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://www.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 "3.46.1" 150 #define SQLITE_VERSION_NUMBER 3046001 151 #define SQLITE_SOURCE_ID "2024-08-13 09:16:08 c9c2ab54ba1f5f46360f1b4f35d849cd3f080e6fc2b6c60e91b16c63f69a1e33" 152 153 /* 154 ** CAPI3REF: Run-Time Library Version Numbers 155 ** KEYWORDS: sqlite3_version sqlite3_sourceid 156 ** 157 ** These interfaces provide the same information as the [SQLITE_VERSION], 158 ** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros 159 ** but are associated with the library instead of the header file. ^(Cautious 160 ** programmers might include assert() statements in their application to 161 ** verify that values returned by these interfaces match the macros in 162 ** the header, and thus ensure that the application is 163 ** compiled with matching library and header files. 164 ** 165 ** <blockquote><pre> 166 ** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER ); 167 ** assert( strncmp(sqlite3_sourceid(),SQLITE_SOURCE_ID,80)==0 ); 168 ** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 ); 169 ** </pre></blockquote>)^ 170 ** 171 ** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION] 172 ** macro. ^The sqlite3_libversion() function returns a pointer to the 173 ** to the sqlite3_version[] string constant. The sqlite3_libversion() 174 ** function is provided for use in DLLs since DLL users usually do not have 175 ** direct access to string constants within the DLL. ^The 176 ** sqlite3_libversion_number() function returns an integer equal to 177 ** [SQLITE_VERSION_NUMBER]. ^(The sqlite3_sourceid() function returns 178 ** a pointer to a string constant whose value is the same as the 179 ** [SQLITE_SOURCE_ID] C preprocessor macro. Except if SQLite is built 180 ** using an edited copy of [the amalgamation], then the last four characters 181 ** of the hash might be different from [SQLITE_SOURCE_ID].)^ 182 ** 183 ** See also: [sqlite_version()] and [sqlite_source_id()]. 184 */ 185 SQLITE_API SQLITE_EXTERN const char sqlite3_version[]; 186 SQLITE_API const char *sqlite3_libversion(void); 187 SQLITE_API const char *sqlite3_sourceid(void); 188 SQLITE_API int sqlite3_libversion_number(void); 189 190 /* 191 ** CAPI3REF: Run-Time Library Compilation Options Diagnostics 192 ** 193 ** ^The sqlite3_compileoption_used() function returns 0 or 1 194 ** indicating whether the specified option was defined at 195 ** compile time. ^The SQLITE_ prefix may be omitted from the 196 ** option name passed to sqlite3_compileoption_used(). 197 ** 198 ** ^The sqlite3_compileoption_get() function allows iterating 199 ** over the list of options that were defined at compile time by 200 ** returning the N-th compile time option string. ^If N is out of range, 201 ** sqlite3_compileoption_get() returns a NULL pointer. ^The SQLITE_ 202 ** prefix is omitted from any strings returned by 203 ** sqlite3_compileoption_get(). 204 ** 205 ** ^Support for the diagnostic functions sqlite3_compileoption_used() 206 ** and sqlite3_compileoption_get() may be omitted by specifying the 207 ** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time. 208 ** 209 ** See also: SQL functions [sqlite_compileoption_used()] and 210 ** [sqlite_compileoption_get()] and the [compile_options pragma]. 211 */ 212 #ifndef SQLITE_OMIT_COMPILEOPTION_DIAGS 213 SQLITE_API int sqlite3_compileoption_used(const char *zOptName); 214 SQLITE_API const char *sqlite3_compileoption_get(int N); 215 #else 216 # define sqlite3_compileoption_used(X) 0 217 # define sqlite3_compileoption_get(X) ((void*)0) 218 #endif 219 220 /* 221 ** CAPI3REF: Test To See If The Library Is Threadsafe 222 ** 223 ** ^The sqlite3_threadsafe() function returns zero if and only if 224 ** SQLite was compiled with mutexing code omitted due to the 225 ** [SQLITE_THREADSAFE] compile-time option being set to 0. 226 ** 227 ** SQLite can be compiled with or without mutexes. When 228 ** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes 229 ** are enabled and SQLite is threadsafe. When the 230 ** [SQLITE_THREADSAFE] macro is 0, 231 ** the mutexes are omitted. Without the mutexes, it is not safe 232 ** to use SQLite concurrently from more than one thread. 233 ** 234 ** Enabling mutexes incurs a measurable performance penalty. 235 ** So if speed is of utmost importance, it makes sense to disable 236 ** the mutexes. But for maximum safety, mutexes should be enabled. 237 ** ^The default behavior is for mutexes to be enabled. 238 ** 239 ** This interface can be used by an application to make sure that the 240 ** version of SQLite that it is linking against was compiled with 241 ** the desired setting of the [SQLITE_THREADSAFE] macro. 242 ** 243 ** This interface only reports on the compile-time mutex setting 244 ** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with 245 ** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but 246 ** can be fully or partially disabled using a call to [sqlite3_config()] 247 ** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD], 248 ** or [SQLITE_CONFIG_SERIALIZED]. ^(The return value of the 249 ** sqlite3_threadsafe() function shows only the compile-time setting of 250 ** thread safety, not any run-time changes to that setting made by 251 ** sqlite3_config(). In other words, the return value from sqlite3_threadsafe() 252 ** is unchanged by calls to sqlite3_config().)^ 253 ** 254 ** See the [threading mode] documentation for additional information. 255 */ 256 SQLITE_API int sqlite3_threadsafe(void); 257 258 /* 259 ** CAPI3REF: Database Connection Handle 260 ** KEYWORDS: {database connection} {database connections} 261 ** 262 ** Each open SQLite database is represented by a pointer to an instance of 263 ** the opaque structure named "sqlite3". It is useful to think of an sqlite3 264 ** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and 265 ** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()] 266 ** and [sqlite3_close_v2()] are its destructors. There are many other 267 ** interfaces (such as 268 ** [sqlite3_prepare_v2()], [sqlite3_create_function()], and 269 ** [sqlite3_busy_timeout()] to name but three) that are methods on an 270 ** sqlite3 object. 271 */ 272 typedef struct sqlite3 sqlite3; 273 274 /* 275 ** CAPI3REF: 64-Bit Integer Types 276 ** KEYWORDS: sqlite_int64 sqlite_uint64 277 ** 278 ** Because there is no cross-platform way to specify 64-bit integer types 279 ** SQLite includes typedefs for 64-bit signed and unsigned integers. 280 ** 281 ** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions. 282 ** The sqlite_int64 and sqlite_uint64 types are supported for backwards 283 ** compatibility only. 284 ** 285 ** ^The sqlite3_int64 and sqlite_int64 types can store integer values 286 ** between -9223372036854775808 and +9223372036854775807 inclusive. ^The 287 ** sqlite3_uint64 and sqlite_uint64 types can store integer values 288 ** between 0 and +18446744073709551615 inclusive. 289 */ 290 #ifdef SQLITE_INT64_TYPE 291 typedef SQLITE_INT64_TYPE sqlite_int64; 292 # ifdef SQLITE_UINT64_TYPE 293 typedef SQLITE_UINT64_TYPE sqlite_uint64; 294 # else 295 typedef unsigned SQLITE_INT64_TYPE sqlite_uint64; 296 # endif 297 #elif defined(_MSC_VER) || defined(__BORLANDC__) 298 typedef __int64 sqlite_int64; 299 typedef unsigned __int64 sqlite_uint64; 300 #else 301 typedef long long int sqlite_int64; 302 typedef unsigned long long int sqlite_uint64; 303 #endif 304 typedef sqlite_int64 sqlite3_int64; 305 typedef sqlite_uint64 sqlite3_uint64; 306 307 /* 308 ** If compiling for a processor that lacks floating point support, 309 ** substitute integer for floating-point. 310 */ 311 #ifdef SQLITE_OMIT_FLOATING_POINT 312 # define double sqlite3_int64 313 #endif 314 315 /* 316 ** CAPI3REF: Closing A Database Connection 317 ** DESTRUCTOR: sqlite3 318 ** 319 ** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors 320 ** for the [sqlite3] object. 321 ** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if 322 ** the [sqlite3] object is successfully destroyed and all associated 323 ** resources are deallocated. 324 ** 325 ** Ideally, applications should [sqlite3_finalize | finalize] all 326 ** [prepared statements], [sqlite3_blob_close | close] all [BLOB handles], and 327 ** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated 328 ** with the [sqlite3] object prior to attempting to close the object. 329 ** ^If the database connection is associated with unfinalized prepared 330 ** statements, BLOB handlers, and/or unfinished sqlite3_backup objects then 331 ** sqlite3_close() will leave the database connection open and return 332 ** [SQLITE_BUSY]. ^If sqlite3_close_v2() is called with unfinalized prepared 333 ** statements, unclosed BLOB handlers, and/or unfinished sqlite3_backups, 334 ** it returns [SQLITE_OK] regardless, but instead of deallocating the database 335 ** connection immediately, it marks the database connection as an unusable 336 ** "zombie" and makes arrangements to automatically deallocate the database 337 ** connection after all prepared statements are finalized, all BLOB handles 338 ** are closed, and all backups have finished. The sqlite3_close_v2() interface 339 ** is intended for use with host languages that are garbage collected, and 340 ** where the order in which destructors are called is arbitrary. 341 ** 342 ** ^If an [sqlite3] object is destroyed while a transaction is open, 343 ** the transaction is automatically rolled back. 344 ** 345 ** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)] 346 ** must be either a NULL 347 ** pointer or an [sqlite3] object pointer obtained 348 ** from [sqlite3_open()], [sqlite3_open16()], or 349 ** [sqlite3_open_v2()], and not previously closed. 350 ** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer 351 ** argument is a harmless no-op. 352 */ 353 SQLITE_API int sqlite3_close(sqlite3*); 354 SQLITE_API int sqlite3_close_v2(sqlite3*); 355 356 /* 357 ** The type for a callback function. 358 ** This is legacy and deprecated. It is included for historical 359 ** compatibility and is not documented. 360 */ 361 typedef int (*sqlite3_callback)(void*,int,char**, char**); 362 363 /* 364 ** CAPI3REF: One-Step Query Execution Interface 365 ** METHOD: sqlite3 366 ** 367 ** The sqlite3_exec() interface is a convenience wrapper around 368 ** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()], 369 ** that allows an application to run multiple statements of SQL 370 ** without having to use a lot of C code. 371 ** 372 ** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded, 373 ** semicolon-separate SQL statements passed into its 2nd argument, 374 ** in the context of the [database connection] passed in as its 1st 375 ** argument. ^If the callback function of the 3rd argument to 376 ** sqlite3_exec() is not NULL, then it is invoked for each result row 377 ** coming out of the evaluated SQL statements. ^The 4th argument to 378 ** sqlite3_exec() is relayed through to the 1st argument of each 379 ** callback invocation. ^If the callback pointer to sqlite3_exec() 380 ** is NULL, then no callback is ever invoked and result rows are 381 ** ignored. 382 ** 383 ** ^If an error occurs while evaluating the SQL statements passed into 384 ** sqlite3_exec(), then execution of the current statement stops and 385 ** subsequent statements are skipped. ^If the 5th parameter to sqlite3_exec() 386 ** is not NULL then any error message is written into memory obtained 387 ** from [sqlite3_malloc()] and passed back through the 5th parameter. 388 ** To avoid memory leaks, the application should invoke [sqlite3_free()] 389 ** on error message strings returned through the 5th parameter of 390 ** sqlite3_exec() after the error message string is no longer needed. 391 ** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors 392 ** occur, then sqlite3_exec() sets the pointer in its 5th parameter to 393 ** NULL before returning. 394 ** 395 ** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec() 396 ** routine returns SQLITE_ABORT without invoking the callback again and 397 ** without running any subsequent SQL statements. 398 ** 399 ** ^The 2nd argument to the sqlite3_exec() callback function is the 400 ** number of columns in the result. ^The 3rd argument to the sqlite3_exec() 401 ** callback is an array of pointers to strings obtained as if from 402 ** [sqlite3_column_text()], one for each column. ^If an element of a 403 ** result row is NULL then the corresponding string pointer for the 404 ** sqlite3_exec() callback is a NULL pointer. ^The 4th argument to the 405 ** sqlite3_exec() callback is an array of pointers to strings where each 406 ** entry represents the name of corresponding result column as obtained 407 ** from [sqlite3_column_name()]. 408 ** 409 ** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer 410 ** to an empty string, or a pointer that contains only whitespace and/or 411 ** SQL comments, then no SQL statements are evaluated and the database 412 ** is not changed. 413 ** 414 ** Restrictions: 415 ** 416 ** <ul> 417 ** <li> The application must ensure that the 1st parameter to sqlite3_exec() 418 ** is a valid and open [database connection]. 419 ** <li> The application must not close the [database connection] specified by 420 ** the 1st parameter to sqlite3_exec() while sqlite3_exec() is running. 421 ** <li> The application must not modify the SQL statement text passed into 422 ** the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running. 423 ** <li> The application must not dereference the arrays or string pointers 424 ** passed as the 3rd and 4th callback parameters after it returns. 425 ** </ul> 426 */ 427 SQLITE_API int sqlite3_exec( 428 sqlite3*, /* An open database */ 429 const char *sql, /* SQL to be evaluated */ 430 int (*callback)(void*,int,char**,char**), /* Callback function */ 431 void *, /* 1st argument to callback */ 432 char **errmsg /* Error msg written here */ 433 ); 434 435 /* 436 ** CAPI3REF: Result Codes 437 ** KEYWORDS: {result code definitions} 438 ** 439 ** Many SQLite functions return an integer result code from the set shown 440 ** here in order to indicate success or failure. 441 ** 442 ** New error codes may be added in future versions of SQLite. 443 ** 444 ** See also: [extended result code definitions] 445 */ 446 #define SQLITE_OK 0 /* Successful result */ 447 /* beginning-of-error-codes */ 448 #define SQLITE_ERROR 1 /* Generic error */ 449 #define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */ 450 #define SQLITE_PERM 3 /* Access permission denied */ 451 #define SQLITE_ABORT 4 /* Callback routine requested an abort */ 452 #define SQLITE_BUSY 5 /* The database file is locked */ 453 #define SQLITE_LOCKED 6 /* A table in the database is locked */ 454 #define SQLITE_NOMEM 7 /* A malloc() failed */ 455 #define SQLITE_READONLY 8 /* Attempt to write a readonly database */ 456 #define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/ 457 #define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */ 458 #define SQLITE_CORRUPT 11 /* The database disk image is malformed */ 459 #define SQLITE_NOTFOUND 12 /* Unknown opcode in sqlite3_file_control() */ 460 #define SQLITE_FULL 13 /* Insertion failed because database is full */ 461 #define SQLITE_CANTOPEN 14 /* Unable to open the database file */ 462 #define SQLITE_PROTOCOL 15 /* Database lock protocol error */ 463 #define SQLITE_EMPTY 16 /* Internal use only */ 464 #define SQLITE_SCHEMA 17 /* The database schema changed */ 465 #define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */ 466 #define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */ 467 #define SQLITE_MISMATCH 20 /* Data type mismatch */ 468 #define SQLITE_MISUSE 21 /* Library used incorrectly */ 469 #define SQLITE_NOLFS 22 /* Uses OS features not supported on host */ 470 #define SQLITE_AUTH 23 /* Authorization denied */ 471 #define SQLITE_FORMAT 24 /* Not used */ 472 #define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */ 473 #define SQLITE_NOTADB 26 /* File opened that is not a database file */ 474 #define SQLITE_NOTICE 27 /* Notifications from sqlite3_log() */ 475 #define SQLITE_WARNING 28 /* Warnings from sqlite3_log() */ 476 #define SQLITE_ROW 100 /* sqlite3_step() has another row ready */ 477 #define SQLITE_DONE 101 /* sqlite3_step() has finished executing */ 478 /* end-of-error-codes */ 479 480 /* 481 ** CAPI3REF: Extended Result Codes 482 ** KEYWORDS: {extended result code definitions} 483 ** 484 ** In its default configuration, SQLite API routines return one of 30 integer 485 ** [result codes]. However, experience has shown that many of 486 ** these result codes are too coarse-grained. They do not provide as 487 ** much information about problems as programmers might like. In an effort to 488 ** address this, newer versions of SQLite (version 3.3.8 [dateof:3.3.8] 489 ** and later) include 490 ** support for additional result codes that provide more detailed information 491 ** about errors. These [extended result codes] are enabled or disabled 492 ** on a per database connection basis using the 493 ** [sqlite3_extended_result_codes()] API. Or, the extended code for 494 ** the most recent error can be obtained using 495 ** [sqlite3_extended_errcode()]. 496 */ 497 #define SQLITE_ERROR_MISSING_COLLSEQ (SQLITE_ERROR | (1<<8)) 498 #define SQLITE_ERROR_RETRY (SQLITE_ERROR | (2<<8)) 499 #define SQLITE_ERROR_SNAPSHOT (SQLITE_ERROR | (3<<8)) 500 #define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8)) 501 #define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8)) 502 #define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8)) 503 #define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8)) 504 #define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8)) 505 #define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8)) 506 #define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8)) 507 #define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8)) 508 #define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8)) 509 #define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8)) 510 #define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8)) 511 #define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8)) 512 #define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8)) 513 #define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8)) 514 #define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8)) 515 #define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8)) 516 #define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8)) 517 #define SQLITE_IOERR_SHMOPEN (SQLITE_IOERR | (18<<8)) 518 #define SQLITE_IOERR_SHMSIZE (SQLITE_IOERR | (19<<8)) 519 #define SQLITE_IOERR_SHMLOCK (SQLITE_IOERR | (20<<8)) 520 #define SQLITE_IOERR_SHMMAP (SQLITE_IOERR | (21<<8)) 521 #define SQLITE_IOERR_SEEK (SQLITE_IOERR | (22<<8)) 522 #define SQLITE_IOERR_DELETE_NOENT (SQLITE_IOERR | (23<<8)) 523 #define SQLITE_IOERR_MMAP (SQLITE_IOERR | (24<<8)) 524 #define SQLITE_IOERR_GETTEMPPATH (SQLITE_IOERR | (25<<8)) 525 #define SQLITE_IOERR_CONVPATH (SQLITE_IOERR | (26<<8)) 526 #define SQLITE_IOERR_VNODE (SQLITE_IOERR | (27<<8)) 527 #define SQLITE_IOERR_AUTH (SQLITE_IOERR | (28<<8)) 528 #define SQLITE_IOERR_BEGIN_ATOMIC (SQLITE_IOERR | (29<<8)) 529 #define SQLITE_IOERR_COMMIT_ATOMIC (SQLITE_IOERR | (30<<8)) 530 #define SQLITE_IOERR_ROLLBACK_ATOMIC (SQLITE_IOERR | (31<<8)) 531 #define SQLITE_IOERR_DATA (SQLITE_IOERR | (32<<8)) 532 #define SQLITE_IOERR_CORRUPTFS (SQLITE_IOERR | (33<<8)) 533 #define SQLITE_IOERR_IN_PAGE (SQLITE_IOERR | (34<<8)) 534 #define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8)) 535 #define SQLITE_LOCKED_VTAB (SQLITE_LOCKED | (2<<8)) 536 #define SQLITE_BUSY_RECOVERY (SQLITE_BUSY | (1<<8)) 537 #define SQLITE_BUSY_SNAPSHOT (SQLITE_BUSY | (2<<8)) 538 #define SQLITE_BUSY_TIMEOUT (SQLITE_BUSY | (3<<8)) 539 #define SQLITE_CANTOPEN_NOTEMPDIR (SQLITE_CANTOPEN | (1<<8)) 540 #define SQLITE_CANTOPEN_ISDIR (SQLITE_CANTOPEN | (2<<8)) 541 #define SQLITE_CANTOPEN_FULLPATH (SQLITE_CANTOPEN | (3<<8)) 542 #define SQLITE_CANTOPEN_CONVPATH (SQLITE_CANTOPEN | (4<<8)) 543 #define SQLITE_CANTOPEN_DIRTYWAL (SQLITE_CANTOPEN | (5<<8)) /* Not Used */ 544 #define SQLITE_CANTOPEN_SYMLINK (SQLITE_CANTOPEN | (6<<8)) 545 #define SQLITE_CORRUPT_VTAB (SQLITE_CORRUPT | (1<<8)) 546 #define SQLITE_CORRUPT_SEQUENCE (SQLITE_CORRUPT | (2<<8)) 547 #define SQLITE_CORRUPT_INDEX (SQLITE_CORRUPT | (3<<8)) 548 #define SQLITE_READONLY_RECOVERY (SQLITE_READONLY | (1<<8)) 549 #define SQLITE_READONLY_CANTLOCK (SQLITE_READONLY | (2<<8)) 550 #define SQLITE_READONLY_ROLLBACK (SQLITE_READONLY | (3<<8)) 551 #define SQLITE_READONLY_DBMOVED (SQLITE_READONLY | (4<<8)) 552 #define SQLITE_READONLY_CANTINIT (SQLITE_READONLY | (5<<8)) 553 #define SQLITE_READONLY_DIRECTORY (SQLITE_READONLY | (6<<8)) 554 #define SQLITE_ABORT_ROLLBACK (SQLITE_ABORT | (2<<8)) 555 #define SQLITE_CONSTRAINT_CHECK (SQLITE_CONSTRAINT | (1<<8)) 556 #define SQLITE_CONSTRAINT_COMMITHOOK (SQLITE_CONSTRAINT | (2<<8)) 557 #define SQLITE_CONSTRAINT_FOREIGNKEY (SQLITE_CONSTRAINT | (3<<8)) 558 #define SQLITE_CONSTRAINT_FUNCTION (SQLITE_CONSTRAINT | (4<<8)) 559 #define SQLITE_CONSTRAINT_NOTNULL (SQLITE_CONSTRAINT | (5<<8)) 560 #define SQLITE_CONSTRAINT_PRIMARYKEY (SQLITE_CONSTRAINT | (6<<8)) 561 #define SQLITE_CONSTRAINT_TRIGGER (SQLITE_CONSTRAINT | (7<<8)) 562 #define SQLITE_CONSTRAINT_UNIQUE (SQLITE_CONSTRAINT | (8<<8)) 563 #define SQLITE_CONSTRAINT_VTAB (SQLITE_CONSTRAINT | (9<<8)) 564 #define SQLITE_CONSTRAINT_ROWID (SQLITE_CONSTRAINT |(10<<8)) 565 #define SQLITE_CONSTRAINT_PINNED (SQLITE_CONSTRAINT |(11<<8)) 566 #define SQLITE_CONSTRAINT_DATATYPE (SQLITE_CONSTRAINT |(12<<8)) 567 #define SQLITE_NOTICE_RECOVER_WAL (SQLITE_NOTICE | (1<<8)) 568 #define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8)) 569 #define SQLITE_NOTICE_RBU (SQLITE_NOTICE | (3<<8)) 570 #define SQLITE_WARNING_AUTOINDEX (SQLITE_WARNING | (1<<8)) 571 #define SQLITE_AUTH_USER (SQLITE_AUTH | (1<<8)) 572 #define SQLITE_OK_LOAD_PERMANENTLY (SQLITE_OK | (1<<8)) 573 #define SQLITE_OK_SYMLINK (SQLITE_OK | (2<<8)) /* internal use only */ 574 575 /* 576 ** CAPI3REF: Flags For File Open Operations 577 ** 578 ** These bit values are intended for use in the 579 ** 3rd parameter to the [sqlite3_open_v2()] interface and 580 ** in the 4th parameter to the [sqlite3_vfs.xOpen] method. 581 ** 582 ** Only those flags marked as "Ok for sqlite3_open_v2()" may be 583 ** used as the third argument to the [sqlite3_open_v2()] interface. 584 ** The other flags have historically been ignored by sqlite3_open_v2(), 585 ** though future versions of SQLite might change so that an error is 586 ** raised if any of the disallowed bits are passed into sqlite3_open_v2(). 587 ** Applications should not depend on the historical behavior. 588 ** 589 ** Note in particular that passing the SQLITE_OPEN_EXCLUSIVE flag into 590 ** [sqlite3_open_v2()] does *not* cause the underlying database file 591 ** to be opened using O_EXCL. Passing SQLITE_OPEN_EXCLUSIVE into 592 ** [sqlite3_open_v2()] has historically be a no-op and might become an 593 ** error in future versions of SQLite. 594 */ 595 #define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */ 596 #define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */ 597 #define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */ 598 #define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */ 599 #define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */ 600 #define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */ 601 #define SQLITE_OPEN_URI 0x00000040 /* Ok for sqlite3_open_v2() */ 602 #define SQLITE_OPEN_MEMORY 0x00000080 /* Ok for sqlite3_open_v2() */ 603 #define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */ 604 #define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */ 605 #define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */ 606 #define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */ 607 #define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */ 608 #define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */ 609 #define SQLITE_OPEN_SUPER_JOURNAL 0x00004000 /* VFS only */ 610 #define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */ 611 #define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */ 612 #define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */ 613 #define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */ 614 #define SQLITE_OPEN_WAL 0x00080000 /* VFS only */ 615 #define SQLITE_OPEN_NOFOLLOW 0x01000000 /* Ok for sqlite3_open_v2() */ 616 #define SQLITE_OPEN_EXRESCODE 0x02000000 /* Extended result codes */ 617 618 /* Reserved: 0x00F00000 */ 619 /* Legacy compatibility: */ 620 #define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */ 621 622 623 /* 624 ** CAPI3REF: Device Characteristics 625 ** 626 ** The xDeviceCharacteristics method of the [sqlite3_io_methods] 627 ** object returns an integer which is a vector of these 628 ** bit values expressing I/O characteristics of the mass storage 629 ** device that holds the file that the [sqlite3_io_methods] 630 ** refers to. 631 ** 632 ** The SQLITE_IOCAP_ATOMIC property means that all writes of 633 ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values 634 ** mean that writes of blocks that are nnn bytes in size and 635 ** are aligned to an address which is an integer multiple of 636 ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means 637 ** that when data is appended to a file, the data is appended 638 ** first then the size of the file is extended, never the other 639 ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that 640 ** information is written to disk in the same order as calls 641 ** to xWrite(). The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that 642 ** after reboot following a crash or power loss, the only bytes in a 643 ** file that were written at the application level might have changed 644 ** and that adjacent bytes, even bytes within the same sector are 645 ** guaranteed to be unchanged. The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 646 ** flag indicates that a file cannot be deleted when open. The 647 ** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on 648 ** read-only media and cannot be changed even by processes with 649 ** elevated privileges. 650 ** 651 ** The SQLITE_IOCAP_BATCH_ATOMIC property means that the underlying 652 ** filesystem supports doing multiple write operations atomically when those 653 ** write operations are bracketed by [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] and 654 ** [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]. 655 */ 656 #define SQLITE_IOCAP_ATOMIC 0x00000001 657 #define SQLITE_IOCAP_ATOMIC512 0x00000002 658 #define SQLITE_IOCAP_ATOMIC1K 0x00000004 659 #define SQLITE_IOCAP_ATOMIC2K 0x00000008 660 #define SQLITE_IOCAP_ATOMIC4K 0x00000010 661 #define SQLITE_IOCAP_ATOMIC8K 0x00000020 662 #define SQLITE_IOCAP_ATOMIC16K 0x00000040 663 #define SQLITE_IOCAP_ATOMIC32K 0x00000080 664 #define SQLITE_IOCAP_ATOMIC64K 0x00000100 665 #define SQLITE_IOCAP_SAFE_APPEND 0x00000200 666 #define SQLITE_IOCAP_SEQUENTIAL 0x00000400 667 #define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 0x00000800 668 #define SQLITE_IOCAP_POWERSAFE_OVERWRITE 0x00001000 669 #define SQLITE_IOCAP_IMMUTABLE 0x00002000 670 #define SQLITE_IOCAP_BATCH_ATOMIC 0x00004000 671 672 /* 673 ** CAPI3REF: File Locking Levels 674 ** 675 ** SQLite uses one of these integer values as the second 676 ** argument to calls it makes to the xLock() and xUnlock() methods 677 ** of an [sqlite3_io_methods] object. These values are ordered from 678 ** lest restrictive to most restrictive. 679 ** 680 ** The argument to xLock() is always SHARED or higher. The argument to 681 ** xUnlock is either SHARED or NONE. 682 */ 683 #define SQLITE_LOCK_NONE 0 /* xUnlock() only */ 684 #define SQLITE_LOCK_SHARED 1 /* xLock() or xUnlock() */ 685 #define SQLITE_LOCK_RESERVED 2 /* xLock() only */ 686 #define SQLITE_LOCK_PENDING 3 /* xLock() only */ 687 #define SQLITE_LOCK_EXCLUSIVE 4 /* xLock() only */ 688 689 /* 690 ** CAPI3REF: Synchronization Type Flags 691 ** 692 ** When SQLite invokes the xSync() method of an 693 ** [sqlite3_io_methods] object it uses a combination of 694 ** these integer values as the second argument. 695 ** 696 ** When the SQLITE_SYNC_DATAONLY flag is used, it means that the 697 ** sync operation only needs to flush data to mass storage. Inode 698 ** information need not be flushed. If the lower four bits of the flag 699 ** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics. 700 ** If the lower four bits equal SQLITE_SYNC_FULL, that means 701 ** to use Mac OS X style fullsync instead of fsync(). 702 ** 703 ** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags 704 ** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL 705 ** settings. The [synchronous pragma] determines when calls to the 706 ** xSync VFS method occur and applies uniformly across all platforms. 707 ** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how 708 ** energetic or rigorous or forceful the sync operations are and 709 ** only make a difference on Mac OSX for the default SQLite code. 710 ** (Third-party VFS implementations might also make the distinction 711 ** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the 712 ** operating systems natively supported by SQLite, only Mac OSX 713 ** cares about the difference.) 714 */ 715 #define SQLITE_SYNC_NORMAL 0x00002 716 #define SQLITE_SYNC_FULL 0x00003 717 #define SQLITE_SYNC_DATAONLY 0x00010 718 719 /* 720 ** CAPI3REF: OS Interface Open File Handle 721 ** 722 ** An [sqlite3_file] object represents an open file in the 723 ** [sqlite3_vfs | OS interface layer]. Individual OS interface 724 ** implementations will 725 ** want to subclass this object by appending additional fields 726 ** for their own use. The pMethods entry is a pointer to an 727 ** [sqlite3_io_methods] object that defines methods for performing 728 ** I/O operations on the open file. 729 */ 730 typedef struct sqlite3_file sqlite3_file; 731 struct sqlite3_file { 732 const struct sqlite3_io_methods *pMethods; /* Methods for an open file */ 733 }; 734 735 /* 736 ** CAPI3REF: OS Interface File Virtual Methods Object 737 ** 738 ** Every file opened by the [sqlite3_vfs.xOpen] method populates an 739 ** [sqlite3_file] object (or, more commonly, a subclass of the 740 ** [sqlite3_file] object) with a pointer to an instance of this object. 