xInit() method is NULL, then the 9376 ** built-in default page cache is used instead of the application defined 9377 ** page cache.)^ 9378 ** 9379 ** [[the xShutdown() page cache method]] 9380 ** ^The xShutdown() method is called by [sqlite3_shutdown()]. 9381 ** It can be used to clean up 9382 ** any outstanding resources before process shutdown, if required. 9383 ** ^The xShutdown() method may be NULL. 9384 ** 9385 ** ^SQLite automatically serializes calls to the xInit method, 9386 ** so the xInit method need not be threadsafe. ^The 9387 ** xShutdown method is only called from [sqlite3_shutdown()] so it does 9388 ** not need to be threadsafe either. All other methods must be threadsafe 9389 ** in multithreaded applications. 9390 ** 9391 ** ^SQLite will never invoke xInit() more than once without an intervening 9392 ** call to xShutdown(). 9393 ** 9394 ** [[the xCreate() page cache methods]] 9395 ** ^SQLite invokes the xCreate() method to construct a new cache instance. 9396 ** SQLite will typically create one cache instance for each open database file, 9397 ** though this is not guaranteed. ^The 9398 ** first parameter, szPage, is the size in bytes of the pages that must 9399 ** be allocated by the cache. ^szPage will always be a power of two. ^The 9400 ** second parameter szExtra is a number of bytes of extra storage 9401 ** associated with each page cache entry. ^The szExtra parameter will be 9402 ** a number less than 250. SQLite will use the 9403 ** extra szExtra bytes on each page to store metadata about the underlying 9404 ** database page on disk. The value passed into szExtra depends 9405 ** on the SQLite version, the target platform, and how SQLite was compiled. 9406 ** ^The third argument to xCreate(), bPurgeable, is true if the cache being 9407 ** created will be used to cache database pages of a file stored on disk, or 9408 ** false if it is used for an in-memory database. The cache implementation 9409 ** does not have to do anything special based upon the value of bPurgeable; 9410 ** it is purely advisory. ^On a cache where bPurgeable is false, SQLite will 9411 ** never invoke xUnpin() except to deliberately delete a page. 9412 ** ^In other words, calls to xUnpin() on a cache with bPurgeable set to 9413 ** false will always have the "discard" flag set to true. 9414 ** ^Hence, a cache created with bPurgeable set to false will 9415 ** never contain any unpinned pages. 9416 ** 9417 ** [[the xCachesize() page cache method]] 9418 ** ^(The xCachesize() method may be called at any time by SQLite to set the 9419 ** suggested maximum cache-size (number of pages stored) for the cache 9420 ** instance passed as the first argument. This is the value configured using 9421 ** the SQLite "[PRAGMA cache_size]" command.)^ As with the bPurgeable 9422 ** parameter, the implementation is not required to do anything with this 9423 ** value; it is advisory only. 9424 ** 9425 ** [[the xPagecount() page cache methods]] 9426 ** The xPagecount() method must return the number of pages currently 9427 ** stored in the cache, both pinned and unpinned. 9428 ** 9429 ** [[the xFetch() page cache methods]] 9430 ** The xFetch() method locates a page in the cache and returns a pointer to 9431 ** an sqlite3_pcache_page object associated with that page, or a NULL pointer. 9432 ** The pBuf element of the returned sqlite3_pcache_page object will be a 9433 ** pointer to a buffer of szPage bytes used to store the content of a 9434 ** single database page. The pExtra element of sqlite3_pcache_page will be 9435 ** a pointer to the szExtra bytes of extra storage that SQLite has requested 9436 ** for each entry in the page cache. 9437 ** 9438 ** The page to be fetched is determined by the key. ^The minimum key value 9439 ** is 1. After it has been retrieved using xFetch, the page is considered 9440 ** to be "pinned". 9441 ** 9442 ** If the requested page is already in the page cache, then the page cache 9443 ** implementation must return a pointer to the page buffer with its content 9444 ** intact. If the requested page is not already in the cache, then the 9445 ** cache implementation should use the value of the createFlag 9446 ** parameter to help it determine what action to take: 9447 ** 9448 ** <table border=1 width=85% align=center> 9449 ** <tr><th> createFlag <th> Behavior when page is not already in cache 9450 ** <tr><td> 0 <td> Do not allocate a new page. Return NULL. 9451 ** <tr><td> 1 <td> Allocate a new page if it is easy and convenient to do so. 9452 ** Otherwise return NULL. 9453 ** <tr><td> 2 <td> Make every effort to allocate a new page. Only return 9454 ** NULL if allocating a new page is effectively impossible. 9455 ** </table> 9456 ** 9457 ** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1. SQLite 9458 ** will only use a createFlag of 2 after a prior call with a createFlag of 1 9459 ** failed.)^ In between the xFetch() calls, SQLite may 9460 ** attempt to unpin one or more cache pages by spilling the content of 9461 ** pinned pages to disk and synching the operating system disk cache. 9462 ** 9463 ** [[the xUnpin() page cache method]] 9464 ** ^xUnpin() is called by SQLite with a pointer to a currently pinned page 9465 ** as its second argument. If the third parameter, discard, is non-zero, 9466 ** then the page must be evicted from the cache. 9467 ** ^If the discard parameter is 9468 ** zero, then the page may be discarded or retained at the discretion of the 9469 ** page cache implementation. ^The page cache implementation 9470 ** may choose to evict unpinned pages at any time. 9471 ** 9472 ** The cache must not perform any reference counting. A single 9473 ** call to xUnpin() unpins the page regardless of the number of prior calls 9474 ** to xFetch(). 9475 ** 9476 ** [[the xRekey() page cache methods]] 9477 ** The xRekey() method is used to change the key value associated with the 9478 ** page passed as the second argument. If the cache 9479 ** previously contains an entry associated with newKey, it must be 9480 ** discarded. ^Any prior cache entry associated with newKey is guaranteed not 9481 ** to be pinned. 9482 ** 9483 ** When SQLite calls the xTruncate() method, the cache must discard all 9484 ** existing cache entries with page numbers (keys) greater than or equal 9485 ** to the value of the iLimit parameter passed to xTruncate(). If any 9486 ** of these pages are pinned, they become implicitly unpinned, meaning that 9487 ** they can be safely discarded. 9488 ** 9489 ** [[the xDestroy() page cache method]] 9490 ** ^The xDestroy() method is used to delete a cache allocated by xCreate(). 9491 ** All resources associated with the specified cache should be freed. ^After 9492 ** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*] 9493 ** handle invalid, and will not use it with any other sqlite3_pcache_methods2 9494 ** functions. 9495 ** 9496 ** [[the xShrink() page cache method]] 9497 ** ^SQLite invokes the xShrink() method when it wants the page cache to 9498 ** free up as much of heap memory as possible. The page cache implementation 9499 ** is not obligated to free any memory, but well-behaved implementations should 9500 ** do their best. 9501 */ 9502 typedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2; 9503 struct sqlite3_pcache_methods2 { 9504 int iVersion; 9505 void *pArg; 9506 int (*xInit)(void*); 9507 void (*xShutdown)(void*); 9508 sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable); 9509 void (*xCachesize)(sqlite3_pcache*, int nCachesize); 9510 int (*xPagecount)(sqlite3_pcache*); 9511 sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag); 9512 void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard); 9513 void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*, 9514 unsigned oldKey, unsigned newKey); 9515 void (*xTruncate)(sqlite3_pcache*, unsigned iLimit); 9516 void (*xDestroy)(sqlite3_pcache*); 9517 void (*xShrink)(sqlite3_pcache*); 9518 }; 9519 9520 /* 9521 ** This is the obsolete pcache_methods object that has now been replaced 9522 ** by sqlite3_pcache_methods2. This object is not used by SQLite. It is 9523 ** retained in the header file for backwards compatibility only. 9524 */ 9525 typedef struct sqlite3_pcache_methods sqlite3_pcache_methods; 9526 struct sqlite3_pcache_methods { 9527 void *pArg; 9528 int (*xInit)(void*); 9529 void (*xShutdown)(void*); 9530 sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable); 9531 void (*xCachesize)(sqlite3_pcache*, int nCachesize); 9532 int (*xPagecount)(sqlite3_pcache*); 9533 void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag); 9534 void (*xUnpin)(sqlite3_pcache*, void*, int discard); 9535 void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey); 9536 void (*xTruncate)(sqlite3_pcache*, unsigned iLimit); 9537 void (*xDestroy)(sqlite3_pcache*); 9538 }; 9539 9540 9541 /* 9542 ** CAPI3REF: Online Backup Object 9543 ** 9544 ** The sqlite3_backup object records state information about an ongoing 9545 ** online backup operation. ^The sqlite3_backup object is created by 9546 ** a call to [sqlite3_backup_init()] and is destroyed by a call to 9547 ** [sqlite3_backup_finish()]. 9548 ** 9549 ** See Also: [Using the SQLite Online Backup API] 9550 */ 9551 typedef struct sqlite3_backup sqlite3_backup; 9552 9553 /* 9554 ** CAPI3REF: Online Backup API. 9555 ** 9556 ** The backup API copies the content of one database into another. 9557 ** It is useful either for creating backups of databases or 9558 ** for copying in-memory databases to or from persistent files. 9559 ** 9560 ** See Also: [Using the SQLite Online Backup API] 9561 ** 9562 ** ^SQLite holds a write transaction open on the destination database file 9563 ** for the duration of the backup operation. 9564 ** ^The source database is read-locked only while it is being read; 9565 ** it is not locked continuously for the entire backup operation. 9566 ** ^Thus, the backup may be performed on a live source database without 9567 ** preventing other database connections from 9568 ** reading or writing to the source database while the backup is underway. 9569 ** 9570 ** ^(To perform a backup operation: 9571 ** <ol> 9572 ** <li><b>sqlite3_backup_init()</b> is called once to initialize the 9573 ** backup, 9574 ** <li><b>sqlite3_backup_step()</b> is called one or more times to transfer 9575 ** the data between the two databases, and finally 9576 ** <li><b>sqlite3_backup_finish()</b> is called to release all resources 9577 ** associated with the backup operation. 9578 ** </ol>)^ 9579 ** There should be exactly one call to sqlite3_backup_finish() for each 9580 ** successful call to sqlite3_backup_init(). 9581 ** 9582 ** [[sqlite3_backup_init()]] <b>sqlite3_backup_init()</b> 9583 ** 9584 ** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the 9585 ** [database connection] associated with the destination database 9586 ** and the database name, respectively. 9587 ** ^The database name is "main" for the main database, "temp" for the 9588 ** temporary database, or the name specified after the AS keyword in 9589 ** an [ATTACH] statement for an attached database. 9590 ** ^The S and M arguments passed to 9591 ** sqlite3_backup_init(D,N,S,M) identify the [database connection] 9592 ** and database name of the source database, respectively. 9593 ** ^The source and destination [database connections] (parameters S and D) 9594 ** must be different or else sqlite3_backup_init(D,N,S,M) will fail with 9595 ** an error. 9596 ** 9597 ** ^A call to sqlite3_backup_init() will fail, returning NULL, if 9598 ** there is already a read or read-write transaction open on the 9599 ** destination database. 9600 ** 9601 ** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is 9602 ** returned and an error code and error message are stored in the 9603 ** destination [database connection] D. 9604 ** ^The error code and message for the failed call to sqlite3_backup_init() 9605 ** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or 9606 ** [sqlite3_errmsg16()] functions. 9607 ** ^A successful call to sqlite3_backup_init() returns a pointer to an 9608 ** [sqlite3_backup] object. 9609 ** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and 9610 ** sqlite3_backup_finish() functions to perform the specified backup 9611 ** operation. 9612 ** 9613 ** [[sqlite3_backup_step()]] <b>sqlite3_backup_step()</b> 9614 ** 9615 ** ^Function sqlite3_backup_step(B,N) will copy up to N pages between 9616 ** the source and destination databases specified by [sqlite3_backup] object B. 9617 ** ^If N is negative, all remaining source pages are copied. 9618 ** ^If sqlite3_backup_step(B,N) successfully copies N pages and there 9619 ** are still more pages to be copied, then the function returns [SQLITE_OK]. 9620 ** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages 9621 ** from source to destination, then it returns [SQLITE_DONE]. 9622 ** ^If an error occurs while running sqlite3_backup_step(B,N), 9623 ** then an [error code] is returned. ^As well as [SQLITE_OK] and 9624 ** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY], 9625 ** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an 9626 ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code. 9627 ** 9628 ** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if 9629 ** <ol> 9630 ** <li> the destination database was opened read-only, or 9631 ** <li> the destination database is using write-ahead-log journaling 9632 ** and the destination and source page sizes differ, or 9633 ** <li> the destination database is an in-memory database and the 9634 ** destination and source page sizes differ. 9635 ** </ol>)^ 9636 ** 9637 ** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then 9638 ** the [sqlite3_busy_handler | busy-handler function] 9639 ** is invoked (if one is specified). ^If the 9640 ** busy-handler returns non-zero before the lock is available, then 9641 ** [SQLITE_BUSY] is returned to the caller. ^In this case the call to 9642 ** sqlite3_backup_step() can be retried later. ^If the source 9643 ** [database connection] 9644 ** is being used to write to the source database when sqlite3_backup_step() 9645 ** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this 9646 ** case the call to sqlite3_backup_step() can be retried later on. ^(If 9647 ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or 9648 ** [SQLITE_READONLY] is returned, then 9649 ** there is no point in retrying the call to sqlite3_backup_step(). These 9650 ** errors are considered fatal.)^ The application must accept 9651 ** that the backup operation has failed and pass the backup operation handle 9652 ** to the sqlite3_backup_finish() to release associated resources. 9653 ** 9654 ** ^The first call to sqlite3_backup_step() obtains an exclusive lock 9655 ** on the destination file. ^The exclusive lock is not released until either 9656 ** sqlite3_backup_finish() is called or the backup operation is complete 9657 ** and sqlite3_backup_step() returns [SQLITE_DONE]. ^Every call to 9658 ** sqlite3_backup_step() obtains a [shared lock] on the source database that 9659 ** lasts for the duration of the sqlite3_backup_step() call. 9660 ** ^Because the source database is not locked between calls to 9661 ** sqlite3_backup_step(), the source database may be modified mid-way 9662 ** through the backup process. ^If the source database is modified by an 9663 ** external process or via a database connection other than the one being 9664 ** used by the backup operation, then the backup will be automatically 9665 ** restarted by the next call to sqlite3_backup_step(). ^If the source 9666 ** database is modified by using the same database connection as is used 9667 ** by the backup operation, then the backup database is automatically 9668 ** updated at the same time. 9669 ** 9670 ** [[sqlite3_backup_finish()]] <b>sqlite3_backup_finish()</b> 9671 ** 9672 ** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the 9673 ** application wishes to abandon the backup operation, the application 9674 ** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish(). 9675 ** ^The sqlite3_backup_finish() interfaces releases all 9676 ** resources associated with the [sqlite3_backup] object. 9677 ** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any 9678 ** active write-transaction on the destination database is rolled back. 9679 ** The [sqlite3_backup] object is invalid 9680 ** and may not be used following a call to sqlite3_backup_finish(). 9681 ** 9682 ** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no 9683 ** sqlite3_backup_step() errors occurred, regardless of whether or not 9684 ** sqlite3_backup_step() completed. 9685 ** ^If an out-of-memory condition or IO error occurred during any prior 9686 ** sqlite3_backup_step() call on the same [sqlite3_backup] object, then 9687 ** sqlite3_backup_finish() returns the corresponding [error code]. 9688 ** 9689 ** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step() 9690 ** is not a permanent error and does not affect the return value of 9691 ** sqlite3_backup_finish(). 9692 ** 9693 ** [[sqlite3_backup_remaining()]] [[sqlite3_backup_pagecount()]] 9694 ** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b> 9695 ** 9696 ** ^The sqlite3_backup_remaining() routine returns the number of pages still 9697 ** to be backed up at the conclusion of the most recent sqlite3_backup_step(). 9698 ** ^The sqlite3_backup_pagecount() routine returns the total number of pages 9699 ** in the source database at the conclusion of the most recent 9700 ** sqlite3_backup_step(). 9701 ** ^(The values returned by these functions are only updated by 9702 ** sqlite3_backup_step(). If the source database is modified in a way that 9703 ** changes the size of the source database or the number of pages remaining, 9704 ** those changes are not reflected in the output of sqlite3_backup_pagecount() 9705 ** and sqlite3_backup_remaining() until after the next 9706 ** sqlite3_backup_step().)^ 9707 ** 9708 ** <b>Concurrent Usage of Database Handles</b> 9709 ** 9710 ** ^The source [database connection] may be used by the application for other 9711 ** purposes while a backup operation is underway or being initialized. 9712 ** ^If SQLite is compiled and configured to support threadsafe database 9713 ** connections, then the source database connection may be used concurrently 9714 ** from within other threads. 9715 ** 9716 ** However, the application must guarantee that the destination 9717 ** [database connection] is not passed to any other API (by any thread) after 9718 ** sqlite3_backup_init() is called and before the corresponding call to 9719 ** sqlite3_backup_finish(). SQLite does not currently check to see 9720 ** if the application incorrectly accesses the destination [database connection] 9721 ** and so no error code is reported, but the operations may malfunction 9722 ** nevertheless. Use of the destination database connection while a 9723 ** backup is in progress might also cause a mutex deadlock. 9724 ** 9725 ** If running in [shared cache mode], the application must 9726 ** guarantee that the shared cache used by the destination database 9727 ** is not accessed while the backup is running. In practice this means 9728 ** that the application must guarantee that the disk file being 9729 ** backed up to is not accessed by any connection within the process, 9730 ** not just the specific connection that was passed to sqlite3_backup_init(). 9731 ** 9732 ** The [sqlite3_backup] object itself is partially threadsafe. Multiple 9733 ** threads may safely make multiple concurrent calls to sqlite3_backup_step(). 9734 ** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount() 9735 ** APIs are not strictly speaking threadsafe. If they are invoked at the 9736 ** same time as another thread is invoking sqlite3_backup_step() it is 9737 ** possible that they return invalid values. 9738 ** 9739 ** <b>Alternatives To Using The Backup API</b> 9740 ** 9741 ** Other techniques for safely creating a consistent backup of an SQLite 9742 ** database include: 9743 ** 9744 ** <ul> 9745 ** <li> The [VACUUM INTO] command. 9746 ** <li> The [sqlite3_rsync] utility program. 9747 ** </ul> 9748 */ 9749 SQLITE_API sqlite3_backup *sqlite3_backup_init( 9750 sqlite3 *pDest, /* Destination database handle */ 9751 const char *zDestName, /* Destination database name */ 9752 sqlite3 *pSource, /* Source database handle */ 9753 const char *zSourceName /* Source database name */ 9754 ); 9755 SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage); 9756 SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p); 9757 SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p); 9758 SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p); 9759 9760 /* 9761 ** CAPI3REF: Unlock Notification 9762 ** METHOD: sqlite3 9763 ** 9764 ** ^When running in shared-cache mode, a database operation may fail with 9765 ** an [SQLITE_LOCKED] error if the required locks on the shared-cache or 9766 ** individual tables within the shared-cache cannot be obtained. See 9767 ** [SQLite Shared-Cache Mode] for a description of shared-cache locking. 9768 ** ^This API may be used to register a callback that SQLite will invoke 9769 ** when the connection currently holding the required lock relinquishes it. 9770 ** ^This API is only available if the library was compiled with the 9771 ** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined. 9772 ** 9773 ** See Also: [Using the SQLite Unlock Notification Feature]. 9774 ** 9775 ** ^Shared-cache locks are released when a database connection concludes 9776 ** its current transaction, either by committing it or rolling it back. 9777 ** 9778 ** ^When a connection (known as the blocked connection) fails to obtain a 9779 ** shared-cache lock and SQLITE_LOCKED is returned to the caller, the 9780 ** identity of the database connection (the blocking connection) that 9781 ** has locked the required resource is stored internally. ^After an 9782 ** application receives an SQLITE_LOCKED error, it may call the 9783 ** sqlite3_unlock_notify() method with the blocked connection handle as 9784 ** the first argument to register for a callback that will be invoked 9785 ** when the blocking connection's current transaction is concluded. ^The 9786 ** callback is invoked from within the [sqlite3_step] or [sqlite3_close] 9787 ** call that concludes the blocking connection's transaction. 9788 ** 9789 ** ^(If sqlite3_unlock_notify() is called in a multi-threaded application, 9790 ** there is a chance that the blocking connection will have already 9791 ** concluded its transaction by the time sqlite3_unlock_notify() is invoked. 9792 ** If this happens, then the specified callback is invoked immediately, 9793 ** from within the call to sqlite3_unlock_notify().)^ 9794 ** 9795 ** ^If the blocked connection is attempting to obtain a write-lock on a 9796 ** shared-cache table, and more than one other connection currently holds 9797 ** a read-lock on the same table, then SQLite arbitrarily selects one of 9798 ** the other connections to use as the blocking connection. 9799 ** 9800 ** ^(There may be at most one unlock-notify callback registered by a 9801 ** blocked connection. If sqlite3_unlock_notify() is called when the 9802 ** blocked connection already has a registered unlock-notify callback, 9803 ** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is 9804 ** called with a NULL pointer as its second argument, then any existing 9805 ** unlock-notify callback is canceled. ^The blocked connection's 9806 ** unlock-notify callback may also be canceled by closing the blocked 9807 ** connection using [sqlite3_close()]. 9808 ** 9809 ** The unlock-notify callback is not reentrant. If an application invokes 9810 ** any sqlite3_xxx API functions from within an unlock-notify callback, a 9811 ** crash or deadlock may be the result. 9812 ** 9813 ** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always 9814 ** returns SQLITE_OK. 9815 ** 9816 ** <b>Callback Invocation Details</b> 9817 ** 9818 ** When an unlock-notify callback is registered, the application provides a 9819 ** single void* pointer that is passed to the callback when it is invoked. 9820 ** However, the signature of the callback function allows SQLite to pass 9821 ** it an array of void* context pointers. The first argument passed to 9822 ** an unlock-notify callback is a pointer to an array of void* pointers, 9823 ** and the second is the number of entries in the array. 9824 ** 9825 ** When a blocking connection's transaction is concluded, there may be 9826 ** more than one blocked connection that has registered for an unlock-notify 9827 ** callback. ^If two or more such blocked connections have specified the 9828 ** same callback function, then instead of invoking the callback function 9829 ** multiple times, it is invoked once with the set of void* context pointers 9830 ** specified by the blocked connections bundled together into an array. 9831 ** This gives the application an opportunity to prioritize any actions 9832 ** related to the set of unblocked database connections. 9833 ** 9834 ** <b>Deadlock Detection</b> 9835 ** 9836 ** Assuming that after registering for an unlock-notify callback a 9837 ** database waits for the callback to be issued before taking any further 9838 ** action (a reasonable assumption), then using this API may cause the 9839 ** application to deadlock. For example, if connection X is waiting for 9840 ** connection Y's transaction to be concluded, and similarly connection 9841 ** Y is waiting on connection X's transaction, then neither connection 9842 ** will proceed and the system may remain deadlocked indefinitely. 9843 ** 9844 ** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock 9845 ** detection. ^If a given call to sqlite3_unlock_notify() would put the 9846 ** system in a deadlocked state, then SQLITE_LOCKED is returned and no 9847 ** unlock-notify callback is registered. The system is said to be in 9848 ** a deadlocked state if connection A has registered for an unlock-notify 9849 ** callback on the conclusion of connection B's transaction, and connection 9850 ** B has itself registered for an unlock-notify callback when connection 9851 ** A's transaction is concluded. ^Indirect deadlock is also detected, so 9852 ** the system is also considered to be deadlocked if connection B has 9853 ** registered for an unlock-notify callback on the conclusion of connection 9854 ** C's transaction, where connection C is waiting on connection A. ^Any 9855 ** number of levels of indirection are allowed. 9856 ** 9857 ** <b>The "DROP TABLE" Exception</b> 9858 ** 9859 ** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost 9860 ** always appropriate to call sqlite3_unlock_notify(). There is however, 9861 ** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement, 9862 ** SQLite checks if there are any currently executing SELECT statements 9863 ** that belong to the same connection. If there are, SQLITE_LOCKED is 9864 ** returned. In this case there is no "blocking connection", so invoking 9865 ** sqlite3_unlock_notify() results in the unlock-notify callback being 9866 ** invoked immediately. If the application then re-attempts the "DROP TABLE" 9867 ** or "DROP INDEX" query, an infinite loop might be the result. 9868 ** 9869 ** One way around this problem is to check the extended error code returned 9870 ** by an sqlite3_step() call. ^(If there is a blocking connection, then the 9871 ** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in 9872 ** the special "DROP TABLE/INDEX" case, the extended error code is just 9873 ** SQLITE_LOCKED.)^ 9874 */ 9875 SQLITE_API int sqlite3_unlock_notify( 9876 sqlite3 *pBlocked, /* Waiting connection */ 9877 void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */ 9878 void *pNotifyArg /* Argument to pass to xNotify */ 9879 ); 9880 9881 9882 /* 9883 ** CAPI3REF: String Comparison 9884 ** 9885 ** ^The [sqlite3_stricmp()] and [sqlite3_strnicmp()] APIs allow applications 9886 ** and extensions to compare the contents of two buffers containing UTF-8 9887 ** strings in a case-independent fashion, using the same definition of "case 9888 ** independence" that SQLite uses internally when comparing identifiers. 9889 */ 9890 SQLITE_API int sqlite3_stricmp(const char *, const char *); 9891 SQLITE_API int sqlite3_strnicmp(const char *, const char *, int); 9892 9893 /* 9894 ** CAPI3REF: String Globbing 9895 * 9896 ** ^The [sqlite3_strglob(P,X)] interface returns zero if and only if 9897 ** string X matches the [GLOB] pattern P. 9898 ** ^The definition of [GLOB] pattern matching used in 9899 ** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the 9900 ** SQL dialect understood by SQLite. ^The [sqlite3_strglob(P,X)] function 9901 ** is case sensitive. 9902 ** 9903 ** Note that this routine returns zero on a match and non-zero if the strings 9904 ** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()]. 9905 ** 9906 ** See also: [sqlite3_strlike()]. 9907 */ 9908 SQLITE_API int sqlite3_strglob(const char *zGlob, const char *zStr); 9909 9910 /* 9911 ** CAPI3REF: String LIKE Matching 9912 * 9913 ** ^The [sqlite3_strlike(P,X,E)] interface returns zero if and only if 9914 ** string X matches the [LIKE] pattern P with escape character E. 9915 ** ^The definition of [LIKE] pattern matching used in 9916 ** [sqlite3_strlike(P,X,E)] is the same as for the "X LIKE P ESCAPE E" 9917 ** operator in the SQL dialect understood by SQLite. ^For "X LIKE P" without 9918 ** the ESCAPE clause, set the E parameter of [sqlite3_strlike(P,X,E)] to 0. 9919 ** ^As with the LIKE operator, the [sqlite3_strlike(P,X,E)] function is case 9920 ** insensitive - equivalent upper and lower case ASCII characters match 9921 ** one another. 9922 ** 9923 ** ^The [sqlite3_strlike(P,X,E)] function matches Unicode characters, though 9924 ** only ASCII characters are case folded. 9925 ** 9926 ** Note that this routine returns zero on a match and non-zero if the strings 9927 ** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()]. 9928 ** 9929 ** See also: [sqlite3_strglob()]. 9930 */ 9931 SQLITE_API int sqlite3_strlike(const char *zGlob, const char *zStr, unsigned int cEsc); 9932 9933 /* 9934 ** CAPI3REF: Error Logging Interface 9935 ** 9936 ** ^The [sqlite3_log()] interface writes a message into the [error log] 9937 ** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()]. 9938 ** ^If logging is enabled, the zFormat string and subsequent arguments are 9939 ** used with [sqlite3_snprintf()] to generate the final output string. 9940 ** 9941 ** The sqlite3_log() interface is intended for use by extensions such as 9942 ** virtual tables, collating functions, and SQL functions. While there is 9943 ** nothing to prevent an application from calling sqlite3_log(), doing so 9944 ** is considered bad form. 9945 ** 9946 ** The zFormat string must not be NULL. 9947 ** 9948 ** To avoid deadlocks and other threading problems, the sqlite3_log() routine 9949 ** will not use dynamically allocated memory. The log message is stored in 9950 ** a fixed-length buffer on the stack. If the log message is longer than 9951 ** a few hundred characters, it will be truncated to the length of the 9952 ** buffer. 