741 ** This object defines the methods used to perform various operations 742 ** against the open file represented by the [sqlite3_file] object. 743 ** 744 ** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element 745 ** to a non-NULL pointer, then the sqlite3_io_methods.xClose method 746 ** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed. The 747 ** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen] 748 ** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element 749 ** to NULL. 750 ** 751 ** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or 752 ** [SQLITE_SYNC_FULL]. The first choice is the normal fsync(). 753 ** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY] 754 ** flag may be ORed in to indicate that only the data of the file 755 ** and not its inode needs to be synced. 756 ** 757 ** The integer values to xLock() and xUnlock() are one of 758 ** <ul> 759 ** <li> [SQLITE_LOCK_NONE], 760 ** <li> [SQLITE_LOCK_SHARED], 761 ** <li> [SQLITE_LOCK_RESERVED], 762 ** <li> [SQLITE_LOCK_PENDING], or 763 ** <li> [SQLITE_LOCK_EXCLUSIVE]. 764 ** </ul> 765 ** xLock() upgrades the database file lock. In other words, xLock() moves the 766 ** database file lock in the direction NONE toward EXCLUSIVE. The argument to 767 ** xLock() is always one of SHARED, RESERVED, PENDING, or EXCLUSIVE, never 768 ** SQLITE_LOCK_NONE. If the database file lock is already at or above the 769 ** requested lock, then the call to xLock() is a no-op. 770 ** xUnlock() downgrades the database file lock to either SHARED or NONE. 771 ** If the lock is already at or below the requested lock state, then the call 772 ** to xUnlock() is a no-op. 773 ** The xCheckReservedLock() method checks whether any database connection, 774 ** either in this process or in some other process, is holding a RESERVED, 775 ** PENDING, or EXCLUSIVE lock on the file. It returns true 776 ** if such a lock exists and false otherwise. 777 ** 778 ** The xFileControl() method is a generic interface that allows custom 779 ** VFS implementations to directly control an open file using the 780 ** [sqlite3_file_control()] interface. The second "op" argument is an 781 ** integer opcode. The third argument is a generic pointer intended to 782 ** point to a structure that may contain arguments or space in which to 783 ** write return values. Potential uses for xFileControl() might be 784 ** functions to enable blocking locks with timeouts, to change the 785 ** locking strategy (for example to use dot-file locks), to inquire 786 ** about the status of a lock, or to break stale locks. The SQLite 787 ** core reserves all opcodes less than 100 for its own use. 788 ** A [file control opcodes | list of opcodes] less than 100 is available. 789 ** Applications that define a custom xFileControl method should use opcodes 790 ** greater than 100 to avoid conflicts. VFS implementations should 791 ** return [SQLITE_NOTFOUND] for file control opcodes that they do not 792 ** recognize. 793 ** 794 ** The xSectorSize() method returns the sector size of the 795 ** device that underlies the file. The sector size is the 796 ** minimum write that can be performed without disturbing 797 ** other bytes in the file. The xDeviceCharacteristics() 798 ** method returns a bit vector describing behaviors of the 799 ** underlying device: 800 ** 801 ** <ul> 802 ** <li> [SQLITE_IOCAP_ATOMIC] 803 ** <li> [SQLITE_IOCAP_ATOMIC512] 804 ** <li> [SQLITE_IOCAP_ATOMIC1K] 805 ** <li> [SQLITE_IOCAP_ATOMIC2K] 806 ** <li> [SQLITE_IOCAP_ATOMIC4K] 807 ** <li> [SQLITE_IOCAP_ATOMIC8K] 808 ** <li> [SQLITE_IOCAP_ATOMIC16K] 809 ** <li> [SQLITE_IOCAP_ATOMIC32K] 810 ** <li> [SQLITE_IOCAP_ATOMIC64K] 811 ** <li> [SQLITE_IOCAP_SAFE_APPEND] 812 ** <li> [SQLITE_IOCAP_SEQUENTIAL] 813 ** <li> [SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN] 814 ** <li> [SQLITE_IOCAP_POWERSAFE_OVERWRITE] 815 ** <li> [SQLITE_IOCAP_IMMUTABLE] 816 ** <li> [SQLITE_IOCAP_BATCH_ATOMIC] 817 ** </ul> 818 ** 819 ** The SQLITE_IOCAP_ATOMIC property means that all writes of 820 ** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values 821 ** mean that writes of blocks that are nnn bytes in size and 822 ** are aligned to an address which is an integer multiple of 823 ** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means 824 ** that when data is appended to a file, the data is appended 825 ** first then the size of the file is extended, never the other 826 ** way around. The SQLITE_IOCAP_SEQUENTIAL property means that 827 ** information is written to disk in the same order as calls 828 ** to xWrite(). 829 ** 830 ** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill 831 ** in the unread portions of the buffer with zeros. A VFS that 832 ** fails to zero-fill short reads might seem to work. However, 833 ** failure to zero-fill short reads will eventually lead to 834 ** database corruption. 835 */ 836 typedef struct sqlite3_io_methods sqlite3_io_methods; 837 struct sqlite3_io_methods { 838 int iVersion; 839 int (*xClose)(sqlite3_file*); 840 int (*xRead)(sqlite3_file*, void*, int iAmt, sqlite3_int64 iOfst); 841 int (*xWrite)(sqlite3_file*, const void*, int iAmt, sqlite3_int64 iOfst); 842 int (*xTruncate)(sqlite3_file*, sqlite3_int64 size); 843 int (*xSync)(sqlite3_file*, int flags); 844 int (*xFileSize)(sqlite3_file*, sqlite3_int64 *pSize); 845 int (*xLock)(sqlite3_file*, int); 846 int (*xUnlock)(sqlite3_file*, int); 847 int (*xCheckReservedLock)(sqlite3_file*, int *pResOut); 848 int (*xFileControl)(sqlite3_file*, int op, void *pArg); 849 int (*xSectorSize)(sqlite3_file*); 850 int (*xDeviceCharacteristics)(sqlite3_file*); 851 /* Methods above are valid for version 1 */ 852 int (*xShmMap)(sqlite3_file*, int iPg, int pgsz, int, void volatile**); 853 int (*xShmLock)(sqlite3_file*, int offset, int n, int flags); 854 void (*xShmBarrier)(sqlite3_file*); 855 int (*xShmUnmap)(sqlite3_file*, int deleteFlag); 856 /* Methods above are valid for version 2 */ 857 int (*xFetch)(sqlite3_file*, sqlite3_int64 iOfst, int iAmt, void **pp); 858 int (*xUnfetch)(sqlite3_file*, sqlite3_int64 iOfst, void *p); 859 /* Methods above are valid for version 3 */ 860 /* Additional methods may be added in future releases */ 861 }; 862 863 /* 864 ** CAPI3REF: Standard File Control Opcodes 865 ** KEYWORDS: {file control opcodes} {file control opcode} 866 ** 867 ** These integer constants are opcodes for the xFileControl method 868 ** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()] 869 ** interface. 870 ** 871 ** <ul> 872 ** <li>[[SQLITE_FCNTL_LOCKSTATE]] 873 ** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This 874 ** opcode causes the xFileControl method to write the current state of 875 ** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED], 876 ** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE]) 877 ** into an integer that the pArg argument points to. 878 ** This capability is only available if SQLite is compiled with [SQLITE_DEBUG]. 879 ** 880 ** <li>[[SQLITE_FCNTL_SIZE_HINT]] 881 ** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS 882 ** layer a hint of how large the database file will grow to be during the 883 ** current transaction. This hint is not guaranteed to be accurate but it 884 ** is often close. The underlying VFS might choose to preallocate database 885 ** file space based on this hint in order to help writes to the database 886 ** file run faster. 887 ** 888 ** <li>[[SQLITE_FCNTL_SIZE_LIMIT]] 889 ** The [SQLITE_FCNTL_SIZE_LIMIT] opcode is used by in-memory VFS that 890 ** implements [sqlite3_deserialize()] to set an upper bound on the size 891 ** of the in-memory database. The argument is a pointer to a [sqlite3_int64]. 892 ** If the integer pointed to is negative, then it is filled in with the 893 ** current limit. Otherwise the limit is set to the larger of the value 894 ** of the integer pointed to and the current database size. The integer 895 ** pointed to is set to the new limit. 896 ** 897 ** <li>[[SQLITE_FCNTL_CHUNK_SIZE]] 898 ** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS 899 ** extends and truncates the database file in chunks of a size specified 900 ** by the user. The fourth argument to [sqlite3_file_control()] should 901 ** point to an integer (type int) containing the new chunk-size to use 902 ** for the nominated database. Allocating database file space in large 903 ** chunks (say 1MB at a time), may reduce file-system fragmentation and 904 ** improve performance on some systems. 905 ** 906 ** <li>[[SQLITE_FCNTL_FILE_POINTER]] 907 ** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer 908 ** to the [sqlite3_file] object associated with a particular database 909 ** connection. See also [SQLITE_FCNTL_JOURNAL_POINTER]. 910 ** 911 ** <li>[[SQLITE_FCNTL_JOURNAL_POINTER]] 912 ** The [SQLITE_FCNTL_JOURNAL_POINTER] opcode is used to obtain a pointer 913 ** to the [sqlite3_file] object associated with the journal file (either 914 ** the [rollback journal] or the [write-ahead log]) for a particular database 915 ** connection. See also [SQLITE_FCNTL_FILE_POINTER]. 916 ** 917 ** <li>[[SQLITE_FCNTL_SYNC_OMITTED]] 918 ** No longer in use. 919 ** 920 ** <li>[[SQLITE_FCNTL_SYNC]] 921 ** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and 922 ** sent to the VFS immediately before the xSync method is invoked on a 923 ** database file descriptor. Or, if the xSync method is not invoked 924 ** because the user has configured SQLite with 925 ** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place 926 ** of the xSync method. In most cases, the pointer argument passed with 927 ** this file-control is NULL. However, if the database file is being synced 928 ** as part of a multi-database commit, the argument points to a nul-terminated 929 ** string containing the transactions super-journal file name. VFSes that 930 ** do not need this signal should silently ignore this opcode. Applications 931 ** should not call [sqlite3_file_control()] with this opcode as doing so may 932 ** disrupt the operation of the specialized VFSes that do require it. 933 ** 934 ** <li>[[SQLITE_FCNTL_COMMIT_PHASETWO]] 935 ** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite 936 ** and sent to the VFS after a transaction has been committed immediately 937 ** but before the database is unlocked. VFSes that do not need this signal 938 ** should silently ignore this opcode. Applications should not call 939 ** [sqlite3_file_control()] with this opcode as doing so may disrupt the 940 ** operation of the specialized VFSes that do require it. 941 ** 942 ** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]] 943 ** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic 944 ** retry counts and intervals for certain disk I/O operations for the 945 ** windows [VFS] in order to provide robustness in the presence of 946 ** anti-virus programs. By default, the windows VFS will retry file read, 947 ** file write, and file delete operations up to 10 times, with a delay 948 ** of 25 milliseconds before the first retry and with the delay increasing 949 ** by an additional 25 milliseconds with each subsequent retry. This 950 ** opcode allows these two values (10 retries and 25 milliseconds of delay) 951 ** to be adjusted. The values are changed for all database connections 952 ** within the same process. The argument is a pointer to an array of two 953 ** integers where the first integer is the new retry count and the second 954 ** integer is the delay. If either integer is negative, then the setting 955 ** is not changed but instead the prior value of that setting is written 956 ** into the array entry, allowing the current retry settings to be 957 ** interrogated. The zDbName parameter is ignored. 958 ** 959 ** <li>[[SQLITE_FCNTL_PERSIST_WAL]] 960 ** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the 961 ** persistent [WAL | Write Ahead Log] setting. By default, the auxiliary 962 ** write ahead log ([WAL file]) and shared memory 963 ** files used for transaction control 964 ** are automatically deleted when the latest connection to the database 965 ** closes. Setting persistent WAL mode causes those files to persist after 966 ** close. Persisting the files is useful when other processes that do not 967 ** have write permission on the directory containing the database file want 968 ** to read the database file, as the WAL and shared memory files must exist 969 ** in order for the database to be readable. The fourth parameter to 970 ** [sqlite3_file_control()] for this opcode should be a pointer to an integer. 971 ** That integer is 0 to disable persistent WAL mode or 1 to enable persistent 972 ** WAL mode. If the integer is -1, then it is overwritten with the current 973 ** WAL persistence setting. 974 ** 975 ** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]] 976 ** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the 977 ** persistent "powersafe-overwrite" or "PSOW" setting. The PSOW setting 978 ** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the 979 ** xDeviceCharacteristics methods. The fourth parameter to 980 ** [sqlite3_file_control()] for this opcode should be a pointer to an integer. 981 ** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage 982 ** mode. If the integer is -1, then it is overwritten with the current 983 ** zero-damage mode setting. 984 ** 985 ** <li>[[SQLITE_FCNTL_OVERWRITE]] 986 ** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening 987 ** a write transaction to indicate that, unless it is rolled back for some 988 ** reason, the entire database file will be overwritten by the current 989 ** transaction. This is used by VACUUM operations. 990 ** 991 ** <li>[[SQLITE_FCNTL_VFSNAME]] 992 ** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of 993 ** all [VFSes] in the VFS stack. The names are of all VFS shims and the 994 ** final bottom-level VFS are written into memory obtained from 995 ** [sqlite3_malloc()] and the result is stored in the char* variable 996 ** that the fourth parameter of [sqlite3_file_control()] points to. 997 ** The caller is responsible for freeing the memory when done. As with 998 ** all file-control actions, there is no guarantee that this will actually 999 ** do anything. Callers should initialize the char* variable to a NULL 1000 ** pointer in case this file-control is not implemented. This file-control 1001 ** is intended for diagnostic use only. 1002 ** 1003 ** <li>[[SQLITE_FCNTL_VFS_POINTER]] 1004 ** ^The [SQLITE_FCNTL_VFS_POINTER] opcode finds a pointer to the top-level 1005 ** [VFSes] currently in use. ^(The argument X in 1006 ** sqlite3_file_control(db,SQLITE_FCNTL_VFS_POINTER,X) must be 1007 ** of type "[sqlite3_vfs] **". This opcodes will set *X 1008 ** to a pointer to the top-level VFS.)^ 1009 ** ^When there are multiple VFS shims in the stack, this opcode finds the 1010 ** upper-most shim only. 1011 ** 1012 ** <li>[[SQLITE_FCNTL_PRAGMA]] 1013 ** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA] 1014 ** file control is sent to the open [sqlite3_file] object corresponding 1015 ** to the database file to which the pragma statement refers. ^The argument 1016 ** to the [SQLITE_FCNTL_PRAGMA] file control is an array of 1017 ** pointers to strings (char**) in which the second element of the array 1018 ** is the name of the pragma and the third element is the argument to the 1019 ** pragma or NULL if the pragma has no argument. ^The handler for an 1020 ** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element 1021 ** of the char** argument point to a string obtained from [sqlite3_mprintf()] 1022 ** or the equivalent and that string will become the result of the pragma or 1023 ** the error message if the pragma fails. ^If the 1024 ** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal 1025 ** [PRAGMA] processing continues. ^If the [SQLITE_FCNTL_PRAGMA] 1026 ** file control returns [SQLITE_OK], then the parser assumes that the 1027 ** VFS has handled the PRAGMA itself and the parser generates a no-op 1028 ** prepared statement if result string is NULL, or that returns a copy 1029 ** of the result string if the string is non-NULL. 1030 ** ^If the [SQLITE_FCNTL_PRAGMA] file control returns 1031 ** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means 1032 ** that the VFS encountered an error while handling the [PRAGMA] and the 1033 ** compilation of the PRAGMA fails with an error. ^The [SQLITE_FCNTL_PRAGMA] 1034 ** file control occurs at the beginning of pragma statement analysis and so 1035 ** it is able to override built-in [PRAGMA] statements. 1036 ** 1037 ** <li>[[SQLITE_FCNTL_BUSYHANDLER]] 1038 ** ^The [SQLITE_FCNTL_BUSYHANDLER] 1039 ** file-control may be invoked by SQLite on the database file handle 1040 ** shortly after it is opened in order to provide a custom VFS with access 1041 ** to the connection's busy-handler callback. The argument is of type (void**) 1042 ** - an array of two (void *) values. The first (void *) actually points 1043 ** to a function of type (int (*)(void *)). In order to invoke the connection's 1044 ** busy-handler, this function should be invoked with the second (void *) in 1045 ** the array as the only argument. If it returns non-zero, then the operation 1046 ** should be retried. If it returns zero, the custom VFS should abandon the 1047 ** current operation. 1048 ** 1049 ** <li>[[SQLITE_FCNTL_TEMPFILENAME]] 1050 ** ^Applications can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control 1051 ** to have SQLite generate a 1052 ** temporary filename using the same algorithm that is followed to generate 1053 ** temporary filenames for TEMP tables and other internal uses. The 1054 ** argument should be a char** which will be filled with the filename 1055 ** written into memory obtained from [sqlite3_malloc()]. The caller should 1056 ** invoke [sqlite3_free()] on the result to avoid a memory leak. 1057 ** 1058 ** <li>[[SQLITE_FCNTL_MMAP_SIZE]] 1059 ** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the 1060 ** maximum number of bytes that will be used for memory-mapped I/O. 1061 ** The argument is a pointer to a value of type sqlite3_int64 that 1062 ** is an advisory maximum number of bytes in the file to memory map. The 1063 ** pointer is overwritten with the old value. The limit is not changed if 1064 ** the value originally pointed to is negative, and so the current limit 1065 ** can be queried by passing in a pointer to a negative number. This 1066 ** file-control is used internally to implement [PRAGMA mmap_size]. 1067 ** 1068 ** <li>[[SQLITE_FCNTL_TRACE]] 1069 ** The [SQLITE_FCNTL_TRACE] file control provides advisory information 1070 ** to the VFS about what the higher layers of the SQLite stack are doing. 1071 ** This file control is used by some VFS activity tracing [shims]. 1072 ** The argument is a zero-terminated string. Higher layers in the 1073 ** SQLite stack may generate instances of this file control if 1074 ** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled. 1075 ** 1076 ** <li>[[SQLITE_FCNTL_HAS_MOVED]] 1077 ** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a 1078 ** pointer to an integer and it writes a boolean into that integer depending 1079 ** on whether or not the file has been renamed, moved, or deleted since it 1080 ** was first opened. 1081 ** 1082 ** <li>[[SQLITE_FCNTL_WIN32_GET_HANDLE]] 1083 ** The [SQLITE_FCNTL_WIN32_GET_HANDLE] opcode can be used to obtain the 1084 ** underlying native file handle associated with a file handle. This file 1085 ** control interprets its argument as a pointer to a native file handle and 1086 ** writes the resulting value there. 1087 ** 1088 ** <li>[[SQLITE_FCNTL_WIN32_SET_HANDLE]] 1089 ** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging. This 1090 ** opcode causes the xFileControl method to swap the file handle with the one 1091 ** pointed to by the pArg argument. This capability is used during testing 1092 ** and only needs to be supported when SQLITE_TEST is defined. 1093 ** 1094 ** <li>[[SQLITE_FCNTL_WAL_BLOCK]] 1095 ** The [SQLITE_FCNTL_WAL_BLOCK] is a signal to the VFS layer that it might 1096 ** be advantageous to block on the next WAL lock if the lock is not immediately 1097 ** available. The WAL subsystem issues this signal during rare 1098 ** circumstances in order to fix a problem with priority inversion. 1099 ** Applications should <em>not</em> use this file-control. 1100 ** 1101 ** <li>[[SQLITE_FCNTL_ZIPVFS]] 1102 ** The [SQLITE_FCNTL_ZIPVFS] opcode is implemented by zipvfs only. All other 1103 ** VFS should return SQLITE_NOTFOUND for this opcode. 1104 ** 1105 ** <li>[[SQLITE_FCNTL_RBU]] 1106 ** The [SQLITE_FCNTL_RBU] opcode is implemented by the special VFS used by 1107 ** the RBU extension only. All other VFS should return SQLITE_NOTFOUND for 1108 ** this opcode. 1109 ** 1110 ** <li>[[SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]] 1111 ** If the [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] opcode returns SQLITE_OK, then 1112 ** the file descriptor is placed in "batch write mode", which 1113 ** means all subsequent write operations will be deferred and done 1114 ** atomically at the next [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]. Systems 1115 ** that do not support batch atomic writes will return SQLITE_NOTFOUND. 1116 ** ^Following a successful SQLITE_FCNTL_BEGIN_ATOMIC_WRITE and prior to 1117 ** the closing [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] or 1118 ** [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE], SQLite will make 1119 ** no VFS interface calls on the same [sqlite3_file] file descriptor 1120 ** except for calls to the xWrite method and the xFileControl method 1121 ** with [SQLITE_FCNTL_SIZE_HINT]. 1122 ** 1123 ** <li>[[SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]] 1124 ** The [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE] opcode causes all write 1125 ** operations since the previous successful call to 1126 ** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be performed atomically. 1127 ** This file control returns [SQLITE_OK] if and only if the writes were 1128 ** all performed successfully and have been committed to persistent storage. 1129 ** ^Regardless of whether or not it is successful, this file control takes 1130 ** the file descriptor out of batch write mode so that all subsequent 1131 ** write operations are independent. 1132 ** ^SQLite will never invoke SQLITE_FCNTL_COMMIT_ATOMIC_WRITE without 1133 ** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]. 1134 ** 1135 ** <li>[[SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE]] 1136 ** The [SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE] opcode causes all write 1137 ** operations since the previous successful call to 1138 ** [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] to be rolled back. 1139 ** ^This file control takes the file descriptor out of batch write mode 1140 ** so that all subsequent write operations are independent. 1141 ** ^SQLite will never invoke SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE without 1142 ** a prior successful call to [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE]. 1143 ** 1144 ** <li>[[SQLITE_FCNTL_LOCK_TIMEOUT]] 1145 ** The [SQLITE_FCNTL_LOCK_TIMEOUT] opcode is used to configure a VFS 1146 ** to block for up to M milliseconds before failing when attempting to 1147 ** obtain a file lock using the xLock or xShmLock methods of the VFS. 1148 ** The parameter is a pointer to a 32-bit signed integer that contains 1149 ** the value that M is to be set to. Before returning, the 32-bit signed 1150 ** integer is overwritten with the previous value of M. 1151 ** 1152 ** <li>[[SQLITE_FCNTL_DATA_VERSION]] 1153 ** The [SQLITE_FCNTL_DATA_VERSION] opcode is used to detect changes to 1154 ** a database file. The argument is a pointer to a 32-bit unsigned integer. 1155 ** The "data version" for the pager is written into the pointer. The 1156 ** "data version" changes whenever any change occurs to the corresponding 1157 ** database file, either through SQL statements on the same database 1158 ** connection or through transactions committed by separate database 1159 ** connections possibly in other processes. The [sqlite3_total_changes()] 1160 ** interface can be used to find if any database on the connection has changed, 1161 ** but that interface responds to changes on TEMP as well as MAIN and does 1162 ** not provide a mechanism to detect changes to MAIN only. Also, the 1163 ** [sqlite3_total_changes()] interface responds to internal changes only and 1164 ** omits changes made by other database connections. The 1165 ** [PRAGMA data_version] command provides a mechanism to detect changes to 1166 ** a single attached database that occur due to other database connections, 1167 ** but omits changes implemented by the database connection on which it is 1168 ** called. This file control is the only mechanism to detect changes that 1169 ** happen either internally or externally and that are associated with 1170 ** a particular attached database. 1171 ** 1172 ** <li>[[SQLITE_FCNTL_CKPT_START]] 1173 ** The [SQLITE_FCNTL_CKPT_START] opcode is invoked from within a checkpoint 1174 ** in wal mode before the client starts to copy pages from the wal 1175 ** file to the database file. 1176 ** 1177 ** <li>[[SQLITE_FCNTL_CKPT_DONE]] 1178 ** The [SQLITE_FCNTL_CKPT_DONE] opcode is invoked from within a checkpoint 1179 ** in wal mode after the client has finished copying pages from the wal 1180 ** file to the database file, but before the *-shm file is updated to 1181 ** record the fact that the pages have been checkpointed. 1182 ** 1183 ** <li>[[SQLITE_FCNTL_EXTERNAL_READER]] 1184 ** The EXPERIMENTAL [SQLITE_FCNTL_EXTERNAL_READER] opcode is used to detect 1185 ** whether or not there is a database client in another process with a wal-mode 1186 ** transaction open on the database or not. It is only available on unix.The 1187 ** (void*) argument passed with this file-control should be a pointer to a 1188 ** value of type (int). The integer value is set to 1 if the database is a wal 1189 ** mode database and there exists at least one client in another process that 1190 ** currently has an SQL transaction open on the database. It is set to 0 if 1191 ** the database is not a wal-mode db, or if there is no such connection in any 1192 ** other process. This opcode cannot be used to detect transactions opened 1193 ** by clients within the current process, only within other processes. 1194 ** 1195 ** <li>[[SQLITE_FCNTL_CKSM_FILE]] 1196 ** The [SQLITE_FCNTL_CKSM_FILE] opcode is for use internally by the 1197 ** [checksum VFS shim] only. 1198 ** 1199 ** <li>[[SQLITE_FCNTL_RESET_CACHE]] 1200 ** If there is currently no transaction open on the database, and the 1201 ** database is not a temp db, then the [SQLITE_FCNTL_RESET_CACHE] file-control 1202 ** purges the contents of the in-memory page cache. If there is an open 1203 ** transaction, or if the db is a temp-db, this opcode is a no-op, not an error. 1204 ** </ul> 1205 */ 1206 #define SQLITE_FCNTL_LOCKSTATE 1 1207 #define SQLITE_FCNTL_GET_LOCKPROXYFILE 2 1208 #define SQLITE_FCNTL_SET_LOCKPROXYFILE 3 1209 #define SQLITE_FCNTL_LAST_ERRNO 4 1210 #define SQLITE_FCNTL_SIZE_HINT 5 1211 #define SQLITE_FCNTL_CHUNK_SIZE 6 1212 #define SQLITE_FCNTL_FILE_POINTER 7 1213 #define SQLITE_FCNTL_SYNC_OMITTED 8 1214 #define SQLITE_FCNTL_WIN32_AV_RETRY 9 1215 #define SQLITE_FCNTL_PERSIST_WAL 10 1216 #define SQLITE_FCNTL_OVERWRITE 11 1217 #define SQLITE_FCNTL_VFSNAME 12 1218 #define SQLITE_FCNTL_POWERSAFE_OVERWRITE 13 1219 #define SQLITE_FCNTL_PRAGMA 14 1220 #define SQLITE_FCNTL_BUSYHANDLER 15 1221 #define SQLITE_FCNTL_TEMPFILENAME 16 1222 #define SQLITE_FCNTL_MMAP_SIZE 18 1223 #define SQLITE_FCNTL_TRACE 19 1224 #define SQLITE_FCNTL_HAS_MOVED 20 1225 #define SQLITE_FCNTL_SYNC 21 1226 #define SQLITE_FCNTL_COMMIT_PHASETWO 22 1227 #define SQLITE_FCNTL_WIN32_SET_HANDLE 23 1228 #define SQLITE_FCNTL_WAL_BLOCK 24 1229 #define SQLITE_FCNTL_ZIPVFS 25 1230 #define SQLITE_FCNTL_RBU 26 1231 #define SQLITE_FCNTL_VFS_POINTER 27 1232 #define SQLITE_FCNTL_JOURNAL_POINTER 28 1233 #define SQLITE_FCNTL_WIN32_GET_HANDLE 29 1234 #define SQLITE_FCNTL_PDB 30 1235 #define SQLITE_FCNTL_BEGIN_ATOMIC_WRITE 31 1236 #define SQLITE_FCNTL_COMMIT_ATOMIC_WRITE 32 1237 #define SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE 33 1238 #define SQLITE_FCNTL_LOCK_TIMEOUT 34 1239 #define SQLITE_FCNTL_DATA_VERSION 35 1240 #define SQLITE_FCNTL_SIZE_LIMIT 36 1241 #define SQLITE_FCNTL_CKPT_DONE 37 1242 #define SQLITE_FCNTL_RESERVE_BYTES 38 1243 #define SQLITE_FCNTL_CKPT_START 39 1244 #define SQLITE_FCNTL_EXTERNAL_READER 40 1245 #define SQLITE_FCNTL_CKSM_FILE 41 1246 #define SQLITE_FCNTL_RESET_CACHE 42 1247 1248 /* deprecated names */ 1249 #define SQLITE_GET_LOCKPROXYFILE SQLITE_FCNTL_GET_LOCKPROXYFILE 1250 #define SQLITE_SET_LOCKPROXYFILE SQLITE_FCNTL_SET_LOCKPROXYFILE 1251 #define SQLITE_LAST_ERRNO SQLITE_FCNTL_LAST_ERRNO 1252 1253 1254 /* 1255 ** CAPI3REF: Mutex Handle 1256 ** 1257 ** The mutex module within SQLite defines [sqlite3_mutex] to be an 1258 ** abstract type for a mutex object. The SQLite core never looks 1259 ** at the internal representation of an [sqlite3_mutex]. It only 1260 ** deals with pointers to the [sqlite3_mutex] object. 1261 ** 1262 ** Mutexes are created using [sqlite3_mutex_alloc()]. 1263 */ 1264 typedef struct sqlite3_mutex sqlite3_mutex; 1265 1266 /* 1267 ** CAPI3REF: Loadable Extension Thunk 1268 ** 1269 ** A pointer to the opaque sqlite3_api_routines structure is passed as 1270 ** the third parameter to entry points of [loadable extensions]. This 1271 ** structure must be typedefed in order to work around compiler warnings 1272 ** on some platforms. 1273 */ 1274 typedef struct sqlite3_api_routines sqlite3_api_routines; 1275 1276 /* 1277 ** CAPI3REF: File Name 1278 ** 1279 ** Type [sqlite3_filename] is used by SQLite to pass filenames to the 1280 ** xOpen method of a [VFS]. It may be cast to (const char*) and treated 1281 ** as a normal, nul-terminated, UTF-8 buffer containing the filename, but 1282 ** may also be passed to special APIs such as: 1283 ** 1284 ** <ul> 1285 ** <li> sqlite3_filename_database() 1286 ** <li> sqlite3_filename_journal() 1287 ** <li> sqlite3_filename_wal() 1288 ** <li> sqlite3_uri_parameter() 1289 ** <li> sqlite3_uri_boolean() 1290 ** <li> sqlite3_uri_int64() 1291 ** <li> sqlite3_uri_key() 1292 ** </ul> 1293 */ 1294 typedef const char *sqlite3_filename; 1295 1296 /* 1297 ** CAPI3REF: OS Interface Object 1298 ** 1299 ** An instance of the sqlite3_vfs object defines the interface between 1300 ** the SQLite core and the underlying operating system. The "vfs" 1301 ** in the name of the object stands for "virtual file system". See 1302 ** the [VFS | VFS documentation] for further information. 1303 ** 1304 ** The VFS interface is sometimes extended by adding new methods onto 1305 ** the end. Each time such an extension occurs, the iVersion field 1306 ** is incremented. The iVersion value started out as 1 in 1307 ** SQLite [version 3.5.0] on [dateof:3.5.0], then increased to 2 1308 ** with SQLite [version 3.7.0] on [dateof:3.7.0], and then increased 1309 ** to 3 with SQLite [version 3.7.6] on [dateof:3.7.6]. Additional fields 1310 ** may be appended to the sqlite3_vfs object and the iVersion value 1311 ** may increase again in future versions of SQLite. 1312 ** Note that due to an oversight, the structure 1313 ** of the sqlite3_vfs object changed in the transition from 1314 ** SQLite [version 3.5.9] to [version 3.6.0] on [dateof:3.6.0] 1315 ** and yet the iVersion field was not increased. 1316 ** 1317 ** The szOsFile field is the size of the subclassed [sqlite3_file] 1318 ** structure used by this VFS. mxPathname is the maximum length of 1319 ** a pathname in this VFS. 1320 ** 1321 ** Registered sqlite3_vfs objects are kept on a linked list formed by 1322 ** the pNext pointer. The [sqlite3_vfs_register()] 1323 ** and [sqlite3_vfs_unregister()] interfaces manage this list 1324 ** in a thread-safe way. The [sqlite3_vfs_find()] interface 1325 ** searches the list. Neither the application code nor the VFS 1326 ** implementation should use the pNext pointer. 1327 ** 1328 ** The pNext field is the only field in the sqlite3_vfs 1329 ** structure that SQLite will ever modify. SQLite will only access 1330 ** or modify this field while holding a particular static mutex. 1331 ** The application should never modify anything within the sqlite3_vfs 1332 ** object once the object has been registered. 1333 ** 1334 ** The zName field holds the name of the VFS module. The name must 1335 ** be unique across all VFS modules. 1336 ** 1337 ** [[sqlite3_vfs.xOpen]] 1338 ** ^SQLite guarantees that the zFilename parameter to xOpen 1339 ** is either a NULL pointer or string obtained 1340 ** from xFullPathname() with an optional suffix added. 1341 ** ^If a suffix is added to the zFilename parameter, it will 1342 ** consist of a single "-" character followed by no more than 1343 ** 11 alphanumeric and/or "-" characters. 1344 ** ^SQLite further guarantees that 1345 ** the string will be valid and unchanged until xClose() is 1346 ** called. Because of the previous sentence, 1347 ** the [sqlite3_file] can safely store a pointer to the 1348 ** filename if it needs to remember the filename for some reason. 1349 ** If the zFilename parameter to xOpen is a NULL pointer then xOpen 1350 ** must invent its own temporary name for the file. ^Whenever the 1351 ** xFilename parameter is NULL it will also be the case that the 1352 ** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE]. 1353 ** 1354 ** The flags argument to xOpen() includes all bits set in 1355 ** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()] 1356 ** or [sqlite3_open16()] is used, then flags includes at least 1357 ** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. 1358 ** If xOpen() opens a file read-only then it sets *pOutFlags to 1359 ** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set. 1360 ** 1361 ** ^(SQLite will also add one of the following flags to the xOpen() 1362 ** call, depending on the object being opened: 1363 ** 1364 ** <ul> 1365 ** <li> [SQLITE_OPEN_MAIN_DB] 1366 ** <li> [SQLITE_OPEN_MAIN_JOURNAL] 1367 ** <li> [SQLITE_OPEN_TEMP_DB] 1368 ** <li> [SQLITE_OPEN_TEMP_JOURNAL] 1369 ** <li> [SQLITE_OPEN_TRANSIENT_DB] 1370 ** <li> [SQLITE_OPEN_SUBJOURNAL] 1371 ** <li> [SQLITE_OPEN_SUPER_JOURNAL] 1372 ** <li> [SQLITE_OPEN_WAL] 1373 ** </ul>)^ 1374 ** 1375 ** The file I/O implementation can use the object type flags to 1376 ** change the way it deals with files. For example, an application 1377 ** that does not care about crash recovery or rollback might make 1378 ** the open of a journal file a no-op. Writes to this journal would 1379 ** also be no-ops, and any attempt to read the journal would return 1380 ** SQLITE_IOERR. Or the implementation might recognize that a database 1381 ** file will be doing page-aligned sector reads and writes in a random 1382 ** order and set up its I/O subsystem accordingly. 1383 ** 1384 ** SQLite might also add one of the following flags to the xOpen method: 1385 ** 1386 ** <ul> 1387 ** <li> [SQLITE_OPEN_DELETEONCLOSE] 1388 ** <li> [SQLITE_OPEN_EXCLUSIVE] 1389 ** </ul> 1390 ** 1391 ** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be 1392 ** deleted when it is closed. ^The [SQLITE_OPEN_DELETEONCLOSE] 1393 ** will be set for TEMP databases and their journals, transient 1394 ** databases, and subjournals. 1395 ** 1396 ** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction 1397 ** with the [SQLITE_OPEN_CREATE] flag, which are both directly 1398 ** analogous to the O_EXCL and O_CREAT flags of the POSIX open() 1399 ** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the 1400 ** SQLITE_OPEN_CREATE, is used to indicate that file should always 1401 ** be created, and that it is an error if it already exists. 1402 ** It is <i>not</i> used to indicate the file should be opened 1403 ** for exclusive access. 1404 ** 1405 ** ^At least szOsFile bytes of memory are allocated by SQLite 1406 ** to hold the [sqlite3_file] structure passed as the third 1407 ** argument to xOpen. The xOpen method does not have to 1408 ** allocate the structure; it should just fill it in. Note that 1409 ** the xOpen method must set the sqlite3_file.pMethods to either 1410 ** a valid [sqlite3_io_methods] object or to NULL. xOpen must do 1411 ** this even if the open fails. SQLite expects that the sqlite3_file.pMethods 1412 ** element will be valid after xOpen returns regardless of the success 1413 ** or failure of the xOpen call. 1414 ** 1415 ** [[sqlite3_vfs.xAccess]] 1416 ** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS] 1417 ** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to 1418 ** test whether a file is readable and writable, or [SQLITE_ACCESS_READ] 1419 ** to test whether a file is at least readable. The SQLITE_ACCESS_READ 1420 ** flag is never actually used and is not implemented in the built-in 1421 ** VFSes of SQLite. The file is named by the second argument and can be a 1422 ** directory. The xAccess method returns [SQLITE_OK] on success or some 1423 ** non-zero error code if there is an I/O error or if the name of 1424 ** the file given in the second argument is illegal. If SQLITE_OK 1425 ** is returned, then non-zero or zero is written into *pResOut to indicate 1426 ** whether or not the file is accessible. 1427 ** 1428 ** ^SQLite will always allocate at least mxPathname+1 bytes for the 1429 ** output buffer xFullPathname. The exact size of the output buffer 1430 ** is also passed as a parameter to both methods. If the output buffer 1431 ** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is 1432 ** handled as a fatal error by SQLite, vfs implementations should endeavor 1433 ** to prevent this by setting mxPathname to a sufficiently large value. 1434 ** 1435 ** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64() 1436 ** interfaces are not strictly a part of the filesystem, but they are 1437 ** included in the VFS structure for completeness. 1438 ** The xRandomness() function attempts to return nBytes bytes 1439 ** of good-quality randomness into zOut. The return value is 1440 ** the actual number of bytes of randomness obtained. 1441 ** The xSleep() method causes the calling thread to sleep for at 1442 ** least the number of microseconds given. ^The xCurrentTime() 1443 ** method returns a Julian Day Number for the current date and time as 1444 ** a floating point value. 1445 ** ^The xCurrentTimeInt64() method returns, as an integer, the Julian 1446 ** Day Number multiplied by 86400000 (the number of milliseconds in 1447 ** a 24-hour day). 1448 ** ^SQLite will use the xCurrentTimeInt64() method to get the current 1449 ** date and time if that method is available (if iVersion is 2 or 1450 ** greater and the function pointer is not NULL) and will fall back 1451 ** to xCurrentTime() if xCurrentTimeInt64() is unavailable. 1452 ** 1453 ** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces 1454 ** are not used by the SQLite core. These optional interfaces are provided 1455 ** by some VFSes to facilitate testing of the VFS code. By overriding 1456 ** system calls with functions under its control, a test program can 1457 ** simulate faults and error conditions that would otherwise be difficult 1458 ** or impossible to induce. The set of system calls that can be overridden 1459 ** varies from one VFS to another, and from one version of the same VFS to the 1460 ** next. Applications that use these interfaces must be prepared for any 1461 ** or all of these interfaces to be NULL or for their behavior to change 1462 ** from one release to the next. Applications must not attempt to access 1463 ** any of these methods if the iVersion of the VFS is less than 3. 1464 */ 1465 typedef struct sqlite3_vfs sqlite3_vfs; 1466 typedef void (*sqlite3_syscall_ptr)(void); 1467 struct sqlite3_vfs { 1468 int iVersion; /* Structure version number (currently 3) */ 1469 int szOsFile; /* Size of subclassed sqlite3_file */ 1470 int mxPathname; /* Maximum file pathname length */ 1471 sqlite3_vfs *pNext; /* Next registered VFS */ 1472 const char *zName; /* Name of this virtual file system */ 1473 void *pAppData; /* Pointer to application-specific data */ 1474 int (*xOpen)(sqlite3_vfs*, sqlite3_filename zName, sqlite3_file*, 1475 int flags, int *pOutFlags); 1476 int (*xDelete)(sqlite3_vfs*, const char *zName, int syncDir); 1477 int (*xAccess)(sqlite3_vfs*, const char *zName, int flags, int *pResOut); 1478 int (*xFullPathname)(sqlite3_vfs*, const char *zName, int nOut, char *zOut); 1479 void *(*xDlOpen)(sqlite3_vfs*, const char *zFilename); 1480 void (*xDlError)(sqlite3_vfs*, int nByte, char *zErrMsg); 1481 void (*(*xDlSym)(sqlite3_vfs*,void*, const char *zSymbol))(void); 1482 void (*xDlClose)(sqlite3_vfs*, void*); 1483 int (*xRandomness)(sqlite3_vfs*, int nByte, char *zOut); 1484 int (*xSleep)(sqlite3_vfs*, int microseconds); 1485 int (*xCurrentTime)(sqlite3_vfs*, double*); 1486 int (*xGetLastError)(sqlite3_vfs*, int, char *); 1487 /* 1488 ** The methods above are in version 1 of the sqlite_vfs object 1489 ** definition. Those that follow are added in version 2 or later 1490 */ 1491 int (*xCurrentTimeInt64)(sqlite3_vfs*, sqlite3_int64*); 1492 /* 1493 ** The methods above are in versions 1 and 2 of the sqlite_vfs object. 1494 ** Those below are for version 3 and greater. 1495 */ 1496 int (*xSetSystemCall)(sqlite3_vfs*, const char *zName, sqlite3_syscall_ptr); 1497 sqlite3_syscall_ptr (*xGetSystemCall)(sqlite3_vfs*, const char *zName); 1498 const char *(*xNextSystemCall)(sqlite3_vfs*, const char *zName); 1499 /* 1500 ** The methods above are in versions 1 through 3 of the sqlite_vfs object. 1501 ** New fields may be appended in future versions. The iVersion 1502 ** value will increment whenever this happens. 1503 */ 1504 }; 1505 1506 /* 1507 ** CAPI3REF: Flags for the xAccess VFS method 1508 ** 1509 ** These integer constants can be used as the third parameter to 1510 ** the xAccess method of an [sqlite3_vfs] object. They determine 1511 ** what kind of permissions the xAccess method is looking for. 1512 ** With SQLITE_ACCESS_EXISTS, the xAccess method 1513 ** simply checks whether the file exists. 1514 ** With SQLITE_ACCESS_READWRITE, the xAccess method 1515 ** checks whether the named directory is both readable and writable 1516 ** (in other words, if files can be added, removed, and renamed within 1517 ** the directory). 1518 ** The SQLITE_ACCESS_READWRITE constant is currently used only by the 1519 ** [temp_store_directory pragma], though this could change in a future 1520 ** release of SQLite. 1521 ** With SQLITE_ACCESS_READ, the xAccess method 1522 ** checks whether the file is readable. The SQLITE_ACCESS_READ constant is 1523 ** currently unused, though it might be used in a future release of 1524 ** SQLite. 1525 */ 1526 #define SQLITE_ACCESS_EXISTS 0 1527 #define SQLITE_ACCESS_READWRITE 1 /* Used by PRAGMA temp_store_directory */ 1528 #define SQLITE_ACCESS_READ 2 /* Unused */ 1529 1530 /* 1531 ** CAPI3REF: Flags for the xShmLock VFS method 1532 ** 1533 ** These integer constants define the various locking operations 1534 ** allowed by the xShmLock method of [sqlite3_io_methods]. The 1535 ** following are the only legal combinations of flags to the 1536 ** xShmLock method: 1537 ** 1538 ** <ul> 1539 ** <li> SQLITE_SHM_LOCK | SQLITE_SHM_SHARED 1540 ** <li> SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE 1541 ** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED 1542 ** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE 1543 ** </ul> 1544 ** 1545 ** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as 1546 ** was given on the corresponding lock. 1547 ** 1548 ** The xShmLock method can transition between unlocked and SHARED or 1549 ** between unlocked and EXCLUSIVE. It cannot transition between SHARED 1550 ** and EXCLUSIVE. 1551 */ 1552 #define SQLITE_SHM_UNLOCK 1 1553 #define SQLITE_SHM_LOCK 2 1554 #define SQLITE_SHM_SHARED 4 1555 #define SQLITE_SHM_EXCLUSIVE 8 1556 1557 /* 1558 ** CAPI3REF: Maximum xShmLock index 1559 ** 1560 ** The xShmLock method on [sqlite3_io_methods] may use values 1561 ** between 0 and this upper bound as its "offset" argument. 1562 ** The SQLite core will never attempt to acquire or release a 1563 ** lock outside of this range 1564 */ 1565 #define SQLITE_SHM_NLOCK 8 1566 1567 1568 /* 1569 ** CAPI3REF: Initialize The SQLite Library 1570 ** 1571 ** ^The sqlite3_initialize() routine initializes the 1572 ** SQLite library. ^The sqlite3_shutdown() routine 1573 ** deallocates any resources that were allocated by sqlite3_initialize(). 1574 ** These routines are designed to aid in process initialization and 1575 ** shutdown on embedded systems. Workstation applications using 1576 ** SQLite normally do not need to invoke either of these routines. 1577 ** 1578 ** A call to sqlite3_initialize() is an "effective" call if it is 1579 ** the first time sqlite3_initialize() is invoked during the lifetime of 1580 ** the process, or if it is the first time sqlite3_initialize() is invoked 1581 ** following a call to sqlite3_shutdown(). ^(Only an effective call 1582 ** of sqlite3_initialize() does any initialization. All other calls 1583 ** are harmless no-ops.)^ 1584 ** 1585 ** A call to sqlite3_shutdown() is an "effective" call if it is the first 1586 ** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only 1587 ** an effective call to sqlite3_shutdown() does any deinitialization. 1588 ** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^ 1589 ** 1590 ** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown() 1591 ** is not. The sqlite3_shutdown() interface must only be called from a 1592 ** single thread. All open [database connections] must be closed and all 1593 ** other SQLite resources must be deallocated prior to invoking 1594 ** sqlite3_shutdown(). 1595 ** 1596 ** Among other things, ^sqlite3_initialize() will invoke 1597 ** sqlite3_os_init(). Similarly, ^sqlite3_shutdown() 1598 ** will invoke sqlite3_os_end(). 1599 ** 1600 ** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success. 1601 ** ^If for some reason, sqlite3_initialize() is unable to initialize 1602 ** the library (perhaps it is unable to allocate a needed resource such 1603 ** as a mutex) it returns an [error code] other than [SQLITE_OK]. 1604 ** 1605 ** ^The sqlite3_initialize() routine is called internally by many other 1606 ** SQLite interfaces so that an application usually does not need to 1607 ** invoke sqlite3_initialize() directly. For example, [sqlite3_open()] 1608 ** calls sqlite3_initialize() so the SQLite library will be automatically 1609 ** initialized when [sqlite3_open()] is called if it has not be initialized 1610 ** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT] 1611 ** compile-time option, then the automatic calls to sqlite3_initialize() 1612 ** are omitted and the application must call sqlite3_initialize() directly 1613 ** prior to using any other SQLite interface. For maximum portability, 1614 ** it is recommended that applications always invoke sqlite3_initialize() 1615 ** directly prior to using any other SQLite interface. Future releases 1616 ** of SQLite may require this. In other words, the behavior exhibited 1617 ** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the 1618 ** default behavior in some future release of SQLite. 1619 ** 1620 ** The sqlite3_os_init() routine does operating-system specific 1621 ** initialization of the SQLite library. The sqlite3_os_end() 1622 ** routine undoes the effect of sqlite3_os_init(). Typical tasks 1623 ** performed by these routines include allocation or deallocation 1624 ** of static resources, initialization of global variables, 1625 ** setting up a default [sqlite3_vfs] module, or setting up 1626 ** a default configuration using [sqlite3_config()]. 1627 ** 1628 ** The application should never invoke either sqlite3_os_init() 1629 ** or sqlite3_os_end() directly. The application should only invoke 1630 ** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init() 1631 ** interface is called automatically by sqlite3_initialize() and 1632 ** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate 1633 ** implementations for sqlite3_os_init() and sqlite3_os_end() 1634 ** are built into SQLite when it is compiled for Unix, Windows, or OS/2. 1635 ** When [custom builds | built for other platforms] 1636 ** (using the [SQLITE_OS_OTHER=1] compile-time 1637 ** option) the application must supply a suitable implementation for 1638 ** sqlite3_os_init() and sqlite3_os_end(). An application-supplied 1639 ** implementation of sqlite3_os_init() or sqlite3_os_end() 1640 ** must return [SQLITE_OK] on success and some other [error code] upon 1641 ** failure. 1642 */ 1643 SQLITE_API int sqlite3_initialize(void); 1644 SQLITE_API int sqlite3_shutdown(void); 1645 SQLITE_API int sqlite3_os_init(void); 1646 SQLITE_API int sqlite3_os_end(void); 1647 1648 /* 1649 ** CAPI3REF: Configuring The SQLite Library 1650 ** 1651 ** The sqlite3_config() interface is used to make global configuration 1652 ** changes to SQLite in order to tune SQLite to the specific needs of 1653 ** the application. The default configuration is recommended for most 1654 ** applications and so this routine is usually not necessary. It is 1655 ** provided to support rare applications with unusual needs. 1656 ** 1657 ** <b>The sqlite3_config() interface is not threadsafe. The application 1658 ** must ensure that no other SQLite interfaces are invoked by other 1659 ** threads while sqlite3_config() is running.</b> 1660 ** 1661 ** The first argument to sqlite3_config() is an integer 1662 ** [configuration option] that determines 1663 ** what property of SQLite is to be configured. Subsequent arguments 1664 ** vary depending on the [configuration option] 1665 ** in the first argument. 1666 ** 1667 ** For most configuration options, the sqlite3_config() interface 1668 ** may only be invoked prior to library initialization using 1669 ** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()]. 1670 ** The exceptional configuration options that may be invoked at any time 1671 ** are called "anytime configuration options". 1672 ** ^If sqlite3_config() is called after [sqlite3_initialize()] and before 1673 ** [sqlite3_shutdown()] with a first argument that is not an anytime 1674 ** configuration option, then the sqlite3_config() call will return SQLITE_MISUSE. 1675 ** Note, however, that ^sqlite3_config() can be called as part of the 1676 ** implementation of an application-defined [sqlite3_os_init()]. 1677 ** 1678 ** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK]. 1679 ** ^If the option is unknown or SQLite is unable to set the option 1680 ** then this routine returns a non-zero [error code]. 1681 */ 1682 SQLITE_API int sqlite3_config(int, ...); 1683 1684 /* 1685 ** CAPI3REF: Configure database connections 1686 ** METHOD: sqlite3 1687 ** 1688 ** The sqlite3_db_config() interface is used to make configuration 1689 ** changes to a [database connection]. The interface is similar to 1690 ** [sqlite3_config()] except that the changes apply to a single 1691 ** [database connection] (specified in the first argument). 1692 ** 1693 ** The second argument to sqlite3_db_config(D,V,...) is the 1694 ** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code 1695 ** that indicates what aspect of the [database connection] is being configured. 1696 ** Subsequent arguments vary depending on the configuration verb. 1697 ** 1698 ** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if 1699 ** the call is considered successful. 1700 */ 1701 SQLITE_API int sqlite3_db_config(sqlite3*, int op, ...); 1702 1703 /* 1704 ** CAPI3REF: Memory Allocation Routines 1705 ** 1706 ** An instance of this object defines the interface between SQLite 1707 ** and low-level memory allocation routines. 1708 ** 1709 ** This object is used in only one place in the SQLite interface. 1710 ** A pointer to an instance of this object is the argument to 1711 ** [sqlite3_config()] when the configuration option is 1712 ** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC]. 1713 ** By creating an instance of this object 1714 ** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC]) 1715 ** during configuration, an application can specify an alternative 1716 ** memory allocation subsystem for SQLite to use for all of its 1717 ** dynamic memory needs. 1718 ** 1719 ** Note that SQLite comes with several [built-in memory allocators] 1720 ** that are perfectly adequate for the overwhelming majority of applications 1721 ** and that this object is only useful to a tiny minority of applications 1722 ** with specialized memory allocation requirements. This object is 1723 ** also used during testing of SQLite in order to specify an alternative 1724 ** memory allocator that simulates memory out-of-memory conditions in 1725 ** order to verify that SQLite recovers gracefully from such 1726 ** conditions. 1727 ** 1728 ** The xMalloc, xRealloc, and xFree methods must work like the 1729 ** malloc(), realloc() and free() functions from the standard C library. 1730 ** ^SQLite guarantees that the second argument to 1731 ** xRealloc is always a value returned by a prior call to xRoundup. 1732 ** 1733 ** xSize should return the allocated size of a memory allocation 1734 ** previously obtained from xMalloc or xRealloc. The allocated size 1735 ** is always at least as big as the requested size but may be larger. 1736 ** 1737 ** The xRoundup method returns what would be the allocated size of 1738 ** a memory allocation given a particular requested size. Most memory 1739 ** allocators round up memory allocations at least to the next multiple 1740 ** of 8. Some allocators round up to a larger multiple or to a power of 2. 1741 ** Every memory allocation request coming in through [sqlite3_malloc()] 1742 ** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0, 1743 ** that causes the corresponding memory allocation to fail. 1744 ** 1745 ** The xInit method initializes the memory allocator. For example, 1746 ** it might allocate any required mutexes or initialize internal data 1747 ** structures. The xShutdown method is invoked (indirectly) by 1748 ** [sqlite3_shutdown()] and should deallocate any resources acquired 1749 ** by xInit. The pAppData pointer is used as the only parameter to 1750 ** xInit and xShutdown. 1751 ** 1752 ** SQLite holds the [SQLITE_MUTEX_STATIC_MAIN] mutex when it invokes 1753 ** the xInit method, so the xInit method need not be threadsafe. The 1754 ** xShutdown method is only called from [sqlite3_shutdown()] so it does 1755 ** not need to be threadsafe either. For all other methods, SQLite 1756 ** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the 1757 ** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which 1758 ** it is by default) and so the methods are automatically serialized. 1759 ** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other 1760 ** methods must be threadsafe or else make their own arrangements for 1761 ** serialization. 1762 ** 1763 ** SQLite will never invoke xInit() more than once without an intervening 1764 ** call to xShutdown(). 1765 */ 1766 typedef struct sqlite3_mem_methods sqlite3_mem_methods; 1767 struct sqlite3_mem_methods { 1768 void *(*xMalloc)(int); /* Memory allocation function */ 1769 void (*xFree)(void*); /* Free a prior allocation */ 1770 void *(*xRealloc)(void*,int); /* Resize an allocation */ 1771 int (*xSize)(void*); /* Return the size of an allocation */ 1772 int (*xRoundup)(int); /* Round up request size to allocation size */ 1773 int (*xInit)(void*); /* Initialize the memory allocator */ 1774 void (*xShutdown)(void*); /* Deinitialize the memory allocator */ 1775 void *pAppData; /* Argument to xInit() and xShutdown() */ 1776 }; 1777 1778 /* 1779 ** CAPI3REF: Configuration Options 1780 ** KEYWORDS: {configuration option} 1781 ** 1782 ** These constants are the available integer configuration options that 1783 ** can be passed as the first argument to the [sqlite3_config()] interface. 1784 ** 1785 ** Most of the configuration options for sqlite3_config() 1786 ** will only work if invoked prior to [sqlite3_initialize()] or after 1787 ** [sqlite3_shutdown()]. The few exceptions to this rule are called 1788 ** "anytime configuration options". 1789 ** ^Calling [sqlite3_config()] with a first argument that is not an 1790 ** anytime configuration option in between calls to [sqlite3_initialize()] and 1791 ** [sqlite3_shutdown()] is a no-op that returns SQLITE_MISUSE. 1792 ** 1793 ** The set of anytime configuration options can change (by insertions 1794 ** and/or deletions) from one release of SQLite to the next. 1795 ** As of SQLite version 3.42.0, the complete set of anytime configuration 1796 ** options is: 1797 ** <ul> 1798 ** <li> SQLITE_CONFIG_LOG 1799 ** <li> SQLITE_CONFIG_PCACHE_HDRSZ 1800 ** </ul> 1801 ** 1802 ** New configuration options may be added in future releases of SQLite. 1803 ** Existing configuration options might be discontinued. Applications 1804 ** should check the return code from [sqlite3_config()] to make sure that 1805 ** the call worked. The [sqlite3_config()] interface will return a 1806 ** non-zero [error code] if a discontinued or unsupported configuration option 1807 ** is invoked. 1808 ** 1809 ** <dl> 1810 ** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt> 1811 ** <dd>There are no arguments to this option. ^This option sets the 1812 ** [threading mode] to Single-thread. In other words, it disables 1813 ** all mutexing and puts SQLite into a mode where it can only be used 1814 ** by a single thread. ^If SQLite is compiled with 1815 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1816 ** it is not possible to change the [threading mode] from its default 1817 ** value of Single-thread and so [sqlite3_config()] will return 1818 ** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD 1819 ** configuration option.</dd> 1820 ** 1821 ** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt> 1822 ** <dd>There are no arguments to this option. ^This option sets the 1823 ** [threading mode] to Multi-thread. In other words, it disables 1824 ** mutexing on [database connection] and [prepared statement] objects. 1825 ** The application is responsible for serializing access to 1826 ** [database connections] and [prepared statements]. But other mutexes 1827 ** are enabled so that SQLite will be safe to use in a multi-threaded 1828 ** environment as long as no two threads attempt to use the same 1829 ** [database connection] at the same time. ^If SQLite is compiled with 1830 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1831 ** it is not possible to set the Multi-thread [threading mode] and 1832 ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the 1833 ** SQLITE_CONFIG_MULTITHREAD configuration option.</dd> 1834 ** 1835 ** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt> 1836 ** <dd>There are no arguments to this option. ^This option sets the 1837 ** [threading mode] to Serialized. In other words, this option enables 1838 ** all mutexes including the recursive 1839 ** mutexes on [database connection] and [prepared statement] objects. 1840 ** In this mode (which is the default when SQLite is compiled with 1841 ** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access 1842 ** to [database connections] and [prepared statements] so that the 1843 ** application is free to use the same [database connection] or the 1844 ** same [prepared statement] in different threads at the same time. 1845 ** ^If SQLite is compiled with 1846 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1847 ** it is not possible to set the Serialized [threading mode] and 1848 ** [sqlite3_config()] will return [SQLITE_ERROR] if called with the 1849 ** SQLITE_CONFIG_SERIALIZED configuration option.</dd> 1850 ** 1851 ** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt> 1852 ** <dd> ^(The SQLITE_CONFIG_MALLOC option takes a single argument which is 1853 ** a pointer to an instance of the [sqlite3_mem_methods] structure. 1854 ** The argument specifies 1855 ** alternative low-level memory allocation routines to be used in place of 1856 ** the memory allocation routines built into SQLite.)