9953 */ 9954 SQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...); 9955 9956 /* 9957 ** CAPI3REF: Write-Ahead Log Commit Hook 9958 ** METHOD: sqlite3 9959 ** 9960 ** ^The [sqlite3_wal_hook()] function is used to register a callback that 9961 ** is invoked each time data is committed to a database in wal mode. 9962 ** 9963 ** ^(The callback is invoked by SQLite after the commit has taken place and 9964 ** the associated write-lock on the database released)^, so the implementation 9965 ** may read, write or [checkpoint] the database as required. 9966 ** 9967 ** ^The first parameter passed to the callback function when it is invoked 9968 ** is a copy of the third parameter passed to sqlite3_wal_hook() when 9969 ** registering the callback. ^The second is a copy of the database handle. 9970 ** ^The third parameter is the name of the database that was written to - 9971 ** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter 9972 ** is the number of pages currently in the write-ahead log file, 9973 ** including those that were just committed. 9974 ** 9975 ** ^The callback function should normally return [SQLITE_OK]. ^If an error 9976 ** code is returned, that error will propagate back up through the 9977 ** SQLite code base to cause the statement that provoked the callback 9978 ** to report an error, though the commit will have still occurred. If the 9979 ** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value 9980 ** that does not correspond to any valid SQLite error code, the results 9981 ** are undefined. 9982 ** 9983 ** ^A single database handle may have at most a single write-ahead log 9984 ** callback registered at one time. ^Calling [sqlite3_wal_hook()] 9985 ** replaces the default behavior or previously registered write-ahead 9986 ** log callback. 9987 ** 9988 ** ^The return value is a copy of the third parameter from the 9989 ** previous call, if any, or 0. 9990 ** 9991 ** ^The [sqlite3_wal_autocheckpoint()] interface and the 9992 ** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and 9993 ** will overwrite any prior [sqlite3_wal_hook()] settings. 9994 ** 9995 ** ^If a write-ahead log callback is set using this function then 9996 ** [sqlite3_wal_checkpoint_v2()] or [PRAGMA wal_checkpoint] 9997 ** should be invoked periodically to keep the write-ahead log file 9998 ** from growing without bound. 9999 ** 10000 ** ^Passing a NULL pointer for the callback disables automatic 10001 ** checkpointing entirely. To re-enable the default behavior, call 10002 ** sqlite3_wal_autocheckpoint(db,1000) or use [PRAGMA wal_checkpoint]. 10003 */ 10004 SQLITE_API void *sqlite3_wal_hook( 10005 sqlite3*, 10006 int(*)(void *,sqlite3*,const char*,int), 10007 void* 10008 ); 10009 10010 /* 10011 ** CAPI3REF: Configure an auto-checkpoint 10012 ** METHOD: sqlite3 10013 ** 10014 ** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around 10015 ** [sqlite3_wal_hook()] that causes any database on [database connection] D 10016 ** to automatically [checkpoint] 10017 ** after committing a transaction if there are N or 10018 ** more frames in the [write-ahead log] file. ^Passing zero or 10019 ** a negative value as the N parameter disables automatic 10020 ** checkpoints entirely. 10021 ** 10022 ** ^The callback registered by this function replaces any existing callback 10023 ** registered using [sqlite3_wal_hook()]. ^Likewise, registering a callback 10024 ** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism 10025 ** configured by this function. 10026 ** 10027 ** ^The [wal_autocheckpoint pragma] can be used to invoke this interface 10028 ** from SQL. 10029 ** 10030 ** ^Checkpoints initiated by this mechanism are 10031 ** [sqlite3_wal_checkpoint_v2|PASSIVE]. 10032 ** 10033 ** ^Every new [database connection] defaults to having the auto-checkpoint 10034 ** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT] 10035 ** pages. 10036 ** 10037 ** ^The use of this interface is only necessary if the default setting 10038 ** is found to be suboptimal for a particular application. 10039 */ 10040 SQLITE_API int sqlite3_wal_autocheckpoint(sqlite3 *db, int N); 10041 10042 /* 10043 ** CAPI3REF: Checkpoint a database 10044 ** METHOD: sqlite3 10045 ** 10046 ** ^(The sqlite3_wal_checkpoint(D,X) is equivalent to 10047 ** [sqlite3_wal_checkpoint_v2](D,X,[SQLITE_CHECKPOINT_PASSIVE],0,0).)^ 10048 ** 10049 ** In brief, sqlite3_wal_checkpoint(D,X) causes the content in the 10050 ** [write-ahead log] for database X on [database connection] D to be 10051 ** transferred into the database file and for the write-ahead log to 10052 ** be reset. See the [checkpointing] documentation for addition 10053 ** information. 10054 ** 10055 ** This interface used to be the only way to cause a checkpoint to 10056 ** occur. But then the newer and more powerful [sqlite3_wal_checkpoint_v2()] 10057 ** interface was added. This interface is retained for backwards 10058 ** compatibility and as a convenience for applications that need to manually 10059 ** start a callback but which do not need the full power (and corresponding 10060 ** complication) of [sqlite3_wal_checkpoint_v2()]. 10061 */ 10062 SQLITE_API int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb); 10063 10064 /* 10065 ** CAPI3REF: Checkpoint a database 10066 ** METHOD: sqlite3 10067 ** 10068 ** ^(The sqlite3_wal_checkpoint_v2(D,X,M,L,C) interface runs a checkpoint 10069 ** operation on database X of [database connection] D in mode M. Status 10070 ** information is written back into integers pointed to by L and C.)^ 10071 ** ^(The M parameter must be a valid [checkpoint mode]:)^ 10072 ** 10073 ** <dl> 10074 ** <dt>SQLITE_CHECKPOINT_PASSIVE<dd> 10075 ** ^Checkpoint as many frames as possible without waiting for any database 10076 ** readers or writers to finish, then sync the database file if all frames 10077 ** in the log were checkpointed. ^The [busy-handler callback] 10078 ** is never invoked in the SQLITE_CHECKPOINT_PASSIVE mode. 10079 ** ^On the other hand, passive mode might leave the checkpoint unfinished 10080 ** if there are concurrent readers or writers. 10081 ** 10082 ** <dt>SQLITE_CHECKPOINT_FULL<dd> 10083 ** ^This mode blocks (it invokes the 10084 ** [sqlite3_busy_handler|busy-handler callback]) until there is no 10085 ** database writer and all readers are reading from the most recent database 10086 ** snapshot. ^It then checkpoints all frames in the log file and syncs the 10087 ** database file. ^This mode blocks new database writers while it is pending, 10088 ** but new database readers are allowed to continue unimpeded. 10089 ** 10090 ** <dt>SQLITE_CHECKPOINT_RESTART<dd> 10091 ** ^This mode works the same way as SQLITE_CHECKPOINT_FULL with the addition 10092 ** that after checkpointing the log file it blocks (calls the 10093 ** [busy-handler callback]) 10094 ** until all readers are reading from the database file only. ^This ensures 10095 ** that the next writer will restart the log file from the beginning. 10096 ** ^Like SQLITE_CHECKPOINT_FULL, this mode blocks new 10097 ** database writer attempts while it is pending, but does not impede readers. 10098 ** 10099 ** <dt>SQLITE_CHECKPOINT_TRUNCATE<dd> 10100 ** ^This mode works the same way as SQLITE_CHECKPOINT_RESTART with the 10101 ** addition that it also truncates the log file to zero bytes just prior 10102 ** to a successful return. 10103 ** 10104 ** <dt>SQLITE_CHECKPOINT_NOOP<dd> 10105 ** ^This mode always checkpoints zero frames. The only reason to invoke 10106 ** a NOOP checkpoint is to access the values returned by 10107 ** sqlite3_wal_checkpoint_v2() via output parameters *pnLog and *pnCkpt. 10108 ** </dl> 10109 ** 10110 ** ^If pnLog is not NULL, then *pnLog is set to the total number of frames in 10111 ** the log file or to -1 if the checkpoint could not run because 10112 ** of an error or because the database is not in [WAL mode]. ^If pnCkpt is not 10113 ** NULL,then *pnCkpt is set to the total number of checkpointed frames in the 10114 ** log file (including any that were already checkpointed before the function 10115 ** was called) or to -1 if the checkpoint could not run due to an error or 10116 ** because the database is not in WAL mode. ^Note that upon successful 10117 ** completion of an SQLITE_CHECKPOINT_TRUNCATE, the log file will have been 10118 ** truncated to zero bytes and so both *pnLog and *pnCkpt will be set to zero. 10119 ** 10120 ** ^All calls obtain an exclusive "checkpoint" lock on the database file. ^If 10121 ** any other process is running a checkpoint operation at the same time, the 10122 ** lock cannot be obtained and SQLITE_BUSY is returned. ^Even if there is a 10123 ** busy-handler configured, it will not be invoked in this case. 10124 ** 10125 ** ^The SQLITE_CHECKPOINT_FULL, RESTART and TRUNCATE modes also obtain the 10126 ** exclusive "writer" lock on the database file. ^If the writer lock cannot be 10127 ** obtained immediately, and a busy-handler is configured, it is invoked and 10128 ** the writer lock retried until either the busy-handler returns 0 or the lock 10129 ** is successfully obtained. ^The busy-handler is also invoked while waiting for 10130 ** database readers as described above. ^If the busy-handler returns 0 before 10131 ** the writer lock is obtained or while waiting for database readers, the 10132 ** checkpoint operation proceeds from that point in the same way as 10133 ** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible 10134 ** without blocking any further. ^SQLITE_BUSY is returned in this case. 10135 ** 10136 ** ^If parameter zDb is NULL or points to a zero length string, then the 10137 ** specified operation is attempted on all WAL databases [attached] to 10138 ** [database connection] db. In this case the 10139 ** values written to output parameters *pnLog and *pnCkpt are undefined. ^If 10140 ** an SQLITE_BUSY error is encountered when processing one or more of the 10141 ** attached WAL databases, the operation is still attempted on any remaining 10142 ** attached databases and SQLITE_BUSY is returned at the end. ^If any other 10143 ** error occurs while processing an attached database, processing is abandoned 10144 ** and the error code is returned to the caller immediately. ^If no error 10145 ** (SQLITE_BUSY or otherwise) is encountered while processing the attached 10146 ** databases, SQLITE_OK is returned. 10147 ** 10148 ** ^If database zDb is the name of an attached database that is not in WAL 10149 ** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. ^If 10150 ** zDb is not NULL (or a zero length string) and is not the name of any 10151 ** attached database, SQLITE_ERROR is returned to the caller. 10152 ** 10153 ** ^Unless it returns SQLITE_MISUSE, 10154 ** the sqlite3_wal_checkpoint_v2() interface 10155 ** sets the error information that is queried by 10156 ** [sqlite3_errcode()] and [sqlite3_errmsg()]. 10157 ** 10158 ** ^The [PRAGMA wal_checkpoint] command can be used to invoke this interface 10159 ** from SQL. 10160 */ 10161 SQLITE_API int sqlite3_wal_checkpoint_v2( 10162 sqlite3 *db, /* Database handle */ 10163 const char *zDb, /* Name of attached database (or NULL) */ 10164 int eMode, /* SQLITE_CHECKPOINT_* value */ 10165 int *pnLog, /* OUT: Size of WAL log in frames */ 10166 int *pnCkpt /* OUT: Total number of frames checkpointed */ 10167 ); 10168 10169 /* 10170 ** CAPI3REF: Checkpoint Mode Values 10171 ** KEYWORDS: {checkpoint mode} 10172 ** 10173 ** These constants define all valid values for the "checkpoint mode" passed 10174 ** as the third parameter to the [sqlite3_wal_checkpoint_v2()] interface. 10175 ** See the [sqlite3_wal_checkpoint_v2()] documentation for details on the 10176 ** meaning of each of these checkpoint modes. 10177 */ 10178 #define SQLITE_CHECKPOINT_NOOP -1 /* Do no work at all */ 10179 #define SQLITE_CHECKPOINT_PASSIVE 0 /* Do as much as possible w/o blocking */ 10180 #define SQLITE_CHECKPOINT_FULL 1 /* Wait for writers, then checkpoint */ 10181 #define SQLITE_CHECKPOINT_RESTART 2 /* Like FULL but wait for readers */ 10182 #define SQLITE_CHECKPOINT_TRUNCATE 3 /* Like RESTART but also truncate WAL */ 10183 10184 /* 10185 ** CAPI3REF: Virtual Table Interface Configuration 10186 ** 10187 ** This function may be called by either the [xConnect] or [xCreate] method 10188 ** of a [virtual table] implementation to configure 10189 ** various facets of the virtual table interface. 10190 ** 10191 ** If this interface is invoked outside the context of an xConnect or 10192 ** xCreate virtual table method then the behavior is undefined. 10193 ** 10194 ** In the call sqlite3_vtab_config(D,C,...) the D parameter is the 10195 ** [database connection] in which the virtual table is being created and 10196 ** which is passed in as the first argument to the [xConnect] or [xCreate] 10197 ** method that is invoking sqlite3_vtab_config(). The C parameter is one 10198 ** of the [virtual table configuration options]. The presence and meaning 10199 ** of parameters after C depend on which [virtual table configuration option] 10200 ** is used. 10201 */ 10202 SQLITE_API int sqlite3_vtab_config(sqlite3*, int op, ...); 10203 10204 /* 10205 ** CAPI3REF: Virtual Table Configuration Options 10206 ** KEYWORDS: {virtual table configuration options} 10207 ** KEYWORDS: {virtual table configuration option} 10208 ** 10209 ** These macros define the various options to the 10210 ** [sqlite3_vtab_config()] interface that [virtual table] implementations 10211 ** can use to customize and optimize their behavior. 10212 ** 10213 ** <dl> 10214 ** [[SQLITE_VTAB_CONSTRAINT_SUPPORT]] 10215 ** <dt>SQLITE_VTAB_CONSTRAINT_SUPPORT</dt> 10216 ** <dd>Calls of the form 10217 ** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported, 10218 ** where X is an integer. If X is zero, then the [virtual table] whose 10219 ** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not 10220 ** support constraints. In this configuration (which is the default) if 10221 ** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire 10222 ** statement is rolled back as if [ON CONFLICT | OR ABORT] had been 10223 ** specified as part of the user's SQL statement, regardless of the actual 10224 ** ON CONFLICT mode specified. 10225 ** 10226 ** If X is non-zero, then the virtual table implementation guarantees 10227 ** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before 10228 ** any modifications to internal or persistent data structures have been made. 10229 ** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite 10230 ** is able to roll back a statement or database transaction, and abandon 10231 ** or continue processing the current SQL statement as appropriate. 10232 ** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns 10233 ** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode 10234 ** had been ABORT. 10235 ** 10236 ** Virtual table implementations that are required to handle OR REPLACE 10237 ** must do so within the [xUpdate] method. If a call to the 10238 ** [sqlite3_vtab_on_conflict()] function indicates that the current ON 10239 ** CONFLICT policy is REPLACE, the virtual table implementation should 10240 ** silently replace the appropriate rows within the xUpdate callback and 10241 ** return SQLITE_OK. Or, if this is not possible, it may return 10242 ** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT 10243 ** constraint handling. 10244 ** </dd> 10245 ** 10246 ** [[SQLITE_VTAB_DIRECTONLY]]<dt>SQLITE_VTAB_DIRECTONLY</dt> 10247 ** <dd>Calls of the form 10248 ** [sqlite3_vtab_config](db,SQLITE_VTAB_DIRECTONLY) from within the 10249 ** the [xConnect] or [xCreate] methods of a [virtual table] implementation 10250 ** prohibits that virtual table from being used from within triggers and 10251 ** views. 10252 ** </dd> 10253 ** 10254 ** [[SQLITE_VTAB_INNOCUOUS]]<dt>SQLITE_VTAB_INNOCUOUS</dt> 10255 ** <dd>Calls of the form 10256 ** [sqlite3_vtab_config](db,SQLITE_VTAB_INNOCUOUS) from within the 10257 ** [xConnect] or [xCreate] methods of a [virtual table] implementation 10258 ** identify that virtual table as being safe to use from within triggers 10259 ** and views. Conceptually, the SQLITE_VTAB_INNOCUOUS tag means that the 10260 ** virtual table can do no serious harm even if it is controlled by a 10261 ** malicious hacker. Developers should avoid setting the SQLITE_VTAB_INNOCUOUS 10262 ** flag unless absolutely necessary. 10263 ** </dd> 10264 ** 10265 ** [[SQLITE_VTAB_USES_ALL_SCHEMAS]]<dt>SQLITE_VTAB_USES_ALL_SCHEMAS</dt> 10266 ** <dd>Calls of the form 10267 ** [sqlite3_vtab_config](db,SQLITE_VTAB_USES_ALL_SCHEMA) from within the 10268 ** the [xConnect] or [xCreate] methods of a [virtual table] implementation 10269 ** instruct the query planner to begin at least a read transaction on 10270 ** all schemas ("main", "temp", and any ATTACH-ed databases) whenever the 10271 ** virtual table is used. 10272 ** </dd> 10273 ** </dl> 10274 */ 10275 #define SQLITE_VTAB_CONSTRAINT_SUPPORT 1 10276 #define SQLITE_VTAB_INNOCUOUS 2 10277 #define SQLITE_VTAB_DIRECTONLY 3 10278 #define SQLITE_VTAB_USES_ALL_SCHEMAS 4 10279 10280 /* 10281 ** CAPI3REF: Determine The Virtual Table Conflict Policy 10282 ** 10283 ** This function may only be called from within a call to the [xUpdate] method 10284 ** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The 10285 ** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL], 10286 ** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode 10287 ** of the SQL statement that triggered the call to the [xUpdate] method of the 10288 ** [virtual table]. 10289 */ 10290 SQLITE_API int sqlite3_vtab_on_conflict(sqlite3 *); 10291 10292 /* 10293 ** CAPI3REF: Determine If Virtual Table Column Access Is For UPDATE 10294 ** 10295 ** If the sqlite3_vtab_nochange(X) routine is called within the [xColumn] 10296 ** method of a [virtual table], then it might return true if the 10297 ** column is being fetched as part of an UPDATE operation during which the 10298 ** column value will not change. The virtual table implementation can use 10299 ** this hint as permission to substitute a return value that is less 10300 ** expensive to compute and that the corresponding 10301 ** [xUpdate] method understands as a "no-change" value. 10302 ** 10303 ** If the [xColumn] method calls sqlite3_vtab_nochange() and finds that 10304 ** the column is not changed by the UPDATE statement, then the xColumn 10305 ** method can optionally return without setting a result, without calling 10306 ** any of the [sqlite3_result_int|sqlite3_result_xxxxx() interfaces]. 10307 ** In that case, [sqlite3_value_nochange(X)] will return true for the 10308 ** same column in the [xUpdate] method. 10309 ** 10310 ** The sqlite3_vtab_nochange() routine is an optimization. Virtual table 10311 ** implementations should continue to give a correct answer even if the 10312 ** sqlite3_vtab_nochange() interface were to always return false. In the 10313 ** current implementation, the sqlite3_vtab_nochange() interface does always 10314 ** returns false for the enhanced [UPDATE FROM] statement. 10315 */ 10316 SQLITE_API int sqlite3_vtab_nochange(sqlite3_context*); 10317 10318 /* 10319 ** CAPI3REF: Determine The Collation For a Virtual Table Constraint 10320 ** METHOD: sqlite3_index_info 10321 ** 10322 ** This function may only be called from within a call to the [xBestIndex] 10323 ** method of a [virtual table]. This function returns a pointer to a string 10324 ** that is the name of the appropriate collation sequence to use for text 10325 ** comparisons on the constraint identified by its arguments. 10326 ** 10327 ** The first argument must be the pointer to the [sqlite3_index_info] object 10328 ** that is the first parameter to the xBestIndex() method. The second argument 10329 ** must be an index into the aConstraint[] array belonging to the 10330 ** sqlite3_index_info structure passed to xBestIndex. 10331 ** 10332 ** Important: 10333 ** The first parameter must be the same pointer that is passed into the 10334 ** xBestMethod() method. The first parameter may not be a pointer to a 10335 ** different [sqlite3_index_info] object, even an exact copy. 10336 ** 10337 ** The return value is computed as follows: 10338 ** 10339 ** <ol> 10340 ** <li><p> If the constraint comes from a WHERE clause expression that contains 10341 ** a [COLLATE operator], then the name of the collation specified by 10342 ** that COLLATE operator is returned. 10343 ** <li><p> If there is no COLLATE operator, but the column that is the subject 10344 ** of the constraint specifies an alternative collating sequence via 10345 ** a [COLLATE clause] on the column definition within the CREATE TABLE 10346 ** statement that was passed into [sqlite3_declare_vtab()], then the 10347 ** name of that alternative collating sequence is returned. 10348 ** <li><p> Otherwise, "BINARY" is returned. 10349 ** </ol> 10350 */ 10351 SQLITE_API const char *sqlite3_vtab_collation(sqlite3_index_info*,int); 10352 10353 /* 10354 ** CAPI3REF: Determine if a virtual table query is DISTINCT 10355 ** METHOD: sqlite3_index_info 10356 ** 10357 ** This API may only be used from within an [xBestIndex|xBestIndex method] 10358 ** of a [virtual table] implementation. The result of calling this 10359 ** interface from outside of xBestIndex() is undefined and probably harmful. 10360 ** 10361 ** ^The sqlite3_vtab_distinct() interface returns an integer between 0 and 10362 ** 3. The integer returned by sqlite3_vtab_distinct() 10363 ** gives the virtual table additional information about how the query 10364 ** planner wants the output to be ordered. As long as the virtual table 10365 ** can meet the ordering requirements of the query planner, it may set 10366 ** the "orderByConsumed" flag. 10367 ** 10368 ** <ol><li value="0"><p> 10369 ** ^If the sqlite3_vtab_distinct() interface returns 0, that means 10370 ** that the query planner needs the virtual table to return all rows in the 10371 ** sort order defined by the "nOrderBy" and "aOrderBy" fields of the 10372 ** [sqlite3_index_info] object. This is the default expectation. If the 10373 ** virtual table outputs all rows in sorted order, then it is always safe for 10374 ** the xBestIndex method to set the "orderByConsumed" flag, regardless of 10375 ** the return value from sqlite3_vtab_distinct(). 10376 ** <li value="1"><p> 10377 ** ^(If the sqlite3_vtab_distinct() interface returns 1, that means 10378 ** that the query planner does not need the rows to be returned in sorted order 10379 ** as long as all rows with the same values in all columns identified by the 10380 ** "aOrderBy" field are adjacent.)^ This mode is used when the query planner 10381 ** is doing a GROUP BY. 10382 ** <li value="2"><p> 10383 ** ^(If the sqlite3_vtab_distinct() interface returns 2, that means 10384 ** that the query planner does not need the rows returned in any particular 10385 ** order, as long as rows with the same values in all columns identified 10386 ** by "aOrderBy" are adjacent.)^ ^(Furthermore, when two or more rows 10387 ** contain the same values for all columns identified by "colUsed", all but 10388 ** one such row may optionally be omitted from the result.)^ 10389 ** The virtual table is not required to omit rows that are duplicates 10390 ** over the "colUsed" columns, but if the virtual table can do that without 10391 ** too much extra effort, it could potentially help the query to run faster. 10392 ** This mode is used for a DISTINCT query. 10393 ** <li value="3"><p> 10394 ** ^(If the sqlite3_vtab_distinct() interface returns 3, that means the 10395 ** virtual table must return rows in the order defined by "aOrderBy" as 10396 ** if the sqlite3_vtab_distinct() interface had returned 0. However if 10397 ** two or more rows in the result have the same values for all columns 10398 ** identified by "colUsed", then all but one such row may optionally be 10399 ** omitted.)^ Like when the return value is 2, the virtual table 10400 ** is not required to omit rows that are duplicates over the "colUsed" 10401 ** columns, but if the virtual table can do that without 10402 ** too much extra effort, it could potentially help the query to run faster. 10403 ** This mode is used for queries 10404 ** that have both DISTINCT and ORDER BY clauses. 10405 ** </ol> 10406 ** 10407 ** <p>The following table summarizes the conditions under which the 10408 ** virtual table is allowed to set the "orderByConsumed" flag based on 10409 ** the value returned by sqlite3_vtab_distinct(). This table is a 10410 ** restatement of the previous four paragraphs: 10411 ** 10412 ** <table border=1 cellspacing=0 cellpadding=10 width="90%"> 10413 ** <tr> 10414 ** <td valign="top">sqlite3_vtab_distinct() return value 10415 ** <td valign="top">Rows are returned in aOrderBy order 10416 ** <td valign="top">Rows with the same value in all aOrderBy columns are 10417 ** adjacent 10418 ** <td valign="top">Duplicates over all colUsed columns may be omitted 10419 ** <tr><td>0<td>yes<td>yes<td>no 10420 ** <tr><td>1<td>no<td>yes<td>no 10421 ** <tr><td>2<td>no<td>yes<td>yes 10422 ** <tr><td>3<td>yes<td>yes<td>yes 10423 ** </table> 10424 ** 10425 ** ^For the purposes of comparing virtual table output values to see if the 10426 ** values are the same value for sorting purposes, two NULL values are 10427 ** considered to be the same. In other words, the comparison operator is "IS" 10428 ** (or "IS NOT DISTINCT FROM") and not "==". 10429 ** 10430 ** If a virtual table implementation is unable to meet the requirements 10431 ** specified above, then it must not set the "orderByConsumed" flag in the 10432 ** [sqlite3_index_info] object or an incorrect answer may result. 10433 ** 10434 ** ^A virtual table implementation is always free to return rows in any order 10435 ** it wants, as long as the "orderByConsumed" flag is not set. ^When the 10436 ** "orderByConsumed" flag is unset, the query planner will add extra 10437 ** [bytecode] to ensure that the final results returned by the SQL query are 10438 ** ordered correctly. The use of the "orderByConsumed" flag and the 10439 ** sqlite3_vtab_distinct() interface is merely an optimization. ^Careful 10440 ** use of the sqlite3_vtab_distinct() interface and the "orderByConsumed" 10441 ** flag might help queries against a virtual table to run faster. Being 10442 ** overly aggressive and setting the "orderByConsumed" flag when it is not 10443 ** valid to do so, on the other hand, might cause SQLite to return incorrect 10444 ** results. 10445 */ 10446 SQLITE_API int sqlite3_vtab_distinct(sqlite3_index_info*); 10447 10448 /* 10449 ** CAPI3REF: Identify and handle IN constraints in xBestIndex 10450 ** 10451 ** This interface may only be used from within an 10452 ** [xBestIndex|xBestIndex() method] of a [virtual table] implementation. 10453 ** The result of invoking this interface from any other context is 10454 ** undefined and probably harmful. 10455 ** 10456 ** ^(A constraint on a virtual table of the form 10457 ** "[IN operator|column IN (...)]" is 10458 ** communicated to the xBestIndex method as a 10459 ** [SQLITE_INDEX_CONSTRAINT_EQ] constraint.)^ If xBestIndex wants to use 10460 ** this constraint, it must set the corresponding 10461 ** aConstraintUsage[].argvIndex to a positive integer. ^(Then, under 10462 ** the usual mode of handling IN operators, SQLite generates [bytecode] 10463 ** that invokes the [xFilter|xFilter() method] once for each value 10464 ** on the right-hand side of the IN operator.)^ Thus the virtual table 10465 ** only sees a single value from the right-hand side of the IN operator 10466 ** at a time. 10467 ** 10468 ** In some cases, however, it would be advantageous for the virtual 10469 ** table to see all values on the right-hand of the IN operator all at 10470 ** once. The sqlite3_vtab_in() interfaces facilitates this in two ways: 10471 ** 10472 ** <ol> 10473 ** <li><p> 10474 ** ^A call to sqlite3_vtab_in(P,N,-1) will return true (non-zero) 10475 ** if and only if the [sqlite3_index_info|P->aConstraint][N] constraint 10476 ** is an [IN operator] that can be processed all at once. ^In other words, 10477 ** sqlite3_vtab_in() with -1 in the third argument is a mechanism 10478 ** by which the virtual table can ask SQLite if all-at-once processing 10479 ** of the IN operator is even possible. 10480 ** 10481 ** <li><p> 10482 ** ^A call to sqlite3_vtab_in(P,N,F) with F==1 or F==0 indicates 10483 ** to SQLite that the virtual table does or does not want to process 10484 ** the IN operator all-at-once, respectively. ^Thus when the third 10485 ** parameter (F) is non-negative, this interface is the mechanism by 10486 ** which the virtual table tells SQLite how it wants to process the 10487 ** IN operator. 10488 ** </ol> 10489 ** 10490 ** ^The sqlite3_vtab_in(P,N,F) interface can be invoked multiple times 10491 ** within the same xBestIndex method call. ^For any given P,N pair, 10492 ** the return value from sqlite3_vtab_in(P,N,F) will always be the same 10493 ** within the same xBestIndex call. ^If the interface returns true 10494 ** (non-zero), that means that the constraint is an IN operator 10495 ** that can be processed all-at-once. ^If the constraint is not an IN 10496 ** operator or cannot be processed all-at-once, then the interface returns 10497 ** false. 10498 ** 10499 ** ^(All-at-once processing of the IN operator is selected if both of the 10500 ** following conditions are met: 10501 ** 10502 ** <ol> 10503 ** <li><p> The P->aConstraintUsage[N].argvIndex value is set to a positive 10504 ** integer. This is how the virtual table tells SQLite that it wants to 10505 ** use the N-th constraint. 10506 ** 10507 ** <li><p> The last call to sqlite3_vtab_in(P,N,F) for which F was 10508 ** non-negative had F>=1. 10509 ** </ol>)^ 10510 ** 10511 ** ^If either or both of the conditions above are false, then SQLite uses 10512 ** the traditional one-at-a-time processing strategy for the IN constraint. 10513 ** ^If both conditions are true, then the argvIndex-th parameter to the 10514 ** xFilter method will be an [sqlite3_value] that appears to be NULL, 10515 ** but which can be passed to [sqlite3_vtab_in_first()] and 10516 ** [sqlite3_vtab_in_next()] to find all values on the right-hand side 10517 ** of the IN constraint. 10518 */ 10519 SQLITE_API int sqlite3_vtab_in(sqlite3_index_info*, int iCons, int bHandle); 10520 10521 /* 10522 ** CAPI3REF: Find all elements on the right-hand side of an IN constraint. 10523 ** 10524 ** These interfaces are only useful from within the 10525 ** [xFilter|xFilter() method] of a [virtual table] implementation. 10526 ** The result of invoking these interfaces from any other context 10527 ** is undefined and probably harmful. 10528 ** 10529 ** The X parameter in a call to sqlite3_vtab_in_first(X,P) or 10530 ** sqlite3_vtab_in_next(X,P) should be one of the parameters to the 10531 ** xFilter method which invokes these routines, and specifically 10532 ** a parameter that was previously selected for all-at-once IN constraint 10533 ** processing using the [sqlite3_vtab_in()] interface in the 10534 ** [xBestIndex|xBestIndex method]. ^(If the X parameter is not 10535 ** an xFilter argument that was selected for all-at-once IN constraint 10536 ** processing, then these routines return [SQLITE_ERROR].)