^ ^SQLite makes 1857 ** its own private copy of the content of the [sqlite3_mem_methods] structure 1858 ** before the [sqlite3_config()] call returns.</dd> 1859 ** 1860 ** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt> 1861 ** <dd> ^(The SQLITE_CONFIG_GETMALLOC option takes a single argument which 1862 ** is a pointer to an instance of the [sqlite3_mem_methods] structure. 1863 ** The [sqlite3_mem_methods] 1864 ** structure is filled with the currently defined memory allocation routines.)^ 1865 ** This option can be used to overload the default memory allocation 1866 ** routines with a wrapper that simulations memory allocation failure or 1867 ** tracks memory usage, for example. </dd> 1868 ** 1869 ** [[SQLITE_CONFIG_SMALL_MALLOC]] <dt>SQLITE_CONFIG_SMALL_MALLOC</dt> 1870 ** <dd> ^The SQLITE_CONFIG_SMALL_MALLOC option takes single argument of 1871 ** type int, interpreted as a boolean, which if true provides a hint to 1872 ** SQLite that it should avoid large memory allocations if possible. 1873 ** SQLite will run faster if it is free to make large memory allocations, 1874 ** but some application might prefer to run slower in exchange for 1875 ** guarantees about memory fragmentation that are possible if large 1876 ** allocations are avoided. This hint is normally off. 1877 ** </dd> 1878 ** 1879 ** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt> 1880 ** <dd> ^The SQLITE_CONFIG_MEMSTATUS option takes single argument of type int, 1881 ** interpreted as a boolean, which enables or disables the collection of 1882 ** memory allocation statistics. ^(When memory allocation statistics are 1883 ** disabled, the following SQLite interfaces become non-operational: 1884 ** <ul> 1885 ** <li> [sqlite3_hard_heap_limit64()] 1886 ** <li> [sqlite3_memory_used()] 1887 ** <li> [sqlite3_memory_highwater()] 1888 ** <li> [sqlite3_soft_heap_limit64()] 1889 ** <li> [sqlite3_status64()] 1890 ** </ul>)^ 1891 ** ^Memory allocation statistics are enabled by default unless SQLite is 1892 ** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory 1893 ** allocation statistics are disabled by default. 1894 ** </dd> 1895 ** 1896 ** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt> 1897 ** <dd> The SQLITE_CONFIG_SCRATCH option is no longer used. 1898 ** </dd> 1899 ** 1900 ** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt> 1901 ** <dd> ^The SQLITE_CONFIG_PAGECACHE option specifies a memory pool 1902 ** that SQLite can use for the database page cache with the default page 1903 ** cache implementation. 1904 ** This configuration option is a no-op if an application-defined page 1905 ** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2]. 1906 ** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to 1907 ** 8-byte aligned memory (pMem), the size of each page cache line (sz), 1908 ** and the number of cache lines (N). 1909 ** The sz argument should be the size of the largest database page 1910 ** (a power of two between 512 and 65536) plus some extra bytes for each 1911 ** page header. ^The number of extra bytes needed by the page header 1912 ** can be determined using [SQLITE_CONFIG_PCACHE_HDRSZ]. 1913 ** ^It is harmless, apart from the wasted memory, 1914 ** for the sz parameter to be larger than necessary. The pMem 1915 ** argument must be either a NULL pointer or a pointer to an 8-byte 1916 ** aligned block of memory of at least sz*N bytes, otherwise 1917 ** subsequent behavior is undefined. 1918 ** ^When pMem is not NULL, SQLite will strive to use the memory provided 1919 ** to satisfy page cache needs, falling back to [sqlite3_malloc()] if 1920 ** a page cache line is larger than sz bytes or if all of the pMem buffer 1921 ** is exhausted. 1922 ** ^If pMem is NULL and N is non-zero, then each database connection 1923 ** does an initial bulk allocation for page cache memory 1924 ** from [sqlite3_malloc()] sufficient for N cache lines if N is positive or 1925 ** of -1024*N bytes if N is negative, . ^If additional 1926 ** page cache memory is needed beyond what is provided by the initial 1927 ** allocation, then SQLite goes to [sqlite3_malloc()] separately for each 1928 ** additional cache line. </dd> 1929 ** 1930 ** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt> 1931 ** <dd> ^The SQLITE_CONFIG_HEAP option specifies a static memory buffer 1932 ** that SQLite will use for all of its dynamic memory allocation needs 1933 ** beyond those provided for by [SQLITE_CONFIG_PAGECACHE]. 1934 ** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled 1935 ** with either [SQLITE_ENABLE_MEMSYS3] or [SQLITE_ENABLE_MEMSYS5] and returns 1936 ** [SQLITE_ERROR] if invoked otherwise. 1937 ** ^There are three arguments to SQLITE_CONFIG_HEAP: 1938 ** An 8-byte aligned pointer to the memory, 1939 ** the number of bytes in the memory buffer, and the minimum allocation size. 1940 ** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts 1941 ** to using its default memory allocator (the system malloc() implementation), 1942 ** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the 1943 ** memory pointer is not NULL then the alternative memory 1944 ** allocator is engaged to handle all of SQLites memory allocation needs. 1945 ** The first pointer (the memory pointer) must be aligned to an 8-byte 1946 ** boundary or subsequent behavior of SQLite will be undefined. 1947 ** The minimum allocation size is capped at 2**12. Reasonable values 1948 ** for the minimum allocation size are 2**5 through 2**8.</dd> 1949 ** 1950 ** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt> 1951 ** <dd> ^(The SQLITE_CONFIG_MUTEX option takes a single argument which is a 1952 ** pointer to an instance of the [sqlite3_mutex_methods] structure. 1953 ** The argument specifies alternative low-level mutex routines to be used 1954 ** in place the mutex routines built into SQLite.)^ ^SQLite makes a copy of 1955 ** the content of the [sqlite3_mutex_methods] structure before the call to 1956 ** [sqlite3_config()] returns. ^If SQLite is compiled with 1957 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1958 ** the entire mutexing subsystem is omitted from the build and hence calls to 1959 ** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will 1960 ** return [SQLITE_ERROR].</dd> 1961 ** 1962 ** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt> 1963 ** <dd> ^(The SQLITE_CONFIG_GETMUTEX option takes a single argument which 1964 ** is a pointer to an instance of the [sqlite3_mutex_methods] structure. The 1965 ** [sqlite3_mutex_methods] 1966 ** structure is filled with the currently defined mutex routines.)^ 1967 ** This option can be used to overload the default mutex allocation 1968 ** routines with a wrapper used to track mutex usage for performance 1969 ** profiling or testing, for example. ^If SQLite is compiled with 1970 ** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then 1971 ** the entire mutexing subsystem is omitted from the build and hence calls to 1972 ** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will 1973 ** return [SQLITE_ERROR].</dd> 1974 ** 1975 ** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt> 1976 ** <dd> ^(The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine 1977 ** the default size of lookaside memory on each [database connection]. 1978 ** The first argument is the 1979 ** size of each lookaside buffer slot and the second is the number of 1980 ** slots allocated to each database connection.)^ ^(SQLITE_CONFIG_LOOKASIDE 1981 ** sets the <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE] 1982 ** option to [sqlite3_db_config()] can be used to change the lookaside 1983 ** configuration on individual connections.)^ </dd> 1984 ** 1985 ** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt> 1986 ** <dd> ^(The SQLITE_CONFIG_PCACHE2 option takes a single argument which is 1987 ** a pointer to an [sqlite3_pcache_methods2] object. This object specifies 1988 ** the interface to a custom page cache implementation.)^ 1989 ** ^SQLite makes a copy of the [sqlite3_pcache_methods2] object.</dd> 1990 ** 1991 ** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt> 1992 ** <dd> ^(The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which 1993 ** is a pointer to an [sqlite3_pcache_methods2] object. SQLite copies of 1994 ** the current page cache implementation into that object.)^ </dd> 1995 ** 1996 ** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt> 1997 ** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite 1998 ** global [error log]. 1999 ** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a 2000 ** function with a call signature of void(*)(void*,int,const char*), 2001 ** and a pointer to void. ^If the function pointer is not NULL, it is 2002 ** invoked by [sqlite3_log()] to process each logging event. ^If the 2003 ** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op. 2004 ** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is 2005 ** passed through as the first parameter to the application-defined logger 2006 ** function whenever that function is invoked. ^The second parameter to 2007 ** the logger function is a copy of the first parameter to the corresponding 2008 ** [sqlite3_log()] call and is intended to be a [result code] or an 2009 ** [extended result code]. ^The third parameter passed to the logger is 2010 ** log message after formatting via [sqlite3_snprintf()]. 2011 ** The SQLite logging interface is not reentrant; the logger function 2012 ** supplied by the application must not invoke any SQLite interface. 2013 ** In a multi-threaded application, the application-defined logger 2014 ** function must be threadsafe. </dd> 2015 ** 2016 ** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI 2017 ** <dd>^(The SQLITE_CONFIG_URI option takes a single argument of type int. 2018 ** If non-zero, then URI handling is globally enabled. If the parameter is zero, 2019 ** then URI handling is globally disabled.)^ ^If URI handling is globally 2020 ** enabled, all filenames passed to [sqlite3_open()], [sqlite3_open_v2()], 2021 ** [sqlite3_open16()] or 2022 ** specified as part of [ATTACH] commands are interpreted as URIs, regardless 2023 ** of whether or not the [SQLITE_OPEN_URI] flag is set when the database 2024 ** connection is opened. ^If it is globally disabled, filenames are 2025 ** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the 2026 ** database connection is opened. ^(By default, URI handling is globally 2027 ** disabled. The default value may be changed by compiling with the 2028 ** [SQLITE_USE_URI] symbol defined.)^ 2029 ** 2030 ** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN 2031 ** <dd>^The SQLITE_CONFIG_COVERING_INDEX_SCAN option takes a single integer 2032 ** argument which is interpreted as a boolean in order to enable or disable 2033 ** the use of covering indices for full table scans in the query optimizer. 2034 ** ^The default setting is determined 2035 ** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on" 2036 ** if that compile-time option is omitted. 2037 ** The ability to disable the use of covering indices for full table scans 2038 ** is because some incorrectly coded legacy applications might malfunction 2039 ** when the optimization is enabled. Providing the ability to 2040 ** disable the optimization allows the older, buggy application code to work 2041 ** without change even with newer versions of SQLite. 2042 ** 2043 ** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]] 2044 ** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE 2045 ** <dd> These options are obsolete and should not be used by new code. 2046 ** They are retained for backwards compatibility but are now no-ops. 2047 ** </dd> 2048 ** 2049 ** [[SQLITE_CONFIG_SQLLOG]] 2050 ** <dt>SQLITE_CONFIG_SQLLOG 2051 ** <dd>This option is only available if sqlite is compiled with the 2052 ** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should 2053 ** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int). 2054 ** The second should be of type (void*). The callback is invoked by the library 2055 ** in three separate circumstances, identified by the value passed as the 2056 ** fourth parameter. If the fourth parameter is 0, then the database connection 2057 ** passed as the second argument has just been opened. The third argument 2058 ** points to a buffer containing the name of the main database file. If the 2059 ** fourth parameter is 1, then the SQL statement that the third parameter 2060 ** points to has just been executed. Or, if the fourth parameter is 2, then 2061 ** the connection being passed as the second parameter is being closed. The 2062 ** third parameter is passed NULL In this case. An example of using this 2063 ** configuration option can be seen in the "test_sqllog.c" source file in 2064 ** the canonical SQLite source tree.</dd> 2065 ** 2066 ** [[SQLITE_CONFIG_MMAP_SIZE]] 2067 ** <dt>SQLITE_CONFIG_MMAP_SIZE 2068 ** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values 2069 ** that are the default mmap size limit (the default setting for 2070 ** [PRAGMA mmap_size]) and the maximum allowed mmap size limit. 2071 ** ^The default setting can be overridden by each database connection using 2072 ** either the [PRAGMA mmap_size] command, or by using the 2073 ** [SQLITE_FCNTL_MMAP_SIZE] file control. ^(The maximum allowed mmap size 2074 ** will be silently truncated if necessary so that it does not exceed the 2075 ** compile-time maximum mmap size set by the 2076 ** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^ 2077 ** ^If either argument to this option is negative, then that argument is 2078 ** changed to its compile-time default. 2079 ** 2080 ** [[SQLITE_CONFIG_WIN32_HEAPSIZE]] 2081 ** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE 2082 ** <dd>^The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is 2083 ** compiled for Windows with the [SQLITE_WIN32_MALLOC] pre-processor macro 2084 ** defined. ^SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value 2085 ** that specifies the maximum size of the created heap. 2086 ** 2087 ** [[SQLITE_CONFIG_PCACHE_HDRSZ]] 2088 ** <dt>SQLITE_CONFIG_PCACHE_HDRSZ 2089 ** <dd>^The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which 2090 ** is a pointer to an integer and writes into that integer the number of extra 2091 ** bytes per page required for each page in [SQLITE_CONFIG_PAGECACHE]. 2092 ** The amount of extra space required can change depending on the compiler, 2093 ** target platform, and SQLite version. 2094 ** 2095 ** [[SQLITE_CONFIG_PMASZ]] 2096 ** <dt>SQLITE_CONFIG_PMASZ 2097 ** <dd>^The SQLITE_CONFIG_PMASZ option takes a single parameter which 2098 ** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded 2099 ** sorter to that integer. The default minimum PMA Size is set by the 2100 ** [SQLITE_SORTER_PMASZ] compile-time option. New threads are launched 2101 ** to help with sort operations when multithreaded sorting 2102 ** is enabled (using the [PRAGMA threads] command) and the amount of content 2103 ** to be sorted exceeds the page size times the minimum of the 2104 ** [PRAGMA cache_size] setting and this value. 2105 ** 2106 ** [[SQLITE_CONFIG_STMTJRNL_SPILL]] 2107 ** <dt>SQLITE_CONFIG_STMTJRNL_SPILL 2108 ** <dd>^The SQLITE_CONFIG_STMTJRNL_SPILL option takes a single parameter which 2109 ** becomes the [statement journal] spill-to-disk threshold. 2110 ** [Statement journals] are held in memory until their size (in bytes) 2111 ** exceeds this threshold, at which point they are written to disk. 2112 ** Or if the threshold is -1, statement journals are always held 2113 ** exclusively in memory. 2114 ** Since many statement journals never become large, setting the spill 2115 ** threshold to a value such as 64KiB can greatly reduce the amount of 2116 ** I/O required to support statement rollback. 2117 ** The default value for this setting is controlled by the 2118 ** [SQLITE_STMTJRNL_SPILL] compile-time option. 2119 ** 2120 ** [[SQLITE_CONFIG_SORTERREF_SIZE]] 2121 ** <dt>SQLITE_CONFIG_SORTERREF_SIZE 2122 ** <dd>The SQLITE_CONFIG_SORTERREF_SIZE option accepts a single parameter 2123 ** of type (int) - the new value of the sorter-reference size threshold. 2124 ** Usually, when SQLite uses an external sort to order records according 2125 ** to an ORDER BY clause, all fields required by the caller are present in the 2126 ** sorted records. However, if SQLite determines based on the declared type 2127 ** of a table column that its values are likely to be very large - larger 2128 ** than the configured sorter-reference size threshold - then a reference 2129 ** is stored in each sorted record and the required column values loaded 2130 ** from the database as records are returned in sorted order. The default 2131 ** value for this option is to never use this optimization. Specifying a 2132 ** negative value for this option restores the default behavior. 2133 ** This option is only available if SQLite is compiled with the 2134 ** [SQLITE_ENABLE_SORTER_REFERENCES] compile-time option. 2135 ** 2136 ** [[SQLITE_CONFIG_MEMDB_MAXSIZE]] 2137 ** <dt>SQLITE_CONFIG_MEMDB_MAXSIZE 2138 ** <dd>The SQLITE_CONFIG_MEMDB_MAXSIZE option accepts a single parameter 2139 ** [sqlite3_int64] parameter which is the default maximum size for an in-memory 2140 ** database created using [sqlite3_deserialize()]. This default maximum 2141 ** size can be adjusted up or down for individual databases using the 2142 ** [SQLITE_FCNTL_SIZE_LIMIT] [sqlite3_file_control|file-control]. If this 2143 ** configuration setting is never used, then the default maximum is determined 2144 ** by the [SQLITE_MEMDB_DEFAULT_MAXSIZE] compile-time option. If that 2145 ** compile-time option is not set, then the default maximum is 1073741824. 2146 ** 2147 ** [[SQLITE_CONFIG_ROWID_IN_VIEW]] 2148 ** <dt>SQLITE_CONFIG_ROWID_IN_VIEW 2149 ** <dd>The SQLITE_CONFIG_ROWID_IN_VIEW option enables or disables the ability 2150 ** for VIEWs to have a ROWID. The capability can only be enabled if SQLite is 2151 ** compiled with -DSQLITE_ALLOW_ROWID_IN_VIEW, in which case the capability 2152 ** defaults to on. This configuration option queries the current setting or 2153 ** changes the setting to off or on. The argument is a pointer to an integer. 2154 ** If that integer initially holds a value of 1, then the ability for VIEWs to 2155 ** have ROWIDs is activated. If the integer initially holds zero, then the 2156 ** ability is deactivated. Any other initial value for the integer leaves the 2157 ** setting unchanged. After changes, if any, the integer is written with 2158 ** a 1 or 0, if the ability for VIEWs to have ROWIDs is on or off. If SQLite 2159 ** is compiled without -DSQLITE_ALLOW_ROWID_IN_VIEW (which is the usual and 2160 ** recommended case) then the integer is always filled with zero, regardless 2161 ** if its initial value. 2162 ** </dl> 2163 */ 2164 #define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */ 2165 #define SQLITE_CONFIG_MULTITHREAD 2 /* nil */ 2166 #define SQLITE_CONFIG_SERIALIZED 3 /* nil */ 2167 #define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */ 2168 #define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */ 2169 #define SQLITE_CONFIG_SCRATCH 6 /* No longer used */ 2170 #define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */ 2171 #define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */ 2172 #define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */ 2173 #define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */ 2174 #define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* */ 2175 /* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */ 2176 #define SQLITE_CONFIG_LOOKASIDE 13 /* int int */ 2177 #define SQLITE_CONFIG_PCACHE 14 /* no-op */ 2178 #define SQLITE_CONFIG_GETPCACHE 15 /* no-op */ 2179 #define SQLITE_CONFIG_LOG 16 /* xFunc, void* */ 2180 #define SQLITE_CONFIG_URI 17 /* int */ 2181 #define SQLITE_CONFIG_PCACHE2 18 /* sqlite3_pcache_methods2* */ 2182 #define SQLITE_CONFIG_GETPCACHE2 19 /* sqlite3_pcache_methods2* */ 2183 #define SQLITE_CONFIG_COVERING_INDEX_SCAN 20 /* int */ 2184 #define SQLITE_CONFIG_SQLLOG 21 /* xSqllog, void* */ 2185 #define SQLITE_CONFIG_MMAP_SIZE 22 /* sqlite3_int64, sqlite3_int64 */ 2186 #define SQLITE_CONFIG_WIN32_HEAPSIZE 23 /* int nByte */ 2187 #define SQLITE_CONFIG_PCACHE_HDRSZ 24 /* int *psz */ 2188 #define SQLITE_CONFIG_PMASZ 25 /* unsigned int szPma */ 2189 #define SQLITE_CONFIG_STMTJRNL_SPILL 26 /* int nByte */ 2190 #define SQLITE_CONFIG_SMALL_MALLOC 27 /* boolean */ 2191 #define SQLITE_CONFIG_SORTERREF_SIZE 28 /* int nByte */ 2192 #define SQLITE_CONFIG_MEMDB_MAXSIZE 29 /* sqlite3_int64 */ 2193 #define SQLITE_CONFIG_ROWID_IN_VIEW 30 /* int* */ 2194 2195 /* 2196 ** CAPI3REF: Database Connection Configuration Options 2197 ** 2198 ** These constants are the available integer configuration options that 2199 ** can be passed as the second argument to the [sqlite3_db_config()] interface. 2200 ** 2201 ** New configuration options may be added in future releases of SQLite. 2202 ** Existing configuration options might be discontinued. Applications 2203 ** should check the return code from [sqlite3_db_config()] to make sure that 2204 ** the call worked. ^The [sqlite3_db_config()] interface will return a 2205 ** non-zero [error code] if a discontinued or unsupported configuration option 2206 ** is invoked. 2207 ** 2208 ** <dl> 2209 ** [[SQLITE_DBCONFIG_LOOKASIDE]] 2210 ** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt> 2211 ** <dd> ^This option takes three additional arguments that determine the 2212 ** [lookaside memory allocator] configuration for the [database connection]. 2213 ** ^The first argument (the third parameter to [sqlite3_db_config()] is a 2214 ** pointer to a memory buffer to use for lookaside memory. 2215 ** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb 2216 ** may be NULL in which case SQLite will allocate the 2217 ** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the 2218 ** size of each lookaside buffer slot. ^The third argument is the number of 2219 ** slots. The size of the buffer in the first argument must be greater than 2220 ** or equal to the product of the second and third arguments. The buffer 2221 ** must be aligned to an 8-byte boundary. ^If the second argument to 2222 ** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally 2223 ** rounded down to the next smaller multiple of 8. ^(The lookaside memory 2224 ** configuration for a database connection can only be changed when that 2225 ** connection is not currently using lookaside memory, or in other words 2226 ** when the "current value" returned by 2227 ** [sqlite3_db_status](D,[SQLITE_DBSTATUS_LOOKASIDE_USED],...) is zero. 2228 ** Any attempt to change the lookaside memory configuration when lookaside 2229 ** memory is in use leaves the configuration unchanged and returns 2230 ** [SQLITE_BUSY].)^</dd> 2231 ** 2232 ** [[SQLITE_DBCONFIG_ENABLE_FKEY]] 2233 ** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt> 2234 ** <dd> ^This option is used to enable or disable the enforcement of 2235 ** [foreign key constraints]. There should be two additional arguments. 2236 ** The first argument is an integer which is 0 to disable FK enforcement, 2237 ** positive to enable FK enforcement or negative to leave FK enforcement 2238 ** unchanged. The second parameter is a pointer to an integer into which 2239 ** is written 0 or 1 to indicate whether FK enforcement is off or on 2240 ** following this call. The second parameter may be a NULL pointer, in 2241 ** which case the FK enforcement setting is not reported back. </dd> 2242 ** 2243 ** [[SQLITE_DBCONFIG_ENABLE_TRIGGER]] 2244 ** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt> 2245 ** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers]. 2246 ** There should be two additional arguments. 2247 ** The first argument is an integer which is 0 to disable triggers, 2248 ** positive to enable triggers or negative to leave the setting unchanged. 2249 ** The second parameter is a pointer to an integer into which 2250 ** is written 0 or 1 to indicate whether triggers are disabled or enabled 2251 ** following this call. The second parameter may be a NULL pointer, in 2252 ** which case the trigger setting is not reported back. 2253 ** 2254 ** <p>Originally this option disabled all triggers. ^(However, since 2255 ** SQLite version 3.35.0, TEMP triggers are still allowed even if 2256 ** this option is off. So, in other words, this option now only disables 2257 ** triggers in the main database schema or in the schemas of ATTACH-ed 2258 ** databases.)^ </dd> 2259 ** 2260 ** [[SQLITE_DBCONFIG_ENABLE_VIEW]] 2261 ** <dt>SQLITE_DBCONFIG_ENABLE_VIEW</dt> 2262 ** <dd> ^This option is used to enable or disable [CREATE VIEW | views]. 2263 ** There should be two additional arguments. 2264 ** The first argument is an integer which is 0 to disable views, 2265 ** positive to enable views or negative to leave the setting unchanged. 2266 ** The second parameter is a pointer to an integer into which 2267 ** is written 0 or 1 to indicate whether views are disabled or enabled 2268 ** following this call. The second parameter may be a NULL pointer, in 2269 ** which case the view setting is not reported back. 2270 ** 2271 ** <p>Originally this option disabled all views. ^(However, since 2272 ** SQLite version 3.35.0, TEMP views are still allowed even if 2273 ** this option is off. So, in other words, this option now only disables 2274 ** views in the main database schema or in the schemas of ATTACH-ed 2275 ** databases.)^ </dd> 2276 ** 2277 ** [[SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER]] 2278 ** <dt>SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER</dt> 2279 ** <dd> ^This option is used to enable or disable the 2280 ** [fts3_tokenizer()] function which is part of the 2281 ** [FTS3] full-text search engine extension. 2282 ** There should be two additional arguments. 2283 ** The first argument is an integer which is 0 to disable fts3_tokenizer() or 2284 ** positive to enable fts3_tokenizer() or negative to leave the setting 2285 ** unchanged. 2286 ** The second parameter is a pointer to an integer into which 2287 ** is written 0 or 1 to indicate whether fts3_tokenizer is disabled or enabled 2288 ** following this call. The second parameter may be a NULL pointer, in 2289 ** which case the new setting is not reported back. </dd> 2290 ** 2291 ** [[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION]] 2292 ** <dt>SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION</dt> 2293 ** <dd> ^This option is used to enable or disable the [sqlite3_load_extension()] 2294 ** interface independently of the [load_extension()] SQL function. 2295 ** The [sqlite3_enable_load_extension()] API enables or disables both the 2296 ** C-API [sqlite3_load_extension()] and the SQL function [load_extension()]. 2297 ** There should be two additional arguments. 2298 ** When the first argument to this interface is 1, then only the C-API is 2299 ** enabled and the SQL function remains disabled. If the first argument to 2300 ** this interface is 0, then both the C-API and the SQL function are disabled. 2301 ** If the first argument is -1, then no changes are made to state of either the 2302 ** C-API or the SQL function. 2303 ** The second parameter is a pointer to an integer into which 2304 ** is written 0 or 1 to indicate whether [sqlite3_load_extension()] interface 2305 ** is disabled or enabled following this call. The second parameter may 2306 ** be a NULL pointer, in which case the new setting is not reported back. 2307 ** </dd> 2308 ** 2309 ** [[SQLITE_DBCONFIG_MAINDBNAME]] <dt>SQLITE_DBCONFIG_MAINDBNAME</dt> 2310 ** <dd> ^This option is used to change the name of the "main" database 2311 ** schema. ^The sole argument is a pointer to a constant UTF8 string 2312 ** which will become the new schema name in place of "main". ^SQLite 2313 ** does not make a copy of the new main schema name string, so the application 2314 ** must ensure that the argument passed into this DBCONFIG option is unchanged 2315 ** until after the database connection closes. 2316 ** </dd> 2317 ** 2318 ** [[SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE]] 2319 ** <dt>SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE</dt> 2320 ** <dd> Usually, when a database in wal mode is closed or detached from a 2321 ** database handle, SQLite checks if this will mean that there are now no 2322 ** connections at all to the database. If so, it performs a checkpoint 2323 ** operation before closing the connection. This option may be used to 2324 ** override this behavior. The first parameter passed to this operation 2325 ** is an integer - positive to disable checkpoints-on-close, or zero (the 2326 ** default) to enable them, and negative to leave the setting unchanged. 2327 ** The second parameter is a pointer to an integer 2328 ** into which is written 0 or 1 to indicate whether checkpoints-on-close 2329 ** have been disabled - 0 if they are not disabled, 1 if they are. 2330 ** </dd> 2331 ** 2332 ** [[SQLITE_DBCONFIG_ENABLE_QPSG]] <dt>SQLITE_DBCONFIG_ENABLE_QPSG</dt> 2333 ** <dd>^(The SQLITE_DBCONFIG_ENABLE_QPSG option activates or deactivates 2334 ** the [query planner stability guarantee] (QPSG). When the QPSG is active, 2335 ** a single SQL query statement will always use the same algorithm regardless 2336 ** of values of [bound parameters].)^ The QPSG disables some query optimizations 2337 ** that look at the values of bound parameters, which can make some queries 2338 ** slower. But the QPSG has the advantage of more predictable behavior. With 2339 ** the QPSG active, SQLite will always use the same query plan in the field as 2340 ** was used during testing in the lab. 2341 ** The first argument to this setting is an integer which is 0 to disable 2342 ** the QPSG, positive to enable QPSG, or negative to leave the setting 2343 ** unchanged. The second parameter is a pointer to an integer into which 2344 ** is written 0 or 1 to indicate whether the QPSG is disabled or enabled 2345 ** following this call. 2346 ** </dd> 2347 ** 2348 ** [[SQLITE_DBCONFIG_TRIGGER_EQP]] <dt>SQLITE_DBCONFIG_TRIGGER_EQP</dt> 2349 ** <dd> By default, the output of EXPLAIN QUERY PLAN commands does not 2350 ** include output for any operations performed by trigger programs. This 2351 ** option is used to set or clear (the default) a flag that governs this 2352 ** behavior. The first parameter passed to this operation is an integer - 2353 ** positive to enable output for trigger programs, or zero to disable it, 2354 ** or negative to leave the setting unchanged. 2355 ** The second parameter is a pointer to an integer into which is written 2356 ** 0 or 1 to indicate whether output-for-triggers has been disabled - 0 if 2357 ** it is not disabled, 1 if it is. 2358 ** </dd> 2359 ** 2360 ** [[SQLITE_DBCONFIG_RESET_DATABASE]] <dt>SQLITE_DBCONFIG_RESET_DATABASE</dt> 2361 ** <dd> Set the SQLITE_DBCONFIG_RESET_DATABASE flag and then run 2362 ** [VACUUM] in order to reset a database back to an empty database 2363 ** with no schema and no content. The following process works even for 2364 ** a badly corrupted database file: 2365 ** <ol> 2366 ** <li> If the database connection is newly opened, make sure it has read the 2367 ** database schema by preparing then discarding some query against the 2368 ** database, or calling sqlite3_table_column_metadata(), ignoring any 2369 ** errors. This step is only necessary if the application desires to keep 2370 ** the database in WAL mode after the reset if it was in WAL mode before 2371 ** the reset. 2372 ** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 1, 0); 2373 ** <li> [sqlite3_exec](db, "[VACUUM]", 0, 0, 0); 2374 ** <li> sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 0, 0); 2375 ** </ol> 2376 ** Because resetting a database is destructive and irreversible, the 2377 ** process requires the use of this obscure API and multiple steps to 2378 ** help ensure that it does not happen by accident. Because this 2379 ** feature must be capable of resetting corrupt databases, and 2380 ** shutting down virtual tables may require access to that corrupt 2381 ** storage, the library must abandon any installed virtual tables 2382 ** without calling their xDestroy() methods. 2383 ** 2384 ** [[SQLITE_DBCONFIG_DEFENSIVE]] <dt>SQLITE_DBCONFIG_DEFENSIVE</dt> 2385 ** <dd>The SQLITE_DBCONFIG_DEFENSIVE option activates or deactivates the 2386 ** "defensive" flag for a database connection. When the defensive 2387 ** flag is enabled, language features that allow ordinary SQL to 2388 ** deliberately corrupt the database file are disabled. The disabled 2389 ** features include but are not limited to the following: 2390 ** <ul> 2391 ** <li> The [PRAGMA writable_schema=ON] statement. 2392 ** <li> The [PRAGMA journal_mode=OFF] statement. 2393 ** <li> The [PRAGMA schema_version=N] statement. 2394 ** <li> Writes to the [sqlite_dbpage] virtual table. 2395 ** <li> Direct writes to [shadow tables]. 2396 ** </ul> 2397 ** </dd> 2398 ** 2399 ** [[SQLITE_DBCONFIG_WRITABLE_SCHEMA]] <dt>SQLITE_DBCONFIG_WRITABLE_SCHEMA</dt> 2400 ** <dd>The SQLITE_DBCONFIG_WRITABLE_SCHEMA option activates or deactivates the 2401 ** "writable_schema" flag. This has the same effect and is logically equivalent 2402 ** to setting [PRAGMA writable_schema=ON] or [PRAGMA writable_schema=OFF]. 2403 ** The first argument to this setting is an integer which is 0 to disable 2404 ** the writable_schema, positive to enable writable_schema, or negative to 2405 ** leave the setting unchanged. The second parameter is a pointer to an 2406 ** integer into which is written 0 or 1 to indicate whether the writable_schema 2407 ** is enabled or disabled following this call. 2408 ** </dd> 2409 ** 2410 ** [[SQLITE_DBCONFIG_LEGACY_ALTER_TABLE]] 2411 ** <dt>SQLITE_DBCONFIG_LEGACY_ALTER_TABLE</dt> 2412 ** <dd>The SQLITE_DBCONFIG_LEGACY_ALTER_TABLE option activates or deactivates 2413 ** the legacy behavior of the [ALTER TABLE RENAME] command such it 2414 ** behaves as it did prior to [version 3.24.0] (2018-06-04). See the 2415 ** "Compatibility Notice" on the [ALTER TABLE RENAME documentation] for 2416 ** additional information. This feature can also be turned on and off 2417 ** using the [PRAGMA legacy_alter_table] statement. 2418 ** </dd> 2419 ** 2420 ** [[SQLITE_DBCONFIG_DQS_DML]] 2421 ** <dt>SQLITE_DBCONFIG_DQS_DML</dt> 2422 ** <dd>The SQLITE_DBCONFIG_DQS_DML option activates or deactivates 2423 ** the legacy [double-quoted string literal] misfeature for DML statements 2424 ** only, that is DELETE, INSERT, SELECT, and UPDATE statements. The 2425 ** default value of this setting is determined by the [-DSQLITE_DQS] 2426 ** compile-time option. 2427 ** </dd> 2428 ** 2429 ** [[SQLITE_DBCONFIG_DQS_DDL]] 2430 ** <dt>SQLITE_DBCONFIG_DQS_DDL</dt> 2431 ** <dd>The SQLITE_DBCONFIG_DQS option activates or deactivates 2432 ** the legacy [double-quoted string literal] misfeature for DDL statements, 2433 ** such as CREATE TABLE and CREATE INDEX. The 2434 ** default value of this setting is determined by the [-DSQLITE_DQS] 2435 ** compile-time option. 2436 ** </dd> 2437 ** 2438 ** [[SQLITE_DBCONFIG_TRUSTED_SCHEMA]] 2439 ** <dt>SQLITE_DBCONFIG_TRUSTED_SCHEMA</dt> 2440 ** <dd>The SQLITE_DBCONFIG_TRUSTED_SCHEMA option tells SQLite to 2441 ** assume that database schemas are untainted by malicious content. 2442 ** When the SQLITE_DBCONFIG_TRUSTED_SCHEMA option is disabled, SQLite 2443 ** takes additional defensive steps to protect the application from harm 2444 ** including: 2445 ** <ul> 2446 ** <li> Prohibit the use of SQL functions inside triggers, views, 2447 ** CHECK constraints, DEFAULT clauses, expression indexes, 2448 ** partial indexes, or generated columns 2449 ** unless those functions are tagged with [SQLITE_INNOCUOUS]. 2450 ** <li> Prohibit the use of virtual tables inside of triggers or views 2451 ** unless those virtual tables are tagged with [SQLITE_VTAB_INNOCUOUS]. 2452 ** </ul> 2453 ** This setting defaults to "on" for legacy compatibility, however 2454 ** all applications are advised to turn it off if possible. This setting 2455 ** can also be controlled using the [PRAGMA trusted_schema] statement. 2456 ** </dd> 2457 ** 2458 ** [[SQLITE_DBCONFIG_LEGACY_FILE_FORMAT]] 2459 ** <dt>SQLITE_DBCONFIG_LEGACY_FILE_FORMAT</dt> 2460 ** <dd>The SQLITE_DBCONFIG_LEGACY_FILE_FORMAT option activates or deactivates 2461 ** the legacy file format flag. When activated, this flag causes all newly 2462 ** created database file to have a schema format version number (the 4-byte 2463 ** integer found at offset 44 into the database header) of 1. This in turn 2464 ** means that the resulting database file will be readable and writable by 2465 ** any SQLite version back to 3.0.0 ([dateof:3.0.0]). Without this setting, 2466 ** newly created databases are generally not understandable by SQLite versions 2467 ** prior to 3.3.0 ([dateof:3.3.0]). As these words are written, there 2468 ** is now scarcely any need to generate database files that are compatible 2469 ** all the way back to version 3.0.0, and so this setting is of little 2470 ** practical use, but is provided so that SQLite can continue to claim the 2471 ** ability to generate new database files that are compatible with version 2472 ** 3.0.0. 2473 ** <p>Note that when the SQLITE_DBCONFIG_LEGACY_FILE_FORMAT setting is on, 2474 ** the [VACUUM] command will fail with an obscure error when attempting to 2475 ** process a table with generated columns and a descending index. This is 2476 ** not considered a bug since SQLite versions 3.3.0 and earlier do not support 2477 ** either generated columns or descending indexes. 2478 ** </dd> 2479 ** 2480 ** [[SQLITE_DBCONFIG_STMT_SCANSTATUS]] 2481 ** <dt>SQLITE_DBCONFIG_STMT_SCANSTATUS</dt> 2482 ** <dd>The SQLITE_DBCONFIG_STMT_SCANSTATUS option is only useful in 2483 ** SQLITE_ENABLE_STMT_SCANSTATUS builds. In this case, it sets or clears 2484 ** a flag that enables collection of the sqlite3_stmt_scanstatus_v2() 2485 ** statistics. For statistics to be collected, the flag must be set on 2486 ** the database handle both when the SQL statement is prepared and when it 2487 ** is stepped. The flag is set (collection of statistics is enabled) 2488 ** by default. This option takes two arguments: an integer and a pointer to 2489 ** an integer.. The first argument is 1, 0, or -1 to enable, disable, or 2490 ** leave unchanged the statement scanstatus option. If the second argument 2491 ** is not NULL, then the value of the statement scanstatus setting after 2492 ** processing the first argument is written into the integer that the second 2493 ** argument points to. 2494 ** </dd> 2495 ** 2496 ** [[SQLITE_DBCONFIG_REVERSE_SCANORDER]] 2497 ** <dt>SQLITE_DBCONFIG_REVERSE_SCANORDER</dt> 2498 ** <dd>The SQLITE_DBCONFIG_REVERSE_SCANORDER option changes the default order 2499 ** in which tables and indexes are scanned so that the scans start at the end 2500 ** and work toward the beginning rather than starting at the beginning and 2501 ** working toward the end. Setting SQLITE_DBCONFIG_REVERSE_SCANORDER is the 2502 ** same as setting [PRAGMA reverse_unordered_selects]. This option takes 2503 ** two arguments which are an integer and a pointer to an integer. The first 2504 ** argument is 1, 0, or -1 to enable, disable, or leave unchanged the 2505 ** reverse scan order flag, respectively. If the second argument is not NULL, 2506 ** then 0 or 1 is written into the integer that the second argument points to 2507 ** depending on if the reverse scan order flag is set after processing the 2508 ** first argument. 2509 ** </dd> 2510 ** 2511 ** </dl> 2512 */ 2513 #define SQLITE_DBCONFIG_MAINDBNAME 1000 /* const char* */ 2514 #define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */ 2515 #define SQLITE_DBCONFIG_ENABLE_FKEY 1002 /* int int* */ 2516 #define SQLITE_DBCONFIG_ENABLE_TRIGGER 1003 /* int int* */ 2517 #define SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER 1004 /* int int* */ 2518 #define SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION 1005 /* int int* */ 2519 #define SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE 1006 /* int int* */ 2520 #define SQLITE_DBCONFIG_ENABLE_QPSG 1007 /* int int* */ 2521 #define SQLITE_DBCONFIG_TRIGGER_EQP 1008 /* int int* */ 2522 #define SQLITE_DBCONFIG_RESET_DATABASE 1009 /* int int* */ 2523 #define SQLITE_DBCONFIG_DEFENSIVE 1010 /* int int* */ 2524 #define SQLITE_DBCONFIG_WRITABLE_SCHEMA 1011 /* int int* */ 2525 #define SQLITE_DBCONFIG_LEGACY_ALTER_TABLE 1012 /* int int* */ 2526 #define SQLITE_DBCONFIG_DQS_DML 1013 /* int int* */ 2527 #define SQLITE_DBCONFIG_DQS_DDL 1014 /* int int* */ 2528 #define SQLITE_DBCONFIG_ENABLE_VIEW 1015 /* int int* */ 2529 #define SQLITE_DBCONFIG_LEGACY_FILE_FORMAT 1016 /* int int* */ 2530 #define SQLITE_DBCONFIG_TRUSTED_SCHEMA 1017 /* int int* */ 2531 #define SQLITE_DBCONFIG_STMT_SCANSTATUS 1018 /* int int* */ 2532 #define SQLITE_DBCONFIG_REVERSE_SCANORDER 1019 /* int int* */ 2533 #define SQLITE_DBCONFIG_MAX 1019 /* Largest DBCONFIG */ 2534 2535 /* 2536 ** CAPI3REF: Enable Or Disable Extended Result Codes 2537 ** METHOD: sqlite3 2538 ** 2539 ** ^The sqlite3_extended_result_codes() routine enables or disables the 2540 ** [extended result codes] feature of SQLite. ^The extended result 2541 ** codes are disabled by default for historical compatibility. 2542 */ 2543 SQLITE_API int sqlite3_extended_result_codes(sqlite3*, int onoff); 2544 2545 /* 2546 ** CAPI3REF: Last Insert Rowid 2547 ** METHOD: sqlite3 2548 ** 2549 ** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables) 2550 ** has a unique 64-bit signed 2551 ** integer key called the [ROWID | "rowid"]. ^The rowid is always available 2552 ** as an undeclared column named ROWID, OID, or _ROWID_ as long as those 2553 ** names are not also used by explicitly declared columns. ^If 2554 ** the table has a column of type [INTEGER PRIMARY KEY] then that column 2555 ** is another alias for the rowid. 2556 ** 2557 ** ^The sqlite3_last_insert_rowid(D) interface usually returns the [rowid] of 2558 ** the most recent successful [INSERT] into a rowid table or [virtual table] 2559 ** on database connection D. ^Inserts into [WITHOUT ROWID] tables are not 2560 ** recorded. ^If no successful [INSERT]s into rowid tables have ever occurred 2561 ** on the database connection D, then sqlite3_last_insert_rowid(D) returns 2562 ** zero. 2563 ** 2564 ** As well as being set automatically as rows are inserted into database 2565 ** tables, the value returned by this function may be set explicitly by 2566 ** [sqlite3_set_last_insert_rowid()] 2567 ** 2568 ** Some virtual table implementations may INSERT rows into rowid tables as 2569 ** part of committing a transaction (e.g. to flush data accumulated in memory 2570 ** to disk). In this case subsequent calls to this function return the rowid 2571 ** associated with these internal INSERT operations, which leads to 2572 ** unintuitive results. Virtual table implementations that do write to rowid 2573 ** tables in this way can avoid this problem by restoring the original 2574 ** rowid value using [sqlite3_set_last_insert_rowid()] before returning 2575 ** control to the user. 2576 ** 2577 ** ^(If an [INSERT] occurs within a trigger then this routine will 2578 ** return the [rowid] of the inserted row as long as the trigger is 2579 ** running. Once the trigger program ends, the value returned 2580 ** by this routine reverts to what it was before the trigger was fired.)^ 2581 ** 2582 ** ^An [INSERT] that fails due to a constraint violation is not a 2583 ** successful [INSERT] and does not change the value returned by this 2584 ** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK, 2585 ** and INSERT OR ABORT make no changes to the return value of this 2586 ** routine when their insertion fails. ^(When INSERT OR REPLACE 2587 ** encounters a constraint violation, it does not fail. The 2588 ** INSERT continues to completion after deleting rows that caused 2589 ** the constraint problem so INSERT OR REPLACE will always change 2590 ** the return value of this interface.)^ 2591 ** 2592 ** ^For the purposes of this routine, an [INSERT] is considered to 2593 ** be successful even if it is subsequently rolled back. 2594 ** 2595 ** This function is accessible to SQL statements via the 2596 ** [last_insert_rowid() SQL function]. 2597 ** 2598 ** If a separate thread performs a new [INSERT] on the same 2599 ** database connection while the [sqlite3_last_insert_rowid()] 2600 ** function is running and thus changes the last insert [rowid], 2601 ** then the value returned by [sqlite3_last_insert_rowid()] is 2602 ** unpredictable and might not equal either the old or the new 2603 ** last insert [rowid]. 2604 */ 2605 SQLITE_API sqlite3_int64 sqlite3_last_insert_rowid(sqlite3*); 2606 2607 /* 2608 ** CAPI3REF: Set the Last Insert Rowid value. 2609 ** METHOD: sqlite3 2610 ** 2611 ** The sqlite3_set_last_insert_rowid(D, R) method allows the application to 2612 ** set the value returned by calling sqlite3_last_insert_rowid(D) to R 2613 ** without inserting a row into the database. 2614 */ 2615 SQLITE_API void sqlite3_set_last_insert_rowid(sqlite3*,sqlite3_int64); 2616 2617 /* 2618 ** CAPI3REF: Count The Number Of Rows Modified 2619 ** METHOD: sqlite3 2620 ** 2621 ** ^These functions return the number of rows modified, inserted or 2622 ** deleted by the most recently completed INSERT, UPDATE or DELETE 2623 ** statement on the database connection specified by the only parameter. 2624 ** The two functions are identical except for the type of the return value 2625 ** and that if the number of rows modified by the most recent INSERT, UPDATE 2626 ** or DELETE is greater than the maximum value supported by type "int", then 2627 ** the return value of sqlite3_changes() is undefined. ^Executing any other 2628 ** type of SQL statement does not modify the value returned by these functions. 2629 ** 2630 ** ^Only changes made directly by the INSERT, UPDATE or DELETE statement are 2631 ** considered - auxiliary changes caused by [CREATE TRIGGER | triggers], 2632 ** [foreign key actions] or [REPLACE] constraint resolution are not counted. 2633 ** 2634 ** Changes to a view that are intercepted by 2635 ** [INSTEAD OF trigger | INSTEAD OF triggers] are not counted. ^The value 2636 ** returned by sqlite3_changes() immediately after an INSERT, UPDATE or 2637 ** DELETE statement run on a view is always zero. Only changes made to real 2638 ** tables are counted. 2639 ** 2640 ** Things are more complicated if the sqlite3_changes() function is 2641 ** executed while a trigger program is running. This may happen if the 2642 ** program uses the [changes() SQL function], or if some other callback 2643 ** function invokes sqlite3_changes() directly. Essentially: 2644 ** 2645 ** <ul> 2646 ** <li> ^(Before entering a trigger program the value returned by 2647 ** sqlite3_changes() function is saved. After the trigger program 2648 ** has finished, the original value is restored.)^ 2649 ** 2650 ** <li> ^(Within a trigger program each INSERT, UPDATE and DELETE 2651 ** statement sets the value returned by sqlite3_changes() 2652 ** upon completion as normal. Of course, this value will not include 2653 ** any changes performed by sub-triggers, as the sqlite3_changes() 2654 ** value will be saved and restored after each sub-trigger has run.)^ 2655 ** </ul> 2656 ** 2657 ** ^This means that if the changes() SQL function (or similar) is used 2658 ** by the first INSERT, UPDATE or DELETE statement within a trigger, it 2659 ** returns the value as set when the calling statement began executing. 2660 ** ^If it is used by the second or subsequent such statement within a trigger 2661 ** program, the value returned reflects the number of rows modified by the 2662 ** previous INSERT, UPDATE or DELETE statement within the same trigger. 2663 ** 2664 ** If a separate thread makes changes on the same database connection 2665 ** while [sqlite3_changes()] is running then the value returned 2666 ** is unpredictable and not meaningful. 2667 ** 2668 ** See also: 2669 ** <ul> 2670 ** <li> the [sqlite3_total_changes()] interface 2671 ** <li> the [count_changes pragma] 2672 ** <li> the [changes() SQL function] 2673 ** <li> the [data_version pragma] 2674 ** </ul> 2675 */ 2676 SQLITE_API int sqlite3_changes(sqlite3*); 2677 SQLITE_API sqlite3_int64 sqlite3_changes64(sqlite3*); 2678 2679 /* 2680 ** CAPI3REF: Total Number Of Rows Modified 2681 ** METHOD: sqlite3 2682 ** 2683 ** ^These functions return the total number of rows inserted, modified or 2684 ** deleted by all [INSERT], [UPDATE] or [DELETE] statements completed 2685 ** since the database connection was opened, including those executed as 2686 ** part of trigger programs. The two functions are identical except for the 2687 ** type of the return value and that if the number of rows modified by the 2688 ** connection exceeds the maximum value supported by type "int", then 2689 ** the return value of sqlite3_total_changes() is undefined. ^Executing 2690 ** any other type of SQL statement does not affect the value returned by 2691 ** sqlite3_total_changes(). 2692 ** 2693 ** ^Changes made as part of [foreign key actions] are included in the 2694 ** count, but those made as part of REPLACE constraint resolution are 2695 ** not. ^Changes to a view that are intercepted by INSTEAD OF triggers 2696 ** are not counted. 2697 ** 2698 ** The [sqlite3_total_changes(D)] interface only reports the number 2699 ** of rows that changed due to SQL statement run against database 2700 ** connection D. Any changes by other database connections are ignored. 2701 ** To detect changes against a database file from other database 2702 ** connections use the [PRAGMA data_version] command or the 2703 ** [SQLITE_FCNTL_DATA_VERSION] [file control]. 2704 ** 2705 ** If a separate thread makes changes on the same database connection 2706 ** while [sqlite3_total_changes()] is running then the value 2707 ** returned is unpredictable and not meaningful. 2708 ** 2709 ** See also: 2710 ** <ul> 2711 ** <li> the [sqlite3_changes()] interface 2712 ** <li> the [count_changes pragma] 2713 ** <li> the [changes() SQL function] 2714 ** <li> the [data_version pragma] 2715 ** <li> the [SQLITE_FCNTL_DATA_VERSION] [file control] 2716 ** </ul> 2717 */ 2718 SQLITE_API int sqlite3_total_changes(sqlite3*); 2719 SQLITE_API sqlite3_int64 sqlite3_total_changes64(sqlite3*); 2720 2721 /* 2722 ** CAPI3REF: Interrupt A Long-Running Query 2723 ** METHOD: sqlite3 2724 ** 2725 ** ^This function causes any pending database operation to abort and 2726 ** return at its earliest opportunity. This routine is typically 2727 ** called in response to a user action such as pressing "Cancel" 2728 ** or Ctrl-C where the user wants a long query operation to halt 2729 ** immediately. 2730 ** 2731 ** ^It is safe to call this routine from a thread different from the 2732 ** thread that is currently running the database operation. But it 2733 ** is not safe to call this routine with a [database connection] that 2734 ** is closed or might close before sqlite3_interrupt() returns. 2735 ** 2736 ** ^If an SQL operation is very nearly finished at the time when 2737 ** sqlite3_interrupt() is called, then it might not have an opportunity 2738 ** to be interrupted and might continue to completion. 2739 ** 2740 ** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT]. 2741 ** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE 2742 ** that is inside an explicit transaction, then the entire transaction 2743 ** will be rolled back automatically. 2744 ** 2745 ** ^The sqlite3_interrupt(D) call is in effect until all currently running 2746 ** SQL statements on [database connection] D complete. ^Any new SQL statements 2747 ** that are started after the sqlite3_interrupt() call and before the 2748 ** running statement count reaches zero are interrupted as if they had been 2749 ** running prior to the sqlite3_interrupt() call. ^New SQL statements 2750 ** that are started after the running statement count reaches zero are 2751 ** not effected by the sqlite3_interrupt(). 2752 ** ^A call to sqlite3_interrupt(D) that occurs when there are no running 2753 ** SQL statements is a no-op and has no effect on SQL statements 2754 ** that are started after the sqlite3_interrupt() call returns. 2755 ** 2756 ** ^The [sqlite3_is_interrupted(D)] interface can be used to determine whether 2757 ** or not an interrupt is currently in effect for [database connection] D. 2758 ** It returns 1 if an interrupt is currently in effect, or 0 otherwise. 2759 */ 2760 SQLITE_API void sqlite3_interrupt(sqlite3*); 2761 SQLITE_API int sqlite3_is_interrupted(sqlite3*); 2762 2763 /* 2764 ** CAPI3REF: Determine If An SQL Statement Is Complete 2765 ** 2766 ** These routines are useful during command-line input to determine if the 2767 ** currently entered text seems to form a complete SQL statement or 2768 ** if additional input is needed before sending the text into 2769 ** SQLite for parsing. ^These routines return 1 if the input string 2770 ** appears to be a complete SQL statement. ^A statement is judged to be 2771 ** complete if it ends with a semicolon token and is not a prefix of a 2772 ** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within 2773 ** string literals or quoted identifier names or comments are not 2774 ** independent tokens (they are part of the token in which they are 2775 ** embedded) and thus do not count as a statement terminator. ^Whitespace 2776 ** and comments that follow the final semicolon are ignored. 2777 ** 2778 ** ^These routines return 0 if the statement is incomplete. ^If a 2779 ** memory allocation fails, then SQLITE_NOMEM is returned. 2780 ** 2781 ** ^These routines do not parse the SQL statements thus 2782 ** will not detect syntactically incorrect SQL. 2783 ** 2784 ** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior 2785 ** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked 2786 ** automatically by sqlite3_complete16(). If that initialization fails, 2787 ** then the return value from sqlite3_complete16() will be non-zero 2788 ** regardless of whether or not the input SQL is complete.)^ 2789 ** 2790 ** The input to [sqlite3_complete()] must be a zero-terminated 2791 ** UTF-8 string. 2792 ** 2793 ** The input to [sqlite3_complete16()] must be a zero-terminated 2794 ** UTF-16 string in native byte order. 2795 */ 2796 SQLITE_API int sqlite3_complete(const char *sql); 2797 SQLITE_API int sqlite3_complete16(const void *sql); 2798 2799 /* 2800 ** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors 2801 ** KEYWORDS: {busy-handler callback} {busy handler} 2802 ** METHOD: sqlite3 2803 ** 2804 ** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X 2805 ** that might be invoked with argument P whenever 2806 ** an attempt is made to access a database table associated with 2807 ** [database connection] D when another thread 2808 ** or process has the table locked. 2809 ** The sqlite3_busy_handler() interface is used to implement 2810 ** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout]. 2811 ** 2812 ** ^If the busy callback is NULL, then [SQLITE_BUSY] 2813 ** is returned immediately upon encountering the lock. ^If the busy callback 2814 ** is not NULL, then the callback might be invoked with two arguments. 2815 ** 2816 ** ^The first argument to the busy handler is a copy of the void* pointer which 2817 ** is the third argument to sqlite3_busy_handler(). ^The second argument to 2818 ** the busy handler callback is the number of times that the busy handler has 2819 ** been invoked previously for the same locking event. ^If the 2820 ** busy callback returns 0, then no additional attempts are made to 2821 ** access the database and [SQLITE_BUSY] is returned 2822 ** to the application. 2823 ** ^If the callback returns non-zero, then another attempt 2824 ** is made to access the database and the cycle repeats. 2825 ** 2826 ** The presence of a busy handler does not guarantee that it will be invoked 2827 ** when there is lock contention. ^If SQLite determines that invoking the busy 2828 ** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY] 2829 ** to the application instead of invoking the 2830 ** busy handler. 2831 ** Consider a scenario where one process is holding a read lock that 2832 ** it is trying to promote to a reserved lock and 2833 ** a second process is holding a reserved lock that it is trying 2834 ** to promote to an exclusive lock. The first process cannot proceed 2835 ** because it is blocked by the second and the second process cannot 2836 ** proceed because it is blocked by the first. If both processes 2837 ** invoke the busy handlers, neither will make any progress. Therefore, 2838 ** SQLite returns [SQLITE_BUSY] for the first process, hoping that this 2839 ** will induce the first process to release its read lock and allow 2840 ** the second process to proceed. 2841 ** 2842 ** ^The default busy callback is NULL. 2843 ** 2844 ** ^(There can only be a single busy handler defined for each 2845 ** [database connection]. Setting a new busy handler clears any 2846 ** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()] 2847 ** or evaluating [PRAGMA busy_timeout=N] will change the 2848 ** busy handler and thus clear any previously set busy handler. 2849 ** 2850 ** The busy callback should not take any actions which modify the 2851 ** database connection that invoked the busy handler. In other words, 2852 ** the busy handler is not reentrant. Any such actions 2853 ** result in undefined behavior. 2854 ** 2855 ** A busy handler must not close the database connection 2856 ** or [prepared statement] that invoked the busy handler. 2857 */ 2858 SQLITE_API int sqlite3_busy_handler(sqlite3*,int(*)(void*,int),void*); 2859 2860 /* 2861 ** CAPI3REF: Set A Busy Timeout 2862 ** METHOD: sqlite3 2863 ** 2864 ** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps 2865 ** for a specified amount of time when a table is locked. ^The handler 2866 ** will sleep multiple times until at least "ms" milliseconds of sleeping 2867 ** have accumulated. ^After at least "ms" milliseconds of sleeping, 2868 ** the handler returns 0 which causes [sqlite3_step()] to return 2869 ** [SQLITE_BUSY]. 2870 ** 2871 ** ^Calling this routine with an argument less than or equal to zero 2872 ** turns off all busy handlers. 2873 ** 2874 ** ^(There can only be a single busy handler for a particular 2875 ** [database connection] at any given moment. If another busy handler 2876 ** was defined (using [sqlite3_busy_handler()]) prior to calling 2877 ** this routine, that other busy handler is cleared.)^ 2878 ** 2879 ** See also: [PRAGMA busy_timeout] 2880 */ 2881 SQLITE_API int sqlite3_busy_timeout(sqlite3*, int ms); 2882 2883 /* 2884 ** CAPI3REF: Convenience Routines For Running Queries 2885 ** METHOD: sqlite3 2886 ** 2887 ** This is a legacy interface that is preserved for backwards compatibility. 2888 ** Use of this interface is not recommended. 2889 ** 2890 ** Definition: A <b>result table</b> is memory data structure created by the 2891 ** [sqlite3_get_table()] interface. A result table records the 2892 ** complete query results from one or more queries. 2893 ** 2894 ** The table conceptually has a number of rows and columns. But 2895 ** these numbers are not part of the result table itself. These 2896 ** numbers are obtained separately. Let N be the number of rows 2897 ** and M be the number of columns. 2898 ** 2899 ** A result table is an array of pointers to zero-terminated UTF-8 strings. 2900 ** There are (N+1)*M elements in the array. The first M pointers point 2901 ** to zero-terminated strings that contain the names of the columns. 2902 ** The remaining entries all point to query results. NULL values result 2903 ** in NULL pointers. All other values are in their UTF-8 zero-terminated 2904 ** string representation as returned by [sqlite3_column_text()]. 2905 ** 2906 ** A result table might consist of one or more memory allocations. 2907 ** It is not safe to pass a result table directly to [sqlite3_free()]. 2908 ** A result table should be deallocated using [sqlite3_free_table()]. 