^ 10537 ** 10538 ** ^(Use these routines to access all values on the right-hand side 10539 ** of the IN constraint using code like the following: 10540 ** 10541 ** <blockquote><pre> 10542 ** for(rc=sqlite3_vtab_in_first(pList, &pVal); 10543 ** rc==SQLITE_OK && pVal; 10544 ** rc=sqlite3_vtab_in_next(pList, &pVal) 10545 ** ){ 10546 ** // do something with pVal 10547 ** } 10548 ** if( rc!=SQLITE_DONE ){ 10549 ** // an error has occurred 10550 ** } 10551 ** </pre></blockquote>)^ 10552 ** 10553 ** ^On success, the sqlite3_vtab_in_first(X,P) and sqlite3_vtab_in_next(X,P) 10554 ** routines return SQLITE_OK and set *P to point to the first or next value 10555 ** on the RHS of the IN constraint. ^If there are no more values on the 10556 ** right hand side of the IN constraint, then *P is set to NULL and these 10557 ** routines return [SQLITE_DONE]. ^The return value might be 10558 ** some other value, such as SQLITE_NOMEM, in the event of a malfunction. 10559 ** 10560 ** The *ppOut values returned by these routines are only valid until the 10561 ** next call to either of these routines or until the end of the xFilter 10562 ** method from which these routines were called. If the virtual table 10563 ** implementation needs to retain the *ppOut values for longer, it must make 10564 ** copies. The *ppOut values are [protected sqlite3_value|protected]. 10565 */ 10566 SQLITE_API int sqlite3_vtab_in_first(sqlite3_value *pVal, sqlite3_value **ppOut); 10567 SQLITE_API int sqlite3_vtab_in_next(sqlite3_value *pVal, sqlite3_value **ppOut); 10568 10569 /* 10570 ** CAPI3REF: Constraint values in xBestIndex() 10571 ** METHOD: sqlite3_index_info 10572 ** 10573 ** This API may only be used from within the [xBestIndex|xBestIndex method] 10574 ** of a [virtual table] implementation. The result of calling this interface 10575 ** from outside of an xBestIndex method are undefined and probably harmful. 10576 ** 10577 ** ^When the sqlite3_vtab_rhs_value(P,J,V) interface is invoked from within 10578 ** the [xBestIndex] method of a [virtual table] implementation, with P being 10579 ** a copy of the [sqlite3_index_info] object pointer passed into xBestIndex and 10580 ** J being a 0-based index into P->aConstraint[], then this routine 10581 ** attempts to set *V to the value of the right-hand operand of 10582 ** that constraint if the right-hand operand is known. ^If the 10583 ** right-hand operand is not known, then *V is set to a NULL pointer. 10584 ** ^The sqlite3_vtab_rhs_value(P,J,V) interface returns SQLITE_OK if 10585 ** and only if *V is set to a value. ^The sqlite3_vtab_rhs_value(P,J,V) 10586 ** inteface returns SQLITE_NOTFOUND if the right-hand side of the J-th 10587 ** constraint is not available. ^The sqlite3_vtab_rhs_value() interface 10588 ** can return a result code other than SQLITE_OK or SQLITE_NOTFOUND if 10589 ** something goes wrong. 10590 ** 10591 ** The sqlite3_vtab_rhs_value() interface is usually only successful if 10592 ** the right-hand operand of a constraint is a literal value in the original 10593 ** SQL statement. If the right-hand operand is an expression or a reference 10594 ** to some other column or a [host parameter], then sqlite3_vtab_rhs_value() 10595 ** will probably return [SQLITE_NOTFOUND]. 10596 ** 10597 ** ^(Some constraints, such as [SQLITE_INDEX_CONSTRAINT_ISNULL] and 10598 ** [SQLITE_INDEX_CONSTRAINT_ISNOTNULL], have no right-hand operand. For such 10599 ** constraints, sqlite3_vtab_rhs_value() always returns SQLITE_NOTFOUND.)^ 10600 ** 10601 ** ^The [sqlite3_value] object returned in *V is a protected sqlite3_value 10602 ** and remains valid for the duration of the xBestIndex method call. 10603 ** ^When xBestIndex returns, the sqlite3_value object returned by 10604 ** sqlite3_vtab_rhs_value() is automatically deallocated. 10605 ** 10606 ** The "_rhs_" in the name of this routine is an abbreviation for 10607 ** "Right-Hand Side". 10608 */ 10609 SQLITE_API int sqlite3_vtab_rhs_value(sqlite3_index_info*, int, sqlite3_value **ppVal); 10610 10611 /* 10612 ** CAPI3REF: Conflict resolution modes 10613 ** KEYWORDS: {conflict resolution mode} 10614 ** 10615 ** These constants are returned by [sqlite3_vtab_on_conflict()] to 10616 ** inform a [virtual table] implementation of the [ON CONFLICT] mode 10617 ** for the SQL statement being evaluated. 10618 ** 10619 ** Note that the [SQLITE_IGNORE] constant is also used as a potential 10620 ** return value from the [sqlite3_set_authorizer()] callback and that 10621 ** [SQLITE_ABORT] is also a [result code]. 10622 */ 10623 #define SQLITE_ROLLBACK 1 10624 /* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */ 10625 #define SQLITE_FAIL 3 10626 /* #define SQLITE_ABORT 4 // Also an error code */ 10627 #define SQLITE_REPLACE 5 10628 10629 /* 10630 ** CAPI3REF: Prepared Statement Scan Status Opcodes 10631 ** KEYWORDS: {scanstatus options} 10632 ** 10633 ** The following constants can be used for the T parameter to the 10634 ** [sqlite3_stmt_scanstatus(S,X,T,V)] interface. Each constant designates a 10635 ** different metric for sqlite3_stmt_scanstatus() to return. 10636 ** 10637 ** When the value returned to V is a string, space to hold that string is 10638 ** managed by the prepared statement S and will be automatically freed when 10639 ** S is finalized. 10640 ** 10641 ** Not all values are available for all query elements. When a value is 10642 ** not available, the output variable is set to -1 if the value is numeric, 10643 ** or to NULL if it is a string (SQLITE_SCANSTAT_NAME). 10644 ** 10645 ** <dl> 10646 ** [[SQLITE_SCANSTAT_NLOOP]] <dt>SQLITE_SCANSTAT_NLOOP</dt> 10647 ** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be 10648 ** set to the total number of times that the X-th loop has run.</dd> 10649 ** 10650 ** [[SQLITE_SCANSTAT_NVISIT]] <dt>SQLITE_SCANSTAT_NVISIT</dt> 10651 ** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be set 10652 ** to the total number of rows examined by all iterations of the X-th loop.</dd> 10653 ** 10654 ** [[SQLITE_SCANSTAT_EST]] <dt>SQLITE_SCANSTAT_EST</dt> 10655 ** <dd>^The "double" variable pointed to by the V parameter will be set to the 10656 ** query planner's estimate for the average number of rows output from each 10657 ** iteration of the X-th loop. If the query planner's estimate was accurate, 10658 ** then this value will approximate the quotient NVISIT/NLOOP and the 10659 ** product of this value for all prior loops with the same SELECTID will 10660 ** be the NLOOP value for the current loop.</dd> 10661 ** 10662 ** [[SQLITE_SCANSTAT_NAME]] <dt>SQLITE_SCANSTAT_NAME</dt> 10663 ** <dd>^The "const char *" variable pointed to by the V parameter will be set 10664 ** to a zero-terminated UTF-8 string containing the name of the index or table 10665 ** used for the X-th loop.</dd> 10666 ** 10667 ** [[SQLITE_SCANSTAT_EXPLAIN]] <dt>SQLITE_SCANSTAT_EXPLAIN</dt> 10668 ** <dd>^The "const char *" variable pointed to by the V parameter will be set 10669 ** to a zero-terminated UTF-8 string containing the [EXPLAIN QUERY PLAN] 10670 ** description for the X-th loop.</dd> 10671 ** 10672 ** [[SQLITE_SCANSTAT_SELECTID]] <dt>SQLITE_SCANSTAT_SELECTID</dt> 10673 ** <dd>^The "int" variable pointed to by the V parameter will be set to the 10674 ** id for the X-th query plan element. The id value is unique within the 10675 ** statement. The select-id is the same value as is output in the first 10676 ** column of an [EXPLAIN QUERY PLAN] query.</dd> 10677 ** 10678 ** [[SQLITE_SCANSTAT_PARENTID]] <dt>SQLITE_SCANSTAT_PARENTID</dt> 10679 ** <dd>The "int" variable pointed to by the V parameter will be set to the 10680 ** id of the parent of the current query element, if applicable, or 10681 ** to zero if the query element has no parent. This is the same value as 10682 ** returned in the second column of an [EXPLAIN QUERY PLAN] query.</dd> 10683 ** 10684 ** [[SQLITE_SCANSTAT_NCYCLE]] <dt>SQLITE_SCANSTAT_NCYCLE</dt> 10685 ** <dd>The sqlite3_int64 output value is set to the number of cycles, 10686 ** according to the processor time-stamp counter, that elapsed while the 10687 ** query element was being processed. This value is not available for 10688 ** all query elements - if it is unavailable the output variable is 10689 ** set to -1.</dd> 10690 ** </dl> 10691 */ 10692 #define SQLITE_SCANSTAT_NLOOP 0 10693 #define SQLITE_SCANSTAT_NVISIT 1 10694 #define SQLITE_SCANSTAT_EST 2 10695 #define SQLITE_SCANSTAT_NAME 3 10696 #define SQLITE_SCANSTAT_EXPLAIN 4 10697 #define SQLITE_SCANSTAT_SELECTID 5 10698 #define SQLITE_SCANSTAT_PARENTID 6 10699 #define SQLITE_SCANSTAT_NCYCLE 7 10700 10701 /* 10702 ** CAPI3REF: Prepared Statement Scan Status 10703 ** METHOD: sqlite3_stmt 10704 ** 10705 ** These interfaces return information about the predicted and measured 10706 ** performance for pStmt. Advanced applications can use this 10707 ** interface to compare the predicted and the measured performance and 10708 ** issue warnings and/or rerun [ANALYZE] if discrepancies are found. 10709 ** 10710 ** Since this interface is expected to be rarely used, it is only 10711 ** available if SQLite is compiled using the [SQLITE_ENABLE_STMT_SCANSTATUS] 10712 ** compile-time option. 10713 ** 10714 ** The "iScanStatusOp" parameter determines which status information to return. 10715 ** The "iScanStatusOp" must be one of the [scanstatus options] or the behavior 10716 ** of this interface is undefined. ^The requested measurement is written into 10717 ** a variable pointed to by the "pOut" parameter. 10718 ** 10719 ** The "flags" parameter must be passed a mask of flags. At present only 10720 ** one flag is defined - [SQLITE_SCANSTAT_COMPLEX]. If SQLITE_SCANSTAT_COMPLEX 10721 ** is specified, then status information is available for all elements 10722 ** of a query plan that are reported by "[EXPLAIN QUERY PLAN]" output. If 10723 ** SQLITE_SCANSTAT_COMPLEX is not specified, then only query plan elements 10724 ** that correspond to query loops (the "SCAN..." and "SEARCH..." elements of 10725 ** the EXPLAIN QUERY PLAN output) are available. Invoking API 10726 ** sqlite3_stmt_scanstatus() is equivalent to calling 10727 ** sqlite3_stmt_scanstatus_v2() with a zeroed flags parameter. 10728 ** 10729 ** Parameter "idx" identifies the specific query element to retrieve statistics 10730 ** for. Query elements are numbered starting from zero. A value of -1 may 10731 ** retrieve statistics for the entire query. ^If idx is out of range 10732 ** - less than -1 or greater than or equal to the total number of query 10733 ** elements used to implement the statement - a non-zero value is returned and 10734 ** the variable that pOut points to is unchanged. 10735 ** 10736 ** See also: [sqlite3_stmt_scanstatus_reset()] and the 10737 ** [nexec and ncycle] columns of the [bytecode virtual table]. 10738 */ 10739 SQLITE_API int sqlite3_stmt_scanstatus( 10740 sqlite3_stmt *pStmt, /* Prepared statement for which info desired */ 10741 int idx, /* Index of loop to report on */ 10742 int iScanStatusOp, /* Information desired. SQLITE_SCANSTAT_* */ 10743 void *pOut /* Result written here */ 10744 ); 10745 SQLITE_API int sqlite3_stmt_scanstatus_v2( 10746 sqlite3_stmt *pStmt, /* Prepared statement for which info desired */ 10747 int idx, /* Index of loop to report on */ 10748 int iScanStatusOp, /* Information desired. SQLITE_SCANSTAT_* */ 10749 int flags, /* Mask of flags defined below */ 10750 void *pOut /* Result written here */ 10751 ); 10752 10753 /* 10754 ** CAPI3REF: Prepared Statement Scan Status 10755 ** KEYWORDS: {scan status flags} 10756 */ 10757 #define SQLITE_SCANSTAT_COMPLEX 0x0001 10758 10759 /* 10760 ** CAPI3REF: Zero Scan-Status Counters 10761 ** METHOD: sqlite3_stmt 10762 ** 10763 ** ^Zero all [sqlite3_stmt_scanstatus()] related event counters. 10764 ** 10765 ** This API is only available if the library is built with pre-processor 10766 ** symbol [SQLITE_ENABLE_STMT_SCANSTATUS] defined. 10767 */ 10768 SQLITE_API void sqlite3_stmt_scanstatus_reset(sqlite3_stmt*); 10769 10770 /* 10771 ** CAPI3REF: Flush caches to disk mid-transaction 10772 ** METHOD: sqlite3 10773 ** 10774 ** ^If a write-transaction is open on [database connection] D when the 10775 ** [sqlite3_db_cacheflush(D)] interface is invoked, any dirty 10776 ** pages in the pager-cache that are not currently in use are written out 10777 ** to disk. A dirty page may be in use if a database cursor created by an 10778 ** active SQL statement is reading from it, or if it is page 1 of a database 10779 ** file (page 1 is always "in use"). ^The [sqlite3_db_cacheflush(D)] 10780 ** interface flushes caches for all schemas - "main", "temp", and 10781 ** any [attached] databases. 10782 ** 10783 ** ^If this function needs to obtain extra database locks before dirty pages 10784 ** can be flushed to disk, it does so. ^If those locks cannot be obtained 10785 ** immediately and there is a busy-handler callback configured, it is invoked 10786 ** in the usual manner. ^If the required lock still cannot be obtained, then 10787 ** the database is skipped and an attempt made to flush any dirty pages 10788 ** belonging to the next (if any) database. ^If any databases are skipped 10789 ** because locks cannot be obtained, but no other error occurs, this 10790 ** function returns SQLITE_BUSY. 10791 ** 10792 ** ^If any other error occurs while flushing dirty pages to disk (for 10793 ** example an IO error or out-of-memory condition), then processing is 10794 ** abandoned and an SQLite [error code] is returned to the caller immediately. 10795 ** 10796 ** ^Otherwise, if no error occurs, [sqlite3_db_cacheflush()] returns SQLITE_OK. 10797 ** 10798 ** ^This function does not set the database handle error code or message 10799 ** returned by the [sqlite3_errcode()] and [sqlite3_errmsg()] functions. 10800 */ 10801 SQLITE_API int sqlite3_db_cacheflush(sqlite3*); 10802 10803 /* 10804 ** CAPI3REF: The pre-update hook. 10805 ** METHOD: sqlite3 10806 ** 10807 ** ^These interfaces are only available if SQLite is compiled using the 10808 ** [SQLITE_ENABLE_PREUPDATE_HOOK] compile-time option. 10809 ** 10810 ** ^The [sqlite3_preupdate_hook()] interface registers a callback function 10811 ** that is invoked prior to each [INSERT], [UPDATE], and [DELETE] operation 10812 ** on a database table. 10813 ** ^At most one preupdate hook may be registered at a time on a single 10814 ** [database connection]; each call to [sqlite3_preupdate_hook()] overrides 10815 ** the previous setting. 10816 ** ^The preupdate hook is disabled by invoking [sqlite3_preupdate_hook()] 10817 ** with a NULL pointer as the second parameter. 10818 ** ^The third parameter to [sqlite3_preupdate_hook()] is passed through as 10819 ** the first parameter to callbacks. 10820 ** 10821 ** ^The preupdate hook only fires for changes to real database tables; the 10822 ** preupdate hook is not invoked for changes to [virtual tables] or to 10823 ** system tables like sqlite_sequence or sqlite_stat1. 10824 ** 10825 ** ^The second parameter to the preupdate callback is a pointer to 10826 ** the [database connection] that registered the preupdate hook. 10827 ** ^The third parameter to the preupdate callback is one of the constants 10828 ** [SQLITE_INSERT], [SQLITE_DELETE], or [SQLITE_UPDATE] to identify the 10829 ** kind of update operation that is about to occur. 10830 ** ^(The fourth parameter to the preupdate callback is the name of the 10831 ** database within the database connection that is being modified. This 10832 ** will be "main" for the main database or "temp" for TEMP tables or 10833 ** the name given after the AS keyword in the [ATTACH] statement for attached 10834 ** databases.)^ 10835 ** ^The fifth parameter to the preupdate callback is the name of the 10836 ** table that is being modified. 10837 ** 10838 ** For an UPDATE or DELETE operation on a [rowid table], the sixth 10839 ** parameter passed to the preupdate callback is the initial [rowid] of the 10840 ** row being modified or deleted. For an INSERT operation on a rowid table, 10841 ** or any operation on a WITHOUT ROWID table, the value of the sixth 10842 ** parameter is undefined. For an INSERT or UPDATE on a rowid table the 10843 ** seventh parameter is the final rowid value of the row being inserted 10844 ** or updated. The value of the seventh parameter passed to the callback 10845 ** function is not defined for operations on WITHOUT ROWID tables, or for 10846 ** DELETE operations on rowid tables. 10847 ** 10848 ** ^The sqlite3_preupdate_hook(D,C,P) function returns the P argument from 10849 ** the previous call on the same [database connection] D, or NULL for 10850 ** the first call on D. 10851 ** 10852 ** The [sqlite3_preupdate_old()], [sqlite3_preupdate_new()], 10853 ** [sqlite3_preupdate_count()], and [sqlite3_preupdate_depth()] interfaces 10854 ** provide additional information about a preupdate event. These routines 10855 ** may only be called from within a preupdate callback. Invoking any of 10856 ** these routines from outside of a preupdate callback or with a 10857 ** [database connection] pointer that is different from the one supplied 10858 ** to the preupdate callback results in undefined and probably undesirable 10859 ** behavior. 10860 ** 10861 ** ^The [sqlite3_preupdate_count(D)] interface returns the number of columns 10862 ** in the row that is being inserted, updated, or deleted. 10863 ** 10864 ** ^The [sqlite3_preupdate_old(D,N,P)] interface writes into P a pointer to 10865 ** a [protected sqlite3_value] that contains the value of the Nth column of 10866 ** the table row before it is updated. The N parameter must be between 0 10867 ** and one less than the number of columns or the behavior will be 10868 ** undefined. This must only be used within SQLITE_UPDATE and SQLITE_DELETE 10869 ** preupdate callbacks; if it is used by an SQLITE_INSERT callback then the 10870 ** behavior is undefined. The [sqlite3_value] that P points to 10871 ** will be destroyed when the preupdate callback returns. 10872 ** 10873 ** ^The [sqlite3_preupdate_new(D,N,P)] interface writes into P a pointer to 10874 ** a [protected sqlite3_value] that contains the value of the Nth column of 10875 ** the table row after it is updated. The N parameter must be between 0 10876 ** and one less than the number of columns or the behavior will be 10877 ** undefined. This must only be used within SQLITE_INSERT and SQLITE_UPDATE 10878 ** preupdate callbacks; if it is used by an SQLITE_DELETE callback then the 10879 ** behavior is undefined. The [sqlite3_value] that P points to 10880 ** will be destroyed when the preupdate callback returns. 10881 ** 10882 ** ^The [sqlite3_preupdate_depth(D)] interface returns 0 if the preupdate 10883 ** callback was invoked as a result of a direct insert, update, or delete 10884 ** operation; or 1 for inserts, updates, or deletes invoked by top-level 10885 ** triggers; or 2 for changes resulting from triggers called by top-level 10886 ** triggers; and so forth. 10887 ** 10888 ** When the [sqlite3_blob_write()] API is used to update a blob column, 10889 ** the pre-update hook is invoked with SQLITE_DELETE, because 10890 ** the new values are not yet available. In this case, when a 10891 ** callback made with op==SQLITE_DELETE is actually a write using the 10892 ** sqlite3_blob_write() API, the [sqlite3_preupdate_blobwrite()] returns 10893 ** the index of the column being written. In other cases, where the 10894 ** pre-update hook is being invoked for some other reason, including a 10895 ** regular DELETE, sqlite3_preupdate_blobwrite() returns -1. 10896 ** 10897 ** See also: [sqlite3_update_hook()] 10898 */ 10899 #if defined(SQLITE_ENABLE_PREUPDATE_HOOK) 10900 SQLITE_API void *sqlite3_preupdate_hook( 10901 sqlite3 *db, 10902 void(*xPreUpdate)( 10903 void *pCtx, /* Copy of third arg to preupdate_hook() */ 10904 sqlite3 *db, /* Database handle */ 10905 int op, /* SQLITE_UPDATE, DELETE or INSERT */ 10906 char const *zDb, /* Database name */ 10907 char const *zName, /* Table name */ 10908 sqlite3_int64 iKey1, /* Rowid of row about to be deleted/updated */ 10909 sqlite3_int64 iKey2 /* New rowid value (for a rowid UPDATE) */ 10910 ), 10911 void* 10912 ); 10913 SQLITE_API int sqlite3_preupdate_old(sqlite3 *, int, sqlite3_value **); 10914 SQLITE_API int sqlite3_preupdate_count(sqlite3 *); 10915 SQLITE_API int sqlite3_preupdate_depth(sqlite3 *); 10916 SQLITE_API int sqlite3_preupdate_new(sqlite3 *, int, sqlite3_value **); 10917 SQLITE_API int sqlite3_preupdate_blobwrite(sqlite3 *); 10918 #endif 10919 10920 /* 10921 ** CAPI3REF: Low-level system error code 10922 ** METHOD: sqlite3 10923 ** 10924 ** ^Attempt to return the underlying operating system error code or error 10925 ** number that caused the most recent I/O error or failure to open a file. 10926 ** The return value is OS-dependent. For example, on unix systems, after 10927 ** [sqlite3_open_v2()] returns [SQLITE_CANTOPEN], this interface could be 10928 ** called to get back the underlying "errno" that caused the problem, such 10929 ** as ENOSPC, EAUTH, EISDIR, and so forth. 10930 */ 10931 SQLITE_API int sqlite3_system_errno(sqlite3*); 10932 10933 /* 10934 ** CAPI3REF: Database Snapshot 10935 ** KEYWORDS: {snapshot} {sqlite3_snapshot} 10936 ** 10937 ** An instance of the snapshot object records the state of a [WAL mode] 10938 ** database for some specific point in history. 10939 ** 10940 ** In [WAL mode], multiple [database connections] that are open on the 10941 ** same database file can each be reading a different historical version 10942 ** of the database file. When a [database connection] begins a read 10943 ** transaction, that connection sees an unchanging copy of the database 10944 ** as it existed for the point in time when the transaction first started. 10945 ** Subsequent changes to the database from other connections are not seen 10946 ** by the reader until a new read transaction is started. 10947 ** 10948 ** The sqlite3_snapshot object records state information about an historical 10949 ** version of the database file so that it is possible to later open a new read 10950 ** transaction that sees that historical version of the database rather than 10951 ** the most recent version. 10952 */ 10953 typedef struct sqlite3_snapshot { 10954 unsigned char hidden[48]; 10955 } sqlite3_snapshot; 10956 10957 /* 10958 ** CAPI3REF: Record A Database Snapshot 10959 ** CONSTRUCTOR: sqlite3_snapshot 10960 ** 10961 ** ^The [sqlite3_snapshot_get(D,S,P)] interface attempts to make a 10962 ** new [sqlite3_snapshot] object that records the current state of 10963 ** schema S in database connection D. ^On success, the 10964 ** [sqlite3_snapshot_get(D,S,P)] interface writes a pointer to the newly 10965 ** created [sqlite3_snapshot] object into *P and returns SQLITE_OK. 10966 ** If there is not already a read-transaction open on schema S when 10967 ** this function is called, one is opened automatically. 10968 ** 10969 ** If a read-transaction is opened by this function, then it is guaranteed 10970 ** that the returned snapshot object may not be invalidated by a database 10971 ** writer or checkpointer until after the read-transaction is closed. This 10972 ** is not guaranteed if a read-transaction is already open when this 10973 ** function is called. In that case, any subsequent write or checkpoint 10974 ** operation on the database may invalidate the returned snapshot handle, 10975 ** even while the read-transaction remains open. 10976 ** 10977 ** The following must be true for this function to succeed. If any of 10978 ** the following statements are false when sqlite3_snapshot_get() is 10979 ** called, SQLITE_ERROR is returned. The final value of *P is undefined 10980 ** in this case. 10981 ** 10982 ** <ul> 10983 ** <li> The database handle must not be in [autocommit mode]. 10984 ** 10985 ** <li> Schema S of [database connection] D must be a [WAL mode] database. 10986 ** 10987 ** <li> There must not be a write transaction open on schema S of database 10988 ** connection D. 10989 ** 10990 ** <li> One or more transactions must have been written to the current wal 10991 ** file since it was created on disk (by any connection). This means 10992 ** that a snapshot cannot be taken on a wal mode database with no wal 10993 ** file immediately after it is first opened. At least one transaction 10994 ** must be written to it first. 10995 ** </ul> 10996 ** 10997 ** This function may also return SQLITE_NOMEM. If it is called with the 10998 ** database handle in autocommit mode but fails for some other reason, 10999 ** whether or not a read transaction is opened on schema S is undefined. 11000 ** 11001 ** The [sqlite3_snapshot] object returned from a successful call to 11002 ** [sqlite3_snapshot_get()] must be freed using [sqlite3_snapshot_free()] 11003 ** to avoid a memory leak. 11004 ** 11005 ** The [sqlite3_snapshot_get()] interface is only available when the 11006 ** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. 11007 */ 11008 SQLITE_API int sqlite3_snapshot_get( 11009 sqlite3 *db, 11010 const char *zSchema, 11011 sqlite3_snapshot **ppSnapshot 11012 ); 11013 11014 /* 11015 ** CAPI3REF: Start a read transaction on an historical snapshot 11016 ** METHOD: sqlite3_snapshot 11017 ** 11018 ** ^The [sqlite3_snapshot_open(D,S,P)] interface either starts a new read 11019 ** transaction or upgrades an existing one for schema S of 11020 ** [database connection] D such that the read transaction refers to 11021 ** historical [snapshot] P, rather than the most recent change to the 11022 ** database. ^The [sqlite3_snapshot_open()] interface returns SQLITE_OK 11023 ** on success or an appropriate [error code] if it fails. 11024 ** 11025 ** ^In order to succeed, the database connection must not be in 11026 ** [autocommit mode] when [sqlite3_snapshot_open(D,S,P)] is called. If there 11027 ** is already a read transaction open on schema S, then the database handle 11028 ** must have no active statements (SELECT statements that have been passed 11029 ** to sqlite3_step() but not sqlite3_reset() or sqlite3_finalize()). 11030 ** SQLITE_ERROR is returned if either of these conditions is violated, or 11031 ** if schema S does not exist, or if the snapshot object is invalid. 11032 ** 11033 ** ^A call to sqlite3_snapshot_open() will fail to open if the specified 11034 ** snapshot has been overwritten by a [checkpoint]. In this case 11035 ** SQLITE_ERROR_SNAPSHOT is returned. 11036 ** 11037 ** If there is already a read transaction open when this function is 11038 ** invoked, then the same read transaction remains open (on the same 11039 ** database snapshot) if SQLITE_ERROR, SQLITE_BUSY or SQLITE_ERROR_SNAPSHOT 11040 ** is returned. If another error code - for example SQLITE_PROTOCOL or an 11041 ** SQLITE_IOERR error code - is returned, then the final state of the 11042 ** read transaction is undefined. If SQLITE_OK is returned, then the 11043 ** read transaction is now open on database snapshot P. 11044 ** 11045 ** ^(A call to [sqlite3_snapshot_open(D,S,P)] will fail if the 11046 ** database connection D does not know that the database file for 11047 ** schema S is in [WAL mode]. A database connection might not know 11048 ** that the database file is in [WAL mode] if there has been no prior 11049 ** I/O on that database connection, or if the database entered [WAL mode] 11050 ** after the most recent I/O on the database connection.)^ 11051 ** (Hint: Run "[PRAGMA application_id]" against a newly opened 11052 ** database connection in order to make it ready to use snapshots.) 11053 ** 11054 ** The [sqlite3_snapshot_open()] interface is only available when the 11055 ** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. 11056 */ 11057 SQLITE_API int sqlite3_snapshot_open( 11058 sqlite3 *db, 11059 const char *zSchema, 11060 sqlite3_snapshot *pSnapshot 11061 ); 11062 11063 /* 11064 ** CAPI3REF: Destroy a snapshot 11065 ** DESTRUCTOR: sqlite3_snapshot 11066 ** 11067 ** ^The [sqlite3_snapshot_free(P)] interface destroys [sqlite3_snapshot] P. 11068 ** The application must eventually free every [sqlite3_snapshot] object 11069 ** using this routine to avoid a memory leak. 11070 ** 11071 ** The [sqlite3_snapshot_free()] interface is only available when the 11072 ** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. 11073 */ 11074 SQLITE_API void sqlite3_snapshot_free(sqlite3_snapshot*); 11075 11076 /* 11077 ** CAPI3REF: Compare the ages of two snapshot handles. 11078 ** METHOD: sqlite3_snapshot 11079 ** 11080 ** The sqlite3_snapshot_cmp(P1, P2) interface is used to compare the ages 11081 ** of two valid snapshot handles. 11082 ** 11083 ** If the two snapshot handles are not associated with the same database 11084 ** file, the result of the comparison is undefined. 11085 ** 11086 ** Additionally, the result of the comparison is only valid if both of the 11087 ** snapshot handles were obtained by calling sqlite3_snapshot_get() since the 11088 ** last time the wal file was deleted. The wal file is deleted when the 11089 ** database is changed back to rollback mode or when the number of database 11090 ** clients drops to zero. If either snapshot handle was obtained before the 11091 ** wal file was last deleted, the value returned by this function 11092 ** is undefined. 11093 ** 11094 ** Otherwise, this API returns a negative value if P1 refers to an older 11095 ** snapshot than P2, zero if the two handles refer to the same database 11096 ** snapshot, and a positive value if P1 is a newer snapshot than P2. 11097 ** 11098 ** This interface is only available if SQLite is compiled with the 11099 ** [SQLITE_ENABLE_SNAPSHOT] option. 11100 */ 11101 SQLITE_API int sqlite3_snapshot_cmp( 11102 sqlite3_snapshot *p1, 11103 sqlite3_snapshot *p2 11104 ); 11105 11106 /* 11107 ** CAPI3REF: Recover snapshots from a wal file 11108 ** METHOD: sqlite3_snapshot 11109 ** 11110 ** If a [WAL file] remains on disk after all database connections close 11111 ** (either through the use of the [SQLITE_FCNTL_PERSIST_WAL] [file control] 11112 ** or because the last process to have the database opened exited without 11113 ** calling [sqlite3_close()]) and a new connection is subsequently opened 11114 ** on that database and [WAL file], the [sqlite3_snapshot_open()] interface 11115 ** will only be able to open the last transaction added to the WAL file 11116 ** even though the WAL file contains other valid transactions. 11117 ** 11118 ** This function attempts to scan the WAL file associated with database zDb 11119 ** of database handle db and make all valid snapshots available to 11120 ** sqlite3_snapshot_open(). It is an error if there is already a read 11121 ** transaction open on the database, or if the database is not a WAL mode 11122 ** database. 11123 ** 11124 ** SQLITE_OK is returned if successful, or an SQLite error code otherwise. 11125 ** 11126 ** This interface is only available if SQLite is compiled with the 11127 ** [SQLITE_ENABLE_SNAPSHOT] option. 