2909 ** 2910 ** ^(As an example of the result table format, suppose a query result 2911 ** is as follows: 2912 ** 2913 ** <blockquote><pre> 2914 ** Name | Age 2915 ** ----------------------- 2916 ** Alice | 43 2917 ** Bob | 28 2918 ** Cindy | 21 2919 ** </pre></blockquote> 2920 ** 2921 ** There are two columns (M==2) and three rows (N==3). Thus the 2922 ** result table has 8 entries. Suppose the result table is stored 2923 ** in an array named azResult. Then azResult holds this content: 2924 ** 2925 ** <blockquote><pre> 2926 ** azResult[0] = "Name"; 2927 ** azResult[1] = "Age"; 2928 ** azResult[2] = "Alice"; 2929 ** azResult[3] = "43"; 2930 ** azResult[4] = "Bob"; 2931 ** azResult[5] = "28"; 2932 ** azResult[6] = "Cindy"; 2933 ** azResult[7] = "21"; 2934 ** </pre></blockquote>)^ 2935 ** 2936 ** ^The sqlite3_get_table() function evaluates one or more 2937 ** semicolon-separated SQL statements in the zero-terminated UTF-8 2938 ** string of its 2nd parameter and returns a result table to the 2939 ** pointer given in its 3rd parameter. 2940 ** 2941 ** After the application has finished with the result from sqlite3_get_table(), 2942 ** it must pass the result table pointer to sqlite3_free_table() in order to 2943 ** release the memory that was malloced. Because of the way the 2944 ** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling 2945 ** function must not try to call [sqlite3_free()] directly. Only 2946 ** [sqlite3_free_table()] is able to release the memory properly and safely. 2947 ** 2948 ** The sqlite3_get_table() interface is implemented as a wrapper around 2949 ** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access 2950 ** to any internal data structures of SQLite. It uses only the public 2951 ** interface defined here. As a consequence, errors that occur in the 2952 ** wrapper layer outside of the internal [sqlite3_exec()] call are not 2953 ** reflected in subsequent calls to [sqlite3_errcode()] or 2954 ** [sqlite3_errmsg()]. 2955 */ 2956 SQLITE_API int sqlite3_get_table( 2957 sqlite3 *db, /* An open database */ 2958 const char *zSql, /* SQL to be evaluated */ 2959 char ***pazResult, /* Results of the query */ 2960 int *pnRow, /* Number of result rows written here */ 2961 int *pnColumn, /* Number of result columns written here */ 2962 char **pzErrmsg /* Error msg written here */ 2963 ); 2964 SQLITE_API void sqlite3_free_table(char **result); 2965 2966 /* 2967 ** CAPI3REF: Formatted String Printing Functions 2968 ** 2969 ** These routines are work-alikes of the "printf()" family of functions 2970 ** from the standard C library. 2971 ** These routines understand most of the common formatting options from 2972 ** the standard library printf() 2973 ** plus some additional non-standard formats ([%q], [%Q], [%w], and [%z]). 2974 ** See the [built-in printf()] documentation for details. 2975 ** 2976 ** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their 2977 ** results into memory obtained from [sqlite3_malloc64()]. 2978 ** The strings returned by these two routines should be 2979 ** released by [sqlite3_free()]. ^Both routines return a 2980 ** NULL pointer if [sqlite3_malloc64()] is unable to allocate enough 2981 ** memory to hold the resulting string. 2982 ** 2983 ** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from 2984 ** the standard C library. The result is written into the 2985 ** buffer supplied as the second parameter whose size is given by 2986 ** the first parameter. Note that the order of the 2987 ** first two parameters is reversed from snprintf().)^ This is an 2988 ** historical accident that cannot be fixed without breaking 2989 ** backwards compatibility. ^(Note also that sqlite3_snprintf() 2990 ** returns a pointer to its buffer instead of the number of 2991 ** characters actually written into the buffer.)^ We admit that 2992 ** the number of characters written would be a more useful return 2993 ** value but we cannot change the implementation of sqlite3_snprintf() 2994 ** now without breaking compatibility. 2995 ** 2996 ** ^As long as the buffer size is greater than zero, sqlite3_snprintf() 2997 ** guarantees that the buffer is always zero-terminated. ^The first 2998 ** parameter "n" is the total size of the buffer, including space for 2999 ** the zero terminator. So the longest string that can be completely 3000 ** written will be n-1 characters. 3001 ** 3002 ** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf(). 3003 ** 3004 ** See also: [built-in printf()], [printf() SQL function] 3005 */ 3006 SQLITE_API char *sqlite3_mprintf(const char*,...); 3007 SQLITE_API char *sqlite3_vmprintf(const char*, va_list); 3008 SQLITE_API char *sqlite3_snprintf(int,char*,const char*, ...); 3009 SQLITE_API char *sqlite3_vsnprintf(int,char*,const char*, va_list); 3010 3011 /* 3012 ** CAPI3REF: Memory Allocation Subsystem 3013 ** 3014 ** The SQLite core uses these three routines for all of its own 3015 ** internal memory allocation needs. "Core" in the previous sentence 3016 ** does not include operating-system specific [VFS] implementation. The 3017 ** Windows VFS uses native malloc() and free() for some operations. 3018 ** 3019 ** ^The sqlite3_malloc() routine returns a pointer to a block 3020 ** of memory at least N bytes in length, where N is the parameter. 3021 ** ^If sqlite3_malloc() is unable to obtain sufficient free 3022 ** memory, it returns a NULL pointer. ^If the parameter N to 3023 ** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns 3024 ** a NULL pointer. 3025 ** 3026 ** ^The sqlite3_malloc64(N) routine works just like 3027 ** sqlite3_malloc(N) except that N is an unsigned 64-bit integer instead 3028 ** of a signed 32-bit integer. 3029 ** 3030 ** ^Calling sqlite3_free() with a pointer previously returned 3031 ** by sqlite3_malloc() or sqlite3_realloc() releases that memory so 3032 ** that it might be reused. ^The sqlite3_free() routine is 3033 ** a no-op if is called with a NULL pointer. Passing a NULL pointer 3034 ** to sqlite3_free() is harmless. After being freed, memory 3035 ** should neither be read nor written. Even reading previously freed 3036 ** memory might result in a segmentation fault or other severe error. 3037 ** Memory corruption, a segmentation fault, or other severe error 3038 ** might result if sqlite3_free() is called with a non-NULL pointer that 3039 ** was not obtained from sqlite3_malloc() or sqlite3_realloc(). 3040 ** 3041 ** ^The sqlite3_realloc(X,N) interface attempts to resize a 3042 ** prior memory allocation X to be at least N bytes. 3043 ** ^If the X parameter to sqlite3_realloc(X,N) 3044 ** is a NULL pointer then its behavior is identical to calling 3045 ** sqlite3_malloc(N). 3046 ** ^If the N parameter to sqlite3_realloc(X,N) is zero or 3047 ** negative then the behavior is exactly the same as calling 3048 ** sqlite3_free(X). 3049 ** ^sqlite3_realloc(X,N) returns a pointer to a memory allocation 3050 ** of at least N bytes in size or NULL if insufficient memory is available. 3051 ** ^If M is the size of the prior allocation, then min(N,M) bytes 3052 ** of the prior allocation are copied into the beginning of buffer returned 3053 ** by sqlite3_realloc(X,N) and the prior allocation is freed. 3054 ** ^If sqlite3_realloc(X,N) returns NULL and N is positive, then the 3055 ** prior allocation is not freed. 3056 ** 3057 ** ^The sqlite3_realloc64(X,N) interfaces works the same as 3058 ** sqlite3_realloc(X,N) except that N is a 64-bit unsigned integer instead 3059 ** of a 32-bit signed integer. 3060 ** 3061 ** ^If X is a memory allocation previously obtained from sqlite3_malloc(), 3062 ** sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then 3063 ** sqlite3_msize(X) returns the size of that memory allocation in bytes. 3064 ** ^The value returned by sqlite3_msize(X) might be larger than the number 3065 ** of bytes requested when X was allocated. ^If X is a NULL pointer then 3066 ** sqlite3_msize(X) returns zero. If X points to something that is not 3067 ** the beginning of memory allocation, or if it points to a formerly 3068 ** valid memory allocation that has now been freed, then the behavior 3069 ** of sqlite3_msize(X) is undefined and possibly harmful. 3070 ** 3071 ** ^The memory returned by sqlite3_malloc(), sqlite3_realloc(), 3072 ** sqlite3_malloc64(), and sqlite3_realloc64() 3073 ** is always aligned to at least an 8 byte boundary, or to a 3074 ** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time 3075 ** option is used. 3076 ** 3077 ** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()] 3078 ** must be either NULL or else pointers obtained from a prior 3079 ** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have 3080 ** not yet been released. 3081 ** 3082 ** The application must not read or write any part of 3083 ** a block of memory after it has been released using 3084 ** [sqlite3_free()] or [sqlite3_realloc()]. 3085 */ 3086 SQLITE_API void *sqlite3_malloc(int); 3087 SQLITE_API void *sqlite3_malloc64(sqlite3_uint64); 3088 SQLITE_API void *sqlite3_realloc(void*, int); 3089 SQLITE_API void *sqlite3_realloc64(void*, sqlite3_uint64); 3090 SQLITE_API void sqlite3_free(void*); 3091 SQLITE_API sqlite3_uint64 sqlite3_msize(void*); 3092 3093 /* 3094 ** CAPI3REF: Memory Allocator Statistics 3095 ** 3096 ** SQLite provides these two interfaces for reporting on the status 3097 ** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()] 3098 ** routines, which form the built-in memory allocation subsystem. 3099 ** 3100 ** ^The [sqlite3_memory_used()] routine returns the number of bytes 3101 ** of memory currently outstanding (malloced but not freed). 3102 ** ^The [sqlite3_memory_highwater()] routine returns the maximum 3103 ** value of [sqlite3_memory_used()] since the high-water mark 3104 ** was last reset. ^The values returned by [sqlite3_memory_used()] and 3105 ** [sqlite3_memory_highwater()] include any overhead 3106 ** added by SQLite in its implementation of [sqlite3_malloc()], 3107 ** but not overhead added by the any underlying system library 3108 ** routines that [sqlite3_malloc()] may call. 3109 ** 3110 ** ^The memory high-water mark is reset to the current value of 3111 ** [sqlite3_memory_used()] if and only if the parameter to 3112 ** [sqlite3_memory_highwater()] is true. ^The value returned 3113 ** by [sqlite3_memory_highwater(1)] is the high-water mark 3114 ** prior to the reset. 3115 */ 3116 SQLITE_API sqlite3_int64 sqlite3_memory_used(void); 3117 SQLITE_API sqlite3_int64 sqlite3_memory_highwater(int resetFlag); 3118 3119 /* 3120 ** CAPI3REF: Pseudo-Random Number Generator 3121 ** 3122 ** SQLite contains a high-quality pseudo-random number generator (PRNG) used to 3123 ** select random [ROWID | ROWIDs] when inserting new records into a table that 3124 ** already uses the largest possible [ROWID]. The PRNG is also used for 3125 ** the built-in random() and randomblob() SQL functions. This interface allows 3126 ** applications to access the same PRNG for other purposes. 3127 ** 3128 ** ^A call to this routine stores N bytes of randomness into buffer P. 3129 ** ^The P parameter can be a NULL pointer. 3130 ** 3131 ** ^If this routine has not been previously called or if the previous 3132 ** call had N less than one or a NULL pointer for P, then the PRNG is 3133 ** seeded using randomness obtained from the xRandomness method of 3134 ** the default [sqlite3_vfs] object. 3135 ** ^If the previous call to this routine had an N of 1 or more and a 3136 ** non-NULL P then the pseudo-randomness is generated 3137 ** internally and without recourse to the [sqlite3_vfs] xRandomness 3138 ** method. 3139 */ 3140 SQLITE_API void sqlite3_randomness(int N, void *P); 3141 3142 /* 3143 ** CAPI3REF: Compile-Time Authorization Callbacks 3144 ** METHOD: sqlite3 3145 ** KEYWORDS: {authorizer callback} 3146 ** 3147 ** ^This routine registers an authorizer callback with a particular 3148 ** [database connection], supplied in the first argument. 3149 ** ^The authorizer callback is invoked as SQL statements are being compiled 3150 ** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()], 3151 ** [sqlite3_prepare_v3()], [sqlite3_prepare16()], [sqlite3_prepare16_v2()], 3152 ** and [sqlite3_prepare16_v3()]. ^At various 3153 ** points during the compilation process, as logic is being created 3154 ** to perform various actions, the authorizer callback is invoked to 3155 ** see if those actions are allowed. ^The authorizer callback should 3156 ** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the 3157 ** specific action but allow the SQL statement to continue to be 3158 ** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be 3159 ** rejected with an error. ^If the authorizer callback returns 3160 ** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY] 3161 ** then the [sqlite3_prepare_v2()] or equivalent call that triggered 3162 ** the authorizer will fail with an error message. 3163 ** 3164 ** When the callback returns [SQLITE_OK], that means the operation 3165 ** requested is ok. ^When the callback returns [SQLITE_DENY], the 3166 ** [sqlite3_prepare_v2()] or equivalent call that triggered the 3167 ** authorizer will fail with an error message explaining that 3168 ** access is denied. 3169 ** 3170 ** ^The first parameter to the authorizer callback is a copy of the third 3171 ** parameter to the sqlite3_set_authorizer() interface. ^The second parameter 3172 ** to the callback is an integer [SQLITE_COPY | action code] that specifies 3173 ** the particular action to be authorized. ^The third through sixth parameters 3174 ** to the callback are either NULL pointers or zero-terminated strings 3175 ** that contain additional details about the action to be authorized. 3176 ** Applications must always be prepared to encounter a NULL pointer in any 3177 ** of the third through the sixth parameters of the authorization callback. 3178 ** 3179 ** ^If the action code is [SQLITE_READ] 3180 ** and the callback returns [SQLITE_IGNORE] then the 3181 ** [prepared statement] statement is constructed to substitute 3182 ** a NULL value in place of the table column that would have 3183 ** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE] 3184 ** return can be used to deny an untrusted user access to individual 3185 ** columns of a table. 3186 ** ^When a table is referenced by a [SELECT] but no column values are 3187 ** extracted from that table (for example in a query like 3188 ** "SELECT count(*) FROM tab") then the [SQLITE_READ] authorizer callback 3189 ** is invoked once for that table with a column name that is an empty string. 3190 ** ^If the action code is [SQLITE_DELETE] and the callback returns 3191 ** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the 3192 ** [truncate optimization] is disabled and all rows are deleted individually. 3193 ** 3194 ** An authorizer is used when [sqlite3_prepare | preparing] 3195 ** SQL statements from an untrusted source, to ensure that the SQL statements 3196 ** do not try to access data they are not allowed to see, or that they do not 3197 ** try to execute malicious statements that damage the database. For 3198 ** example, an application may allow a user to enter arbitrary 3199 ** SQL queries for evaluation by a database. But the application does 3200 ** not want the user to be able to make arbitrary changes to the 3201 ** database. An authorizer could then be put in place while the 3202 ** user-entered SQL is being [sqlite3_prepare | prepared] that 3203 ** disallows everything except [SELECT] statements. 3204 ** 3205 ** Applications that need to process SQL from untrusted sources 3206 ** might also consider lowering resource limits using [sqlite3_limit()] 3207 ** and limiting database size using the [max_page_count] [PRAGMA] 3208 ** in addition to using an authorizer. 3209 ** 3210 ** ^(Only a single authorizer can be in place on a database connection 3211 ** at a time. Each call to sqlite3_set_authorizer overrides the 3212 ** previous call.)^ ^Disable the authorizer by installing a NULL callback. 3213 ** The authorizer is disabled by default. 3214 ** 3215 ** The authorizer callback must not do anything that will modify 3216 ** the database connection that invoked the authorizer callback. 3217 ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their 3218 ** database connections for the meaning of "modify" in this paragraph. 3219 ** 3220 ** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the 3221 ** statement might be re-prepared during [sqlite3_step()] due to a 3222 ** schema change. Hence, the application should ensure that the 3223 ** correct authorizer callback remains in place during the [sqlite3_step()]. 3224 ** 3225 ** ^Note that the authorizer callback is invoked only during 3226 ** [sqlite3_prepare()] or its variants. Authorization is not 3227 ** performed during statement evaluation in [sqlite3_step()], unless 3228 ** as stated in the previous paragraph, sqlite3_step() invokes 3229 ** sqlite3_prepare_v2() to reprepare a statement after a schema change. 3230 */ 3231 SQLITE_API int sqlite3_set_authorizer( 3232 sqlite3*, 3233 int (*xAuth)(void*,int,const char*,const char*,const char*,const char*), 3234 void *pUserData 3235 ); 3236 3237 /* 3238 ** CAPI3REF: Authorizer Return Codes 3239 ** 3240 ** The [sqlite3_set_authorizer | authorizer callback function] must 3241 ** return either [SQLITE_OK] or one of these two constants in order 3242 ** to signal SQLite whether or not the action is permitted. See the 3243 ** [sqlite3_set_authorizer | authorizer documentation] for additional 3244 ** information. 3245 ** 3246 ** Note that SQLITE_IGNORE is also used as a [conflict resolution mode] 3247 ** returned from the [sqlite3_vtab_on_conflict()] interface. 3248 */ 3249 #define SQLITE_DENY 1 /* Abort the SQL statement with an error */ 3250 #define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error */ 3251 3252 /* 3253 ** CAPI3REF: Authorizer Action Codes 3254 ** 3255 ** The [sqlite3_set_authorizer()] interface registers a callback function 3256 ** that is invoked to authorize certain SQL statement actions. The 3257 ** second parameter to the callback is an integer code that specifies 3258 ** what action is being authorized. These are the integer action codes that 3259 ** the authorizer callback may be passed. 3260 ** 3261 ** These action code values signify what kind of operation is to be 3262 ** authorized. The 3rd and 4th parameters to the authorization 3263 ** callback function will be parameters or NULL depending on which of these 3264 ** codes is used as the second parameter. ^(The 5th parameter to the 3265 ** authorizer callback is the name of the database ("main", "temp", 3266 ** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback 3267 ** is the name of the inner-most trigger or view that is responsible for 3268 ** the access attempt or NULL if this access attempt is directly from 3269 ** top-level SQL code. 3270 */ 3271 /******************************************* 3rd ************ 4th ***********/ 3272 #define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */ 3273 #define SQLITE_CREATE_TABLE 2 /* Table Name NULL */ 3274 #define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */ 3275 #define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */ 3276 #define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */ 3277 #define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */ 3278 #define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */ 3279 #define SQLITE_CREATE_VIEW 8 /* View Name NULL */ 3280 #define SQLITE_DELETE 9 /* Table Name NULL */ 3281 #define SQLITE_DROP_INDEX 10 /* Index Name Table Name */ 3282 #define SQLITE_DROP_TABLE 11 /* Table Name NULL */ 3283 #define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */ 3284 #define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */ 3285 #define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */ 3286 #define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */ 3287 #define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */ 3288 #define SQLITE_DROP_VIEW 17 /* View Name NULL */ 3289 #define SQLITE_INSERT 18 /* Table Name NULL */ 3290 #define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */ 3291 #define SQLITE_READ 20 /* Table Name Column Name */ 3292 #define SQLITE_SELECT 21 /* NULL NULL */ 3293 #define SQLITE_TRANSACTION 22 /* Operation NULL */ 3294 #define SQLITE_UPDATE 23 /* Table Name Column Name */ 3295 #define SQLITE_ATTACH 24 /* Filename NULL */ 3296 #define SQLITE_DETACH 25 /* Database Name NULL */ 3297 #define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */ 3298 #define SQLITE_REINDEX 27 /* Index Name NULL */ 3299 #define SQLITE_ANALYZE 28 /* Table Name NULL */ 3300 #define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */ 3301 #define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */ 3302 #define SQLITE_FUNCTION 31 /* NULL Function Name */ 3303 #define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */ 3304 #define SQLITE_COPY 0 /* No longer used */ 3305 #define SQLITE_RECURSIVE 33 /* NULL NULL */ 3306 3307 /* 3308 ** CAPI3REF: Deprecated Tracing And Profiling Functions 3309 ** DEPRECATED 3310 ** 3311 ** These routines are deprecated. Use the [sqlite3_trace_v2()] interface 3312 ** instead of the routines described here. 3313 ** 3314 ** These routines register callback functions that can be used for 3315 ** tracing and profiling the execution of SQL statements. 3316 ** 3317 ** ^The callback function registered by sqlite3_trace() is invoked at 3318 ** various times when an SQL statement is being run by [sqlite3_step()]. 3319 ** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the 3320 ** SQL statement text as the statement first begins executing. 3321 ** ^(Additional sqlite3_trace() callbacks might occur 3322 ** as each triggered subprogram is entered. The callbacks for triggers 3323 ** contain a UTF-8 SQL comment that identifies the trigger.)^ 3324 ** 3325 ** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit 3326 ** the length of [bound parameter] expansion in the output of sqlite3_trace(). 3327 ** 3328 ** ^The callback function registered by sqlite3_profile() is invoked 3329 ** as each SQL statement finishes. ^The profile callback contains 3330 ** the original statement text and an estimate of wall-clock time 3331 ** of how long that statement took to run. ^The profile callback 3332 ** time is in units of nanoseconds, however the current implementation 3333 ** is only capable of millisecond resolution so the six least significant 3334 ** digits in the time are meaningless. Future versions of SQLite 3335 ** might provide greater resolution on the profiler callback. Invoking 3336 ** either [sqlite3_trace()] or [sqlite3_trace_v2()] will cancel the 3337 ** profile callback. 3338 */ 3339 SQLITE_API SQLITE_DEPRECATED void *sqlite3_trace(sqlite3*, 3340 void(*xTrace)(void*,const char*), void*); 3341 SQLITE_API SQLITE_DEPRECATED void *sqlite3_profile(sqlite3*, 3342 void(*xProfile)(void*,const char*,sqlite3_uint64), void*); 3343 3344 /* 3345 ** CAPI3REF: SQL Trace Event Codes 3346 ** KEYWORDS: SQLITE_TRACE 3347 ** 3348 ** These constants identify classes of events that can be monitored 3349 ** using the [sqlite3_trace_v2()] tracing logic. The M argument 3350 ** to [sqlite3_trace_v2(D,M,X,P)] is an OR-ed combination of one or more of 3351 ** the following constants. ^The first argument to the trace callback 3352 ** is one of the following constants. 3353 ** 3354 ** New tracing constants may be added in future releases. 3355 ** 3356 ** ^A trace callback has four arguments: xCallback(T,C,P,X). 3357 ** ^The T argument is one of the integer type codes above. 3358 ** ^The C argument is a copy of the context pointer passed in as the 3359 ** fourth argument to [sqlite3_trace_v2()]. 3360 ** The P and X arguments are pointers whose meanings depend on T. 3361 ** 3362 ** <dl> 3363 ** [[SQLITE_TRACE_STMT]] <dt>SQLITE_TRACE_STMT</dt> 3364 ** <dd>^An SQLITE_TRACE_STMT callback is invoked when a prepared statement 3365 ** first begins running and possibly at other times during the 3366 ** execution of the prepared statement, such as at the start of each 3367 ** trigger subprogram. ^The P argument is a pointer to the 3368 ** [prepared statement]. ^The X argument is a pointer to a string which 3369 ** is the unexpanded SQL text of the prepared statement or an SQL comment 3370 ** that indicates the invocation of a trigger. ^The callback can compute 3371 ** the same text that would have been returned by the legacy [sqlite3_trace()] 3372 ** interface by using the X argument when X begins with "--" and invoking 3373 ** [sqlite3_expanded_sql(P)] otherwise. 3374 ** 3375 ** [[SQLITE_TRACE_PROFILE]] <dt>SQLITE_TRACE_PROFILE</dt> 3376 ** <dd>^An SQLITE_TRACE_PROFILE callback provides approximately the same 3377 ** information as is provided by the [sqlite3_profile()] callback. 3378 ** ^The P argument is a pointer to the [prepared statement] and the 3379 ** X argument points to a 64-bit integer which is approximately 3380 ** the number of nanoseconds that the prepared statement took to run. 3381 ** ^The SQLITE_TRACE_PROFILE callback is invoked when the statement finishes. 3382 ** 3383 ** [[SQLITE_TRACE_ROW]] <dt>SQLITE_TRACE_ROW</dt> 3384 ** <dd>^An SQLITE_TRACE_ROW callback is invoked whenever a prepared 3385 ** statement generates a single row of result. 3386 ** ^The P argument is a pointer to the [prepared statement] and the 3387 ** X argument is unused. 3388 ** 3389 ** [[SQLITE_TRACE_CLOSE]] <dt>SQLITE_TRACE_CLOSE</dt> 3390 ** <dd>^An SQLITE_TRACE_CLOSE callback is invoked when a database 3391 ** connection closes. 3392 ** ^The P argument is a pointer to the [database connection] object 3393 ** and the X argument is unused. 3394 ** </dl> 3395 */ 3396 #define SQLITE_TRACE_STMT 0x01 3397 #define SQLITE_TRACE_PROFILE 0x02 3398 #define SQLITE_TRACE_ROW 0x04 3399 #define SQLITE_TRACE_CLOSE 0x08 3400 3401 /* 3402 ** CAPI3REF: SQL Trace Hook 3403 ** METHOD: sqlite3 3404 ** 3405 ** ^The sqlite3_trace_v2(D,M,X,P) interface registers a trace callback 3406 ** function X against [database connection] D, using property mask M 3407 ** and context pointer P. ^If the X callback is 3408 ** NULL or if the M mask is zero, then tracing is disabled. The 3409 ** M argument should be the bitwise OR-ed combination of 3410 ** zero or more [SQLITE_TRACE] constants. 3411 ** 3412 ** ^Each call to either sqlite3_trace(D,X,P) or sqlite3_trace_v2(D,M,X,P) 3413 ** overrides (cancels) all prior calls to sqlite3_trace(D,X,P) or 3414 ** sqlite3_trace_v2(D,M,X,P) for the [database connection] D. Each 3415 ** database connection may have at most one trace callback. 3416 ** 3417 ** ^The X callback is invoked whenever any of the events identified by 3418 ** mask M occur. ^The integer return value from the callback is currently 3419 ** ignored, though this may change in future releases. Callback 3420 ** implementations should return zero to ensure future compatibility. 3421 ** 3422 ** ^A trace callback is invoked with four arguments: callback(T,C,P,X). 3423 ** ^The T argument is one of the [SQLITE_TRACE] 3424 ** constants to indicate why the callback was invoked. 3425 ** ^The C argument is a copy of the context pointer. 3426 ** The P and X arguments are pointers whose meanings depend on T. 3427 ** 3428 ** The sqlite3_trace_v2() interface is intended to replace the legacy 3429 ** interfaces [sqlite3_trace()] and [sqlite3_profile()], both of which 3430 ** are deprecated. 3431 */ 3432 SQLITE_API int sqlite3_trace_v2( 3433 sqlite3*, 3434 unsigned uMask, 3435 int(*xCallback)(unsigned,void*,void*,void*), 3436 void *pCtx 3437 ); 3438 3439 /* 3440 ** CAPI3REF: Query Progress Callbacks 3441 ** METHOD: sqlite3 3442 ** 3443 ** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback 3444 ** function X to be invoked periodically during long running calls to 3445 ** [sqlite3_step()] and [sqlite3_prepare()] and similar for 3446 ** database connection D. An example use for this 3447 ** interface is to keep a GUI updated during a large query. 3448 ** 3449 ** ^The parameter P is passed through as the only parameter to the 3450 ** callback function X. ^The parameter N is the approximate number of 3451 ** [virtual machine instructions] that are evaluated between successive 3452 ** invocations of the callback X. ^If N is less than one then the progress 3453 ** handler is disabled. 3454 ** 3455 ** ^Only a single progress handler may be defined at one time per 3456 ** [database connection]; setting a new progress handler cancels the 3457 ** old one. ^Setting parameter X to NULL disables the progress handler. 3458 ** ^The progress handler is also disabled by setting N to a value less 3459 ** than 1. 3460 ** 3461 ** ^If the progress callback returns non-zero, the operation is 3462 ** interrupted. This feature can be used to implement a 3463 ** "Cancel" button on a GUI progress dialog box. 3464 ** 3465 ** The progress handler callback must not do anything that will modify 3466 ** the database connection that invoked the progress handler. 3467 ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their 3468 ** database connections for the meaning of "modify" in this paragraph. 3469 ** 3470 ** The progress handler callback would originally only be invoked from the 3471 ** bytecode engine. It still might be invoked during [sqlite3_prepare()] 3472 ** and similar because those routines might force a reparse of the schema 3473 ** which involves running the bytecode engine. However, beginning with 3474 ** SQLite version 3.41.0, the progress handler callback might also be 3475 ** invoked directly from [sqlite3_prepare()] while analyzing and generating 3476 ** code for complex queries. 3477 */ 3478 SQLITE_API void sqlite3_progress_handler(sqlite3*, int, int(*)(void*), void*); 3479 3480 /* 3481 ** CAPI3REF: Opening A New Database Connection 3482 ** CONSTRUCTOR: sqlite3 3483 ** 3484 ** ^These routines open an SQLite database file as specified by the 3485 ** filename argument. ^The filename argument is interpreted as UTF-8 for 3486 ** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte 3487 ** order for sqlite3_open16(). ^(A [database connection] handle is usually 3488 ** returned in *ppDb, even if an error occurs. The only exception is that 3489 ** if SQLite is unable to allocate memory to hold the [sqlite3] object, 3490 ** a NULL will be written into *ppDb instead of a pointer to the [sqlite3] 3491 ** object.)