11128 */ 11129 SQLITE_API int sqlite3_snapshot_recover(sqlite3 *db, const char *zDb); 11130 11131 /* 11132 ** CAPI3REF: Serialize a database 11133 ** 11134 ** The sqlite3_serialize(D,S,P,F) interface returns a pointer to 11135 ** memory that is a serialization of the S database on 11136 ** [database connection] D. If S is a NULL pointer, the main database is used. 11137 ** If P is not a NULL pointer, then the size of the database in bytes 11138 ** is written into *P. 11139 ** 11140 ** For an ordinary on-disk database file, the serialization is just a 11141 ** copy of the disk file. For an in-memory database or a "TEMP" database, 11142 ** the serialization is the same sequence of bytes which would be written 11143 ** to disk if that database were backed up to disk. 11144 ** 11145 ** The usual case is that sqlite3_serialize() copies the serialization of 11146 ** the database into memory obtained from [sqlite3_malloc64()] and returns 11147 ** a pointer to that memory. The caller is responsible for freeing the 11148 ** returned value to avoid a memory leak. However, if the F argument 11149 ** contains the SQLITE_SERIALIZE_NOCOPY bit, then no memory allocations 11150 ** are made, and the sqlite3_serialize() function will return a pointer 11151 ** to the contiguous memory representation of the database that SQLite 11152 ** is currently using for that database, or NULL if no such contiguous 11153 ** memory representation of the database exists. A contiguous memory 11154 ** representation of the database will usually only exist if there has 11155 ** been a prior call to [sqlite3_deserialize(D,S,...)] with the same 11156 ** values of D and S. 11157 ** The size of the database is written into *P even if the 11158 ** SQLITE_SERIALIZE_NOCOPY bit is set but no contiguous copy 11159 ** of the database exists. 11160 ** 11161 ** After the call, if the SQLITE_SERIALIZE_NOCOPY bit had been set, 11162 ** the returned buffer content will remain accessible and unchanged 11163 ** until either the next write operation on the connection or when 11164 ** the connection is closed, and applications must not modify the 11165 ** buffer. If the bit had been clear, the returned buffer will not 11166 ** be accessed by SQLite after the call. 11167 ** 11168 ** A call to sqlite3_serialize(D,S,P,F) might return NULL even if the 11169 ** SQLITE_SERIALIZE_NOCOPY bit is omitted from argument F if a memory 11170 ** allocation error occurs. 11171 ** 11172 ** This interface is omitted if SQLite is compiled with the 11173 ** [SQLITE_OMIT_DESERIALIZE] option. 11174 */ 11175 SQLITE_API unsigned char *sqlite3_serialize( 11176 sqlite3 *db, /* The database connection */ 11177 const char *zSchema, /* Which DB to serialize. ex: "main", "temp", ... */ 11178 sqlite3_int64 *piSize, /* Write size of the DB here, if not NULL */ 11179 unsigned int mFlags /* Zero or more SQLITE_SERIALIZE_* flags */ 11180 ); 11181 11182 /* 11183 ** CAPI3REF: Flags for sqlite3_serialize 11184 ** 11185 ** Zero or more of the following constants can be OR-ed together for 11186 ** the F argument to [sqlite3_serialize(D,S,P,F)]. 11187 ** 11188 ** SQLITE_SERIALIZE_NOCOPY means that [sqlite3_serialize()] will return 11189 ** a pointer to contiguous in-memory database that it is currently using, 11190 ** without making a copy of the database. If SQLite is not currently using 11191 ** a contiguous in-memory database, then this option causes 11192 ** [sqlite3_serialize()] to return a NULL pointer. SQLite will only be 11193 ** using a contiguous in-memory database if it has been initialized by a 11194 ** prior call to [sqlite3_deserialize()]. 11195 */ 11196 #define SQLITE_SERIALIZE_NOCOPY 0x001 /* Do no memory allocations */ 11197 11198 /* 11199 ** CAPI3REF: Deserialize a database 11200 ** 11201 ** The sqlite3_deserialize(D,S,P,N,M,F) interface causes the 11202 ** [database connection] D to disconnect from database S and then 11203 ** reopen S as an in-memory database based on the serialization 11204 ** contained in P. If S is a NULL pointer, the main database is 11205 ** used. The serialized database P is N bytes in size. M is the size 11206 ** of the buffer P, which might be larger than N. If M is larger than 11207 ** N, and the SQLITE_DESERIALIZE_READONLY bit is not set in F, then 11208 ** SQLite is permitted to add content to the in-memory database as 11209 ** long as the total size does not exceed M bytes. 11210 ** 11211 ** If the SQLITE_DESERIALIZE_FREEONCLOSE bit is set in F, then SQLite will 11212 ** invoke sqlite3_free() on the serialization buffer when the database 11213 ** connection closes. If the SQLITE_DESERIALIZE_RESIZEABLE bit is set, then 11214 ** SQLite will try to increase the buffer size using sqlite3_realloc64() 11215 ** if writes on the database cause it to grow larger than M bytes. 11216 ** 11217 ** Applications must not modify the buffer P or invalidate it before 11218 ** the database connection D is closed. 11219 ** 11220 ** The sqlite3_deserialize() interface will fail with SQLITE_BUSY if the 11221 ** database is currently in a read transaction or is involved in a backup 11222 ** operation. 11223 ** 11224 ** It is not possible to deserialize into the TEMP database. If the 11225 ** S argument to sqlite3_deserialize(D,S,P,N,M,F) is "temp" then the 11226 ** function returns SQLITE_ERROR. 11227 ** 11228 ** The deserialized database should not be in [WAL mode]. If the database 11229 ** is in WAL mode, then any attempt to use the database file will result 11230 ** in an [SQLITE_CANTOPEN] error. The application can set the 11231 ** [file format version numbers] (bytes 18 and 19) of the input database P 11232 ** to 0x01 prior to invoking sqlite3_deserialize(D,S,P,N,M,F) to force the 11233 ** database file into rollback mode and work around this limitation. 11234 ** 11235 ** If sqlite3_deserialize(D,S,P,N,M,F) fails for any reason and if the 11236 ** SQLITE_DESERIALIZE_FREEONCLOSE bit is set in argument F, then 11237 ** [sqlite3_free()] is invoked on argument P prior to returning. 11238 ** 11239 ** This interface is omitted if SQLite is compiled with the 11240 ** [SQLITE_OMIT_DESERIALIZE] option. 11241 */ 11242 SQLITE_API int sqlite3_deserialize( 11243 sqlite3 *db, /* The database connection */ 11244 const char *zSchema, /* Which DB to reopen with the deserialization */ 11245 unsigned char *pData, /* The serialized database content */ 11246 sqlite3_int64 szDb, /* Number of bytes in the deserialization */ 11247 sqlite3_int64 szBuf, /* Total size of buffer pData[] */ 11248 unsigned mFlags /* Zero or more SQLITE_DESERIALIZE_* flags */ 11249 ); 11250 11251 /* 11252 ** CAPI3REF: Flags for sqlite3_deserialize() 11253 ** 11254 ** The following are allowed values for the 6th argument (the F argument) to 11255 ** the [sqlite3_deserialize(D,S,P,N,M,F)] interface. 11256 ** 11257 ** The SQLITE_DESERIALIZE_FREEONCLOSE means that the database serialization 11258 ** in the P argument is held in memory obtained from [sqlite3_malloc64()] 11259 ** and that SQLite should take ownership of this memory and automatically 11260 ** free it when it has finished using it. Without this flag, the caller 11261 ** is responsible for freeing any dynamically allocated memory. 11262 ** 11263 ** The SQLITE_DESERIALIZE_RESIZEABLE flag means that SQLite is allowed to 11264 ** grow the size of the database using calls to [sqlite3_realloc64()]. This 11265 ** flag should only be used if SQLITE_DESERIALIZE_FREEONCLOSE is also used. 11266 ** Without this flag, the deserialized database cannot increase in size beyond 11267 ** the number of bytes specified by the M parameter. 11268 ** 11269 ** The SQLITE_DESERIALIZE_READONLY flag means that the deserialized database 11270 ** should be treated as read-only. 11271 */ 11272 #define SQLITE_DESERIALIZE_FREEONCLOSE 1 /* Call sqlite3_free() on close */ 11273 #define SQLITE_DESERIALIZE_RESIZEABLE 2 /* Resize using sqlite3_realloc64() */ 11274 #define SQLITE_DESERIALIZE_READONLY 4 /* Database is read-only */ 11275 11276 /* 11277 ** CAPI3REF: Bind array values to the CARRAY table-valued function 11278 ** 11279 ** The sqlite3_carray_bind_v2(S,I,P,N,F,X,D) interface binds an array value to 11280 ** parameter that is the first argument of the [carray() table-valued function]. 11281 ** The S parameter is a pointer to the [prepared statement] that uses the 11282 ** carray() functions. I is the parameter index to be bound. I must be the 11283 ** index of the parameter that is the first argument to the carray() 11284 ** table-valued function. P is a pointer to the array to be bound, and N 11285 ** is the number of elements in the array. The F argument is one of 11286 ** constants [SQLITE_CARRAY_INT32], [SQLITE_CARRAY_INT64], 11287 ** [SQLITE_CARRAY_DOUBLE], [SQLITE_CARRAY_TEXT], 11288 ** or [SQLITE_CARRAY_BLOB] to indicate the datatype of the array P. 11289 ** 11290 ** If the X argument is not a NULL pointer or one of the special 11291 ** values [SQLITE_STATIC] or [SQLITE_TRANSIENT], then SQLite will invoke 11292 ** the function X with argument D when it is finished using the data in P. 11293 ** The call to X(D) is a destructor for the array P. The destructor X(D) 11294 ** is invoked even if the call to sqlite3_carray_bind_v2() fails. If the X 11295 ** parameter is the special-case value [SQLITE_STATIC], then SQLite assumes 11296 ** that the data static and the destructor is never invoked. If the X 11297 ** parameter is the special-case value [SQLITE_TRANSIENT], then 11298 ** sqlite3_carray_bind_v2() makes its own private copy of the data prior 11299 ** to returning and never invokes the destructor X. 11300 ** 11301 ** The sqlite3_carray_bind() function works the same as sqlite3_carray_bind_v2() 11302 ** with a D parameter set to P. In other words, 11303 ** sqlite3_carray_bind(S,I,P,N,F,X) is same as 11304 ** sqlite3_carray_bind_v2(S,I,P,N,F,X,P). 11305 */ 11306 SQLITE_API int sqlite3_carray_bind_v2( 11307 sqlite3_stmt *pStmt, /* Statement to be bound */ 11308 int i, /* Parameter index */ 11309 void *aData, /* Pointer to array data */ 11310 int nData, /* Number of data elements */ 11311 int mFlags, /* CARRAY flags */ 11312 void (*xDel)(void*), /* Destructor for aData */ 11313 void *pDel /* Optional argument to xDel() */ 11314 ); 11315 SQLITE_API int sqlite3_carray_bind( 11316 sqlite3_stmt *pStmt, /* Statement to be bound */ 11317 int i, /* Parameter index */ 11318 void *aData, /* Pointer to array data */ 11319 int nData, /* Number of data elements */ 11320 int mFlags, /* CARRAY flags */ 11321 void (*xDel)(void*) /* Destructor for aData */ 11322 ); 11323 11324 /* 11325 ** CAPI3REF: Datatypes for the CARRAY table-valued function 11326 ** 11327 ** The fifth argument to the [sqlite3_carray_bind()] interface musts be 11328 ** one of the following constants, to specify the datatype of the array 11329 ** that is being bound into the [carray table-valued function]. 11330 */ 11331 #define SQLITE_CARRAY_INT32 0 /* Data is 32-bit signed integers */ 11332 #define SQLITE_CARRAY_INT64 1 /* Data is 64-bit signed integers */ 11333 #define SQLITE_CARRAY_DOUBLE 2 /* Data is doubles */ 11334 #define SQLITE_CARRAY_TEXT 3 /* Data is char* */ 11335 #define SQLITE_CARRAY_BLOB 4 /* Data is struct iovec */ 11336 11337 /* 11338 ** Versions of the above #defines that omit the initial SQLITE_, for 11339 ** legacy compatibility. 11340 */ 11341 #define CARRAY_INT32 0 /* Data is 32-bit signed integers */ 11342 #define CARRAY_INT64 1 /* Data is 64-bit signed integers */ 11343 #define CARRAY_DOUBLE 2 /* Data is doubles */ 11344 #define CARRAY_TEXT 3 /* Data is char* */ 11345 #define CARRAY_BLOB 4 /* Data is struct iovec */ 11346 11347 /* 11348 ** Undo the hack that converts floating point types to integer for 11349 ** builds on processors without floating point support. 11350 */ 11351 #ifdef SQLITE_OMIT_FLOATING_POINT 11352 # undef double 11353 #endif 11354 11355 #if defined(__wasi__) 11356 # undef SQLITE_WASI 11357 # define SQLITE_WASI 1 11358 # ifndef SQLITE_OMIT_LOAD_EXTENSION 11359 # define SQLITE_OMIT_LOAD_EXTENSION 11360 # endif 11361 # ifndef SQLITE_THREADSAFE 11362 # define SQLITE_THREADSAFE 0 11363 # endif 11364 #endif 11365 11366 #ifdef __cplusplus 11367 } /* End of the 'extern "C"' block */ 11368 #endif 11369 /* #endif for SQLITE3_H will be added by mksqlite3.tcl */ 11370 11371 /******** Begin file sqlite3rtree.h *********/ 11372 /* 11373 ** 2010 August 30 11374 ** 11375 ** The author disclaims copyright to this source code. In place of 11376 ** a legal notice, here is a blessing: 11377 ** 11378 ** May you do good and not evil. 11379 ** May you find forgiveness for yourself and forgive others. 11380 ** May you share freely, never taking more than you give. 11381 ** 11382 ************************************************************************* 11383 */ 11384 11385 #ifndef _SQLITE3RTREE_H_ 11386 #define _SQLITE3RTREE_H_ 11387 11388 11389 #ifdef __cplusplus 11390 extern "C" { 11391 #endif 11392 11393 typedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry; 11394 typedef struct sqlite3_rtree_query_info sqlite3_rtree_query_info; 11395 11396 /* The double-precision datatype used by RTree depends on the 11397 ** SQLITE_RTREE_INT_ONLY compile-time option. 11398 */ 11399 #ifdef SQLITE_RTREE_INT_ONLY 11400 typedef sqlite3_int64 sqlite3_rtree_dbl; 11401 #else 11402 typedef double sqlite3_rtree_dbl; 11403 #endif 11404 11405 /* 11406 ** Register a geometry callback named zGeom that can be used as part of an 11407 ** R-Tree geometry query as follows: 11408 ** 11409 ** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zGeom(... params ...) 11410 */ 11411 SQLITE_API int sqlite3_rtree_geometry_callback( 11412 sqlite3 *db, 11413 const char *zGeom, 11414 int (*xGeom)(sqlite3_rtree_geometry*, int, sqlite3_rtree_dbl*,int*), 11415 void *pContext 11416 ); 11417 11418 11419 /* 11420 ** A pointer to a structure of the following type is passed as the first 11421 ** argument to callbacks registered using rtree_geometry_callback(). 11422 */ 11423 struct sqlite3_rtree_geometry { 11424 void *pContext; /* Copy of pContext passed to s_r_g_c() */ 11425 int nParam; /* Size of array aParam[] */ 11426 sqlite3_rtree_dbl *aParam; /* Parameters passed to SQL geom function */ 11427 void *pUser; /* Callback implementation user data */ 11428 void (*xDelUser)(void *); /* Called by SQLite to clean up pUser */ 11429 }; 11430 11431 /* 11432 ** Register a 2nd-generation geometry callback named zScore that can be 11433 ** used as part of an R-Tree geometry query as follows: 11434 ** 11435 ** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zQueryFunc(... params ...) 11436 */ 11437 SQLITE_API int sqlite3_rtree_query_callback( 11438 sqlite3 *db, 11439 const char *zQueryFunc, 11440 int (*xQueryFunc)(sqlite3_rtree_query_info*), 11441 void *pContext, 11442 void (*xDestructor)(void*) 11443 ); 11444 11445 11446 /* 11447 ** A pointer to a structure of the following type is passed as the 11448 ** argument to scored geometry callback registered using 11449 ** sqlite3_rtree_query_callback(). 11450 ** 11451 ** Note that the first 5 fields of this structure are identical to 11452 ** sqlite3_rtree_geometry. This structure is a subclass of 11453 ** sqlite3_rtree_geometry. 11454 */ 11455 struct sqlite3_rtree_query_info { 11456 void *pContext; /* pContext from when function registered */ 11457 int nParam; /* Number of function parameters */ 11458 sqlite3_rtree_dbl *aParam; /* value of function parameters */ 11459 void *pUser; /* callback can use this, if desired */ 11460 void (*xDelUser)(void*); /* function to free pUser */ 11461 sqlite3_rtree_dbl *aCoord; /* Coordinates of node or entry to check */ 11462 unsigned int *anQueue; /* Number of pending entries in the queue */ 11463 int nCoord; /* Number of coordinates */ 11464 int iLevel; /* Level of current node or entry */ 11465 int mxLevel; /* The largest iLevel value in the tree */ 11466 sqlite3_int64 iRowid; /* Rowid for current entry */ 11467 sqlite3_rtree_dbl rParentScore; /* Score of parent node */ 11468 int eParentWithin; /* Visibility of parent node */ 11469 int eWithin; /* OUT: Visibility */ 11470 sqlite3_rtree_dbl rScore; /* OUT: Write the score here */ 11471 /* The following fields are only available in 3.8.11 and later */ 11472 sqlite3_value **apSqlParam; /* Original SQL values of parameters */ 11473 }; 11474 11475 /* 11476 ** Allowed values for sqlite3_rtree_query.eWithin and .eParentWithin. 11477 */ 11478 #define NOT_WITHIN 0 /* Object completely outside of query region */ 11479 #define PARTLY_WITHIN 1 /* Object partially overlaps query region */ 11480 #define FULLY_WITHIN 2 /* Object fully contained within query region */ 11481 11482 11483 #ifdef __cplusplus 11484 } /* end of the 'extern "C"' block */ 11485 #endif 11486 11487 #endif /* ifndef _SQLITE3RTREE_H_ */ 11488 11489 /******** End of sqlite3rtree.h *********/ 11490 /******** Begin file sqlite3session.h *********/ 11491 11492 #if !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) 11493 #define __SQLITESESSION_H_ 1 11494 11495 /* 11496 ** Make sure we can call this stuff from C++. 11497 */ 11498 #ifdef __cplusplus 11499 extern "C" { 11500 #endif 11501 11502 11503 /* 11504 ** CAPI3REF: Session Object Handle 11505 ** 11506 ** An instance of this object is a [session] that can be used to 11507 ** record changes to a database. 11508 */ 11509 typedef struct sqlite3_session sqlite3_session; 11510 11511 /* 11512 ** CAPI3REF: Changeset Iterator Handle 11513 ** 11514 ** An instance of this object acts as a cursor for iterating 11515 ** over the elements of a [changeset] or [patchset]. 11516 */ 11517 typedef struct sqlite3_changeset_iter sqlite3_changeset_iter; 11518 11519 /* 11520 ** CAPI3REF: Create A New Session Object 11521 ** CONSTRUCTOR: sqlite3_session 11522 ** 11523 ** Create a new session object attached to database handle db. If successful, 11524 ** a pointer to the new object is written to *ppSession and SQLITE_OK is 11525 ** returned. If an error occurs, *ppSession is set to NULL and an SQLite 11526 ** error code (e.g. SQLITE_NOMEM) is returned. 11527 ** 11528 ** It is possible to create multiple session objects attached to a single 11529 ** database handle. 11530 ** 11531 ** Session objects created using this function should be deleted using the 11532 ** [sqlite3session_delete()] function before the database handle that they 11533 ** are attached to is itself closed. If the database handle is closed before 11534 ** the session object is deleted, then the results of calling any session 11535 ** module function, including [sqlite3session_delete()] on the session object 11536 ** are undefined. 11537 ** 11538 ** Because the session module uses the [sqlite3_preupdate_hook()] API, it 11539 ** is not possible for an application to register a pre-update hook on a 11540 ** database handle that has one or more session objects attached. Nor is 11541 ** it possible to create a session object attached to a database handle for 11542 ** which a pre-update hook is already defined. The results of attempting 11543 ** either of these things are undefined. 11544 ** 11545 ** The session object will be used to create changesets for tables in 11546 ** database zDb, where zDb is either "main", or "temp", or the name of an 11547 ** attached database. It is not an error if database zDb is not attached 11548 ** to the database when the session object is created. 11549 */ 11550 SQLITE_API int sqlite3session_create( 11551 sqlite3 *db, /* Database handle */ 11552 const char *zDb, /* Name of db (e.g. "main") */ 11553 sqlite3_session **ppSession /* OUT: New session object */ 11554 ); 11555 11556 /* 11557 ** CAPI3REF: Delete A Session Object 11558 ** DESTRUCTOR: sqlite3_session 11559 ** 11560 ** Delete a session object previously allocated using 11561 ** [sqlite3session_create()]. Once a session object has been deleted, the 11562 ** results of attempting to use pSession with any other session module 11563 ** function are undefined. 11564 ** 11565 ** Session objects must be deleted before the database handle to which they 11566 ** are attached is closed. Refer to the documentation for 11567 ** [sqlite3session_create()] for details. 11568 */ 11569 SQLITE_API void sqlite3session_delete(sqlite3_session *pSession); 11570 11571 /* 11572 ** CAPI3REF: Configure a Session Object 11573 ** METHOD: sqlite3_session 11574 ** 11575 ** This method is used to configure a session object after it has been 11576 ** created. At present the only valid values for the second parameter are 11577 ** [SQLITE_SESSION_OBJCONFIG_SIZE] and [SQLITE_SESSION_OBJCONFIG_ROWID]. 11578 ** 11579 */ 11580 SQLITE_API int sqlite3session_object_config(sqlite3_session*, int op, void *pArg); 11581 11582 /* 11583 ** CAPI3REF: Options for sqlite3session_object_config 11584 ** 11585 ** The following values may passed as the the 2nd parameter to 11586 ** sqlite3session_object_config(). 11587 ** 11588 ** <dt>SQLITE_SESSION_OBJCONFIG_SIZE <dd> 11589 ** This option is used to set, clear or query the flag that enables 11590 ** the [sqlite3session_changeset_size()] API. Because it imposes some 11591 ** computational overhead, this API is disabled by default. Argument 11592 ** pArg must point to a value of type (int). If the value is initially 11593 ** 0, then the sqlite3session_changeset_size() API is disabled. If it 11594 ** is greater than 0, then the same API is enabled. Or, if the initial 11595 ** value is less than zero, no change is made. In all cases the (int) 11596 ** variable is set to 1 if the sqlite3session_changeset_size() API is 11597 ** enabled following the current call, or 0 otherwise. 11598 ** 11599 ** It is an error (SQLITE_MISUSE) to attempt to modify this setting after 11600 ** the first table has been attached to the session object. 11601 ** 11602 ** <dt>SQLITE_SESSION_OBJCONFIG_ROWID <dd> 11603 ** This option is used to set, clear or query the flag that enables 11604 ** collection of data for tables with no explicit PRIMARY KEY. 11605 ** 11606 ** Normally, tables with no explicit PRIMARY KEY are simply ignored 11607 ** by the sessions module. However, if this flag is set, it behaves 11608 ** as if such tables have a column "_rowid_ INTEGER PRIMARY KEY" inserted 11609 ** as their leftmost columns. 11610 ** 11611 ** It is an error (SQLITE_MISUSE) to attempt to modify this setting after 11612 ** the first table has been attached to the session object. 11613 */ 11614 #define SQLITE_SESSION_OBJCONFIG_SIZE 1 11615 #define SQLITE_SESSION_OBJCONFIG_ROWID 2 11616 11617 /* 11618 ** CAPI3REF: Enable Or Disable A Session Object 11619 ** METHOD: sqlite3_session 11620 ** 11621 ** Enable or disable the recording of changes by a session object. When 11622 ** enabled, a session object records changes made to the database. When 11623 ** disabled - it does not. A newly created session object is enabled. 11624 ** Refer to the documentation for [sqlite3session_changeset()] for further 11625 ** details regarding how enabling and disabling a session object affects 11626 ** the eventual changesets. 11627 ** 11628 ** Passing zero to this function disables the session. Passing a value 11629 ** greater than zero enables it. Passing a value less than zero is a 11630 ** no-op, and may be used to query the current state of the session. 11631 ** 11632 ** The return value indicates the final state of the session object: 0 if 11633 ** the session is disabled, or 1 if it is enabled. 11634 */ 11635 SQLITE_API int sqlite3session_enable(sqlite3_session *pSession, int bEnable); 11636 11637 /* 11638 ** CAPI3REF: Set Or Clear the Indirect Change Flag 11639 ** METHOD: sqlite3_session 11640 ** 11641 ** Each change recorded by a session object is marked as either direct or 11642 ** indirect. A change is marked as indirect if either: 11643 ** 11644 ** <ul> 11645 ** <li> The session object "indirect" flag is set when the change is 11646 ** made, or 11647 ** <li> The change is made by an SQL trigger or foreign key action 11648 ** instead of directly as a result of a users SQL statement. 11649 ** </ul> 11650 ** 11651 ** If a single row is affected by more than one operation within a session, 11652 ** then the change is considered indirect if all operations meet the criteria 11653 ** for an indirect change above, or direct otherwise. 11654 ** 11655 ** This function is used to set, clear or query the session object indirect 11656 ** flag. If the second argument passed to this function is zero, then the 11657 ** indirect flag is cleared. If it is greater than zero, the indirect flag 11658 ** is set. Passing a value less than zero does not modify the current value 11659 ** of the indirect flag, and may be used to query the current state of the 11660 ** indirect flag for the specified session object. 11661 ** 11662 ** The return value indicates the final state of the indirect flag: 0 if 11663 ** it is clear, or 1 if it is set. 11664 */ 11665 SQLITE_API int sqlite3session_indirect(sqlite3_session *pSession, int bIndirect); 11666 11667 /* 11668 ** CAPI3REF: Attach A Table To A Session Object 11669 ** METHOD: sqlite3_session 11670 ** 11671 ** If argument zTab is not NULL, then it is the name of a table to attach 11672 ** to the session object passed as the first argument. All subsequent changes 11673 ** made to the table while the session object is enabled will be recorded. See 11674 ** documentation for [sqlite3session_changeset()] for further details. 11675 ** 11676 ** Or, if argument zTab is NULL, then changes are recorded for all tables 11677 ** in the database. If additional tables are added to the database (by 11678 ** executing "CREATE TABLE" statements) after this call is made, changes for 11679 ** the new tables are also recorded. 11680 ** 11681 ** Changes can only be recorded for tables that have a PRIMARY KEY explicitly 11682 ** defined as part of their CREATE TABLE statement. It does not matter if the 11683 ** PRIMARY KEY is an "INTEGER PRIMARY KEY" (rowid alias) or not. The PRIMARY 11684 ** KEY may consist of a single column, or may be a composite key. 11685 ** 11686 ** It is not an error if the named table does not exist in the database. Nor 11687 ** is it an error if the named table does not have a PRIMARY KEY. However, 11688 ** no changes will be recorded in either of these scenarios. 11689 ** 11690 ** Changes are not recorded for individual rows that have NULL values stored 11691 ** in one or more of their PRIMARY KEY columns. 11692 ** 11693 ** SQLITE_OK is returned if the call completes without error. Or, if an error 11694 ** occurs, an SQLite error code (e.g. SQLITE_NOMEM) is returned. 11695 ** 11696 ** <h3>Special sqlite_stat1 Handling</h3> 11697 ** 11698 ** As of SQLite version 3.22.0, the "sqlite_stat1" table is an exception to 11699 ** some of the rules above. In SQLite, the schema of sqlite_stat1 is: 11700 ** <pre> 11701 ** CREATE TABLE sqlite_stat1(tbl,idx,stat) 11702 ** </pre> 11703 ** 11704 ** Even though sqlite_stat1 does not have a PRIMARY KEY, changes are 11705 ** recorded for it as if the PRIMARY KEY is (tbl,idx). Additionally, changes 11706 ** are recorded for rows for which (idx IS NULL) is true. However, for such 11707 ** rows a zero-length blob (SQL value X'') is stored in the changeset or 11708 ** patchset instead of a NULL value. This allows such changesets to be 11709 ** manipulated by legacy implementations of sqlite3changeset_invert(), 11710 ** concat() and similar. 11711 ** 11712 ** The sqlite3changeset_apply() function automatically converts the 11713 ** zero-length blob back to a NULL value when updating the sqlite_stat1 11714 ** table. However, if the application calls sqlite3changeset_new(), 11715 ** sqlite3changeset_old() or sqlite3changeset_conflict on a changeset 11716 ** iterator directly (including on a changeset iterator passed to a 11717 ** conflict-handler callback) then the X'' value is returned. The application 11718 ** must translate X'' to NULL itself if required. 11719 ** 11720 ** Legacy (older than 3.22.0) versions of the sessions module cannot capture 11721 ** changes made to the sqlite_stat1 table. Legacy versions of the 11722 ** sqlite3changeset_apply() function silently ignore any modifications to the 11723 ** sqlite_stat1 table that are part of a changeset or patchset. 11724 */ 11725 SQLITE_API int sqlite3session_attach( 11726 sqlite3_session *pSession, /* Session object */ 11727 const char *zTab /* Table name */ 11728 ); 11729 11730 /* 11731 ** CAPI3REF: Set a table filter on a Session Object. 11732 ** METHOD: sqlite3_session 11733 ** 11734 ** The second argument (xFilter) is the "filter callback". For changes to rows 11735 ** in tables that are not attached to the Session object, the filter is called 11736 ** to determine whether changes to the table's rows should be tracked or not. 11737 ** If xFilter returns 0, changes are not tracked. Note that once a table is 11738 ** attached, xFilter will not be called again. 11739 */ 11740 SQLITE_API void sqlite3session_table_filter( 11741 sqlite3_session *pSession, /* Session object */ 11742 int(*xFilter)( 11743 void *pCtx, /* Copy of third arg to _filter_table() */ 11744 const char *zTab /* Table name */ 11745 ), 11746 void *pCtx /* First argument passed to xFilter */ 11747 ); 11748 11749 /* 11750 ** CAPI3REF: Generate A Changeset From A Session Object 11751 ** METHOD: sqlite3_session 11752 ** 11753 ** Obtain a changeset containing changes to the tables attached to the 11754 ** session object passed as the first argument. If successful, 11755 ** set *ppChangeset to point to a buffer containing the changeset 11756 ** and *pnChangeset to the size of the changeset in bytes before returning 11757 ** SQLITE_OK. If an error occurs, set both *ppChangeset and *pnChangeset to 11758 ** zero and return an SQLite error code. 11759 ** 11760 ** A changeset consists of zero or more INSERT, UPDATE and/or DELETE changes, 11761 ** each representing a change to a single row of an attached table. An INSERT 11762 ** change contains the values of each field of a new database row. A DELETE 11763 ** contains the original values of each field of a deleted database row. An 11764 ** UPDATE change contains the original values of each field of an updated 11765 ** database row along with the updated values for each updated non-primary-key 11766 ** column. It is not possible for an UPDATE change to represent a change that 11767 ** modifies the values of primary key columns. If such a change is made, it 11768 ** is represented in a changeset as a DELETE followed by an INSERT. 11769 ** 11770 ** Changes are not recorded for rows that have NULL values stored in one or 11771 ** more of their PRIMARY KEY columns. If such a row is inserted or deleted, 11772 ** no corresponding change is present in the changesets returned by this 11773 ** function. If an existing row with one or more NULL values stored in 11774 ** PRIMARY KEY columns is updated so that all PRIMARY KEY columns are non-NULL, 11775 ** only an INSERT is appears in the changeset. Similarly, if an existing row 11776 ** with non-NULL PRIMARY KEY values is updated so that one or more of its 11777 ** PRIMARY KEY columns are set to NULL, the resulting changeset contains a 11778 ** DELETE change only. 11779 ** 11780 ** The contents of a changeset may be traversed using an iterator created 11781 ** using the [sqlite3changeset_start()] API. A changeset may be applied to 11782 ** a database with a compatible schema using the [sqlite3changeset_apply()] 11783 ** API. 11784 ** 11785 ** Within a changeset generated by this function, all changes related to a 11786 ** single table are grouped together. In other words, when iterating through 11787 ** a changeset or when applying a changeset to a database, all changes related 11788 ** to a single table are processed before moving on to the next table. Tables 11789 ** are sorted in the same order in which they were attached (or auto-attached) 11790 ** to the sqlite3_session object. The order in which the changes related to 11791 ** a single table are stored is undefined. 11792 ** 11793 ** Following a successful call to this function, it is the responsibility of 11794 ** the caller to eventually free the buffer that *ppChangeset points to using 11795 ** [sqlite3_free()]. 11796 ** 11797 ** <h3>Changeset Generation</h3> 11798 ** 11799 ** Once a table has been attached to a session object, the session object 11800 ** records the primary key values of all new rows inserted into the table. 11801 ** It also records the original primary key and other column values of any 11802 ** deleted or updated rows. For each unique primary key value, data is only 11803 ** recorded once - the first time a row with said primary key is inserted, 11804 ** updated or deleted in the lifetime of the session. 11805 ** 11806 ** There is one exception to the previous paragraph: when a row is inserted, 11807 ** updated or deleted, if one or more of its primary key columns contain a 11808 ** NULL value, no record of the change is made. 11809 ** 11810 ** The session object therefore accumulates two types of records - those 11811 ** that consist of primary key values only (created when the user inserts 11812 ** a new record) and those that consist of the primary key values and the 11813 ** original values of other table columns (created when the users deletes 11814 ** or updates a record). 11815 ** 11816 ** When this function is called, the requested changeset is created using 11817 ** both the accumulated records and the current contents of the database 11818 ** file. Specifically: 11819 ** 11820 ** <ul> 11821 ** <li> For each record generated by an insert, the database is queried 11822 ** for a row with a matching primary key. If one is found, an INSERT 11823 ** change is added to the changeset. If no such row is found, no change 11824 ** is added to the changeset. 11825 ** 11826 ** <li> For each record generated by an update or delete, the database is 11827 ** queried for a row with a matching primary key. If such a row is 11828 ** found and one or more of the non-primary key fields have been 11829 ** modified from their original values, an UPDATE change is added to 11830 ** the changeset. Or, if no such row is found in the table, a DELETE 11831 ** change is added to the changeset. If there is a row with a matching 11832 ** primary key in the database, but all fields contain their original 11833 ** values, no change is added to the changeset. 11834 ** </ul> 11835 ** 11836 ** This means, amongst other things, that if a row is inserted and then later 11837 ** deleted while a session object is active, neither the insert nor the delete 11838 ** will be present in the changeset. Or if a row is deleted and then later a 11839 ** row with the same primary key values inserted while a session object is 11840 ** active, the resulting changeset will contain an UPDATE change instead of 11841 ** a DELETE and an INSERT. 11842 ** 11843 ** When a session object is disabled (see the [sqlite3session_enable()] API), 11844 ** it does not accumulate records when rows are inserted, updated or deleted. 11845 ** This may appear to have some counter-intuitive effects if a single row 11846 ** is written to more than once during a session. For example, if a row 11847 ** is inserted while a session object is enabled, then later deleted while 11848 ** the same session object is disabled, no INSERT record will appear in the 11849 ** changeset, even though the delete took place while the session was disabled. 11850 ** Or, if one field of a row is updated while a session is enabled, and 11851 ** then another field of the same row is updated while the session is disabled, 11852 ** the resulting changeset will contain an UPDATE change that updates both 11853 ** fields. 11854 */ 11855 SQLITE_API int sqlite3session_changeset( 11856 sqlite3_session *pSession, /* Session object */ 11857 int *pnChangeset, /* OUT: Size of buffer at *ppChangeset */ 11858 void **ppChangeset /* OUT: Buffer containing changeset */ 11859 ); 11860 11861 /* 11862 ** CAPI3REF: Return An Upper-limit For The Size Of The Changeset 11863 ** METHOD: sqlite3_session 11864 ** 11865 ** By default, this function always returns 0. For it to return 11866 ** a useful result, the sqlite3_session object must have been configured 11867 ** to enable this API using sqlite3session_object_config() with the 11868 ** SQLITE_SESSION_OBJCONFIG_SIZE verb. 11869 ** 11870 ** When enabled, this function returns an upper limit, in bytes, for the size 11871 ** of the changeset that might be produced if sqlite3session_changeset() were 11872 ** called. The final changeset size might be equal to or smaller than the 11873 ** size in bytes returned by this function. 11874 */ 11875 SQLITE_API sqlite3_int64 sqlite3session_changeset_size(sqlite3_session *pSession); 11876 11877 /* 11878 ** CAPI3REF: Load The Difference Between Tables Into A Session 11879 ** METHOD: sqlite3_session 11880 ** 11881 ** If it is not already attached to the session object passed as the first 11882 ** argument, this function attaches table zTbl in the same manner as the 11883 ** [sqlite3session_attach()] function. If zTbl does not exist, or if it 11884 ** does not have a primary key, this function is a no-op (but does not return 11885 ** an error). 11886 ** 11887 ** Argument zFromDb must be the name of a database ("main", "temp" etc.) 11888 ** attached to the same database handle as the session object that contains 11889 ** a table compatible with the table attached to the session by this function. 11890 ** A table is considered compatible if it: 11891 ** 11892 ** <ul> 11893 ** <li> Has the same name, 11894 ** <li> Has the same set of columns declared in the same order, and 11895 ** <li> Has the same PRIMARY KEY definition. 11896 ** </ul> 11897 ** 11898 ** If the tables are not compatible, SQLITE_SCHEMA is returned. If the tables 11899 ** are compatible but do not have any PRIMARY KEY columns, it is not an error 11900 ** but no changes are added to the session object. As with other session 11901 ** APIs, tables without PRIMARY KEYs are simply ignored. 11902 ** 11903 ** This function adds a set of changes to the session object that could be 11904 ** used to update the table in database zFrom (call this the "from-table") 11905 ** so that its content is the same as the table attached to the session 11906 ** object (call this the "to-table"). Specifically: 11907 ** 11908 ** <ul> 11909 ** <li> For each row (primary key) that exists in the to-table but not in 11910 ** the from-table, an INSERT record is added to the session object. 11911 ** 11912 ** <li> For each row (primary key) that exists in the to-table but not in 11913 ** the from-table, a DELETE record is added to the session object. 11914 ** 11915 ** <li> For each row (primary key) that exists in both tables, but features 11916 ** different non-PK values in each, an UPDATE record is added to the 11917 ** session. 11918 ** </ul> 11919 ** 11920 ** To clarify, if this function is called and then a changeset constructed 11921 ** using [sqlite3session_changeset()], then after applying that changeset to 11922 ** database zFrom the contents of the two compatible tables would be 11923 ** identical. 11924 ** 11925 ** Unless the call to this function is a no-op as described above, it is an 11926 ** error if database zFrom does not exist or does not contain the required 11927 ** compatible table. 11928 ** 11929 ** If the operation is successful, SQLITE_OK is returned. Otherwise, an SQLite 11930 ** error code. In this case, if argument pzErrMsg is not NULL, *pzErrMsg 11931 ** may be set to point to a buffer containing an English language error 11932 ** message. It is the responsibility of the caller to free this buffer using 11933 ** sqlite3_free(). 11934 */ 11935 SQLITE_API int sqlite3session_diff( 11936 sqlite3_session *pSession, 11937 const char *zFromDb, 11938 const char *zTbl, 11939 char **pzErrMsg 11940 ); 11941 11942 11943 /* 11944 ** CAPI3REF: Generate A Patchset From A Session Object 11945 ** METHOD: sqlite3_session 11946 ** 11947 ** The differences between a patchset and a changeset are that: 11948 ** 11949 ** <ul> 11950 ** <li> DELETE records consist of the primary key fields only. The 11951 ** original values of other fields are omitted. 11952 ** <li> The original values of any modified fields are omitted from 11953 ** UPDATE records. 11954 ** </ul> 11955 ** 11956 ** A patchset blob may be used with up to date versions of all 11957 ** sqlite3changeset_xxx API functions except for sqlite3changeset_invert(), 11958 ** which returns SQLITE_CORRUPT if it is passed a patchset. Similarly, 11959 ** attempting to use a patchset blob with old versions of the 11960 ** sqlite3changeset_xxx APIs also provokes an SQLITE_CORRUPT error. 11961 ** 11962 ** Because the non-primary key "old.*" fields are omitted, no 11963 ** SQLITE_CHANGESET_DATA conflicts can be detected or reported if a patchset 11964 ** is passed to the sqlite3changeset_apply() API. Other conflict types work 11965 ** in the same way as for changesets. 11966 ** 11967 ** Changes within a patchset are ordered in the same way as for changesets 11968 ** generated by the sqlite3session_changeset() function (i.e. all changes for 11969 ** a single table are grouped together, tables appear in the order in which 11970 ** they were attached to the session object). 11971 */ 11972 SQLITE_API int sqlite3session_patchset( 11973 sqlite3_session *pSession, /* Session object */ 11974 int *pnPatchset, /* OUT: Size of buffer at *ppPatchset */ 11975 void **ppPatchset /* OUT: Buffer containing patchset */ 11976 ); 11977 11978 /* 11979 ** CAPI3REF: Test if a changeset has recorded any changes. 11980 ** 11981 ** Return non-zero if no changes to attached tables have been recorded by 11982 ** the session object passed as the first argument. Otherwise, if one or 11983 ** more changes have been recorded, return zero. 11984 ** 11985 ** Even if this function returns zero, it is possible that calling 11986 ** [sqlite3session_changeset()] on the session handle may still return a 11987 ** changeset that contains no changes. This can happen when a row in 11988 ** an attached table is modified and then later on the original values 11989 ** are restored. However, if this function returns non-zero, then it is 11990 ** guaranteed that a call to sqlite3session_changeset() will return a 11991 ** changeset containing zero changes. 11992 */ 11993 SQLITE_API int sqlite3session_isempty(sqlite3_session *pSession); 11994 11995 /* 11996 ** CAPI3REF: Query for the amount of heap memory used by a session object. 11997 ** 11998 ** This API returns the total amount of heap memory in bytes currently 11999 ** used by the session object passed as the only argument. 12000 */ 12001 SQLITE_API sqlite3_int64 sqlite3session_memory_used(sqlite3_session *pSession); 12002 12003 /* 12004 ** CAPI3REF: Create An Iterator To Traverse A Changeset 12005 ** CONSTRUCTOR: sqlite3_changeset_iter 12006 ** 12007 ** Create an iterator used to iterate through the contents of a changeset. 12008 ** If successful, *pp is set to point to the iterator handle and SQLITE_OK 12009 ** is returned. Otherwise, if an error occurs, *pp is set to zero and an 12010 ** SQLite error code is returned. 12011 ** 12012 ** The following functions can be used to advance and query a changeset 12013 ** iterator created by this function: 12014 ** 12015 ** <ul> 12016 ** <li> [sqlite3changeset_next()] 12017 ** <li> [sqlite3changeset_op()] 12018 ** <li> [sqlite3changeset_new()] 12019 ** <li> [sqlite3changeset_old()] 12020 ** </ul> 12021 ** 12022 ** It is the responsibility of the caller to eventually destroy the iterator 12023 ** by passing it to [sqlite3changeset_finalize()]. The buffer containing the 12024 ** changeset (pChangeset) must remain valid until after the iterator is 12025 ** destroyed. 12026 ** 12027 ** Assuming the changeset blob was created by one of the 12028 ** [sqlite3session_changeset()], [sqlite3changeset_concat()] or 12029 ** [sqlite3changeset_invert()] functions, all changes within the changeset 12030 ** that apply to a single table are grouped together. This means that when 12031 ** an application iterates through a changeset using an iterator created by 12032 ** this function, all changes that relate to a single table are visited 12033 ** consecutively. There is no chance that the iterator will visit a change 12034 ** the applies to table X, then one for table Y, and then later on visit 12035 ** another change for table X. 12036 ** 12037 ** The behavior of sqlite3changeset_start_v2() and its streaming equivalent 12038 ** may be modified by passing a combination of 12039 ** [SQLITE_CHANGESETSTART_INVERT | supported flags] as the 4th parameter. 12040 ** 12041 ** Note that the sqlite3changeset_start_v2() API is still <b>experimental</b> 12042 ** and therefore subject to change. 12043 */ 12044 SQLITE_API int sqlite3changeset_start( 12045 sqlite3_changeset_iter **pp, /* OUT: New changeset iterator handle */ 12046 int nChangeset, /* Size of changeset blob in bytes */ 12047 void *pChangeset /* Pointer to blob containing changeset */ 12048 ); 12049 SQLITE_API int sqlite3changeset_start_v2( 12050 sqlite3_changeset_iter **pp, /* OUT: New changeset iterator handle */ 12051 int nChangeset, /* Size of changeset blob in bytes */ 12052 void *pChangeset, /* Pointer to blob containing changeset */ 12053 int flags /* SESSION_CHANGESETSTART_* flags */ 12054 ); 12055 12056 /* 12057 ** CAPI3REF: Flags for sqlite3changeset_start_v2 12058 ** 12059 ** The following flags may passed via the 4th parameter to 12060 ** [sqlite3changeset_start_v2] and [sqlite3changeset_start_v2_strm]: 12061 ** 12062 ** <dt>SQLITE_CHANGESETSTART_INVERT <dd> 12063 ** Invert the changeset while iterating through it. This is equivalent to 12064 ** inverting a changeset using sqlite3changeset_invert() before applying it. 12065 ** It is an error to specify this flag with a patchset. 12066 */ 12067 #define SQLITE_CHANGESETSTART_INVERT 0x0002 12068 12069 12070 /* 12071 ** CAPI3REF: Advance A Changeset Iterator 12072 ** METHOD: sqlite3_changeset_iter 12073 ** 12074 ** This function may only be used with iterators created by the function 12075 ** [sqlite3changeset_start()]. If it is called on an iterator passed to 12076 ** a conflict-handler callback by [sqlite3changeset_apply()], SQLITE_MISUSE 12077 ** is returned and the call has no effect. 12078 ** 12079 ** Immediately after an iterator is created by sqlite3changeset_start(), it 12080 ** does not point to any change in the changeset. Assuming the changeset 12081 ** is not empty, the first call to this function advances the iterator to 12082 ** point to the first change in the changeset. Each subsequent call advances 12083 ** the iterator to point to the next change in the changeset (if any). If 12084 ** no error occurs and the iterator points to a valid change after a call 12085 ** to sqlite3changeset_next() has advanced it, SQLITE_ROW is returned. 12086 ** Otherwise, if all changes in the changeset have already been visited, 12087 ** SQLITE_DONE is returned. 12088 ** 12089 ** If an error occurs, an SQLite error code is returned. Possible error 12090 ** codes include SQLITE_CORRUPT (if the changeset buffer is corrupt) or 12091 ** SQLITE_NOMEM. 12092 */ 12093 SQLITE_API int sqlite3changeset_next(sqlite3_changeset_iter *pIter); 12094 12095 /* 12096 ** CAPI3REF: Obtain The Current Operation From A Changeset Iterator 12097 ** METHOD: sqlite3_changeset_iter 12098 ** 12099 ** The pIter argument passed to this function may either be an iterator 12100 ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator 12101 ** created by [sqlite3changeset_start()]. In the latter case, the most recent 12102 ** call to [sqlite3changeset_next()] must have returned [SQLITE_ROW]. If this 12103 ** is not the case, this function returns [SQLITE_MISUSE]. 12104 ** 12105 ** Arguments pOp, pnCol and pzTab may not be NULL. Upon return, three 12106 ** outputs are set through these pointers: 12107 ** 12108 ** *pOp is set to one of [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE], 12109 ** depending on the type of change that the iterator currently points to; 12110 ** 12111 ** *pnCol is set to the number of columns in the table affected by the change; and 12112 ** 12113 ** *pzTab is set to point to a nul-terminated utf-8 encoded string containing 12114 ** the name of the table affected by the current change. The buffer remains 12115 ** valid until either sqlite3changeset_next() is called on the iterator 12116 ** or until the conflict-handler function returns. 12117 ** 12118 ** If pbIndirect is not NULL, then *pbIndirect is set to true (1) if the change 12119 ** is an indirect change, or false (0) otherwise. See the documentation for 12120 ** [sqlite3session_indirect()] for a description of direct and indirect 12121 ** changes. 12122 ** 12123 ** If no error occurs, SQLITE_OK is returned. If an error does occur, an 12124 ** SQLite error code is returned. The values of the output variables may not 12125 ** be trusted in this case. 12126 */ 12127 SQLITE_API int sqlite3changeset_op( 12128 sqlite3_changeset_iter *pIter, /* Iterator object */ 12129 const char **pzTab, /* OUT: Pointer to table name */ 12130 int *pnCol, /* OUT: Number of columns in table */ 12131 int *pOp, /* OUT: SQLITE_INSERT, DELETE or UPDATE */ 12132 int *pbIndirect /* OUT: True for an 'indirect' change */ 12133 ); 12134 12135 /* 12136 ** CAPI3REF: Obtain The Primary Key Definition Of A Table 12137 ** METHOD: sqlite3_changeset_iter 12138 ** 12139 ** For each modified table, a changeset includes the following: 12140 ** 12141 ** <ul> 12142 ** <li> The number of columns in the table, and 12143 ** <li> Which of those columns make up the tables PRIMARY KEY. 12144 ** </ul> 12145 ** 12146 ** This function is used to find which columns comprise the PRIMARY KEY of 12147 ** the table modified by the change that iterator pIter currently points to. 12148 ** If successful, *pabPK is set to point to an array of nCol entries, where 12149 ** nCol is the number of columns in the table. Elements of *pabPK are set to 12150 ** 0x01 if the corresponding column is part of the tables primary key, or 12151 ** 0x00 if it is not. 12152 ** 12153 ** If argument pnCol is not NULL, then *pnCol is set to the number of columns 12154 ** in the table. 12155 ** 12156 ** If this function is called when the iterator does not point to a valid 12157 ** entry, SQLITE_MISUSE is returned and the output variables zeroed. Otherwise, 12158 ** SQLITE_OK is returned and the output variables populated as described 12159 ** above. 12160 */ 12161 SQLITE_API int sqlite3changeset_pk( 12162 sqlite3_changeset_iter *pIter, /* Iterator object */ 12163 unsigned char **pabPK, /* OUT: Array of boolean - true for PK cols */ 12164 int *pnCol /* OUT: Number of entries in output array */ 12165 ); 12166 12167 /* 12168 ** CAPI3REF: Obtain old.* Values From A Changeset Iterator 12169 ** METHOD: sqlite3_changeset_iter 12170 ** 12171 ** The pIter argument passed to this function may either be an iterator 12172 ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator 12173 ** created by [sqlite3changeset_start()]. In the latter case, the most recent 12174 ** call to [sqlite3changeset_next()] must have returned SQLITE_ROW. 12175 ** Furthermore, it may only be called if the type of change that the iterator 12176 ** currently points to is either [SQLITE_DELETE] or [SQLITE_UPDATE]. Otherwise, 12177 ** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL. 12178 ** 12179 ** Argument iVal must be greater than or equal to 0, and less than the number 12180 ** of columns in the table affected by the current change. Otherwise, 12181 ** [SQLITE_RANGE] is returned and *ppValue is set to NULL. 12182 ** 12183 ** If successful, this function sets *ppValue to point to a protected 12184 ** sqlite3_value object containing the iVal'th value from the vector of 12185 ** original row values stored as part of the UPDATE or DELETE change and 12186 ** returns SQLITE_OK. The name of the function comes from the fact that this 12187 ** is similar to the "old.*" columns available to update or delete triggers. 12188 ** 12189 ** If some other error occurs (e.g. an OOM condition), an SQLite error code 12190 ** is returned and *ppValue is set to NULL. 12191 */ 12192 SQLITE_API int sqlite3changeset_old( 12193 sqlite3_changeset_iter *pIter, /* Changeset iterator */ 12194 int iVal, /* Column number */ 12195 sqlite3_value **ppValue /* OUT: Old value (or NULL pointer) */ 12196 ); 12197 12198 /* 12199 ** CAPI3REF: Obtain new.* Values From A Changeset Iterator 12200 ** METHOD: sqlite3_changeset_iter 12201 ** 12202 ** The pIter argument passed to this function may either be an iterator 12203 ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator 12204 ** created by [sqlite3changeset_start()]. In the latter case, the most recent 12205 ** call to [sqlite3changeset_next()] must have returned SQLITE_ROW. 12206 ** Furthermore, it may only be called if the type of change that the iterator 12207 ** currently points to is either [SQLITE_UPDATE] or [SQLITE_INSERT]. Otherwise, 12208 ** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL. 12209 ** 12210 ** Argument iVal must be greater than or equal to 0, and less than the number 12211 ** of columns in the table affected by the current change. Otherwise, 12212 ** [SQLITE_RANGE] is returned and *ppValue is set to NULL. 12213 ** 12214 ** If successful, this function sets *ppValue to point to a protected 12215 ** sqlite3_value object containing the iVal'th value from the vector of 12216 ** new row values stored as part of the UPDATE or INSERT change and 12217 ** returns SQLITE_OK. If the change is an UPDATE and does not include 12218 ** a new value for the requested column, *ppValue is set to NULL and 12219 ** SQLITE_OK returned. The name of the function comes from the fact that 12220 ** this is similar to the "new.*" columns available to update or delete 12221 ** triggers. 12222 ** 12223 ** If some other error occurs (e.g. an OOM condition), an SQLite error code 12224 ** is returned and *ppValue is set to NULL. 12225 */ 12226 SQLITE_API int sqlite3changeset_new( 12227 sqlite3_changeset_iter *pIter, /* Changeset iterator */ 12228 int iVal, /* Column number */ 12229 sqlite3_value **ppValue /* OUT: New value (or NULL pointer) */ 12230 ); 12231 12232 /* 12233 ** CAPI3REF: Obtain Conflicting Row Values From A Changeset Iterator 12234 ** METHOD: sqlite3_changeset_iter 12235 ** 12236 ** This function should only be used with iterator objects passed to a 12237 ** conflict-handler callback by [sqlite3changeset_apply()] with either 12238 ** [SQLITE_CHANGESET_DATA] or [SQLITE_CHANGESET_CONFLICT]. If this function 12239 ** is called on any other iterator, [SQLITE_MISUSE] is returned and *ppValue 12240 ** is set to NULL. 12241 ** 12242 ** Argument iVal must be greater than or equal to 0, and less than the number 12243 ** of columns in the table affected by the current change. Otherwise, 12244 ** [SQLITE_RANGE] is returned and *ppValue is set to NULL. 12245 ** 12246 ** If successful, this function sets *ppValue to point to a protected 12247 ** sqlite3_value object containing the iVal'th value from the 12248 ** "conflicting row" associated with the current conflict-handler callback 12249 ** and returns SQLITE_OK. 12250 ** 12251 ** If some other error occurs (e.g. an OOM condition), an SQLite error code 12252 ** is returned and *ppValue is set to NULL. 12253 */ 12254 SQLITE_API int sqlite3changeset_conflict( 12255 sqlite3_changeset_iter *pIter, /* Changeset iterator */ 12256 int iVal, /* Column number */ 12257 sqlite3_value **ppValue /* OUT: Value from conflicting row */ 12258 ); 12259 12260 /* 12261 ** CAPI3REF: Determine The Number Of Foreign Key Constraint Violations 12262 ** METHOD: sqlite3_changeset_iter 12263 ** 12264 ** This function may only be called with an iterator passed to an 12265 ** SQLITE_CHANGESET_FOREIGN_KEY conflict handler callback. In this case 12266 ** it sets the output variable to the total number of known foreign key 12267 ** violations in the destination database and returns SQLITE_OK. 12268 ** 12269 ** In all other cases this function returns SQLITE_MISUSE. 12270 */ 12271 SQLITE_API int sqlite3changeset_fk_conflicts( 12272 sqlite3_changeset_iter *pIter, /* Changeset iterator */ 12273 int *pnOut /* OUT: Number of FK violations */ 12274 ); 12275 12276 12277 /* 12278 ** CAPI3REF: Finalize A Changeset Iterator 12279 ** METHOD: sqlite3_changeset_iter 12280 ** 12281 ** This function is used to finalize an iterator allocated with 12282 ** [sqlite3changeset_start()]. 12283 ** 12284 ** This function should only be called on iterators created using the 12285 ** [sqlite3changeset_start()] function. If an application calls this 12286 ** function with an iterator passed to a conflict-handler by 12287 ** [sqlite3changeset_apply()], [SQLITE_MISUSE] is immediately returned and the 12288 ** call has no effect. 12289 ** 12290 ** If an error was encountered within a call to an sqlite3changeset_xxx() 12291 ** function (for example an [SQLITE_CORRUPT] in [sqlite3changeset_next()] or an 12292 ** [SQLITE_NOMEM] in [sqlite3changeset_new()]) then an error code corresponding 12293 ** to that error is returned by this function. Otherwise, SQLITE_OK is 12294 ** returned. This is to allow the following pattern (pseudo-code): 12295 ** 12296 ** <pre> 12297 ** sqlite3changeset_start(); 12298 ** while( SQLITE_ROW==sqlite3changeset_next() ){ 12299 ** // Do something with change. 12300 ** } 12301 ** rc = sqlite3changeset_finalize(); 12302 ** if( rc!=SQLITE_OK ){ 12303 ** // An error has occurred 12304 ** } 12305 ** </pre> 12306 */ 12307 SQLITE_API int sqlite3changeset_finalize(sqlite3_changeset_iter *pIter); 12308 12309 /* 12310 ** CAPI3REF: Invert A Changeset 12311 ** 12312 ** This function is used to "invert" a changeset object. Applying an inverted 12313 ** changeset to a database reverses the effects of applying the uninverted 12314 ** changeset. Specifically: 12315 ** 12316 ** <ul> 12317 ** <li> Each DELETE change is changed to an INSERT, and 12318 ** <li> Each INSERT change is changed to a DELETE, and 12319 ** <li> For each UPDATE change, the old.* and new.* values are exchanged. 12320 ** </ul> 12321 ** 12322 ** This function does not change the order in which changes appear within 12323 ** the changeset. It merely reverses the sense of each individual change. 12324 ** 12325 ** If successful, a pointer to a buffer containing the inverted changeset 12326 ** is stored in *ppOut, the size of the same buffer is stored in *pnOut, and 12327 ** SQLITE_OK is returned. If an error occurs, both *pnOut and *ppOut are 12328 ** zeroed and an SQLite error code returned. 12329 ** 12330 ** It is the responsibility of the caller to eventually call sqlite3_free() 12331 ** on the *ppOut pointer to free the buffer allocation following a successful 12332 ** call to this function. 12333 ** 12334 ** WARNING/TODO: This function currently assumes that the input is a valid 12335 ** changeset. If it is not, the results are undefined. 12336 */ 12337 SQLITE_API int sqlite3changeset_invert( 12338 int nIn, const void *pIn, /* Input changeset */ 12339 int *pnOut, void **ppOut /* OUT: Inverse of input */ 12340 ); 12341 12342 /* 12343 ** CAPI3REF: Concatenate Two Changeset Objects 12344 ** 12345 ** This function is used to concatenate two changesets, A and B, into a 12346 ** single changeset. The result is a changeset equivalent to applying 12347 ** changeset A followed by changeset B. 12348 ** 12349 ** This function combines the two input changesets using an 12350 ** sqlite3_changegroup object. Calling it produces similar results as the 12351 ** following code fragment: 12352 ** 12353 ** <pre> 12354 ** sqlite3_changegroup *pGrp; 12355 ** rc = sqlite3_changegroup_new(&pGrp); 12356 ** if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nA, pA); 12357 ** if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nB, pB); 12358 ** if( rc==SQLITE_OK ){ 12359 ** rc = sqlite3changegroup_output(pGrp, pnOut, ppOut); 12360 ** }else{ 12361 ** *ppOut = 0; 12362 ** *pnOut = 0; 12363 ** } 12364 ** </pre> 12365 ** 12366 ** Refer to the sqlite3_changegroup documentation below for details. 12367 */ 12368 SQLITE_API int sqlite3changeset_concat( 12369 int nA, /* Number of bytes in buffer pA */ 12370 void *pA, /* Pointer to buffer containing changeset A */ 12371 int nB, /* Number of bytes in buffer pB */ 12372 void *pB, /* Pointer to buffer containing changeset B */ 12373 int *pnOut, /* OUT: Number of bytes in output changeset */ 12374 void **ppOut /* OUT: Buffer containing output changeset */ 12375 ); 12376 12377 /* 12378 ** CAPI3REF: Changegroup Handle 12379 ** 12380 ** A changegroup is an object used to combine two or more 12381 ** [changesets] or [patchsets] 12382 */ 12383 typedef struct sqlite3_changegroup sqlite3_changegroup; 12384 12385 /* 12386 ** CAPI3REF: Create A New Changegroup Object 12387 ** CONSTRUCTOR: sqlite3_changegroup 12388 ** 12389 ** An sqlite3_changegroup object is used to combine two or more changesets 12390 ** (or patchsets) into a single changeset (or patchset). A single changegroup 12391 ** object may combine changesets or patchsets, but not both. The output is 12392 ** always in the same format as the input. 12393 ** 12394 ** If successful, this function returns SQLITE_OK and populates (*pp) with 12395 ** a pointer to a new sqlite3_changegroup object before returning. The caller 12396 ** should eventually free the returned object using a call to 12397 ** sqlite3changegroup_delete(). If an error occurs, an SQLite error code 12398 ** (i.e. SQLITE_NOMEM) is returned and *pp is set to NULL. 12399 ** 12400 ** The usual usage pattern for an sqlite3_changegroup object is as follows: 12401 ** 12402 ** <ul> 12403 ** <li> It is created using a call to sqlite3changegroup_new(). 12404 ** 12405 ** <li> Zero or more changesets (or patchsets) are added to the object 12406 ** by calling sqlite3changegroup_add(). 12407 ** 12408 ** <li> The result of combining all input changesets together is obtained 12409 ** by the application via a call to sqlite3changegroup_output(). 12410 ** 12411 ** <li> The object is deleted using a call to sqlite3changegroup_delete(). 12412 ** </ul> 12413 ** 12414 ** Any number of calls to add() and output() may be made between the calls to 12415 ** new() and delete(), and in any order. 12416 ** 12417 ** As well as the regular sqlite3changegroup_add() and 12418 ** sqlite3changegroup_output() functions, also available are the streaming 12419 ** versions sqlite3changegroup_add_strm() and sqlite3changegroup_output_strm(). 12420 */ 12421 SQLITE_API int sqlite3changegroup_new(sqlite3_changegroup **pp); 12422 12423 /* 12424 ** CAPI3REF: Add a Schema to a Changegroup 12425 ** METHOD: sqlite3_changegroup_schema 12426 ** 12427 ** This method may be used to optionally enforce the rule that the changesets 12428 ** added to the changegroup handle must match the schema of database zDb 12429 ** ("main", "temp", or the name of an attached database). If 12430 ** sqlite3changegroup_add() is called to add a changeset that is not compatible 12431 ** with the configured schema, SQLITE_SCHEMA is returned and the changegroup 12432 ** object is left in an undefined state. 