^ ^(If the database is opened (and/or created) successfully, then 3492 ** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The 3493 ** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain 3494 ** an English language description of the error following a failure of any 3495 ** of the sqlite3_open() routines. 3496 ** 3497 ** ^The default encoding will be UTF-8 for databases created using 3498 ** sqlite3_open() or sqlite3_open_v2(). ^The default encoding for databases 3499 ** created using sqlite3_open16() will be UTF-16 in the native byte order. 3500 ** 3501 ** Whether or not an error occurs when it is opened, resources 3502 ** associated with the [database connection] handle should be released by 3503 ** passing it to [sqlite3_close()] when it is no longer required. 3504 ** 3505 ** The sqlite3_open_v2() interface works like sqlite3_open() 3506 ** except that it accepts two additional parameters for additional control 3507 ** over the new database connection. ^(The flags parameter to 3508 ** sqlite3_open_v2() must include, at a minimum, one of the following 3509 ** three flag combinations:)^ 3510 ** 3511 ** <dl> 3512 ** ^(<dt>[SQLITE_OPEN_READONLY]</dt> 3513 ** <dd>The database is opened in read-only mode. If the database does 3514 ** not already exist, an error is returned.</dd>)^ 3515 ** 3516 ** ^(<dt>[SQLITE_OPEN_READWRITE]</dt> 3517 ** <dd>The database is opened for reading and writing if possible, or 3518 ** reading only if the file is write protected by the operating 3519 ** system. In either case the database must already exist, otherwise 3520 ** an error is returned. For historical reasons, if opening in 3521 ** read-write mode fails due to OS-level permissions, an attempt is 3522 ** made to open it in read-only mode. [sqlite3_db_readonly()] can be 3523 ** used to determine whether the database is actually 3524 ** read-write.</dd>)^ 3525 ** 3526 ** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt> 3527 ** <dd>The database is opened for reading and writing, and is created if 3528 ** it does not already exist. This is the behavior that is always used for 3529 ** sqlite3_open() and sqlite3_open16().</dd>)^ 3530 ** </dl> 3531 ** 3532 ** In addition to the required flags, the following optional flags are 3533 ** also supported: 3534 ** 3535 ** <dl> 3536 ** ^(<dt>[SQLITE_OPEN_URI]</dt> 3537 ** <dd>The filename can be interpreted as a URI if this flag is set.</dd>)^ 3538 ** 3539 ** ^(<dt>[SQLITE_OPEN_MEMORY]</dt> 3540 ** <dd>The database will be opened as an in-memory database. The database 3541 ** is named by the "filename" argument for the purposes of cache-sharing, 3542 ** if shared cache mode is enabled, but the "filename" is otherwise ignored. 3543 ** </dd>)^ 3544 ** 3545 ** ^(<dt>[SQLITE_OPEN_NOMUTEX]</dt> 3546 ** <dd>The new database connection will use the "multi-thread" 3547 ** [threading mode].)^ This means that separate threads are allowed 3548 ** to use SQLite at the same time, as long as each thread is using 3549 ** a different [database connection]. 3550 ** 3551 ** ^(<dt>[SQLITE_OPEN_FULLMUTEX]</dt> 3552 ** <dd>The new database connection will use the "serialized" 3553 ** [threading mode].)^ This means the multiple threads can safely 3554 ** attempt to use the same database connection at the same time. 3555 ** (Mutexes will block any actual concurrency, but in this mode 3556 ** there is no harm in trying.) 3557 ** 3558 ** ^(<dt>[SQLITE_OPEN_SHAREDCACHE]</dt> 3559 ** <dd>The database is opened [shared cache] enabled, overriding 3560 ** the default shared cache setting provided by 3561 ** [sqlite3_enable_shared_cache()].)^ 3562 ** The [use of shared cache mode is discouraged] and hence shared cache 3563 ** capabilities may be omitted from many builds of SQLite. In such cases, 3564 ** this option is a no-op. 3565 ** 3566 ** ^(<dt>[SQLITE_OPEN_PRIVATECACHE]</dt> 3567 ** <dd>The database is opened [shared cache] disabled, overriding 3568 ** the default shared cache setting provided by 3569 ** [sqlite3_enable_shared_cache()].)^ 3570 ** 3571 ** [[OPEN_EXRESCODE]] ^(<dt>[SQLITE_OPEN_EXRESCODE]</dt> 3572 ** <dd>The database connection comes up in "extended result code mode". 3573 ** In other words, the database behaves has if 3574 ** [sqlite3_extended_result_codes(db,1)] where called on the database 3575 ** connection as soon as the connection is created. In addition to setting 3576 ** the extended result code mode, this flag also causes [sqlite3_open_v2()] 3577 ** to return an extended result code.</dd> 3578 ** 3579 ** [[OPEN_NOFOLLOW]] ^(<dt>[SQLITE_OPEN_NOFOLLOW]</dt> 3580 ** <dd>The database filename is not allowed to contain a symbolic link</dd> 3581 ** </dl>)^ 3582 ** 3583 ** If the 3rd parameter to sqlite3_open_v2() is not one of the 3584 ** required combinations shown above optionally combined with other 3585 ** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits] 3586 ** then the behavior is undefined. Historic versions of SQLite 3587 ** have silently ignored surplus bits in the flags parameter to 3588 ** sqlite3_open_v2(), however that behavior might not be carried through 3589 ** into future versions of SQLite and so applications should not rely 3590 ** upon it. Note in particular that the SQLITE_OPEN_EXCLUSIVE flag is a no-op 3591 ** for sqlite3_open_v2(). The SQLITE_OPEN_EXCLUSIVE does *not* cause 3592 ** the open to fail if the database already exists. The SQLITE_OPEN_EXCLUSIVE 3593 ** flag is intended for use by the [sqlite3_vfs|VFS interface] only, and not 3594 ** by sqlite3_open_v2(). 3595 ** 3596 ** ^The fourth parameter to sqlite3_open_v2() is the name of the 3597 ** [sqlite3_vfs] object that defines the operating system interface that 3598 ** the new database connection should use. ^If the fourth parameter is 3599 ** a NULL pointer then the default [sqlite3_vfs] object is used. 3600 ** 3601 ** ^If the filename is ":memory:", then a private, temporary in-memory database 3602 ** is created for the connection. ^This in-memory database will vanish when 3603 ** the database connection is closed. Future versions of SQLite might 3604 ** make use of additional special filenames that begin with the ":" character. 3605 ** It is recommended that when a database filename actually does begin with 3606 ** a ":" character you should prefix the filename with a pathname such as 3607 ** "./" to avoid ambiguity. 3608 ** 3609 ** ^If the filename is an empty string, then a private, temporary 3610 ** on-disk database will be created. ^This private database will be 3611 ** automatically deleted as soon as the database connection is closed. 3612 ** 3613 ** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3> 3614 ** 3615 ** ^If [URI filename] interpretation is enabled, and the filename argument 3616 ** begins with "file:", then the filename is interpreted as a URI. ^URI 3617 ** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is 3618 ** set in the third argument to sqlite3_open_v2(), or if it has 3619 ** been enabled globally using the [SQLITE_CONFIG_URI] option with the 3620 ** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option. 3621 ** URI filename interpretation is turned off 3622 ** by default, but future releases of SQLite might enable URI filename 3623 ** interpretation by default. See "[URI filenames]" for additional 3624 ** information. 3625 ** 3626 ** URI filenames are parsed according to RFC 3986. ^If the URI contains an 3627 ** authority, then it must be either an empty string or the string 3628 ** "localhost". ^If the authority is not an empty string or "localhost", an 3629 ** error is returned to the caller. ^The fragment component of a URI, if 3630 ** present, is ignored. 3631 ** 3632 ** ^SQLite uses the path component of the URI as the name of the disk file 3633 ** which contains the database. ^If the path begins with a '/' character, 3634 ** then it is interpreted as an absolute path. ^If the path does not begin 3635 ** with a '/' (meaning that the authority section is omitted from the URI) 3636 ** then the path is interpreted as a relative path. 3637 ** ^(On windows, the first component of an absolute path 3638 ** is a drive specification (e.g. "C:").)^ 3639 ** 3640 ** [[core URI query parameters]] 3641 ** The query component of a URI may contain parameters that are interpreted 3642 ** either by SQLite itself, or by a [VFS | custom VFS implementation]. 3643 ** SQLite and its built-in [VFSes] interpret the 3644 ** following query parameters: 3645 ** 3646 ** <ul> 3647 ** <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of 3648 ** a VFS object that provides the operating system interface that should 3649 ** be used to access the database file on disk. ^If this option is set to 3650 ** an empty string the default VFS object is used. ^Specifying an unknown 3651 ** VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is 3652 ** present, then the VFS specified by the option takes precedence over 3653 ** the value passed as the fourth parameter to sqlite3_open_v2(). 3654 ** 3655 ** <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw", 3656 ** "rwc", or "memory". Attempting to set it to any other value is 3657 ** an error)^. 3658 ** ^If "ro" is specified, then the database is opened for read-only 3659 ** access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the 3660 ** third argument to sqlite3_open_v2(). ^If the mode option is set to 3661 ** "rw", then the database is opened for read-write (but not create) 3662 ** access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had 3663 ** been set. ^Value "rwc" is equivalent to setting both 3664 ** SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE. ^If the mode option is 3665 ** set to "memory" then a pure [in-memory database] that never reads 3666 ** or writes from disk is used. ^It is an error to specify a value for 3667 ** the mode parameter that is less restrictive than that specified by 3668 ** the flags passed in the third parameter to sqlite3_open_v2(). 3669 ** 3670 ** <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or 3671 ** "private". ^Setting it to "shared" is equivalent to setting the 3672 ** SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to 3673 ** sqlite3_open_v2(). ^Setting the cache parameter to "private" is 3674 ** equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit. 3675 ** ^If sqlite3_open_v2() is used and the "cache" parameter is present in 3676 ** a URI filename, its value overrides any behavior requested by setting 3677 ** SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag. 3678 ** 3679 ** <li> <b>psow</b>: ^The psow parameter indicates whether or not the 3680 ** [powersafe overwrite] property does or does not apply to the 3681 ** storage media on which the database file resides. 3682 ** 3683 ** <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter 3684 ** which if set disables file locking in rollback journal modes. This 3685 ** is useful for accessing a database on a filesystem that does not 3686 ** support locking. Caution: Database corruption might result if two 3687 ** or more processes write to the same database and any one of those 3688 ** processes uses nolock=1. 3689 ** 3690 ** <li> <b>immutable</b>: ^The immutable parameter is a boolean query 3691 ** parameter that indicates that the database file is stored on 3692 ** read-only media. ^When immutable is set, SQLite assumes that the 3693 ** database file cannot be changed, even by a process with higher 3694 ** privilege, and so the database is opened read-only and all locking 3695 ** and change detection is disabled. Caution: Setting the immutable 3696 ** property on a database file that does in fact change can result 3697 ** in incorrect query results and/or [SQLITE_CORRUPT] errors. 3698 ** See also: [SQLITE_IOCAP_IMMUTABLE]. 3699 ** 3700 ** </ul> 3701 ** 3702 ** ^Specifying an unknown parameter in the query component of a URI is not an 3703 ** error. Future versions of SQLite might understand additional query 3704 ** parameters. See "[query parameters with special meaning to SQLite]" for 3705 ** additional information. 3706 ** 3707 ** [[URI filename examples]] <h3>URI filename examples</h3> 3708 ** 3709 ** <table border="1" align=center cellpadding=5> 3710 ** <tr><th> URI filenames <th> Results 3711 ** <tr><td> file:data.db <td> 3712 ** Open the file "data.db" in the current directory. 3713 ** <tr><td> file:/home/fred/data.db<br> 3714 ** file:///home/fred/data.db <br> 3715 ** file://localhost/home/fred/data.db <br> <td> 3716 ** Open the database file "/home/fred/data.db". 3717 ** <tr><td> file://darkstar/home/fred/data.db <td> 3718 ** An error. "darkstar" is not a recognized authority. 3719 ** <tr><td style="white-space:nowrap"> 3720 ** file:///C:/Documents%20and%20Settings/fred/Desktop/data.db 3721 ** <td> Windows only: Open the file "data.db" on fred's desktop on drive 3722 ** C:. Note that the %20 escaping in this example is not strictly 3723 ** necessary - space characters can be used literally 3724 ** in URI filenames. 3725 ** <tr><td> file:data.db?mode=ro&cache=private <td> 3726 ** Open file "data.db" in the current directory for read-only access. 3727 ** Regardless of whether or not shared-cache mode is enabled by 3728 ** default, use a private cache. 3729 ** <tr><td> file:/home/fred/data.db?vfs=unix-dotfile <td> 3730 ** Open file "/home/fred/data.db". Use the special VFS "unix-dotfile" 3731 ** that uses dot-files in place of posix advisory locking. 3732 ** <tr><td> file:data.db?mode=readonly <td> 3733 ** An error. "readonly" is not a valid option for the "mode" parameter. 3734 ** Use "ro" instead: "file:data.db?mode=ro". 3735 ** </table> 3736 ** 3737 ** ^URI hexadecimal escape sequences (%HH) are supported within the path and 3738 ** query components of a URI. A hexadecimal escape sequence consists of a 3739 ** percent sign - "%" - followed by exactly two hexadecimal digits 3740 ** specifying an octet value. ^Before the path or query components of a 3741 ** URI filename are interpreted, they are encoded using UTF-8 and all 3742 ** hexadecimal escape sequences replaced by a single byte containing the 3743 ** corresponding octet. If this process generates an invalid UTF-8 encoding, 3744 ** the results are undefined. 3745 ** 3746 ** <b>Note to Windows users:</b> The encoding used for the filename argument 3747 ** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever 3748 ** codepage is currently defined. Filenames containing international 3749 ** characters must be converted to UTF-8 prior to passing them into 3750 ** sqlite3_open() or sqlite3_open_v2(). 3751 ** 3752 ** <b>Note to Windows Runtime users:</b> The temporary directory must be set 3753 ** prior to calling sqlite3_open() or sqlite3_open_v2(). Otherwise, various 3754 ** features that require the use of temporary files may fail. 3755 ** 3756 ** See also: [sqlite3_temp_directory] 3757 */ 3758 SQLITE_API int sqlite3_open( 3759 const char *filename, /* Database filename (UTF-8) */ 3760 sqlite3 **ppDb /* OUT: SQLite db handle */ 3761 ); 3762 SQLITE_API int sqlite3_open16( 3763 const void *filename, /* Database filename (UTF-16) */ 3764 sqlite3 **ppDb /* OUT: SQLite db handle */ 3765 ); 3766 SQLITE_API int sqlite3_open_v2( 3767 const char *filename, /* Database filename (UTF-8) */ 3768 sqlite3 **ppDb, /* OUT: SQLite db handle */ 3769 int flags, /* Flags */ 3770 const char *zVfs /* Name of VFS module to use */ 3771 ); 3772 3773 /* 3774 ** CAPI3REF: Obtain Values For URI Parameters 3775 ** 3776 ** These are utility routines, useful to [VFS|custom VFS implementations], 3777 ** that check if a database file was a URI that contained a specific query 3778 ** parameter, and if so obtains the value of that query parameter. 3779 ** 3780 ** The first parameter to these interfaces (hereafter referred to 3781 ** as F) must be one of: 3782 ** <ul> 3783 ** <li> A database filename pointer created by the SQLite core and 3784 ** passed into the xOpen() method of a VFS implementation, or 3785 ** <li> A filename obtained from [sqlite3_db_filename()], or 3786 ** <li> A new filename constructed using [sqlite3_create_filename()]. 3787 ** </ul> 3788 ** If the F parameter is not one of the above, then the behavior is 3789 ** undefined and probably undesirable. Older versions of SQLite were 3790 ** more tolerant of invalid F parameters than newer versions. 3791 ** 3792 ** If F is a suitable filename (as described in the previous paragraph) 3793 ** and if P is the name of the query parameter, then 3794 ** sqlite3_uri_parameter(F,P) returns the value of the P 3795 ** parameter if it exists or a NULL pointer if P does not appear as a 3796 ** query parameter on F. If P is a query parameter of F and it 3797 ** has no explicit value, then sqlite3_uri_parameter(F,P) returns 3798 ** a pointer to an empty string. 3799 ** 3800 ** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean 3801 ** parameter and returns true (1) or false (0) according to the value 3802 ** of P. The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the 3803 ** value of query parameter P is one of "yes", "true", or "on" in any 3804 ** case or if the value begins with a non-zero number. The 3805 ** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of 3806 ** query parameter P is one of "no", "false", or "off" in any case or 3807 ** if the value begins with a numeric zero. If P is not a query 3808 ** parameter on F or if the value of P does not match any of the 3809 ** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0). 3810 ** 3811 ** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a 3812 ** 64-bit signed integer and returns that integer, or D if P does not 3813 ** exist. If the value of P is something other than an integer, then 3814 ** zero is returned. 3815 ** 3816 ** The sqlite3_uri_key(F,N) returns a pointer to the name (not 3817 ** the value) of the N-th query parameter for filename F, or a NULL 3818 ** pointer if N is less than zero or greater than the number of query 3819 ** parameters minus 1. The N value is zero-based so N should be 0 to obtain 3820 ** the name of the first query parameter, 1 for the second parameter, and 3821 ** so forth. 3822 ** 3823 ** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and 3824 ** sqlite3_uri_boolean(F,P,B) returns B. If F is not a NULL pointer and 3825 ** is not a database file pathname pointer that the SQLite core passed 3826 ** into the xOpen VFS method, then the behavior of this routine is undefined 3827 ** and probably undesirable. 3828 ** 3829 ** Beginning with SQLite [version 3.31.0] ([dateof:3.31.0]) the input F 3830 ** parameter can also be the name of a rollback journal file or WAL file 3831 ** in addition to the main database file. Prior to version 3.31.0, these 3832 ** routines would only work if F was the name of the main database file. 3833 ** When the F parameter is the name of the rollback journal or WAL file, 3834 ** it has access to all the same query parameters as were found on the 3835 ** main database file. 3836 ** 3837 ** See the [URI filename] documentation for additional information. 3838 */ 3839 SQLITE_API const char *sqlite3_uri_parameter(sqlite3_filename z, const char *zParam); 3840 SQLITE_API int sqlite3_uri_boolean(sqlite3_filename z, const char *zParam, int bDefault); 3841 SQLITE_API sqlite3_int64 sqlite3_uri_int64(sqlite3_filename, const char*, sqlite3_int64); 3842 SQLITE_API const char *sqlite3_uri_key(sqlite3_filename z, int N); 3843 3844 /* 3845 ** CAPI3REF: Translate filenames 3846 ** 3847 ** These routines are available to [VFS|custom VFS implementations] for 3848 ** translating filenames between the main database file, the journal file, 3849 ** and the WAL file. 3850 ** 3851 ** If F is the name of an sqlite database file, journal file, or WAL file 3852 ** passed by the SQLite core into the VFS, then sqlite3_filename_database(F) 3853 ** returns the name of the corresponding database file. 3854 ** 3855 ** If F is the name of an sqlite database file, journal file, or WAL file 3856 ** passed by the SQLite core into the VFS, or if F is a database filename 3857 ** obtained from [sqlite3_db_filename()], then sqlite3_filename_journal(F) 3858 ** returns the name of the corresponding rollback journal file. 3859 ** 3860 ** If F is the name of an sqlite database file, journal file, or WAL file 3861 ** that was passed by the SQLite core into the VFS, or if F is a database 3862 ** filename obtained from [sqlite3_db_filename()], then 3863 ** sqlite3_filename_wal(F) returns the name of the corresponding 3864 ** WAL file. 3865 ** 3866 ** In all of the above, if F is not the name of a database, journal or WAL 3867 ** filename passed into the VFS from the SQLite core and F is not the 3868 ** return value from [sqlite3_db_filename()], then the result is 3869 ** undefined and is likely a memory access violation. 3870 */ 3871 SQLITE_API const char *sqlite3_filename_database(sqlite3_filename); 3872 SQLITE_API const char *sqlite3_filename_journal(sqlite3_filename); 3873 SQLITE_API const char *sqlite3_filename_wal(sqlite3_filename); 3874 3875 /* 3876 ** CAPI3REF: Database File Corresponding To A Journal 3877 ** 3878 ** ^If X is the name of a rollback or WAL-mode journal file that is 3879 ** passed into the xOpen method of [sqlite3_vfs], then 3880 ** sqlite3_database_file_object(X) returns a pointer to the [sqlite3_file] 3881 ** object that represents the main database file. 3882 ** 3883 ** This routine is intended for use in custom [VFS] implementations 3884 ** only. It is not a general-purpose interface. 3885 ** The argument sqlite3_file_object(X) must be a filename pointer that 3886 ** has been passed into [sqlite3_vfs].xOpen method where the 3887 ** flags parameter to xOpen contains one of the bits 3888 ** [SQLITE_OPEN_MAIN_JOURNAL] or [SQLITE_OPEN_WAL]. Any other use 3889 ** of this routine results in undefined and probably undesirable 3890 ** behavior. 3891 */ 3892 SQLITE_API sqlite3_file *sqlite3_database_file_object(const char*); 3893 3894 /* 3895 ** CAPI3REF: Create and Destroy VFS Filenames 3896 ** 3897 ** These interfaces are provided for use by [VFS shim] implementations and 3898 ** are not useful outside of that context. 3899 ** 3900 ** The sqlite3_create_filename(D,J,W,N,P) allocates memory to hold a version of 3901 ** database filename D with corresponding journal file J and WAL file W and 3902 ** with N URI parameters key/values pairs in the array P. The result from 3903 ** sqlite3_create_filename(D,J,W,N,P) is a pointer to a database filename that 3904 ** is safe to pass to routines like: 3905 ** <ul> 3906 ** <li> [sqlite3_uri_parameter()], 3907 ** <li> [sqlite3_uri_boolean()], 3908 ** <li> [sqlite3_uri_int64()], 3909 ** <li> [sqlite3_uri_key()], 3910 ** <li> [sqlite3_filename_database()], 3911 ** <li> [sqlite3_filename_journal()], or 3912 ** <li> [sqlite3_filename_wal()]. 3913 ** </ul> 3914 ** If a memory allocation error occurs, sqlite3_create_filename() might 3915 ** return a NULL pointer. The memory obtained from sqlite3_create_filename(X) 3916 ** must be released by a corresponding call to sqlite3_free_filename(Y). 3917 ** 3918 ** The P parameter in sqlite3_create_filename(D,J,W,N,P) should be an array 3919 ** of 2*N pointers to strings. Each pair of pointers in this array corresponds 3920 ** to a key and value for a query parameter. The P parameter may be a NULL 3921 ** pointer if N is zero. None of the 2*N pointers in the P array may be 3922 ** NULL pointers and key pointers should not be empty strings. 3923 ** None of the D, J, or W parameters to sqlite3_create_filename(D,J,W,N,P) may 3924 ** be NULL pointers, though they can be empty strings. 3925 ** 3926 ** The sqlite3_free_filename(Y) routine releases a memory allocation 3927 ** previously obtained from sqlite3_create_filename(). Invoking 3928 ** sqlite3_free_filename(Y) where Y is a NULL pointer is a harmless no-op. 3929 ** 3930 ** If the Y parameter to sqlite3_free_filename(Y) is anything other 3931 ** than a NULL pointer or a pointer previously acquired from 3932 ** sqlite3_create_filename(), then bad things such as heap 3933 ** corruption or segfaults may occur. The value Y should not be 3934 ** used again after sqlite3_free_filename(Y) has been called. This means 3935 ** that if the [sqlite3_vfs.xOpen()] method of a VFS has been called using Y, 3936 ** then the corresponding [sqlite3_module.xClose() method should also be 3937 ** invoked prior to calling sqlite3_free_filename(Y). 3938 */ 3939 SQLITE_API sqlite3_filename sqlite3_create_filename( 3940 const char *zDatabase, 3941 const char *zJournal, 3942 const char *zWal, 3943 int nParam, 3944 const char **azParam 3945 ); 3946 SQLITE_API void sqlite3_free_filename(sqlite3_filename); 3947 3948 /* 3949 ** CAPI3REF: Error Codes And Messages 3950 ** METHOD: sqlite3 3951 ** 3952 ** ^If the most recent sqlite3_* API call associated with 3953 ** [database connection] D failed, then the sqlite3_errcode(D) interface 3954 ** returns the numeric [result code] or [extended result code] for that 3955 ** API call. 3956 ** ^The sqlite3_extended_errcode() 3957 ** interface is the same except that it always returns the 3958 ** [extended result code] even when extended result codes are 3959 ** disabled. 3960 ** 3961 ** The values returned by sqlite3_errcode() and/or 3962 ** sqlite3_extended_errcode() might change with each API call. 3963 ** Except, there are some interfaces that are guaranteed to never 3964 ** change the value of the error code. The error-code preserving 3965 ** interfaces include the following: 3966 ** 3967 ** <ul> 3968 ** <li> sqlite3_errcode() 3969 ** <li> sqlite3_extended_errcode() 3970 ** <li> sqlite3_errmsg() 3971 ** <li> sqlite3_errmsg16() 3972 ** <li> sqlite3_error_offset() 3973 ** </ul> 3974 ** 3975 ** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language 3976 ** text that describes the error, as either UTF-8 or UTF-16 respectively, 3977 ** or NULL if no error message is available. 3978 ** (See how SQLite handles [invalid UTF] for exceptions to this rule.) 3979 ** ^(Memory to hold the error message string is managed internally. 3980 ** The application does not need to worry about freeing the result. 3981 ** However, the error string might be overwritten or deallocated by 3982 ** subsequent calls to other SQLite interface functions.)^ 3983 ** 3984 ** ^The sqlite3_errstr(E) interface returns the English-language text 3985 ** that describes the [result code] E, as UTF-8, or NULL if E is not an 3986 ** result code for which a text error message is available. 3987 ** ^(Memory to hold the error message string is managed internally 3988 ** and must not be freed by the application)^. 3989 ** 3990 ** ^If the most recent error references a specific token in the input 3991 ** SQL, the sqlite3_error_offset() interface returns the byte offset 3992 ** of the start of that token. ^The byte offset returned by 3993 ** sqlite3_error_offset() assumes that the input SQL is UTF8. 3994 ** ^If the most recent error does not reference a specific token in the input 3995 ** SQL, then the sqlite3_error_offset() function returns -1. 3996 ** 3997 ** When the serialized [threading mode] is in use, it might be the 3998 ** case that a second error occurs on a separate thread in between 3999 ** the time of the first error and the call to these interfaces. 4000 ** When that happens, the second error will be reported since these 4001 ** interfaces always report the most recent result. To avoid 4002 ** this, each thread can obtain exclusive use of the [database connection] D 4003 ** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning 4004 ** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after 4005 ** all calls to the interfaces listed here are completed. 4006 ** 4007 ** If an interface fails with SQLITE_MISUSE, that means the interface 4008 ** was invoked incorrectly by the application. In that case, the 4009 ** error code and message may or may not be set. 4010 */ 4011 SQLITE_API int sqlite3_errcode(sqlite3 *db); 4012 SQLITE_API int sqlite3_extended_errcode(sqlite3 *db); 4013 SQLITE_API const char *sqlite3_errmsg(sqlite3*); 4014 SQLITE_API const void *sqlite3_errmsg16(sqlite3*); 4015 SQLITE_API const char *sqlite3_errstr(int); 4016 SQLITE_API int sqlite3_error_offset(sqlite3 *db); 4017 4018 /* 4019 ** CAPI3REF: Prepared Statement Object 4020 ** KEYWORDS: {prepared statement} {prepared statements} 4021 ** 4022 ** An instance of this object represents a single SQL statement that 4023 ** has been compiled into binary form and is ready to be evaluated. 4024 ** 4025 ** Think of each SQL statement as a separate computer program. The 4026 ** original SQL text is source code. A prepared statement object 4027 ** is the compiled object code. All SQL must be converted into a 4028 ** prepared statement before it can be run. 4029 ** 4030 ** The life-cycle of a prepared statement object usually goes like this: 4031 ** 4032 ** <ol> 4033 ** <li> Create the prepared statement object using [sqlite3_prepare_v2()]. 4034 ** <li> Bind values to [parameters] using the sqlite3_bind_*() 4035 ** interfaces. 4036 ** <li> Run the SQL by calling [sqlite3_step()] one or more times. 4037 ** <li> Reset the prepared statement using [sqlite3_reset()] then go back 4038 ** to step 2. Do this zero or more times. 4039 ** <li> Destroy the object using [sqlite3_finalize()]. 4040 ** </ol> 4041 */ 4042 typedef struct sqlite3_stmt sqlite3_stmt; 4043 4044 /* 4045 ** CAPI3REF: Run-time Limits 4046 ** METHOD: sqlite3 4047 ** 4048 ** ^(This interface allows the size of various constructs to be limited 4049 ** on a connection by connection basis. The first parameter is the 4050 ** [database connection] whose limit is to be set or queried. The 4051 ** second parameter is one of the [limit categories] that define a 4052 ** class of constructs to be size limited. The third parameter is the 4053 ** new limit for that construct.)^ 4054 ** 4055 ** ^If the new limit is a negative number, the limit is unchanged. 4056 ** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a 4057 ** [limits | hard upper bound] 4058 ** set at compile-time by a C preprocessor macro called 4059 ** [limits | SQLITE_MAX_<i>NAME</i>]. 4060 ** (The "_LIMIT_" in the name is changed to "_MAX_".))^ 4061 ** ^Attempts to increase a limit above its hard upper bound are 4062 ** silently truncated to the hard upper bound. 