12433 ** 12434 ** A changeset schema is considered compatible with the database schema in 12435 ** the same way as for sqlite3changeset_apply(). Specifically, for each 12436 ** table in the changeset, there exists a database table with: 12437 ** 12438 ** <ul> 12439 ** <li> The name identified by the changeset, and 12440 ** <li> at least as many columns as recorded in the changeset, and 12441 ** <li> the primary key columns in the same position as recorded in 12442 ** the changeset. 12443 ** </ul> 12444 ** 12445 ** The output of the changegroup object always has the same schema as the 12446 ** database nominated using this function. In cases where changesets passed 12447 ** to sqlite3changegroup_add() have fewer columns than the corresponding table 12448 ** in the database schema, these are filled in using the default column 12449 ** values from the database schema. This makes it possible to combined 12450 ** changesets that have different numbers of columns for a single table 12451 ** within a changegroup, provided that they are otherwise compatible. 12452 */ 12453 SQLITE_API int sqlite3changegroup_schema(sqlite3_changegroup*, sqlite3*, const char *zDb); 12454 12455 /* 12456 ** CAPI3REF: Add A Changeset To A Changegroup 12457 ** METHOD: sqlite3_changegroup 12458 ** 12459 ** Add all changes within the changeset (or patchset) in buffer pData (size 12460 ** nData bytes) to the changegroup. 12461 ** 12462 ** If the buffer contains a patchset, then all prior calls to this function 12463 ** on the same changegroup object must also have specified patchsets. Or, if 12464 ** the buffer contains a changeset, so must have the earlier calls to this 12465 ** function. Otherwise, SQLITE_ERROR is returned and no changes are added 12466 ** to the changegroup. 12467 ** 12468 ** Rows within the changeset and changegroup are identified by the values in 12469 ** their PRIMARY KEY columns. A change in the changeset is considered to 12470 ** apply to the same row as a change already present in the changegroup if 12471 ** the two rows have the same primary key. 12472 ** 12473 ** Changes to rows that do not already appear in the changegroup are 12474 ** simply copied into it. Or, if both the new changeset and the changegroup 12475 ** contain changes that apply to a single row, the final contents of the 12476 ** changegroup depends on the type of each change, as follows: 12477 ** 12478 ** <table border=1 style="margin-left:8ex;margin-right:8ex"> 12479 ** <tr><th style="white-space:pre">Existing Change </th> 12480 ** <th style="white-space:pre">New Change </th> 12481 ** <th>Output Change 12482 ** <tr><td>INSERT <td>INSERT <td> 12483 ** The new change is ignored. This case does not occur if the new 12484 ** changeset was recorded immediately after the changesets already 12485 ** added to the changegroup. 12486 ** <tr><td>INSERT <td>UPDATE <td> 12487 ** The INSERT change remains in the changegroup. The values in the 12488 ** INSERT change are modified as if the row was inserted by the 12489 ** existing change and then updated according to the new change. 12490 ** <tr><td>INSERT <td>DELETE <td> 12491 ** The existing INSERT is removed from the changegroup. The DELETE is 12492 ** not added. 12493 ** <tr><td>UPDATE <td>INSERT <td> 12494 ** The new change is ignored. This case does not occur if the new 12495 ** changeset was recorded immediately after the changesets already 12496 ** added to the changegroup. 12497 ** <tr><td>UPDATE <td>UPDATE <td> 12498 ** The existing UPDATE remains within the changegroup. It is amended 12499 ** so that the accompanying values are as if the row was updated once 12500 ** by the existing change and then again by the new change. 12501 ** <tr><td>UPDATE <td>DELETE <td> 12502 ** The existing UPDATE is replaced by the new DELETE within the 12503 ** changegroup. 12504 ** <tr><td>DELETE <td>INSERT <td> 12505 ** If one or more of the column values in the row inserted by the 12506 ** new change differ from those in the row deleted by the existing 12507 ** change, the existing DELETE is replaced by an UPDATE within the 12508 ** changegroup. Otherwise, if the inserted row is exactly the same 12509 ** as the deleted row, the existing DELETE is simply discarded. 12510 ** <tr><td>DELETE <td>UPDATE <td> 12511 ** The new change is ignored. This case does not occur if the new 12512 ** changeset was recorded immediately after the changesets already 12513 ** added to the changegroup. 12514 ** <tr><td>DELETE <td>DELETE <td> 12515 ** The new change is ignored. This case does not occur if the new 12516 ** changeset was recorded immediately after the changesets already 12517 ** added to the changegroup. 12518 ** </table> 12519 ** 12520 ** If the new changeset contains changes to a table that is already present 12521 ** in the changegroup, then the number of columns and the position of the 12522 ** primary key columns for the table must be consistent. If this is not the 12523 ** case, this function fails with SQLITE_SCHEMA. Except, if the changegroup 12524 ** object has been configured with a database schema using the 12525 ** sqlite3changegroup_schema() API, then it is possible to combine changesets 12526 ** with different numbers of columns for a single table, provided that 12527 ** they are otherwise compatible. 12528 ** 12529 ** If the input changeset appears to be corrupt and the corruption is 12530 ** detected, SQLITE_CORRUPT is returned. Or, if an out-of-memory condition 12531 ** occurs during processing, this function returns SQLITE_NOMEM. 12532 ** 12533 ** In all cases, if an error occurs the state of the final contents of the 12534 ** changegroup is undefined. If no error occurs, SQLITE_OK is returned. 12535 */ 12536 SQLITE_API int sqlite3changegroup_add(sqlite3_changegroup*, int nData, void *pData); 12537 12538 /* 12539 ** CAPI3REF: Add A Single Change To A Changegroup 12540 ** METHOD: sqlite3_changegroup 12541 ** 12542 ** This function adds the single change currently indicated by the iterator 12543 ** passed as the second argument to the changegroup object. The rules for 12544 ** adding the change are just as described for [sqlite3changegroup_add()]. 12545 ** 12546 ** If the change is successfully added to the changegroup, SQLITE_OK is 12547 ** returned. Otherwise, an SQLite error code is returned. 12548 ** 12549 ** The iterator must point to a valid entry when this function is called. 12550 ** If it does not, SQLITE_ERROR is returned and no change is added to the 12551 ** changegroup. Additionally, the iterator must not have been opened with 12552 ** the SQLITE_CHANGESETAPPLY_INVERT flag. In this case SQLITE_ERROR is also 12553 ** returned. 12554 */ 12555 SQLITE_API int sqlite3changegroup_add_change( 12556 sqlite3_changegroup*, 12557 sqlite3_changeset_iter* 12558 ); 12559 12560 12561 12562 /* 12563 ** CAPI3REF: Obtain A Composite Changeset From A Changegroup 12564 ** METHOD: sqlite3_changegroup 12565 ** 12566 ** Obtain a buffer containing a changeset (or patchset) representing the 12567 ** current contents of the changegroup. If the inputs to the changegroup 12568 ** were themselves changesets, the output is a changeset. Or, if the 12569 ** inputs were patchsets, the output is also a patchset. 12570 ** 12571 ** As with the output of the sqlite3session_changeset() and 12572 ** sqlite3session_patchset() functions, all changes related to a single 12573 ** table are grouped together in the output of this function. Tables appear 12574 ** in the same order as for the very first changeset added to the changegroup. 12575 ** If the second or subsequent changesets added to the changegroup contain 12576 ** changes for tables that do not appear in the first changeset, they are 12577 ** appended onto the end of the output changeset, again in the order in 12578 ** which they are first encountered. 12579 ** 12580 ** If an error occurs, an SQLite error code is returned and the output 12581 ** variables (*pnData) and (*ppData) are set to 0. Otherwise, SQLITE_OK 12582 ** is returned and the output variables are set to the size of and a 12583 ** pointer to the output buffer, respectively. In this case it is the 12584 ** responsibility of the caller to eventually free the buffer using a 12585 ** call to sqlite3_free(). 12586 */ 12587 SQLITE_API int sqlite3changegroup_output( 12588 sqlite3_changegroup*, 12589 int *pnData, /* OUT: Size of output buffer in bytes */ 12590 void **ppData /* OUT: Pointer to output buffer */ 12591 ); 12592 12593 /* 12594 ** CAPI3REF: Delete A Changegroup Object 12595 ** DESTRUCTOR: sqlite3_changegroup 12596 */ 12597 SQLITE_API void sqlite3changegroup_delete(sqlite3_changegroup*); 12598 12599 /* 12600 ** CAPI3REF: Apply A Changeset To A Database 12601 ** 12602 ** Apply a changeset or patchset to a database. These functions attempt to 12603 ** update the "main" database attached to handle db with the changes found in 12604 ** the changeset passed via the second and third arguments. 12605 ** 12606 ** All changes made by these functions are enclosed in a savepoint transaction. 12607 ** If any other error (aside from a constraint failure when attempting to 12608 ** write to the target database) occurs, then the savepoint transaction is 12609 ** rolled back, restoring the target database to its original state, and an 12610 ** SQLite error code returned. Additionally, starting with version 3.51.0, 12611 ** an error code and error message that may be accessed using the 12612 ** [sqlite3_errcode()] and [sqlite3_errmsg()] APIs are left in the database 12613 ** handle. 12614 ** 12615 ** The fourth argument (xFilter) passed to these functions is the "filter 12616 ** callback". This may be passed NULL, in which case all changes in the 12617 ** changeset are applied to the database. For sqlite3changeset_apply() and 12618 ** sqlite3_changeset_apply_v2(), if it is not NULL, then it is invoked once 12619 ** for each table affected by at least one change in the changeset. In this 12620 ** case the table name is passed as the second argument, and a copy of 12621 ** the context pointer passed as the sixth argument to apply() or apply_v2() 12622 ** as the first. If the "filter callback" returns zero, then no attempt is 12623 ** made to apply any changes to the table. Otherwise, if the return value is 12624 ** non-zero, all changes related to the table are attempted. 12625 ** 12626 ** For sqlite3_changeset_apply_v3(), the xFilter callback is invoked once 12627 ** per change. The second argument in this case is an sqlite3_changeset_iter 12628 ** that may be queried using the usual APIs for the details of the current 12629 ** change. If the "filter callback" returns zero in this case, then no attempt 12630 ** is made to apply the current change. If it returns non-zero, the change 12631 ** is applied. 12632 ** 12633 ** For each table that is not excluded by the filter callback, this function 12634 ** tests that the target database contains a compatible table. A table is 12635 ** considered compatible if all of the following are true: 12636 ** 12637 ** <ul> 12638 ** <li> The table has the same name as the name recorded in the 12639 ** changeset, and 12640 ** <li> The table has at least as many columns as recorded in the 12641 ** changeset, and 12642 ** <li> The table has primary key columns in the same position as 12643 ** recorded in the changeset. 12644 ** </ul> 12645 ** 12646 ** If there is no compatible table, it is not an error, but none of the 12647 ** changes associated with the table are applied. A warning message is issued 12648 ** via the sqlite3_log() mechanism with the error code SQLITE_SCHEMA. At most 12649 ** one such warning is issued for each table in the changeset. 12650 ** 12651 ** For each change for which there is a compatible table, an attempt is made 12652 ** to modify the table contents according to each UPDATE, INSERT or DELETE 12653 ** change that is not excluded by a filter callback. If a change cannot be 12654 ** applied cleanly, the conflict handler function passed as the fifth argument 12655 ** to sqlite3changeset_apply() may be invoked. A description of exactly when 12656 ** the conflict handler is invoked for each type of change is below. 12657 ** 12658 ** Unlike the xFilter argument, xConflict may not be passed NULL. The results 12659 ** of passing anything other than a valid function pointer as the xConflict 12660 ** argument are undefined. 12661 ** 12662 ** Each time the conflict handler function is invoked, it must return one 12663 ** of [SQLITE_CHANGESET_OMIT], [SQLITE_CHANGESET_ABORT] or 12664 ** [SQLITE_CHANGESET_REPLACE]. SQLITE_CHANGESET_REPLACE may only be returned 12665 ** if the second argument passed to the conflict handler is either 12666 ** SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If the conflict-handler 12667 ** returns an illegal value, any changes already made are rolled back and 12668 ** the call to sqlite3changeset_apply() returns SQLITE_MISUSE. Different 12669 ** actions are taken by sqlite3changeset_apply() depending on the value 12670 ** returned by each invocation of the conflict-handler function. Refer to 12671 ** the documentation for the three 12672 ** [SQLITE_CHANGESET_OMIT|available return values] for details. 12673 ** 12674 ** <dl> 12675 ** <dt>DELETE Changes<dd> 12676 ** For each DELETE change, the function checks if the target database 12677 ** contains a row with the same primary key value (or values) as the 12678 ** original row values stored in the changeset. If it does, and the values 12679 ** stored in all non-primary key columns also match the values stored in 12680 ** the changeset the row is deleted from the target database. 12681 ** 12682 ** If a row with matching primary key values is found, but one or more of 12683 ** the non-primary key fields contains a value different from the original 12684 ** row value stored in the changeset, the conflict-handler function is 12685 ** invoked with [SQLITE_CHANGESET_DATA] as the second argument. If the 12686 ** database table has more columns than are recorded in the changeset, 12687 ** only the values of those non-primary key fields are compared against 12688 ** the current database contents - any trailing database table columns 12689 ** are ignored. 12690 ** 12691 ** If no row with matching primary key values is found in the database, 12692 ** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND] 12693 ** passed as the second argument. 12694 ** 12695 ** If the DELETE operation is attempted, but SQLite returns SQLITE_CONSTRAINT 12696 ** (which can only happen if a foreign key constraint is violated), the 12697 ** conflict-handler function is invoked with [SQLITE_CHANGESET_CONSTRAINT] 12698 ** passed as the second argument. This includes the case where the DELETE 12699 ** operation is attempted because an earlier call to the conflict handler 12700 ** function returned [SQLITE_CHANGESET_REPLACE]. 12701 ** 12702 ** <dt>INSERT Changes<dd> 12703 ** For each INSERT change, an attempt is made to insert the new row into 12704 ** the database. If the changeset row contains fewer fields than the 12705 ** database table, the trailing fields are populated with their default 12706 ** values. 12707 ** 12708 ** If the attempt to insert the row fails because the database already 12709 ** contains a row with the same primary key values, the conflict handler 12710 ** function is invoked with the second argument set to 12711 ** [SQLITE_CHANGESET_CONFLICT]. 12712 ** 12713 ** If the attempt to insert the row fails because of some other constraint 12714 ** violation (e.g. NOT NULL or UNIQUE), the conflict handler function is 12715 ** invoked with the second argument set to [SQLITE_CHANGESET_CONSTRAINT]. 12716 ** This includes the case where the INSERT operation is re-attempted because 12717 ** an earlier call to the conflict handler function returned 12718 ** [SQLITE_CHANGESET_REPLACE]. 12719 ** 12720 ** <dt>UPDATE Changes<dd> 12721 ** For each UPDATE change, the function checks if the target database 12722 ** contains a row with the same primary key value (or values) as the 12723 ** original row values stored in the changeset. If it does, and the values 12724 ** stored in all modified non-primary key columns also match the values 12725 ** stored in the changeset the row is updated within the target database. 12726 ** 12727 ** If a row with matching primary key values is found, but one or more of 12728 ** the modified non-primary key fields contains a value different from an 12729 ** original row value stored in the changeset, the conflict-handler function 12730 ** is invoked with [SQLITE_CHANGESET_DATA] as the second argument. Since 12731 ** UPDATE changes only contain values for non-primary key fields that are 12732 ** to be modified, only those fields need to match the original values to 12733 ** avoid the SQLITE_CHANGESET_DATA conflict-handler callback. 12734 ** 12735 ** If no row with matching primary key values is found in the database, 12736 ** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND] 12737 ** passed as the second argument. 12738 ** 12739 ** If the UPDATE operation is attempted, but SQLite returns 12740 ** SQLITE_CONSTRAINT, the conflict-handler function is invoked with 12741 ** [SQLITE_CHANGESET_CONSTRAINT] passed as the second argument. 12742 ** This includes the case where the UPDATE operation is attempted after 12743 ** an earlier call to the conflict handler function returned 12744 ** [SQLITE_CHANGESET_REPLACE]. 12745 ** </dl> 12746 ** 12747 ** It is safe to execute SQL statements, including those that write to the 12748 ** table that the callback related to, from within the xConflict callback. 12749 ** This can be used to further customize the application's conflict 12750 ** resolution strategy. 12751 ** 12752 ** If the output parameters (ppRebase) and (pnRebase) are non-NULL and 12753 ** the input is a changeset (not a patchset), then sqlite3changeset_apply_v2() 12754 ** may set (*ppRebase) to point to a "rebase" that may be used with the 12755 ** sqlite3_rebaser APIs buffer before returning. In this case (*pnRebase) 12756 ** is set to the size of the buffer in bytes. It is the responsibility of the 12757 ** caller to eventually free any such buffer using sqlite3_free(). The buffer 12758 ** is only allocated and populated if one or more conflicts were encountered 12759 ** while applying the patchset. See comments surrounding the sqlite3_rebaser 12760 ** APIs for further details. 12761 ** 12762 ** The behavior of sqlite3changeset_apply_v2() and its streaming equivalent 12763 ** may be modified by passing a combination of 12764 ** [SQLITE_CHANGESETAPPLY_NOSAVEPOINT | supported flags] as the 9th parameter. 12765 ** 12766 ** Note that the sqlite3changeset_apply_v2() API is still <b>experimental</b> 12767 ** and therefore subject to change. 12768 */ 12769 SQLITE_API int sqlite3changeset_apply( 12770 sqlite3 *db, /* Apply change to "main" db of this handle */ 12771 int nChangeset, /* Size of changeset in bytes */ 12772 void *pChangeset, /* Changeset blob */ 12773 int(*xFilter)( 12774 void *pCtx, /* Copy of sixth arg to _apply() */ 12775 const char *zTab /* Table name */ 12776 ), 12777 int(*xConflict)( 12778 void *pCtx, /* Copy of sixth arg to _apply() */ 12779 int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ 12780 sqlite3_changeset_iter *p /* Handle describing change and conflict */ 12781 ), 12782 void *pCtx /* First argument passed to xConflict */ 12783 ); 12784 SQLITE_API int sqlite3changeset_apply_v2( 12785 sqlite3 *db, /* Apply change to "main" db of this handle */ 12786 int nChangeset, /* Size of changeset in bytes */ 12787 void *pChangeset, /* Changeset blob */ 12788 int(*xFilter)( 12789 void *pCtx, /* Copy of sixth arg to _apply() */ 12790 const char *zTab /* Table name */ 12791 ), 12792 int(*xConflict)( 12793 void *pCtx, /* Copy of sixth arg to _apply() */ 12794 int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ 12795 sqlite3_changeset_iter *p /* Handle describing change and conflict */ 12796 ), 12797 void *pCtx, /* First argument passed to xConflict */ 12798 void **ppRebase, int *pnRebase, /* OUT: Rebase data */ 12799 int flags /* SESSION_CHANGESETAPPLY_* flags */ 12800 ); 12801 SQLITE_API int sqlite3changeset_apply_v3( 12802 sqlite3 *db, /* Apply change to "main" db of this handle */ 12803 int nChangeset, /* Size of changeset in bytes */ 12804 void *pChangeset, /* Changeset blob */ 12805 int(*xFilter)( 12806 void *pCtx, /* Copy of sixth arg to _apply() */ 12807 sqlite3_changeset_iter *p /* Handle describing change */ 12808 ), 12809 int(*xConflict)( 12810 void *pCtx, /* Copy of sixth arg to _apply() */ 12811 int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ 12812 sqlite3_changeset_iter *p /* Handle describing change and conflict */ 12813 ), 12814 void *pCtx, /* First argument passed to xConflict */ 12815 void **ppRebase, int *pnRebase, /* OUT: Rebase data */ 12816 int flags /* SESSION_CHANGESETAPPLY_* flags */ 12817 ); 12818 12819 /* 12820 ** CAPI3REF: Flags for sqlite3changeset_apply_v2 12821 ** 12822 ** The following flags may passed via the 9th parameter to 12823 ** [sqlite3changeset_apply_v2] and [sqlite3changeset_apply_v2_strm]: 12824 ** 12825 ** <dl> 12826 ** <dt>SQLITE_CHANGESETAPPLY_NOSAVEPOINT <dd> 12827 ** Usually, the sessions module encloses all operations performed by 12828 ** a single call to apply_v2() or apply_v2_strm() in a [SAVEPOINT]. The 12829 ** SAVEPOINT is committed if the changeset or patchset is successfully 12830 ** applied, or rolled back if an error occurs. Specifying this flag 12831 ** causes the sessions module to omit this savepoint. In this case, if the 12832 ** caller has an open transaction or savepoint when apply_v2() is called, 12833 ** it may revert the partially applied changeset by rolling it back. 12834 ** 12835 ** <dt>SQLITE_CHANGESETAPPLY_INVERT <dd> 12836 ** Invert the changeset before applying it. This is equivalent to inverting 12837 ** a changeset using sqlite3changeset_invert() before applying it. It is 12838 ** an error to specify this flag with a patchset. 12839 ** 12840 ** <dt>SQLITE_CHANGESETAPPLY_IGNORENOOP <dd> 12841 ** Do not invoke the conflict handler callback for any changes that 12842 ** would not actually modify the database even if they were applied. 12843 ** Specifically, this means that the conflict handler is not invoked 12844 ** for: 12845 ** <ul> 12846 ** <li>a delete change if the row being deleted cannot be found, 12847 ** <li>an update change if the modified fields are already set to 12848 ** their new values in the conflicting row, or 12849 ** <li>an insert change if all fields of the conflicting row match 12850 ** the row being inserted. 12851 ** </ul> 12852 ** 12853 ** <dt>SQLITE_CHANGESETAPPLY_FKNOACTION <dd> 12854 ** If this flag it set, then all foreign key constraints in the target 12855 ** database behave as if they were declared with "ON UPDATE NO ACTION ON 12856 ** DELETE NO ACTION", even if they are actually CASCADE, RESTRICT, SET NULL 12857 ** or SET DEFAULT. 12858 ** 12859 ** <dt>SQLITE_CHANGESETAPPLY_NOUPDATELOOP <dd> 12860 ** Sometimes, a changeset contains two or more update statements such that 12861 ** although after applying all updates the database will contain no 12862 ** constraint violations, no single update can be applied before the others. 12863 ** The simplest example of this is a pair of UPDATEs that have "swapped" 12864 ** two column values with a UNIQUE constraint. 12865 ** <p> 12866 ** Usually, sqlite3changeset_apply() and similar functions work hard to try 12867 ** to find a way to apply such a changeset. However, if this flag is set, 12868 ** then all such updates are considered CONSTRAINT conflicts. 12869 */ 12870 #define SQLITE_CHANGESETAPPLY_NOSAVEPOINT 0x0001 12871 #define SQLITE_CHANGESETAPPLY_INVERT 0x0002 12872 #define SQLITE_CHANGESETAPPLY_IGNORENOOP 0x0004 12873 #define SQLITE_CHANGESETAPPLY_FKNOACTION 0x0008 12874 #define SQLITE_CHANGESETAPPLY_NOUPDATELOOP 0x0010 12875 12876 /* 12877 ** CAPI3REF: Constants Passed To The Conflict Handler 12878 ** 12879 ** Values that may be passed as the second argument to a conflict-handler. 12880 ** 12881 ** <dl> 12882 ** <dt>SQLITE_CHANGESET_DATA<dd> 12883 ** The conflict handler is invoked with CHANGESET_DATA as the second argument 12884 ** when processing a DELETE or UPDATE change if a row with the required 12885 ** PRIMARY KEY fields is present in the database, but one or more other 12886 ** (non primary-key) fields modified by the update do not contain the 12887 ** expected "before" values. 12888 ** 12889 ** The conflicting row, in this case, is the database row with the matching 12890 ** primary key. 12891 ** 12892 ** <dt>SQLITE_CHANGESET_NOTFOUND<dd> 12893 ** The conflict handler is invoked with CHANGESET_NOTFOUND as the second 12894 ** argument when processing a DELETE or UPDATE change if a row with the 12895 ** required PRIMARY KEY fields is not present in the database. 12896 ** 12897 ** There is no conflicting row in this case. The results of invoking the 12898 ** sqlite3changeset_conflict() API are undefined. 12899 ** 12900 ** <dt>SQLITE_CHANGESET_CONFLICT<dd> 12901 ** CHANGESET_CONFLICT is passed as the second argument to the conflict 12902 ** handler while processing an INSERT change if the operation would result 12903 ** in duplicate primary key values. 12904 ** 12905 ** The conflicting row in this case is the database row with the matching 12906 ** primary key. 12907 ** 12908 ** <dt>SQLITE_CHANGESET_FOREIGN_KEY<dd> 12909 ** If foreign key handling is enabled, and applying a changeset leaves the 12910 ** database in a state containing foreign key violations, the conflict 12911 ** handler is invoked with CHANGESET_FOREIGN_KEY as the second argument 12912 ** exactly once before the changeset is committed. If the conflict handler 12913 ** returns CHANGESET_OMIT, the changes, including those that caused the 12914 ** foreign key constraint violation, are committed. Or, if it returns 12915 ** CHANGESET_ABORT, the changeset is rolled back. 12916 ** 12917 ** No current or conflicting row information is provided. The only function 12918 ** it is possible to call on the supplied sqlite3_changeset_iter handle 12919 ** is sqlite3changeset_fk_conflicts(). 12920 ** 12921 ** <dt>SQLITE_CHANGESET_CONSTRAINT<dd> 12922 ** If any other constraint violation occurs while applying a change (i.e. 12923 ** a UNIQUE, CHECK or NOT NULL constraint), the conflict handler is 12924 ** invoked with CHANGESET_CONSTRAINT as the second argument. 12925 ** 12926 ** There is no conflicting row in this case. The results of invoking the 12927 ** sqlite3changeset_conflict() API are undefined. 12928 ** 12929 ** </dl> 12930 */ 12931 #define SQLITE_CHANGESET_DATA 1 12932 #define SQLITE_CHANGESET_NOTFOUND 2 12933 #define SQLITE_CHANGESET_CONFLICT 3 12934 #define SQLITE_CHANGESET_CONSTRAINT 4 12935 #define SQLITE_CHANGESET_FOREIGN_KEY 5 12936 12937 /* 12938 ** CAPI3REF: Constants Returned By The Conflict Handler 12939 ** 12940 ** A conflict handler callback must return one of the following three values. 12941 ** 12942 ** <dl> 12943 ** <dt>SQLITE_CHANGESET_OMIT<dd> 12944 ** If a conflict handler returns this value no special action is taken. The 12945 ** change that caused the conflict is not applied. The session module 12946 ** continues to the next change in the changeset. 12947 ** 12948 ** <dt>SQLITE_CHANGESET_REPLACE<dd> 12949 ** This value may only be returned if the second argument to the conflict 12950 ** handler was SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If this 12951 ** is not the case, any changes applied so far are rolled back and the 12952 ** call to sqlite3changeset_apply() returns SQLITE_MISUSE. 12953 ** 12954 ** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_DATA conflict 12955 ** handler, then the conflicting row is either updated or deleted, depending 12956 ** on the type of change. 12957 ** 12958 ** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_CONFLICT conflict 12959 ** handler, then the conflicting row is removed from the database and a 12960 ** second attempt to apply the change is made. If this second attempt fails, 12961 ** the original row is restored to the database before continuing. 12962 ** 12963 ** <dt>SQLITE_CHANGESET_ABORT<dd> 12964 ** If this value is returned, any changes applied so far are rolled back 12965 ** and the call to sqlite3changeset_apply() returns SQLITE_ABORT. 12966 ** </dl> 12967 */ 12968 #define SQLITE_CHANGESET_OMIT 0 12969 #define SQLITE_CHANGESET_REPLACE 1 12970 #define SQLITE_CHANGESET_ABORT 2 12971 12972 /* 12973 ** CAPI3REF: Rebasing changesets 12974 ** EXPERIMENTAL 12975 ** 12976 ** Suppose there is a site hosting a database in state S0. And that 12977 ** modifications are made that move that database to state S1 and a 12978 ** changeset recorded (the "local" changeset). Then, a changeset based 12979 ** on S0 is received from another site (the "remote" changeset) and 12980 ** applied to the database. The database is then in state 12981 ** (S1+"remote"), where the exact state depends on any conflict 12982 ** resolution decisions (OMIT or REPLACE) made while applying "remote". 12983 ** Rebasing a changeset is to update it to take those conflict 12984 ** resolution decisions into account, so that the same conflicts 12985 ** do not have to be resolved elsewhere in the network. 12986 ** 12987 ** For example, if both the local and remote changesets contain an 12988 ** INSERT of the same key on "CREATE TABLE t1(a PRIMARY KEY, b)": 12989 ** 12990 ** local: INSERT INTO t1 VALUES(1, 'v1'); 12991 ** remote: INSERT INTO t1 VALUES(1, 'v2'); 12992 ** 12993 ** and the conflict resolution is REPLACE, then the INSERT change is 12994 ** removed from the local changeset (it was overridden). Or, if the 12995 ** conflict resolution was "OMIT", then the local changeset is modified 12996 ** to instead contain: 12997 ** 12998 ** UPDATE t1 SET b = 'v2' WHERE a=1; 12999 ** 13000 ** Changes within the local changeset are rebased as follows: 13001 ** 13002 ** <dl> 13003 ** <dt>Local INSERT<dd> 13004 ** This may only conflict with a remote INSERT. If the conflict 13005 ** resolution was OMIT, then add an UPDATE change to the rebased 13006 ** changeset. Or, if the conflict resolution was REPLACE, add 13007 ** nothing to the rebased changeset. 13008 ** 13009 ** <dt>Local DELETE<dd> 13010 ** This may conflict with a remote UPDATE or DELETE. In both cases the 13011 ** only possible resolution is OMIT. If the remote operation was a 13012 ** DELETE, then add no change to the rebased changeset. If the remote 13013 ** operation was an UPDATE, then the old.* fields of change are updated 13014 ** to reflect the new.* values in the UPDATE. 13015 ** 13016 ** <dt>Local UPDATE<dd> 13017 ** This may conflict with a remote UPDATE or DELETE. If it conflicts 13018 ** with a DELETE, and the conflict resolution was OMIT, then the update 13019 ** is changed into an INSERT. Any undefined values in the new.* record 13020 ** from the update change are filled in using the old.* values from 13021 ** the conflicting DELETE. Or, if the conflict resolution was REPLACE, 13022 ** the UPDATE change is simply omitted from the rebased changeset. 13023 ** 13024 ** If conflict is with a remote UPDATE and the resolution is OMIT, then 13025 ** the old.* values are rebased using the new.* values in the remote 13026 ** change. Or, if the resolution is REPLACE, then the change is copied 13027 ** into the rebased changeset with updates to columns also updated by 13028 ** the conflicting remote UPDATE removed. If this means no columns would 13029 ** be updated, the change is omitted. 13030 ** </dl> 13031 ** 13032 ** A local change may be rebased against multiple remote changes 13033 ** simultaneously. If a single key is modified by multiple remote 13034 ** changesets, they are combined as follows before the local changeset 13035 ** is rebased: 13036 ** 13037 ** <ul> 13038 ** <li> If there has been one or more REPLACE resolutions on a 13039 ** key, it is rebased according to a REPLACE. 13040 ** 13041 ** <li> If there have been no REPLACE resolutions on a key, then 13042 ** the local changeset is rebased according to the most recent 13043 ** of the OMIT resolutions. 13044 ** </ul> 13045 ** 13046 ** Note that conflict resolutions from multiple remote changesets are 13047 ** combined on a per-field basis, not per-row. This means that in the 13048 ** case of multiple remote UPDATE operations, some fields of a single 13049 ** local change may be rebased for REPLACE while others are rebased for 13050 ** OMIT. 13051 ** 13052 ** In order to rebase a local changeset, the remote changeset must first 13053 ** be applied to the local database using sqlite3changeset_apply_v2() and 13054 ** the buffer of rebase information captured. Then: 13055 ** 13056 ** <ol> 13057 ** <li> An sqlite3_rebaser object is created by calling 13058 ** sqlite3rebaser_create(). 13059 ** <li> The new object is configured with the rebase buffer obtained from 13060 ** sqlite3changeset_apply_v2() by calling sqlite3rebaser_configure(). 13061 ** If the local changeset is to be rebased against multiple remote 13062 ** changesets, then sqlite3rebaser_configure() should be called 13063 ** multiple times, in the same order that the multiple 13064 ** sqlite3changeset_apply_v2() calls were made. 13065 ** <li> Each local changeset is rebased by calling sqlite3rebaser_rebase(). 13066 ** <li> The sqlite3_rebaser object is deleted by calling 13067 ** sqlite3rebaser_delete(). 13068 ** </ol> 13069 */ 13070 typedef struct sqlite3_rebaser sqlite3_rebaser; 13071 13072 /* 13073 ** CAPI3REF: Create a changeset rebaser object. 13074 ** EXPERIMENTAL 13075 ** 13076 ** Allocate a new changeset rebaser object. If successful, set (*ppNew) to 13077 ** point to the new object and return SQLITE_OK. Otherwise, if an error 13078 ** occurs, return an SQLite error code (e.g. SQLITE_NOMEM) and set (*ppNew) 13079 ** to NULL. 13080 */ 13081 SQLITE_API int sqlite3rebaser_create(sqlite3_rebaser **ppNew); 13082 13083 /* 13084 ** CAPI3REF: Configure a changeset rebaser object. 13085 ** EXPERIMENTAL 13086 ** 13087 ** Configure the changeset rebaser object to rebase changesets according 13088 ** to the conflict resolutions described by buffer pRebase (size nRebase 13089 ** bytes), which must have been obtained from a previous call to 13090 ** sqlite3changeset_apply_v2(). 13091 */ 13092 SQLITE_API int sqlite3rebaser_configure( 13093 sqlite3_rebaser*, 13094 int nRebase, const void *pRebase 13095 ); 13096 13097 /* 13098 ** CAPI3REF: Rebase a changeset 13099 ** EXPERIMENTAL 13100 ** 13101 ** Argument pIn must point to a buffer containing a changeset nIn bytes 13102 ** in size. This function allocates and populates a buffer with a copy 13103 ** of the changeset rebased according to the configuration of the 13104 ** rebaser object passed as the first argument. If successful, (*ppOut) 13105 ** is set to point to the new buffer containing the rebased changeset and 13106 ** (*pnOut) to its size in bytes and SQLITE_OK returned. It is the 13107 ** responsibility of the caller to eventually free the new buffer using 13108 ** sqlite3_free(). Otherwise, if an error occurs, (*ppOut) and (*pnOut) 13109 ** are set to zero and an SQLite error code returned. 13110 */ 13111 SQLITE_API int sqlite3rebaser_rebase( 13112 sqlite3_rebaser*, 13113 int nIn, const void *pIn, 13114 int *pnOut, void **ppOut 13115 ); 13116 13117 /* 13118 ** CAPI3REF: Delete a changeset rebaser object. 13119 ** EXPERIMENTAL 13120 ** 13121 ** Delete the changeset rebaser object and all associated resources. There 13122 ** should be one call to this function for each successful invocation 13123 ** of sqlite3rebaser_create(). 13124 */ 13125 SQLITE_API void sqlite3rebaser_delete(sqlite3_rebaser *p); 13126 13127 /* 13128 ** CAPI3REF: Streaming Versions of API functions. 13129 ** 13130 ** The six streaming API xxx_strm() functions serve similar purposes to the 13131 ** corresponding non-streaming API functions: 13132 ** 13133 ** <table border=1 style="margin-left:8ex;margin-right:8ex"> 13134 ** <tr><th>Streaming function<th>Non-streaming equivalent</th> 13135 ** <tr><td>sqlite3changeset_apply_strm<td>[sqlite3changeset_apply] 13136 ** <tr><td>sqlite3changeset_apply_strm_v2<td>[sqlite3changeset_apply_v2] 13137 ** <tr><td>sqlite3changeset_concat_strm<td>[sqlite3changeset_concat] 13138 ** <tr><td>sqlite3changeset_invert_strm<td>[sqlite3changeset_invert] 13139 ** <tr><td>sqlite3changeset_start_strm<td>[sqlite3changeset_start] 13140 ** <tr><td>sqlite3session_changeset_strm<td>[sqlite3session_changeset] 13141 ** <tr><td>sqlite3session_patchset_strm<td>[sqlite3session_patchset] 13142 ** </table> 13143 ** 13144 ** Non-streaming functions that accept changesets (or patchsets) as input 13145 ** require that the entire changeset be stored in a single buffer in memory. 13146 ** Similarly, those that return a changeset or patchset do so by returning 13147 ** a pointer to a single large buffer allocated using sqlite3_malloc(). 13148 ** Normally this is convenient. However, if an application running in a 13149 ** low-memory environment is required to handle very large changesets, the 13150 ** large contiguous memory allocations required can become onerous. 13151 ** 13152 ** In order to avoid this problem, instead of a single large buffer, input 13153 ** is passed to a streaming API functions by way of a callback function that 13154 ** the sessions module invokes to incrementally request input data as it is 13155 ** required. In all cases, a pair of API function parameters such as 13156 ** 13157 ** <pre> 13158 ** int nChangeset, 13159 ** void *pChangeset, 13160 ** </pre> 13161 ** 13162 ** Is replaced by: 13163 ** 13164 ** <pre> 13165 ** int (*xInput)(void *pIn, void *pData, int *pnData), 13166 ** void *pIn, 13167 ** </pre> 13168 ** 13169 ** Each time the xInput callback is invoked by the sessions module, the first 13170 ** argument passed is a copy of the supplied pIn context pointer. The second 13171 ** argument, pData, points to a buffer (*pnData) bytes in size. Assuming no 13172 ** error occurs the xInput method should copy up to (*pnData) bytes of data 13173 ** into the buffer and set (*pnData) to the actual number of bytes copied 13174 ** before returning SQLITE_OK. If the input is completely exhausted, (*pnData) 13175 ** should be set to zero to indicate this. Or, if an error occurs, an SQLite 13176 ** error code should be returned. In all cases, if an xInput callback returns 13177 ** an error, all processing is abandoned and the streaming API function 13178 ** returns a copy of the error code to the caller. 13179 ** 13180 ** In the case of sqlite3changeset_start_strm(), the xInput callback may be 13181 ** invoked by the sessions module at any point during the lifetime of the 13182 ** iterator. If such an xInput callback returns an error, the iterator enters 13183 ** an error state, whereby all subsequent calls to iterator functions 13184 ** immediately fail with the same error code as returned by xInput. 13185 ** 13186 ** Similarly, streaming API functions that return changesets (or patchsets) 13187 ** return them in chunks by way of a callback function instead of via a 13188 ** pointer to a single large buffer. In this case, a pair of parameters such 13189 ** as: 13190 ** 13191 ** <pre> 13192 ** int *pnChangeset, 13193 ** void **ppChangeset, 13194 ** </pre> 13195 ** 13196 ** Is replaced by: 13197 ** 13198 ** <pre> 13199 ** int (*xOutput)(void *pOut, const void *pData, int nData), 13200 ** void *pOut 13201 ** </pre> 13202 ** 13203 ** The xOutput callback is invoked zero or more times to return data to 13204 ** the application. The first parameter passed to each call is a copy of the 13205 ** pOut pointer supplied by the application. The second parameter, pData, 13206 ** points to a buffer nData bytes in size containing the chunk of output 13207 ** data being returned. If the xOutput callback successfully processes the 13208 ** supplied data, it should return SQLITE_OK to indicate success. Otherwise, 13209 ** it should return some other SQLite error code. In this case processing 13210 ** is immediately abandoned and the streaming API function returns a copy 13211 ** of the xOutput error code to the application. 13212 ** 13213 ** The sessions module never invokes an xOutput callback with the third 13214 ** parameter set to a value less than or equal to zero. Other than this, 13215 ** no guarantees are made as to the size of the chunks of data returned. 13216 */ 13217 SQLITE_API int sqlite3changeset_apply_strm( 13218 sqlite3 *db, /* Apply change to "main" db of this handle */ 13219 int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */ 13220 void *pIn, /* First arg for xInput */ 13221 int(*xFilter)( 13222 void *pCtx, /* Copy of sixth arg to _apply() */ 13223 const char *zTab /* Table name */ 13224 ), 13225 int(*xConflict)( 13226 void *pCtx, /* Copy of sixth arg to _apply() */ 13227 int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ 13228 sqlite3_changeset_iter *p /* Handle describing change and conflict */ 13229 ), 13230 void *pCtx /* First argument passed to xConflict */ 13231 ); 13232 SQLITE_API int sqlite3changeset_apply_v2_strm( 13233 sqlite3 *db, /* Apply change to "main" db of this handle */ 13234 int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */ 13235 void *pIn, /* First arg for xInput */ 13236 int(*xFilter)( 13237 void *pCtx, /* Copy of sixth arg to _apply() */ 13238 const char *zTab /* Table name */ 13239 ), 13240 int(*xConflict)( 13241 void *pCtx, /* Copy of sixth arg to _apply() */ 13242 int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ 13243 sqlite3_changeset_iter *p /* Handle describing change and conflict */ 13244 ), 13245 void *pCtx, /* First argument passed to xConflict */ 13246 void **ppRebase, int *pnRebase, 13247 int flags 13248 ); 13249 SQLITE_API int sqlite3changeset_apply_v3_strm( 13250 sqlite3 *db, /* Apply change to "main" db of this handle */ 13251 int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */ 13252 void *pIn, /* First arg for xInput */ 13253 int(*xFilter)( 13254 void *pCtx, /* Copy of sixth arg to _apply() */ 13255 sqlite3_changeset_iter *p 13256 ), 13257 int(*xConflict)( 13258 void *pCtx, /* Copy of sixth arg to _apply() */ 13259 int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ 13260 sqlite3_changeset_iter *p /* Handle describing change and conflict */ 13261 ), 13262 void *pCtx, /* First argument passed to xConflict */ 13263 void **ppRebase, int *pnRebase, 13264 int flags 13265 ); 13266 SQLITE_API int sqlite3changeset_concat_strm( 13267 int (*xInputA)(void *pIn, void *pData, int *pnData), 13268 void *pInA, 13269 int (*xInputB)(void *pIn, void *pData, int *pnData), 13270 void *pInB, 13271 int (*xOutput)(void *pOut, const void *pData, int nData), 13272 void *pOut 13273 ); 13274 SQLITE_API int sqlite3changeset_invert_strm( 13275 int (*xInput)(void *pIn, void *pData, int *pnData), 13276 void *pIn, 13277 int (*xOutput)(void *pOut, const void *pData, int nData), 13278 void *pOut 13279 ); 13280 SQLITE_API int sqlite3changeset_start_strm( 13281 sqlite3_changeset_iter **pp, 13282 int (*xInput)(void *pIn, void *pData, int *pnData), 13283 void *pIn 13284 ); 13285 SQLITE_API int sqlite3changeset_start_v2_strm( 13286 sqlite3_changeset_iter **pp, 13287 int (*xInput)(void *pIn, void *pData, int *pnData), 13288 void *pIn, 13289 int flags 13290 ); 13291 SQLITE_API int sqlite3session_changeset_strm( 13292 sqlite3_session *pSession, 13293 int (*xOutput)(void *pOut, const void *pData, int nData), 13294 void *pOut 13295 ); 13296 SQLITE_API int sqlite3session_patchset_strm( 13297 sqlite3_session *pSession, 13298 int (*xOutput)(void *pOut, const void *pData, int nData), 13299 void *pOut 13300 ); 13301 SQLITE_API int sqlite3changegroup_add_strm(sqlite3_changegroup*, 13302 int (*xInput)(void *pIn, void *pData, int *pnData), 13303 void *pIn 13304 ); 13305 SQLITE_API int sqlite3changegroup_output_strm(sqlite3_changegroup*, 13306 int (*xOutput)(void *pOut, const void *pData, int nData), 13307 void *pOut 13308 ); 13309 SQLITE_API int sqlite3rebaser_rebase_strm( 13310 sqlite3_rebaser *pRebaser, 13311 int (*xInput)(void *pIn, void *pData, int *pnData), 13312 void *pIn, 13313 int (*xOutput)(void *pOut, const void *pData, int nData), 13314 void *pOut 13315 ); 13316 13317 /* 13318 ** CAPI3REF: Configure global parameters 13319 ** 13320 ** The sqlite3session_config() interface is used to make global configuration 13321 ** changes to the sessions module in order to tune it to the specific needs 13322 ** of the application. 13323 ** 13324 ** The sqlite3session_config() interface is not threadsafe. If it is invoked 13325 ** while any other thread is inside any other sessions method then the 13326 ** results are undefined. Furthermore, if it is invoked after any sessions 13327 ** related objects have been created, the results are also undefined. 13328 ** 13329 ** The first argument to the sqlite3session_config() function must be one 13330 ** of the SQLITE_SESSION_CONFIG_XXX constants defined below. The 13331 ** interpretation of the (void*) value passed as the second parameter and 13332 ** the effect of calling this function depends on the value of the first 13333 ** parameter. 13334 ** 13335 ** <dl> 13336 ** <dt>SQLITE_SESSION_CONFIG_STRMSIZE<dd> 13337 ** By default, the sessions module streaming interfaces attempt to input 13338 ** and output data in approximately 1 KiB chunks. This operand may be used 13339 ** to set and query the value of this configuration setting. The pointer 13340 ** passed as the second argument must point to a value of type (int). 13341 ** If this value is greater than 0, it is used as the new streaming data 13342 ** chunk size for both input and output. Before returning, the (int) value 13343 ** pointed to by pArg is set to the final value of the streaming interface 13344 ** chunk size. 13345 ** </dl> 13346 ** 13347 ** This function returns SQLITE_OK if successful, or an SQLite error code 13348 ** otherwise. 13349 */ 13350 SQLITE_API int sqlite3session_config(int op, void *pArg); 13351 13352 /* 13353 ** CAPI3REF: Values for sqlite3session_config(). 13354 */ 13355 #define SQLITE_SESSION_CONFIG_STRMSIZE 1 13356 13357 /* 13358 ** CAPI3REF: Configure a changegroup object 13359 ** 13360 ** Configure the changegroup object passed as the first argument. 13361 ** At present the only valid value for the second parameter is 13362 ** [SQLITE_CHANGEGROUP_CONFIG_PATCHSET]. 13363 */ 13364 SQLITE_API int sqlite3changegroup_config(sqlite3_changegroup*, int, void *pArg); 13365 13366 /* 13367 ** CAPI3REF: Options for sqlite3changegroup_config(). 13368 ** 13369 ** The following values may be passed as the 2nd parameter to 13370 ** sqlite3changegroup_config(). 13371 ** 13372 ** <dt>SQLITE_CHANGEGROUP_CONFIG_PATCHSET <dd> 13373 ** A changegroup object generates either a changeset or patchset. Usually, 13374 ** this is determined by whether the first call to sqlite3changegroup_add() 13375 ** is passed a changeset or a patchset. Or, if the first changes are added 13376 ** to the changegroup object using the sqlite3changegroup_change_xxx() 13377 ** APIs, then this option may be used to configure whether the changegroup 13378 ** object generates a changeset or patchset. 13379 ** 13380 ** When this option is invoked, parameter pArg must point to a value of 13381 ** type int. If the changegroup currently contains zero changes, and the 13382 ** value of the int variable is zero or greater than zero, then the 13383 ** changegroup is configured to generate a changeset or patchset, 13384 ** respectively. It is a no-op, not an error, if the changegroup is not 13385 ** configured because it has already started accumulating changes. 13386 ** 13387 ** Before returning, the int variable is set to 0 if the changegroup is 13388 ** configured to generate a changeset, or 1 if it is configured to generate 13389 ** a patchset. 13390 */ 13391 #define SQLITE_CHANGEGROUP_CONFIG_PATCHSET 1 13392 13393 13394 /* 13395 ** CAPI3REF: Begin adding a change to a changegroup 13396 ** 13397 ** This API is used, in concert with other sqlite3changegroup_change_xxx() 13398 ** APIs, to add changes to a changegroup object one at a time. To add a 13399 ** single change, the caller must: 13400 ** 13401 ** 1. Invoke sqlite3changegroup_change_begin() to indicate the type of 13402 ** change (INSERT, UPDATE or DELETE), the affected table and whether 13403 ** or not the change should be marked as indirect. 13404 ** 13405 ** 2. Invoke sqlite3changegroup_change_int64() or one of the other four 13406 ** value functions - _null(), _double(), _text() or _blob() - one or 13407 ** more times to specify old.* and new.* values for the change being 13408 ** constructed. 13409 ** 13410 ** 3. Invoke sqlite3changegroup_change_finish() to either finish adding 13411 ** the change to the group, or to discard the change altogether. 13412 ** 13413 ** The first argument to this function must be a pointer to the existing 13414 ** changegroup object that the change will be added to. The second argument 13415 ** must be SQLITE_INSERT, SQLITE_UPDATE or SQLITE_DELETE. The third is the 13416 ** name of the table that the change affects, and the fourth is a boolean 13417 ** flag specifying whether the change should be marked as "indirect" (if 13418 ** bIndirect is non-zero) or not indirect (if bIndirect is zero). 13419 ** 13420 ** Following a successful call to this function, this function may not be 13421 ** called again on the same changegroup object until after 13422 ** sqlite3changegroup_change_finish() has been called. Doing so is an 13423 ** SQLITE_MISUSE error. 13424 ** 13425 ** The changegroup object passed as the first argument must be already 13426 ** configured with schema data for the specified table. It may be configured 13427 ** either by calling sqlite3changegroup_schema() with a database that contains 13428 ** the table, or sqlite3changegroup_add() with a changeset that contains the 13429 ** table. If the changegroup object has not been configured with a schema for 13430 ** the specified table when this function is called, SQLITE_ERROR is returned. 13431 ** 13432 ** If successful, SQLITE_OK is returned. Otherwise, if an error occurs, an 13433 ** SQLite error code is returned. In this case, if argument pzErr is non-NULL, 13434 ** then (*pzErr) may be set to point to a buffer containing a utf-8 formated, 13435 ** nul-terminated, English language error message. It is the responsibility 13436 ** of the caller to eventually free this buffer using sqlite3_free(). 13437 */ 13438 SQLITE_API int sqlite3changegroup_change_begin( 13439 sqlite3_changegroup*, 13440 int eOp, 13441 const char *zTab, 13442 int bIndirect, 13443 char **pzErr 13444 ); 13445 13446 /* 13447 ** CAPI3REF: Add a 64-bit integer to a changegroup 13448 ** 13449 ** This function may only be called between a successful call to 13450 ** sqlite3changegroup_change_begin() and its matching 13451 ** sqlite3changegroup_change_finish() call. If it is called at any 13452 ** other time, it is an SQLITE_MISUSE error. Calling this function 13453 ** specifies a 64-bit integer value to be used in the change currently being 13454 ** added to the changegroup object passed as the first argument. 13455 ** 13456 ** The second parameter, bNew, specifies whether the value is to be part of 13457 ** the new.* (if bNew is non-zero) or old.* (if bNew is zero) record of 13458 ** the change under construction. If this does not match the type of change 13459 ** specified by the preceding call to sqlite3changegroup_change_begin() (i.e. 13460 ** an old.* value for an SQLITE_INSERT change, or a new.* value for an 13461 ** SQLITE_DELETE), then SQLITE_ERROR is returned. 13462 ** 13463 ** The third parameter specifies the column of the old.* or new.* record that 13464 ** the value will be a part of. If the specified table has an explicit primary 13465 ** key, then this is the index of the table column, numbered from 0 in the order 13466 ** specified within the CREATE TABLE statement. Or, if the table uses an 13467 ** implicit rowid key, then the column 0 is the rowid and the explicit columns 13468 ** are numbered starting from 1. If the iCol parameter is less than 0 or greater 13469 ** than the index of the last column in the table, SQLITE_RANGE is returned. 13470 ** 13471 ** The fourth parameter is the integer value to use as part of the old.* or 13472 ** new.* record. 13473 ** 13474 ** If this call is successful, SQLITE_OK is returned. Otherwise, if an 13475 ** error occurs, an SQLite error code is returned. 13476 */ 13477 SQLITE_API int sqlite3changegroup_change_int64( 13478 sqlite3_changegroup*, 13479 int bNew, 13480 int iCol, 13481 sqlite3_int64 iVal 13482 ); 13483 13484 /* 13485 ** CAPI3REF: Add a NULL to a changegroup 13486 ** 13487 ** This function is similar to sqlite3changegroup_change_int64(). Except that 13488 ** it configures the change currently under construction with a NULL value 13489 ** instead of a 64-bit integer. 13490 */ 13491 SQLITE_API int sqlite3changegroup_change_null(sqlite3_changegroup*, int, int); 13492 13493 /* 13494 ** CAPI3REF: Add an double to a changegroup 13495 ** 13496 ** This function is similar to sqlite3changegroup_change_int64(). Except that 13497 ** it configures the change currently being constructed with a real value 13498 ** instead of a 64-bit integer. 13499 */ 13500 SQLITE_API int sqlite3changegroup_change_double(sqlite3_changegroup*, int, int, double); 13501 13502 /* 13503 ** CAPI3REF: Add a text value to a changegroup 13504 ** 13505 ** This function is similar to sqlite3changegroup_change_int64(). It configures 13506 ** the currently accumulated change with a text value instead of a 64-bit 13507 ** integer. Parameter pVal points to a buffer containing the text encoded using 13508 ** utf-8. Parameter nVal may either be the size of the text value in bytes, or 13509 ** else a negative value, in which case the buffer pVal points to is assumed to 13510 ** be nul-terminated. 13511 */ 13512 SQLITE_API int sqlite3changegroup_change_text( 13513 sqlite3_changegroup*, int, int, const char *pVal, int nVal 13514 ); 13515 13516 /* 13517 ** CAPI3REF: Add a blob to a changegroup 13518 ** 13519 ** This function is similar to sqlite3changegroup_change_int64(). It configures 13520 ** the currently accumulated change with a blob value instead of a 64-bit 13521 ** integer. Parameter pVal points to a buffer containing the blob. Parameter 13522 ** nVal is the size of the blob in bytes. 13523 */ 13524 SQLITE_API int sqlite3changegroup_change_blob( 13525 sqlite3_changegroup*, int, int, const void *pVal, int nVal 13526 ); 13527 13528 /* 13529 ** CAPI3REF: Finish adding one-at-at-time changes to a changegroup 13530 ** 13531 ** This function may only be called following a successful call to 13532 ** sqlite3changegroup_change_begin(). Otherwise, it is an SQLITE_MISUSE error. 13533 ** 13534 ** If parameter bDiscard is non-zero, then the current change is simply 13535 ** discarded. In this case this function is always successful and SQLITE_OK 13536 ** returned. 13537 ** 13538 ** If parameter bDiscard is zero, then an attempt is made to add the current 13539 ** change to the changegroup. Assuming the changegroup is configured to 13540 ** produce a changeset (not a patchset), this requires that: 13541 ** 13542 ** * If the change is an INSERT or DELETE, then a value must be specified 13543 ** for all columns of the new.* or old.* record, respectively. 13544 ** 13545 ** * If the change is an UPDATE record, then values must be provided for 13546 ** the PRIMARY KEY columns of the old.* record, but must not be provided 13547 ** for PRIMARY KEY columns of the new.* record. 13548 ** 13549 ** * If the change is an UPDATE record, then for each non-PRIMARY KEY 13550 ** column in the old.* record for which a value has been provided, a 13551 ** value must also be provided for the same column in the new.* record. 13552 ** Similarly, for each non-PK column in the old.* record for which 13553 ** a value is not provided, a value must not be provided for the same 13554 ** column in the new.* record. 13555 ** 13556 ** * All values specified for PRIMARY KEY columns must be non-NULL. 13557 ** 13558 ** Otherwise, it is an error. 13559 ** 13560 ** If the changegroup already contains a change for the same row (identified 13561 ** by PRIMARY KEY columns), then the current change is combined with the 13562 ** existing change in the same way as for sqlite3changegroup_add(). 13563 ** 13564 ** For a patchset, all of the above rules apply except that it doesn't matter 13565 ** whether or not values are provided for the non-PK old.* record columns 13566 ** for an UPDATE or DELETE change. This means that code used to produce 13567 ** a changeset using the sqlite3changegroup_change_xxx() APIs may also 13568 ** be used to produce patchsets. 13569 ** 13570 ** If the call is successful, SQLITE_OK is returned. Otherwise, if an error 13571 ** occurs, an SQLite error code is returned. If an error is returned and 13572 ** parameter pzErr is not NULL, then (*pzErr) may be set to point to a buffer 13573 ** containing a nul-terminated, utf-8 encoded, English language error message. 13574 ** It is the responsibility of the caller to eventually free any such error 13575 ** message buffer using sqlite3_free(). 13576 */ 13577 SQLITE_API int sqlite3changegroup_change_finish( 13578 sqlite3_changegroup*, 13579 int bDiscard, 13580 char **pzErr 13581 ); 13582 13583 /* 13584 ** Make sure we can call this stuff from C++. 13585 */ 13586 #ifdef __cplusplus 13587 } 13588 #endif 13589 13590 #endif /* !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) */ 13591 13592 /******** End of sqlite3session.h *********/ 13593 /******** Begin file fts5.h *********/ 13594 /* 13595 ** 2014 May 31 13596 ** 13597 ** The author disclaims copyright to this source code. In place of 13598 ** a legal notice, here is a blessing: 13599 ** 13600 ** May you do good and not evil. 13601 ** May you find forgiveness for yourself and forgive others. 13602 ** May you share freely, never taking more than you give. 13603 ** 13604 ****************************************************************************** 13605 ** 13606 ** Interfaces to extend FTS5. Using the interfaces defined in this file, 13607 ** FTS5 may be extended with: 13608 ** 13609 ** * custom tokenizers, and 13610 ** * custom auxiliary functions. 13611 */ 13612 13613 13614 #ifndef _FTS5_H 13615 #define _FTS5_H 13616 13617 13618 #ifdef __cplusplus 13619 extern "C" { 13620 #endif 13621 13622 /************************************************************************* 13623 ** CUSTOM AUXILIARY FUNCTIONS 13624 ** 13625 ** Virtual table implementations may overload SQL functions by implementing 13626 ** the sqlite3_module.xFindFunction() method. 13627 */ 13628 13629 typedef struct Fts5ExtensionApi Fts5ExtensionApi; 13630 typedef struct Fts5Context Fts5Context; 13631 typedef struct Fts5PhraseIter Fts5PhraseIter; 13632 13633 typedef void (*fts5_extension_function)( 13634 const Fts5ExtensionApi *pApi, /* API offered by current FTS version */ 13635 Fts5Context *pFts, /* First arg to pass to pApi functions */ 13636 sqlite3_context *pCtx, /* Context for returning result/error */ 13637 int nVal, /* Number of values in apVal[] array */ 13638 sqlite3_value **apVal /* Array of trailing arguments */ 13639 ); 13640 13641 struct Fts5PhraseIter { 13642 const unsigned char *a; 13643 const unsigned char *b; 13644 }; 13645 13646 /* 13647 ** EXTENSION API FUNCTIONS 13648 ** 13649 ** xUserData(pFts): 13650 ** Return a copy of the pUserData pointer passed to the xCreateFunction() 13651 ** API when the extension function was registered. 13652 ** 13653 ** xColumnTotalSize(pFts, iCol, pnToken): 13654 ** If parameter iCol is less than zero, set output variable *pnToken 13655 ** to the total number of tokens in the FTS5 table. Or, if iCol is 13656 ** non-negative but less than the number of columns in the table, return 13657 ** the total number of tokens in column iCol, considering all rows in 13658 ** the FTS5 table. 13659 ** 13660 ** If parameter iCol is greater than or equal to the number of columns 13661 ** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g. 13662 ** an OOM condition or IO error), an appropriate SQLite error code is 13663 ** returned. 13664 ** 13665 ** xColumnCount(pFts): 13666 ** Return the number of columns in the table. 13667 ** 13668 ** xColumnSize(pFts, iCol, pnToken): 13669 ** If parameter iCol is less than zero, set output variable *pnToken 13670 ** to the total number of tokens in the current row. Or, if iCol is 13671 ** non-negative but less than the number of columns in the table, set 13672 ** *pnToken to the number of tokens in column iCol of the current row. 13673 ** 13674 ** If parameter iCol is greater than or equal to the number of columns 13675 ** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g. 13676 ** an OOM condition or IO error), an appropriate SQLite error code is 13677 ** returned. 13678 ** 13679 ** This function may be quite inefficient if used with an FTS5 table 13680 ** created with the "columnsize=0" option. 13681 ** 13682 ** xColumnText: 13683 ** If parameter iCol is less than zero, or greater than or equal to the 13684 ** number of columns in the table, SQLITE_RANGE is returned. 13685 ** 13686 ** Otherwise, this function attempts to retrieve the text of column iCol of 13687 ** the current document. If successful, (*pz) is set to point to a buffer 13688 ** containing the text in utf-8 encoding, (*pn) is set to the size in bytes 13689 ** (not characters) of the buffer and SQLITE_OK is returned. Otherwise, 13690 ** if an error occurs, an SQLite error code is returned and the final values 13691 ** of (*pz) and (*pn) are undefined. 13692 ** 13693 ** xPhraseCount: 13694 ** Returns the number of phrases in the current query expression. 13695 ** 13696 ** xPhraseSize: 13697 ** If parameter iCol is less than zero, or greater than or equal to the 13698 ** number of phrases in the current query, as returned by xPhraseCount, 13699 ** 0 is returned. Otherwise, this function returns the number of tokens in 13700 ** phrase iPhrase of the query. Phrases are numbered starting from zero. 13701 ** 13702 ** xInstCount: 13703 ** Set *pnInst to the total number of occurrences of all phrases within 13704 ** the query within the current row. Return SQLITE_OK if successful, or 13705 ** an error code (i.e. SQLITE_NOMEM) if an error occurs. 13706 ** 13707 ** This API can be quite slow if used with an FTS5 table created with the 13708 ** "detail=none" or "detail=column" option. If the FTS5 table is created 13709 ** with either "detail=none" or "detail=column" and "content=" option 13710 ** (i.e. if it is a contentless table), then this API always returns 0. 13711 ** 13712 ** xInst: 13713 ** Query for the details of phrase match iIdx within the current row. 13714 ** Phrase matches are numbered starting from zero, so the iIdx argument 13715 ** should be greater than or equal to zero and smaller than the value 13716 ** output by xInstCount(). If iIdx is less than zero or greater than 13717 ** or equal to the value returned by xInstCount(), SQLITE_RANGE is returned. 13718 ** 13719 ** Otherwise, output parameter *piPhrase is set to the phrase number, *piCol 13720 ** to the column in which it occurs and *piOff the token offset of the 13721 ** first token of the phrase. SQLITE_OK is returned if successful, or an 13722 ** error code (i.e. SQLITE_NOMEM) if an error occurs. 13723 ** 13724 ** This API can be quite slow if used with an FTS5 table created with the 13725 ** "detail=none" or "detail=column" option. 13726 ** 13727 ** xRowid: 13728 ** Returns the rowid of the current row. 13729 ** 13730 ** xTokenize: 13731 ** Tokenize text using the tokenizer belonging to the FTS5 table. 13732 ** 13733 ** xQueryPhrase(pFts5, iPhrase, pUserData, xCallback): 13734 ** This API function is used to query the FTS table for phrase iPhrase 13735 ** of the current query. Specifically, a query equivalent to: 13736 ** 13737 ** ... FROM ftstable WHERE ftstable MATCH $p ORDER BY rowid 13738 ** 13739 ** with $p set to a phrase equivalent to the phrase iPhrase of the 13740 ** current query is executed. Any column filter that applies to 13741 ** phrase iPhrase of the current query is included in $p. For each 13742 ** row visited, the callback function passed as the fourth argument 13743 ** is invoked. The context and API objects passed to the callback 13744 ** function may be used to access the properties of each matched row. 13745 ** Invoking Api.xUserData() returns a copy of the pointer passed as 13746 ** the third argument to pUserData. 13747 ** 13748 ** If parameter iPhrase is less than zero, or greater than or equal to 13749 ** the number of phrases in the query, as returned by xPhraseCount(), 13750 ** this function returns SQLITE_RANGE. 13751 ** 13752 ** If the callback function returns any value other than SQLITE_OK, the 13753 ** query is abandoned and the xQueryPhrase function returns immediately. 13754 ** If the returned value is SQLITE_DONE, xQueryPhrase returns SQLITE_OK. 13755 ** Otherwise, the error code is propagated upwards. 13756 ** 13757 ** If the query runs to completion without incident, SQLITE_OK is returned. 13758 ** Or, if some error occurs before the query completes or is aborted by 13759 ** the callback, an SQLite error code is returned. 13760 ** 13761 ** 13762 ** xSetAuxdata(pFts5, pAux, xDelete) 13763 ** 13764 ** Save the pointer passed as the second argument as the extension function's 13765 ** "auxiliary data". The pointer may then be retrieved by the current or any 13766 ** future invocation of the same fts5 extension function made as part of 13767 ** the same MATCH query using the xGetAuxdata() API. 13768 ** 13769 ** Each extension function is allocated a single auxiliary data slot for 13770 ** each FTS query (MATCH expression). If the extension function is invoked 13771 ** more than once for a single FTS query, then all invocations share a 13772 ** single auxiliary data context. 13773 ** 13774 ** If there is already an auxiliary data pointer when this function is 13775 ** invoked, then it is replaced by the new pointer. If an xDelete callback 13776 ** was specified along with the original pointer, it is invoked at this 13777 ** point. 13778 ** 13779 ** The xDelete callback, if one is specified, is also invoked on the 13780 ** auxiliary data pointer after the FTS5 query has finished. 13781 ** 13782 ** If an error (e.g. an OOM condition) occurs within this function, 13783 ** the auxiliary data is set to NULL and an error code returned. If the 13784 ** xDelete parameter was not NULL, it is invoked on the auxiliary data 13785 ** pointer before returning. 13786 ** 13787 ** 13788 ** xGetAuxdata(pFts5, bClear) 13789 ** 13790 ** Returns the current auxiliary data pointer for the fts5 extension 13791 ** function. See the xSetAuxdata() method for details. 13792 ** 13793 ** If the bClear argument is non-zero, then the auxiliary data is cleared 13794 ** (set to NULL) before this function returns. In this case the xDelete, 13795 ** if any, is not invoked. 13796 ** 13797 ** 13798 ** xRowCount(pFts5, pnRow) 13799 ** 13800 ** This function is used to retrieve the total number of rows in the table. 13801 ** In other words, the same value that would be returned by: 13802 ** 13803 ** SELECT count(*) FROM ftstable; 13804 ** 13805 ** xPhraseFirst() 13806 ** This function is used, along with type Fts5PhraseIter and the xPhraseNext 13807 ** method, to iterate through all instances of a single query phrase within 13808 ** the current row. This is the same information as is accessible via the 13809 ** xInstCount/xInst APIs. While the xInstCount/xInst APIs are more convenient 13810 ** to use, this API may be faster under some circumstances. To iterate 13811 ** through instances of phrase iPhrase, use the following code: 13812 ** 13813 ** Fts5PhraseIter iter; 13814 ** int iCol, iOff; 13815 ** for(pApi->xPhraseFirst(pFts, iPhrase, &iter, &iCol, &iOff); 13816 ** iCol>=0; 13817 ** pApi->xPhraseNext(pFts, &iter, &iCol, &iOff) 13818 ** ){ 13819 ** // An instance of phrase iPhrase at offset iOff of column iCol 13820 ** } 13821 ** 13822 ** The Fts5PhraseIter structure is defined above. Applications should not 13823 ** modify this structure directly - it should only be used as shown above 13824 ** with the xPhraseFirst() and xPhraseNext() API methods (and by 13825 ** xPhraseFirstColumn() and xPhraseNextColumn() as illustrated below). 13826 ** 13827 ** This API can be quite slow if used with an FTS5 table created with the 13828 ** "detail=none" or "detail=column" option. If the FTS5 table is created 13829 ** with either "detail=none" or "detail=column" and "content=" option 13830 ** (i.e. if it is a contentless table), then this API always iterates 13831 ** through an empty set (all calls to xPhraseFirst() set iCol to -1). 13832 ** 13833 ** In all cases, matches are visited in (column ASC, offset ASC) order. 13834 ** i.e. all those in column 0, sorted by offset, followed by those in 13835 ** column 1, etc. 13836 ** 13837 ** xPhraseNext() 13838 ** See xPhraseFirst above. 13839 ** 13840 ** xPhraseFirstColumn() 13841 ** This function and xPhraseNextColumn() are similar to the xPhraseFirst() 13842 ** and xPhraseNext() APIs described above. The difference is that instead 13843 ** of iterating through all instances of a phrase in the current row, these 13844 ** APIs are used to iterate through the set of columns in the current row 13845 ** that contain one or more instances of a specified phrase. For example: 13846 ** 13847 ** Fts5PhraseIter iter; 13848 ** int iCol; 13849 ** for(pApi->xPhraseFirstColumn(pFts, iPhrase, &iter, &iCol); 13850 ** iCol>=0; 13851 ** pApi->xPhraseNextColumn(pFts, &iter, &iCol) 13852 ** ){ 13853 ** // Column iCol contains at least one instance of phrase iPhrase 13854 ** } 13855 ** 13856 ** This API can be quite slow if used with an FTS5 table created with the 13857 ** "detail=none" option. If the FTS5 table is created with either 13858 ** "detail=none" "content=" option (i.e. if it is a contentless table), 13859 ** then this API always iterates through an empty set (all calls to 13860 ** xPhraseFirstColumn() set iCol to -1). 13861 ** 13862 ** The information accessed using this API and its companion 13863 ** xPhraseFirstColumn() may also be obtained using xPhraseFirst/xPhraseNext 13864 ** (or xInst/xInstCount). The chief advantage of this API is that it is 13865 ** significantly more efficient than those alternatives when used with 13866 ** "detail=column" tables. 13867 ** 13868 ** xPhraseNextColumn() 13869 ** See xPhraseFirstColumn above. 13870 ** 13871 ** xQueryToken(pFts5, iPhrase, iToken, ppToken, pnToken) 13872 ** This is used to access token iToken of phrase iPhrase of the current 13873 ** query. Before returning, output parameter *ppToken is set to point 13874 ** to a buffer containing the requested token, and *pnToken to the 13875 ** size of this buffer in bytes. 13876 ** 13877 ** If iPhrase or iToken are less than zero, or if iPhrase is greater than 13878 ** or equal to the number of phrases in the query as reported by 13879 ** xPhraseCount(), or if iToken is equal to or greater than the number of 13880 ** tokens in the phrase, SQLITE_RANGE is returned and *ppToken and *pnToken 13881 are both zeroed. 13882 ** 13883 ** The output text is not a copy of the query text that specified the 13884 ** token. It is the output of the tokenizer module. For tokendata=1 13885 ** tables, this includes any embedded 0x00 and trailing data. 13886 ** 13887 ** xInstToken(pFts5, iIdx, iToken, ppToken, pnToken) 13888 ** This is used to access token iToken of phrase hit iIdx within the 13889 ** current row. If iIdx is less than zero or greater than or equal to the 13890 ** value returned by xInstCount(), SQLITE_RANGE is returned. Otherwise, 13891 ** output variable (*ppToken) is set to point to a buffer containing the 13892 ** matching document token, and (*pnToken) to the size of that buffer in 13893 ** bytes. 13894 ** 13895 ** The output text is not a copy of the document text that was tokenized. 13896 ** It is the output of the tokenizer module. For tokendata=1 tables, this 13897 ** includes any embedded 0x00 and trailing data. 13898 ** 13899 ** This API may be slow in some cases if the token identified by parameters 13900 ** iIdx and iToken matched a prefix token in the query. In most cases, the 13901 ** first call to this API for each prefix token in the query is forced 13902 ** to scan the portion of the full-text index that matches the prefix 13903 ** token to collect the extra data required by this API. If the prefix 13904 ** token matches a large number of token instances in the document set, 13905 ** this may be a performance problem. 13906 ** 13907 ** If the user knows in advance that a query may use this API for a 13908 ** prefix token, FTS5 may be configured to collect all required data as part 13909 ** of the initial querying of the full-text index, avoiding the second scan 13910 ** entirely. This also causes prefix queries that do not use this API to 13911 ** run more slowly and use more memory. FTS5 may be configured in this way 13912 ** either on a per-table basis using the [FTS5 insttoken | 'insttoken'] 13913 ** option, or on a per-query basis using the 13914 ** [fts5_insttoken | fts5_insttoken()] user function. 13915 ** 13916 ** This API can be quite slow if used with an FTS5 table created with the 13917 ** "detail=none" or "detail=column" option. 13918 ** 13919 ** xColumnLocale(pFts5, iIdx, pzLocale, pnLocale) 13920 ** If parameter iCol is less than zero, or greater than or equal to the 13921 ** number of columns in the table, SQLITE_RANGE is returned. 13922 ** 13923 ** Otherwise, this function attempts to retrieve the locale associated 13924 ** with column iCol of the current row. Usually, there is no associated 13925 ** locale, and output parameters (*pzLocale) and (*pnLocale) are set 13926 ** to NULL and 0, respectively. However, if the fts5_locale() function 13927 ** was used to associate a locale with the value when it was inserted 13928 ** into the fts5 table, then (*pzLocale) is set to point to a nul-terminated 13929 ** buffer containing the name of the locale in utf-8 encoding. (*pnLocale) 13930 ** is set to the size in bytes of the buffer, not including the 13931 ** nul-terminator. 13932 ** 13933 ** If successful, SQLITE_OK is returned. Or, if an error occurs, an 13934 ** SQLite error code is returned. The final value of the output parameters 13935 ** is undefined in this case. 13936 ** 13937 ** xTokenize_v2: 13938 ** Tokenize text using the tokenizer belonging to the FTS5 table. This 13939 ** API is the same as the xTokenize() API, except that it allows a tokenizer 13940 ** locale to be specified. 13941 */ 13942 struct Fts5ExtensionApi { 13943 int iVersion; /* Currently always set to 4 */ 13944 13945 void *(*xUserData)(Fts5Context*); 13946 13947 int (*xColumnCount)(Fts5Context*); 13948 int (*xRowCount)(Fts5Context*, sqlite3_int64 *pnRow); 13949 int (*xColumnTotalSize)(Fts5Context*, int iCol, sqlite3_int64 *pnToken); 13950 13951 int (*xTokenize)(Fts5Context*, 13952 const char *pText, int nText, /* Text to tokenize */ 13953 void *pCtx, /* Context passed to xToken() */ 13954 int (*xToken)(void*, int, const char*, int, int, int) /* Callback */ 13955 ); 13956 13957 int (*xPhraseCount)(Fts5Context*); 13958 int (*xPhraseSize)(Fts5Context*, int iPhrase); 13959 13960 int (*xInstCount)(Fts5Context*, int *pnInst); 13961 int (*xInst)(Fts5Context*, int iIdx, int *piPhrase, int *piCol, int *piOff); 13962 13963 sqlite3_int64 (*xRowid)(Fts5Context*); 13964 int (*xColumnText)(Fts5Context*, int iCol, const char **pz, int *pn); 13965 int (*xColumnSize)(Fts5Context*, int iCol, int *pnToken); 13966 13967 int (*xQueryPhrase)(Fts5Context*, int iPhrase, void *pUserData, 13968 int(*)(const Fts5ExtensionApi*,Fts5Context*,void*) 13969 ); 13970 int (*xSetAuxdata)(Fts5Context*, void *pAux, void(*xDelete)(void*)); 13971 void *(*xGetAuxdata)(Fts5Context*, int bClear); 13972 13973 int (*xPhraseFirst)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*, int*); 13974 void (*xPhraseNext)(Fts5Context*, Fts5PhraseIter*, int *piCol, int *piOff); 13975 13976 int (*xPhraseFirstColumn)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*); 13977 void (*xPhraseNextColumn)(Fts5Context*, Fts5PhraseIter*, int *piCol); 13978 13979 /* Below this point are iVersion>=3 only */ 13980 int (*xQueryToken)(Fts5Context*, 13981 int iPhrase, int iToken, 13982 const char **ppToken, int *pnToken 13983 ); 13984 int (*xInstToken)(Fts5Context*, int iIdx, int iToken, const char**, int*); 13985 13986 /* Below this point are iVersion>=4 only */ 13987 int (*xColumnLocale)(Fts5Context*, int iCol, const char **pz, int *pn); 13988 int (*xTokenize_v2)(Fts5Context*, 13989 const char *pText, int nText, /* Text to tokenize */ 13990 const char *pLocale, int nLocale, /* Locale to pass to tokenizer */ 13991 void *pCtx, /* Context passed to xToken() */ 13992 int (*xToken)(void*, int, const char*, int, int, int) /* Callback */ 13993 ); 13994 }; 13995 13996 /* 13997 ** CUSTOM AUXILIARY FUNCTIONS 13998 *************************************************************************/ 13999 14000 /************************************************************************* 14001 ** CUSTOM TOKENIZERS 14002 ** 14003 ** Applications may also register custom tokenizer types. A tokenizer 14004 ** is registered by providing fts5 with a populated instance of the 14005 ** following structure. All structure methods must be defined, setting 14006 ** any member of the fts5_tokenizer struct to NULL leads to undefined 14007 ** behaviour. The structure methods are expected to function as follows: 14008 ** 14009 ** xCreate: 14010 ** This function is used to allocate and initialize a tokenizer instance. 14011 ** A tokenizer instance is required to actually tokenize text. 14012 ** 14013 ** The first argument passed to this function is a copy of the (void*) 14014 ** pointer provided by the application when the fts5_tokenizer_v2 object 14015 ** was registered with FTS5 (the third argument to xCreateTokenizer()). 14016 ** The second and third arguments are an array of nul-terminated strings 14017 ** containing the tokenizer arguments, if any, specified following the 14018 ** tokenizer name as part of the CREATE VIRTUAL TABLE statement used 14019 ** to create the FTS5 table. 14020 ** 14021 ** The final argument is an output variable. If successful, (*ppOut) 14022 ** should be set to point to the new tokenizer handle and SQLITE_OK 14023 ** returned. If an error occurs, some value other than SQLITE_OK should 14024 ** be returned. In this case, fts5 assumes that the final value of *ppOut 14025 ** is undefined. 14026 ** 14027 ** xDelete: 14028 ** This function is invoked to delete a tokenizer handle previously 14029 ** allocated using xCreate(). Fts5 guarantees that this function will 14030 ** be invoked exactly once for each successful call to xCreate(). 14031 ** 14032 ** xTokenize: 14033 ** This function is expected to tokenize the nText byte string indicated 14034 ** by argument pText. pText may or may not be nul-terminated. The first 14035 ** argument passed to this function is a pointer to an Fts5Tokenizer object 14036 ** returned by an earlier call to xCreate(). 14037 ** 14038 ** The third argument indicates the reason that FTS5 is requesting 14039 ** tokenization of the supplied text. This is always one of the following 14040 ** four values: 14041 ** 14042 ** <ul><li> <b>FTS5_TOKENIZE_DOCUMENT</b> - A document is being inserted into 14043 ** or removed from the FTS table. The tokenizer is being invoked to 14044 ** determine the set of tokens to add to (or delete from) the 14045 ** FTS index. 14046 ** 14047 ** <li> <b>FTS5_TOKENIZE_QUERY</b> - A MATCH query is being executed 14048 ** against the FTS index. The tokenizer is being called to tokenize 14049 ** a bareword or quoted string specified as part of the query. 14050 ** 14051 ** <li> <b>(FTS5_TOKENIZE_QUERY | FTS5_TOKENIZE_PREFIX)</b> - Same as 14052 ** FTS5_TOKENIZE_QUERY, except that the bareword or quoted string is 14053 ** followed by a "*" character, indicating that the last token 14054 ** returned by the tokenizer will be treated as a token prefix. 14055 ** 14056 ** <li> <b>FTS5_TOKENIZE_AUX</b> - The tokenizer is being invoked to 14057 ** satisfy an fts5_api.xTokenize() request made by an auxiliary 14058 ** function. Or an fts5_api.xColumnSize() request made by the same 14059 ** on a columnsize=0 database. 14060 ** </ul> 14061 ** 14062 ** The sixth and seventh arguments passed to xTokenize() - pLocale and 14063 ** nLocale - are a pointer to a buffer containing the locale to use for 14064 ** tokenization (e.g. "en_US") and its size in bytes, respectively. The 14065 ** pLocale buffer is not nul-terminated. pLocale may be passed NULL (in 14066 ** which case nLocale is always 0) to indicate that the tokenizer should 14067 ** use its default locale. 14068 ** 14069 ** For each token in the input string, the supplied callback xToken() must 14070 ** be invoked. The first argument to it should be a copy of the pointer 14071 ** passed as the second argument to xTokenize(). The third and fourth 14072 ** arguments are a pointer to a buffer containing the token text, and the 14073 ** size of the token in bytes. The 4th and 5th arguments are the byte offsets 14074 ** of the first byte of and first byte immediately following the text from 14075 ** which the token is derived within the input. 14076 ** 14077 ** The second argument passed to the xToken() callback ("tflags") should 14078 ** normally be set to 0. The exception is if the tokenizer supports 14079 ** synonyms. In this case see the discussion below for details. 14080 ** 14081 ** FTS5 assumes the xToken() callback is invoked for each token in the 14082 ** order that they occur within the input text. 14083 ** 14084 ** If an xToken() callback returns any value other than SQLITE_OK, then 14085 ** the tokenization should be abandoned and the xTokenize() method should 14086 ** immediately return a copy of the xToken() return value. Or, if the 14087 ** input buffer is exhausted, xTokenize() should return SQLITE_OK. Finally, 14088 ** if an error occurs with the xTokenize() implementation itself, it 14089 ** may abandon the tokenization and return any error code other than 14090 ** SQLITE_OK or SQLITE_DONE. 14091 ** 14092 ** If the tokenizer is registered using an fts5_tokenizer_v2 object, 14093 ** then the xTokenize() method has two additional arguments - pLocale 14094 ** and nLocale. These specify the locale that the tokenizer should use 14095 ** for the current request. If pLocale and nLocale are both 0, then the 14096 ** tokenizer should use its default locale. Otherwise, pLocale points to 14097 ** an nLocale byte buffer containing the name of the locale to use as utf-8 14098 ** text. pLocale is not nul-terminated. 14099 ** 14100 ** FTS5_TOKENIZER 14101 ** 14102 ** There is also an fts5_tokenizer object. This is an older, deprecated, 14103 ** version of fts5_tokenizer_v2. It is similar except that: 14104 ** 14105 ** <ul> 14106 ** <li> There is no "iVersion" field, and 14107 ** <li> The xTokenize() method does not take a locale argument. 14108 ** </ul> 14109 ** 14110 ** Legacy fts5_tokenizer tokenizers must be registered using the 14111 ** legacy xCreateTokenizer() function, instead of xCreateTokenizer_v2(). 14112 ** 14113 ** Tokenizer implementations registered using either API may be retrieved 14114 ** using both xFindTokenizer() and xFindTokenizer_v2(). 14115 ** 14116 ** SYNONYM SUPPORT 14117 ** 14118 ** Custom tokenizers may also support synonyms. Consider a case in which a 14119 ** user wishes to query for a phrase such as "first place". Using the 14120 ** built-in tokenizers, the FTS5 query 'first + place' will match instances 14121 ** of "first place" within the document set, but not alternative forms 14122 ** such as "1st place". In some applications, it would be better to match 14123 ** all instances of "first place" or "1st place" regardless of which form 14124 ** the user specified in the MATCH query text. 14125 ** 14126 ** There are several ways to approach this in FTS5: 14127 ** 14128 ** <ol><li> By mapping all synonyms to a single token. In this case, using 14129 ** the above example, this means that the tokenizer returns the 14130 ** same token for inputs "first" and "1st". Say that token is in 14131 ** fact "first", so that when the user inserts the document "I won 14132 ** 1st place" entries are added to the index for tokens "i", "won", 14133 ** "first" and "place". If the user then queries for '1st + place', 14134 ** the tokenizer substitutes "first" for "1st" and the query works 14135 ** as expected. 14136 ** 14137 ** <li> By querying the index for all synonyms of each query term 14138 ** separately. In this case, when tokenizing query text, the 14139 ** tokenizer may provide multiple synonyms for a single term 14140 ** within the document. FTS5 then queries the index for each 14141 ** synonym individually. For example, faced with the query: 14142 ** 14143 ** <codeblock> 14144 ** ... MATCH 'first place'</codeblock> 14145 ** 14146 ** the tokenizer offers both "1st" and "first" as synonyms for the 14147 ** first token in the MATCH query and FTS5 effectively runs a query 14148 ** similar to: 14149 ** 14150 ** <codeblock> 14151 ** ... MATCH '(first OR 1st) place'</codeblock> 14152 ** 14153 ** except that, for the purposes of auxiliary functions, the query 14154 ** still appears to contain just two phrases - "(first OR 1st)" 14155 ** being treated as a single phrase. 14156 ** 14157 ** <li> By adding multiple synonyms for a single term to the FTS index. 14158 ** Using this method, when tokenizing document text, the tokenizer 14159 ** provides multiple synonyms for each token. So that when a 14160 ** document such as "I won first place" is tokenized, entries are 14161 ** added to the FTS index for "i", "won", "first", "1st" and 14162 ** "place". 14163 ** 14164 ** This way, even if the tokenizer does not provide synonyms 14165 ** when tokenizing query text (it should not - to do so would be 14166 ** inefficient), it doesn't matter if the user queries for 14167 ** 'first + place' or '1st + place', as there are entries in the 14168 ** FTS index corresponding to both forms of the first token. 14169 ** </ol> 14170 ** 14171 ** Whether it is parsing document or query text, any call to xToken that 14172 ** specifies a <i>tflags</i> argument with the FTS5_TOKEN_COLOCATED bit 14173 ** is considered to supply a synonym for the previous token. For example, 14174 ** when parsing the document "I won first place", a tokenizer that supports 14175 ** synonyms would call xToken() 5 times, as follows: 14176 ** 14177 ** <codeblock> 14178 ** xToken(pCtx, 0, "i", 1, 0, 1); 14179 ** xToken(pCtx, 0, "won", 3, 2, 5); 14180 ** xToken(pCtx, 0, "first", 5, 6, 11); 14181 ** xToken(pCtx, FTS5_TOKEN_COLOCATED, "1st", 3, 6, 11); 14182 ** xToken(pCtx, 0, "place", 5, 12, 17); 14183 **</codeblock> 14184 ** 14185 ** It is an error to specify the FTS5_TOKEN_COLOCATED flag the first time 14186 ** xToken() is called. Multiple synonyms may be specified for a single token 14187 ** by making multiple calls to xToken(FTS5_TOKEN_COLOCATED) in sequence. 14188 ** There is no limit to the number of synonyms that may be provided for a 14189 ** single token. 14190 ** 14191 ** In many cases, method (1) above is the best approach. It does not add 14192 ** extra data to the FTS index or require FTS5 to query for multiple terms, 14193 ** so it is efficient in terms of disk space and query speed. However, it 14194 ** does not support prefix queries very well. If, as suggested above, the 14195 ** token "first" is substituted for "1st" by the tokenizer, then the query: 14196 ** 14197 ** <codeblock> 14198 ** ... MATCH '1s*'</codeblock> 14199 ** 14200 ** will not match documents that contain the token "1st" (as the tokenizer 14201 ** will probably not map "1s" to any prefix of "first"). 14202 ** 14203 ** For full prefix support, method (3) may be preferred. In this case, 14204 ** because the index contains entries for both "first" and "1st", prefix 14205 ** queries such as 'fi*' or '1s*' will match correctly. However, because 14206 ** extra entries are added to the FTS index, this method uses more space 14207 ** within the database. 14208 ** 14209 ** Method (2) offers a midpoint between (1) and (3). Using this method, 14210 ** a query such as '1s*' will match documents that contain the literal 14211 ** token "1st", but not "first" (assuming the tokenizer is not able to 14212 ** provide synonyms for prefixes). However, a non-prefix query like '1st' 14213 ** will match against "1st" and "first". This method does not require 14214 ** extra disk space, as no extra entries are added to the FTS index. 14215 ** On the other hand, it may require more CPU cycles to run MATCH queries, 14216 ** as separate queries of the FTS index are required for each synonym. 14217 ** 14218 ** When using methods (2) or (3), it is important that the tokenizer only 14219 ** provide synonyms when tokenizing document text (method (3)) or query 14220 ** text (method (2)), not both. Doing so will not cause any errors, but is 14221 ** inefficient. 14222 */ 14223 typedef struct Fts5Tokenizer Fts5Tokenizer; 14224 typedef struct fts5_tokenizer_v2 fts5_tokenizer_v2; 14225 struct fts5_tokenizer_v2 { 14226 int iVersion; /* Currently always 2 */ 14227 14228 int (*xCreate)(void*, const char **azArg, int nArg, Fts5Tokenizer **ppOut); 14229 void (*xDelete)(Fts5Tokenizer*); 14230 int (*xTokenize)(Fts5Tokenizer*, 14231 void *pCtx, 14232 int flags, /* Mask of FTS5_TOKENIZE_* flags */ 14233 const char *pText, int nText, 14234 const char *pLocale, int nLocale, 14235 int (*xToken)( 14236 void *pCtx, /* Copy of 2nd argument to xTokenize() */ 14237 int tflags, /* Mask of FTS5_TOKEN_* flags */ 14238 const char *pToken, /* Pointer to buffer containing token */ 14239 int nToken, /* Size of token in bytes */ 14240 int iStart, /* Byte offset of token within input text */ 14241 int iEnd /* Byte offset of end of token within input text */ 14242 ) 14243 ); 14244 }; 14245 14246 /* 14247 ** New code should use the fts5_tokenizer_v2 type to define tokenizer 14248 ** implementations. The following type is included for legacy applications 14249 ** that still use it. 14250 */ 14251 typedef struct fts5_tokenizer fts5_tokenizer; 14252 struct fts5_tokenizer { 14253 int (*xCreate)(void*, const char **azArg, int nArg, Fts5Tokenizer **ppOut); 14254 void (*xDelete)(Fts5Tokenizer*); 14255 int (*xTokenize)(Fts5Tokenizer*, 14256 void *pCtx, 14257 int flags, /* Mask of FTS5_TOKENIZE_* flags */ 14258 const char *pText, int nText, 14259 int (*xToken)( 14260 void *pCtx, /* Copy of 2nd argument to xTokenize() */ 14261 int tflags, /* Mask of FTS5_TOKEN_* flags */ 14262 const char *pToken, /* Pointer to buffer containing token */ 14263 int nToken, /* Size of token in bytes */ 14264 int iStart, /* Byte offset of token within input text */ 14265 int iEnd /* Byte offset of end of token within input text */ 14266 ) 14267 ); 14268 }; 14269 14270 14271 /* Flags that may be passed as the third argument to xTokenize() */ 14272 #define FTS5_TOKENIZE_QUERY 0x0001 14273 #define FTS5_TOKENIZE_PREFIX 0x0002 14274 #define FTS5_TOKENIZE_DOCUMENT 0x0004 14275 #define FTS5_TOKENIZE_AUX 0x0008 14276 14277 /* Flags that may be passed by the tokenizer implementation back to FTS5 14278 ** as the third argument to the supplied xToken callback. */ 14279 #define FTS5_TOKEN_COLOCATED 0x0001 /* Same position as prev. token */ 14280 14281 /* 14282 ** END OF CUSTOM TOKENIZERS 14283 *************************************************************************/ 14284 14285 /************************************************************************* 14286 ** FTS5 EXTENSION REGISTRATION API 14287 */ 14288 typedef struct fts5_api fts5_api; 14289 struct fts5_api { 14290 int iVersion; /* Currently always set to 3 */ 14291 14292 /* Create a new tokenizer */ 14293 int (*xCreateTokenizer)( 14294 fts5_api *pApi, 14295 const char *zName, 14296 void *pUserData, 14297 fts5_tokenizer *pTokenizer, 14298 void (*xDestroy)(void*) 14299 ); 14300 14301 /* Find an existing tokenizer */ 14302 int (*xFindTokenizer)( 14303 fts5_api *pApi, 14304 const char *zName, 14305 void **ppUserData, 14306 fts5_tokenizer *pTokenizer 14307 ); 14308 14309 /* Create a new auxiliary function */ 14310 int (*xCreateFunction)( 14311 fts5_api *pApi, 14312 const char *zName, 14313 void *pUserData, 14314 fts5_extension_function xFunction, 14315 void (*xDestroy)(void*) 14316 ); 14317 14318 /* APIs below this point are only available if iVersion>=3 */ 14319 14320 /* Create a new tokenizer */ 14321 int (*xCreateTokenizer_v2)( 14322 fts5_api *pApi, 14323 const char *zName, 14324 void *pUserData, 14325 fts5_tokenizer_v2 *pTokenizer, 14326 void (*xDestroy)(void*) 14327 ); 14328 14329 /* Find an existing tokenizer */ 14330 int (*xFindTokenizer_v2)( 14331 fts5_api *pApi, 14332 const char *zName, 14333 void **ppUserData, 14334 fts5_tokenizer_v2 **ppTokenizer 14335 ); 14336 }; 14337 14338 /* 14339 ** END OF REGISTRATION API 14340 *************************************************************************/ 14341 14342 #ifdef __cplusplus 14343 } /* end of the 'extern "C"' block */ 14344 #endif 14345 14346 #endif /* _FTS5_H */ 14347 14348 /******** End of fts5.h *********/ 14349 #endif /* SQLITE3_H */ 14350