4063 ** 4064 ** ^Regardless of whether or not the limit was changed, the 4065 ** [sqlite3_limit()] interface returns the prior value of the limit. 4066 ** ^Hence, to find the current value of a limit without changing it, 4067 ** simply invoke this interface with the third parameter set to -1. 4068 ** 4069 ** Run-time limits are intended for use in applications that manage 4070 ** both their own internal database and also databases that are controlled 4071 ** by untrusted external sources. An example application might be a 4072 ** web browser that has its own databases for storing history and 4073 ** separate databases controlled by JavaScript applications downloaded 4074 ** off the Internet. The internal databases can be given the 4075 ** large, default limits. Databases managed by external sources can 4076 ** be given much smaller limits designed to prevent a denial of service 4077 ** attack. Developers might also want to use the [sqlite3_set_authorizer()] 4078 ** interface to further control untrusted SQL. The size of the database 4079 ** created by an untrusted script can be contained using the 4080 ** [max_page_count] [PRAGMA]. 4081 ** 4082 ** New run-time limit categories may be added in future releases. 4083 */ 4084 SQLITE_API int sqlite3_limit(sqlite3*, int id, int newVal); 4085 4086 /* 4087 ** CAPI3REF: Run-Time Limit Categories 4088 ** KEYWORDS: {limit category} {*limit categories} 4089 ** 4090 ** These constants define various performance limits 4091 ** that can be lowered at run-time using [sqlite3_limit()]. 4092 ** The synopsis of the meanings of the various limits is shown below. 4093 ** Additional information is available at [limits | Limits in SQLite]. 4094 ** 4095 ** <dl> 4096 ** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt> 4097 ** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^ 4098 ** 4099 ** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt> 4100 ** <dd>The maximum length of an SQL statement, in bytes.</dd>)^ 4101 ** 4102 ** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt> 4103 ** <dd>The maximum number of columns in a table definition or in the 4104 ** result set of a [SELECT] or the maximum number of columns in an index 4105 ** or in an ORDER BY or GROUP BY clause.</dd>)^ 4106 ** 4107 ** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt> 4108 ** <dd>The maximum depth of the parse tree on any expression.</dd>)^ 4109 ** 4110 ** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt> 4111 ** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^ 4112 ** 4113 ** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt> 4114 ** <dd>The maximum number of instructions in a virtual machine program 4115 ** used to implement an SQL statement. If [sqlite3_prepare_v2()] or 4116 ** the equivalent tries to allocate space for more than this many opcodes 4117 ** in a single prepared statement, an SQLITE_NOMEM error is returned.</dd>)^ 4118 ** 4119 ** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt> 4120 ** <dd>The maximum number of arguments on a function.</dd>)^ 4121 ** 4122 ** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt> 4123 ** <dd>The maximum number of [ATTACH | attached databases].)^</dd> 4124 ** 4125 ** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]] 4126 ** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt> 4127 ** <dd>The maximum length of the pattern argument to the [LIKE] or 4128 ** [GLOB] operators.</dd>)^ 4129 ** 4130 ** [[SQLITE_LIMIT_VARIABLE_NUMBER]] 4131 ** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt> 4132 ** <dd>The maximum index number of any [parameter] in an SQL statement.)^ 4133 ** 4134 ** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt> 4135 ** <dd>The maximum depth of recursion for triggers.</dd>)^ 4136 ** 4137 ** [[SQLITE_LIMIT_WORKER_THREADS]] ^(<dt>SQLITE_LIMIT_WORKER_THREADS</dt> 4138 ** <dd>The maximum number of auxiliary worker threads that a single 4139 ** [prepared statement] may start.</dd>)^ 4140 ** </dl> 4141 */ 4142 #define SQLITE_LIMIT_LENGTH 0 4143 #define SQLITE_LIMIT_SQL_LENGTH 1 4144 #define SQLITE_LIMIT_COLUMN 2 4145 #define SQLITE_LIMIT_EXPR_DEPTH 3 4146 #define SQLITE_LIMIT_COMPOUND_SELECT 4 4147 #define SQLITE_LIMIT_VDBE_OP 5 4148 #define SQLITE_LIMIT_FUNCTION_ARG 6 4149 #define SQLITE_LIMIT_ATTACHED 7 4150 #define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8 4151 #define SQLITE_LIMIT_VARIABLE_NUMBER 9 4152 #define SQLITE_LIMIT_TRIGGER_DEPTH 10 4153 #define SQLITE_LIMIT_WORKER_THREADS 11 4154 4155 /* 4156 ** CAPI3REF: Prepare Flags 4157 ** 4158 ** These constants define various flags that can be passed into 4159 ** "prepFlags" parameter of the [sqlite3_prepare_v3()] and 4160 ** [sqlite3_prepare16_v3()] interfaces. 4161 ** 4162 ** New flags may be added in future releases of SQLite. 4163 ** 4164 ** <dl> 4165 ** [[SQLITE_PREPARE_PERSISTENT]] ^(<dt>SQLITE_PREPARE_PERSISTENT</dt> 4166 ** <dd>The SQLITE_PREPARE_PERSISTENT flag is a hint to the query planner 4167 ** that the prepared statement will be retained for a long time and 4168 ** probably reused many times.)^ ^Without this flag, [sqlite3_prepare_v3()] 4169 ** and [sqlite3_prepare16_v3()] assume that the prepared statement will 4170 ** be used just once or at most a few times and then destroyed using 4171 ** [sqlite3_finalize()] relatively soon. The current implementation acts 4172 ** on this hint by avoiding the use of [lookaside memory] so as not to 4173 ** deplete the limited store of lookaside memory. Future versions of 4174 ** SQLite may act on this hint differently. 4175 ** 4176 ** [[SQLITE_PREPARE_NORMALIZE]] <dt>SQLITE_PREPARE_NORMALIZE</dt> 4177 ** <dd>The SQLITE_PREPARE_NORMALIZE flag is a no-op. This flag used 4178 ** to be required for any prepared statement that wanted to use the 4179 ** [sqlite3_normalized_sql()] interface. However, the 4180 ** [sqlite3_normalized_sql()] interface is now available to all 4181 ** prepared statements, regardless of whether or not they use this 4182 ** flag. 4183 ** 4184 ** [[SQLITE_PREPARE_NO_VTAB]] <dt>SQLITE_PREPARE_NO_VTAB</dt> 4185 ** <dd>The SQLITE_PREPARE_NO_VTAB flag causes the SQL compiler 4186 ** to return an error (error code SQLITE_ERROR) if the statement uses 4187 ** any virtual tables. 4188 ** </dl> 4189 */ 4190 #define SQLITE_PREPARE_PERSISTENT 0x01 4191 #define SQLITE_PREPARE_NORMALIZE 0x02 4192 #define SQLITE_PREPARE_NO_VTAB 0x04 4193 4194 /* 4195 ** CAPI3REF: Compiling An SQL Statement 4196 ** KEYWORDS: {SQL statement compiler} 4197 ** METHOD: sqlite3 4198 ** CONSTRUCTOR: sqlite3_stmt 4199 ** 4200 ** To execute an SQL statement, it must first be compiled into a byte-code 4201 ** program using one of these routines. Or, in other words, these routines 4202 ** are constructors for the [prepared statement] object. 4203 ** 4204 ** The preferred routine to use is [sqlite3_prepare_v2()]. The 4205 ** [sqlite3_prepare()] interface is legacy and should be avoided. 4206 ** [sqlite3_prepare_v3()] has an extra "prepFlags" option that is used 4207 ** for special purposes. 4208 ** 4209 ** The use of the UTF-8 interfaces is preferred, as SQLite currently 4210 ** does all parsing using UTF-8. The UTF-16 interfaces are provided 4211 ** as a convenience. The UTF-16 interfaces work by converting the 4212 ** input text into UTF-8, then invoking the corresponding UTF-8 interface. 4213 ** 4214 ** The first argument, "db", is a [database connection] obtained from a 4215 ** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or 4216 ** [sqlite3_open16()]. The database connection must not have been closed. 4217 ** 4218 ** The second argument, "zSql", is the statement to be compiled, encoded 4219 ** as either UTF-8 or UTF-16. The sqlite3_prepare(), sqlite3_prepare_v2(), 4220 ** and sqlite3_prepare_v3() 4221 ** interfaces use UTF-8, and sqlite3_prepare16(), sqlite3_prepare16_v2(), 4222 ** and sqlite3_prepare16_v3() use UTF-16. 4223 ** 4224 ** ^If the nByte argument is negative, then zSql is read up to the 4225 ** first zero terminator. ^If nByte is positive, then it is the 4226 ** number of bytes read from zSql. ^If nByte is zero, then no prepared 4227 ** statement is generated. 4228 ** If the caller knows that the supplied string is nul-terminated, then 4229 ** there is a small performance advantage to passing an nByte parameter that 4230 ** is the number of bytes in the input string <i>including</i> 4231 ** the nul-terminator. 4232 ** 4233 ** ^If pzTail is not NULL then *pzTail is made to point to the first byte 4234 ** past the end of the first SQL statement in zSql. These routines only 4235 ** compile the first statement in zSql, so *pzTail is left pointing to 4236 ** what remains uncompiled. 4237 ** 4238 ** ^*ppStmt is left pointing to a compiled [prepared statement] that can be 4239 ** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set 4240 ** to NULL. ^If the input text contains no SQL (if the input is an empty 4241 ** string or a comment) then *ppStmt is set to NULL. 4242 ** The calling procedure is responsible for deleting the compiled 4243 ** SQL statement using [sqlite3_finalize()] after it has finished with it. 4244 ** ppStmt may not be NULL. 4245 ** 4246 ** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK]; 4247 ** otherwise an [error code] is returned. 4248 ** 4249 ** The sqlite3_prepare_v2(), sqlite3_prepare_v3(), sqlite3_prepare16_v2(), 4250 ** and sqlite3_prepare16_v3() interfaces are recommended for all new programs. 4251 ** The older interfaces (sqlite3_prepare() and sqlite3_prepare16()) 4252 ** are retained for backwards compatibility, but their use is discouraged. 4253 ** ^In the "vX" interfaces, the prepared statement 4254 ** that is returned (the [sqlite3_stmt] object) contains a copy of the 4255 ** original SQL text. This causes the [sqlite3_step()] interface to 4256 ** behave differently in three ways: 4257 ** 4258 ** <ol> 4259 ** <li> 4260 ** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it 4261 ** always used to do, [sqlite3_step()] will automatically recompile the SQL 4262 ** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY] 4263 ** retries will occur before sqlite3_step() gives up and returns an error. 4264 ** </li> 4265 ** 4266 ** <li> 4267 ** ^When an error occurs, [sqlite3_step()] will return one of the detailed 4268 ** [error codes] or [extended error codes]. ^The legacy behavior was that 4269 ** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code 4270 ** and the application would have to make a second call to [sqlite3_reset()] 4271 ** in order to find the underlying cause of the problem. With the "v2" prepare 4272 ** interfaces, the underlying reason for the error is returned immediately. 4273 ** </li> 4274 ** 4275 ** <li> 4276 ** ^If the specific value bound to a [parameter | host parameter] in the 4277 ** WHERE clause might influence the choice of query plan for a statement, 4278 ** then the statement will be automatically recompiled, as if there had been 4279 ** a schema change, on the first [sqlite3_step()] call following any change 4280 ** to the [sqlite3_bind_text | bindings] of that [parameter]. 4281 ** ^The specific value of a WHERE-clause [parameter] might influence the 4282 ** choice of query plan if the parameter is the left-hand side of a [LIKE] 4283 ** or [GLOB] operator or if the parameter is compared to an indexed column 4284 ** and the [SQLITE_ENABLE_STAT4] compile-time option is enabled. 4285 ** </li> 4286 ** </ol> 4287 ** 4288 ** <p>^sqlite3_prepare_v3() differs from sqlite3_prepare_v2() only in having 4289 ** the extra prepFlags parameter, which is a bit array consisting of zero or 4290 ** more of the [SQLITE_PREPARE_PERSISTENT|SQLITE_PREPARE_*] flags. ^The 4291 ** sqlite3_prepare_v2() interface works exactly the same as 4292 ** sqlite3_prepare_v3() with a zero prepFlags parameter. 4293 */ 4294 SQLITE_API int sqlite3_prepare( 4295 sqlite3 *db, /* Database handle */ 4296 const char *zSql, /* SQL statement, UTF-8 encoded */ 4297 int nByte, /* Maximum length of zSql in bytes. */ 4298 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4299 const char **pzTail /* OUT: Pointer to unused portion of zSql */ 4300 ); 4301 SQLITE_API int sqlite3_prepare_v2( 4302 sqlite3 *db, /* Database handle */ 4303 const char *zSql, /* SQL statement, UTF-8 encoded */ 4304 int nByte, /* Maximum length of zSql in bytes. */ 4305 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4306 const char **pzTail /* OUT: Pointer to unused portion of zSql */ 4307 ); 4308 SQLITE_API int sqlite3_prepare_v3( 4309 sqlite3 *db, /* Database handle */ 4310 const char *zSql, /* SQL statement, UTF-8 encoded */ 4311 int nByte, /* Maximum length of zSql in bytes. */ 4312 unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */ 4313 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4314 const char **pzTail /* OUT: Pointer to unused portion of zSql */ 4315 ); 4316 SQLITE_API int sqlite3_prepare16( 4317 sqlite3 *db, /* Database handle */ 4318 const void *zSql, /* SQL statement, UTF-16 encoded */ 4319 int nByte, /* Maximum length of zSql in bytes. */ 4320 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4321 const void **pzTail /* OUT: Pointer to unused portion of zSql */ 4322 ); 4323 SQLITE_API int sqlite3_prepare16_v2( 4324 sqlite3 *db, /* Database handle */ 4325 const void *zSql, /* SQL statement, UTF-16 encoded */ 4326 int nByte, /* Maximum length of zSql in bytes. */ 4327 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4328 const void **pzTail /* OUT: Pointer to unused portion of zSql */ 4329 ); 4330 SQLITE_API int sqlite3_prepare16_v3( 4331 sqlite3 *db, /* Database handle */ 4332 const void *zSql, /* SQL statement, UTF-16 encoded */ 4333 int nByte, /* Maximum length of zSql in bytes. */ 4334 unsigned int prepFlags, /* Zero or more SQLITE_PREPARE_ flags */ 4335 sqlite3_stmt **ppStmt, /* OUT: Statement handle */ 4336 const void **pzTail /* OUT: Pointer to unused portion of zSql */ 4337 ); 4338 4339 /* 4340 ** CAPI3REF: Retrieving Statement SQL 4341 ** METHOD: sqlite3_stmt 4342 ** 4343 ** ^The sqlite3_sql(P) interface returns a pointer to a copy of the UTF-8 4344 ** SQL text used to create [prepared statement] P if P was 4345 ** created by [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], 4346 ** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()]. 4347 ** ^The sqlite3_expanded_sql(P) interface returns a pointer to a UTF-8 4348 ** string containing the SQL text of prepared statement P with 4349 ** [bound parameters] expanded. 4350 ** ^The sqlite3_normalized_sql(P) interface returns a pointer to a UTF-8 4351 ** string containing the normalized SQL text of prepared statement P. The 4352 ** semantics used to normalize a SQL statement are unspecified and subject 4353 ** to change. At a minimum, literal values will be replaced with suitable 4354 ** placeholders. 4355 ** 4356 ** ^(For example, if a prepared statement is created using the SQL 4357 ** text "SELECT $abc,:xyz" and if parameter $abc is bound to integer 2345 4358 ** and parameter :xyz is unbound, then sqlite3_sql() will return 4359 ** the original string, "SELECT $abc,:xyz" but sqlite3_expanded_sql() 4360 ** will return "SELECT 2345,NULL".)^ 4361 ** 4362 ** ^The sqlite3_expanded_sql() interface returns NULL if insufficient memory 4363 ** is available to hold the result, or if the result would exceed the 4364 ** the maximum string length determined by the [SQLITE_LIMIT_LENGTH]. 4365 ** 4366 ** ^The [SQLITE_TRACE_SIZE_LIMIT] compile-time option limits the size of 4367 ** bound parameter expansions. ^The [SQLITE_OMIT_TRACE] compile-time 4368 ** option causes sqlite3_expanded_sql() to always return NULL. 4369 ** 4370 ** ^The strings returned by sqlite3_sql(P) and sqlite3_normalized_sql(P) 4371 ** are managed by SQLite and are automatically freed when the prepared 4372 ** statement is finalized. 4373 ** ^The string returned by sqlite3_expanded_sql(P), on the other hand, 4374 ** is obtained from [sqlite3_malloc()] and must be freed by the application 4375 ** by passing it to [sqlite3_free()]. 4376 ** 4377 ** ^The sqlite3_normalized_sql() interface is only available if 4378 ** the [SQLITE_ENABLE_NORMALIZE] compile-time option is defined. 4379 */ 4380 SQLITE_API const char *sqlite3_sql(sqlite3_stmt *pStmt); 4381 SQLITE_API char *sqlite3_expanded_sql(sqlite3_stmt *pStmt); 4382 #ifdef SQLITE_ENABLE_NORMALIZE 4383 SQLITE_API const char *sqlite3_normalized_sql(sqlite3_stmt *pStmt); 4384 #endif 4385 4386 /* 4387 ** CAPI3REF: Determine If An SQL Statement Writes The Database 4388 ** METHOD: sqlite3_stmt 4389 ** 4390 ** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if 4391 ** and only if the [prepared statement] X makes no direct changes to 4392 ** the content of the database file. 4393 ** 4394 ** Note that [application-defined SQL functions] or 4395 ** [virtual tables] might change the database indirectly as a side effect. 4396 ** ^(For example, if an application defines a function "eval()" that 4397 ** calls [sqlite3_exec()], then the following SQL statement would 4398 ** change the database file through side-effects: 4399 ** 4400 ** <blockquote><pre> 4401 ** SELECT eval('DELETE FROM t1') FROM t2; 4402 ** </pre></blockquote> 4403 ** 4404 ** But because the [SELECT] statement does not change the database file 4405 ** directly, sqlite3_stmt_readonly() would still return true.)^ 4406 ** 4407 ** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK], 4408 ** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true, 4409 ** since the statements themselves do not actually modify the database but 4410 ** rather they control the timing of when other statements modify the 4411 ** database. ^The [ATTACH] and [DETACH] statements also cause 4412 ** sqlite3_stmt_readonly() to return true since, while those statements 4413 ** change the configuration of a database connection, they do not make 4414 ** changes to the content of the database files on disk. 4415 ** ^The sqlite3_stmt_readonly() interface returns true for [BEGIN] since 4416 ** [BEGIN] merely sets internal flags, but the [BEGIN|BEGIN IMMEDIATE] and 4417 ** [BEGIN|BEGIN EXCLUSIVE] commands do touch the database and so 4418 ** sqlite3_stmt_readonly() returns false for those commands. 4419 ** 4420 ** ^This routine returns false if there is any possibility that the 4421 ** statement might change the database file. ^A false return does 4422 ** not guarantee that the statement will change the database file. 4423 ** ^For example, an UPDATE statement might have a WHERE clause that 4424 ** makes it a no-op, but the sqlite3_stmt_readonly() result would still 4425 ** be false. ^Similarly, a CREATE TABLE IF NOT EXISTS statement is a 4426 ** read-only no-op if the table already exists, but 4427 ** sqlite3_stmt_readonly() still returns false for such a statement. 4428 ** 4429 ** ^If prepared statement X is an [EXPLAIN] or [EXPLAIN QUERY PLAN] 4430 ** statement, then sqlite3_stmt_readonly(X) returns the same value as 4431 ** if the EXPLAIN or EXPLAIN QUERY PLAN prefix were omitted. 4432 */ 4433 SQLITE_API int sqlite3_stmt_readonly(sqlite3_stmt *pStmt); 4434 4435 /* 4436 ** CAPI3REF: Query The EXPLAIN Setting For A Prepared Statement 4437 ** METHOD: sqlite3_stmt 4438 ** 4439 ** ^The sqlite3_stmt_isexplain(S) interface returns 1 if the 4440 ** prepared statement S is an EXPLAIN statement, or 2 if the 4441 ** statement S is an EXPLAIN QUERY PLAN. 4442 ** ^The sqlite3_stmt_isexplain(S) interface returns 0 if S is 4443 ** an ordinary statement or a NULL pointer. 4444 */ 4445 SQLITE_API int sqlite3_stmt_isexplain(sqlite3_stmt *pStmt); 4446 4447 /* 4448 ** CAPI3REF: Change The EXPLAIN Setting For A Prepared Statement 4449 ** METHOD: sqlite3_stmt 4450 ** 4451 ** The sqlite3_stmt_explain(S,E) interface changes the EXPLAIN 4452 ** setting for [prepared statement] S. If E is zero, then S becomes 4453 ** a normal prepared statement. If E is 1, then S behaves as if 4454 ** its SQL text began with "[EXPLAIN]". If E is 2, then S behaves as if 4455 ** its SQL text began with "[EXPLAIN QUERY PLAN]". 4456 ** 4457 ** Calling sqlite3_stmt_explain(S,E) might cause S to be reprepared. 4458 ** SQLite tries to avoid a reprepare, but a reprepare might be necessary 4459 ** on the first transition into EXPLAIN or EXPLAIN QUERY PLAN mode. 4460 ** 4461 ** Because of the potential need to reprepare, a call to 4462 ** sqlite3_stmt_explain(S,E) will fail with SQLITE_ERROR if S cannot be 4463 ** reprepared because it was created using [sqlite3_prepare()] instead of 4464 ** the newer [sqlite3_prepare_v2()] or [sqlite3_prepare_v3()] interfaces and 4465 ** hence has no saved SQL text with which to reprepare. 4466 ** 4467 ** Changing the explain setting for a prepared statement does not change 4468 ** the original SQL text for the statement. Hence, if the SQL text originally 4469 ** began with EXPLAIN or EXPLAIN QUERY PLAN, but sqlite3_stmt_explain(S,0) 4470 ** is called to convert the statement into an ordinary statement, the EXPLAIN 4471 ** or EXPLAIN QUERY PLAN keywords will still appear in the sqlite3_sql(S) 4472 ** output, even though the statement now acts like a normal SQL statement. 4473 ** 4474 ** This routine returns SQLITE_OK if the explain mode is successfully 4475 ** changed, or an error code if the explain mode could not be changed. 4476 ** The explain mode cannot be changed while a statement is active. 4477 ** Hence, it is good practice to call [sqlite3_reset(S)] 4478 ** immediately prior to calling sqlite3_stmt_explain(S,E). 4479 */ 4480 SQLITE_API int sqlite3_stmt_explain(sqlite3_stmt *pStmt, int eMode); 4481 4482 /* 4483 ** CAPI3REF: Determine If A Prepared Statement Has Been Reset 4484 ** METHOD: sqlite3_stmt 4485 ** 4486 ** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the 4487 ** [prepared statement] S has been stepped at least once using 4488 ** [sqlite3_step(S)] but has neither run to completion (returned 4489 ** [SQLITE_DONE] from [sqlite3_step(S)]) nor 4490 ** been reset using [sqlite3_reset(S)]. ^The sqlite3_stmt_busy(S) 4491 ** interface returns false if S is a NULL pointer. If S is not a 4492 ** NULL pointer and is not a pointer to a valid [prepared statement] 4493 ** object, then the behavior is undefined and probably undesirable. 4494 ** 4495 ** This interface can be used in combination [sqlite3_next_stmt()] 4496 ** to locate all prepared statements associated with a database 4497 ** connection that are in need of being reset. This can be used, 4498 ** for example, in diagnostic routines to search for prepared 4499 ** statements that are holding a transaction open. 4500 */ 4501 SQLITE_API int sqlite3_stmt_busy(sqlite3_stmt*); 4502 4503 /* 4504 ** CAPI3REF: Dynamically Typed Value Object 4505 ** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value} 4506 ** 4507 ** SQLite uses the sqlite3_value object to represent all values 4508 ** that can be stored in a database table. SQLite uses dynamic typing 4509 ** for the values it stores. ^Values stored in sqlite3_value objects 4510 ** can be integers, floating point values, strings, BLOBs, or NULL. 4511 ** 4512 ** An sqlite3_value object may be either "protected" or "unprotected". 4513 ** Some interfaces require a protected sqlite3_value. Other interfaces 4514 ** will accept either a protected or an unprotected sqlite3_value. 4515 ** Every interface that accepts sqlite3_value arguments specifies 4516 ** whether or not it requires a protected sqlite3_value. The 4517 ** [sqlite3_value_dup()] interface can be used to construct a new 4518 ** protected sqlite3_value from an unprotected sqlite3_value. 4519 ** 4520 ** The terms "protected" and "unprotected" refer to whether or not 4521 ** a mutex is held. An internal mutex is held for a protected 4522 ** sqlite3_value object but no mutex is held for an unprotected 4523 ** sqlite3_value object. If SQLite is compiled to be single-threaded 4524 ** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0) 4525 ** or if SQLite is run in one of reduced mutex modes 4526 ** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD] 4527 ** then there is no distinction between protected and unprotected 4528 ** sqlite3_value objects and they can be used interchangeably. However, 4529 ** for maximum code portability it is recommended that applications 4530 ** still make the distinction between protected and unprotected 4531 ** sqlite3_value objects even when not strictly required. 4532 ** 4533 ** ^The sqlite3_value objects that are passed as parameters into the 4534 ** implementation of [application-defined SQL functions] are protected. 4535 ** ^The sqlite3_value objects returned by [sqlite3_vtab_rhs_value()] 4536 ** are protected. 4537 ** ^The sqlite3_value object returned by 4538 ** [sqlite3_column_value()] is unprotected. 4539 ** Unprotected sqlite3_value objects may only be used as arguments 4540 ** to [sqlite3_result_value()], [sqlite3_bind_value()], and 4541 ** [sqlite3_value_dup()]. 4542 ** The [sqlite3_value_blob | sqlite3_value_type()] family of 4543 ** interfaces require protected sqlite3_value objects. 4544 */ 4545 typedef struct sqlite3_value sqlite3_value; 4546 4547 /* 4548 ** CAPI3REF: SQL Function Context Object 4549 ** 4550 ** The context in which an SQL function executes is stored in an 4551 ** sqlite3_context object. ^A pointer to an sqlite3_context object 4552 ** is always first parameter to [application-defined SQL functions]. 4553 ** The application-defined SQL function implementation will pass this 4554 ** pointer through into calls to [sqlite3_result_int | sqlite3_result()], 4555 ** [sqlite3_aggregate_context()], [sqlite3_user_data()], 4556 ** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()], 4557 ** and/or [sqlite3_set_auxdata()]. 4558 */ 4559 typedef struct sqlite3_context sqlite3_context; 4560 4561 /* 4562 ** CAPI3REF: Binding Values To Prepared Statements 4563 ** KEYWORDS: {host parameter} {host parameters} {host parameter name} 4564 ** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding} 4565 ** METHOD: sqlite3_stmt 4566 ** 4567 ** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants, 4568 ** literals may be replaced by a [parameter] that matches one of following 4569 ** templates: 4570 ** 4571 ** <ul> 4572 ** <li> ? 4573 ** <li> ?NNN 4574 ** <li> :VVV 4575 ** <li> @VVV 4576 ** <li> $VVV 4577 ** </ul> 4578 ** 4579 ** In the templates above, NNN represents an integer literal, 4580 ** and VVV represents an alphanumeric identifier.)^ ^The values of these 4581 ** parameters (also called "host parameter names" or "SQL parameters") 4582 ** can be set using the sqlite3_bind_*() routines defined here. 4583 ** 4584 ** ^The first argument to the sqlite3_bind_*() routines is always 4585 ** a pointer to the [sqlite3_stmt] object returned from 4586 ** [sqlite3_prepare_v2()] or its variants. 4587 ** 4588 ** ^The second argument is the index of the SQL parameter to be set. 4589 ** ^The leftmost SQL parameter has an index of 1. ^When the same named 4590 ** SQL parameter is used more than once, second and subsequent 4591 ** occurrences have the same index as the first occurrence. 4592 ** ^The index for named parameters can be looked up using the 4593 ** [sqlite3_bind_parameter_index()] API if desired. ^The index 4594 ** for "?NNN" parameters is the value of NNN. 4595 ** ^The NNN value must be between 1 and the [sqlite3_limit()] 4596 ** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 32766). 4597 ** 4598 ** ^The third argument is the value to bind to the parameter. 4599 ** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16() 4600 ** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter 4601 ** is ignored and the end result is the same as sqlite3_bind_null(). 4602 ** ^If the third parameter to sqlite3_bind_text() is not NULL, then 4603 ** it should be a pointer to well-formed UTF8 text. 4604 ** ^If the third parameter to sqlite3_bind_text16() is not NULL, then 4605 ** it should be a pointer to well-formed UTF16 text. 4606 ** ^If the third parameter to sqlite3_bind_text64() is not NULL, then 4607 ** it should be a pointer to a well-formed unicode string that is 4608 ** either UTF8 if the sixth parameter is SQLITE_UTF8, or UTF16 4609 ** otherwise. 4610 ** 4611 ** [[byte-order determination rules]] ^The byte-order of 4612 ** UTF16 input text is determined by the byte-order mark (BOM, U+FEFF) 4613 ** found in first character, which is removed, or in the absence of a BOM 4614 ** the byte order is the native byte order of the host 4615 ** machine for sqlite3_bind_text16() or the byte order specified in 4616 ** the 6th parameter for sqlite3_bind_text64().)^ 4617 ** ^If UTF16 input text contains invalid unicode 4618 ** characters, then SQLite might change those invalid characters 4619 ** into the unicode replacement character: U+FFFD. 4620 ** 4621 ** ^(In those routines that have a fourth argument, its value is the 4622 ** number of bytes in the parameter. To be clear: the value is the 4623 ** number of <u>bytes</u> in the value, not the number of characters.)^ 4624 ** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16() 4625 ** is negative, then the length of the string is 4626 ** the number of bytes up to the first zero terminator. 4627 ** If the fourth parameter to sqlite3_bind_blob() is negative, then 4628 ** the behavior is undefined. 4629 ** If a non-negative fourth parameter is provided to sqlite3_bind_text() 4630 ** or sqlite3_bind_text16() or sqlite3_bind_text64() then 4631 ** that parameter must be the byte offset 4632 ** where the NUL terminator would occur assuming the string were NUL 4633 ** terminated. If any NUL characters occurs at byte offsets less than 4634 ** the value of the fourth parameter then the resulting string value will 4635 ** contain embedded NULs. The result of expressions involving strings 4636 ** with embedded NULs is undefined. 4637 ** 4638 ** ^The fifth argument to the BLOB and string binding interfaces controls 4639 ** or indicates the lifetime of the object referenced by the third parameter. 4640 ** These three options exist: 4641 ** ^ (1) A destructor to dispose of the BLOB or string after SQLite has finished 4642 ** with it may be passed. ^It is called to dispose of the BLOB or string even 4643 ** if the call to the bind API fails, except the destructor is not called if 4644 ** the third parameter is a NULL pointer or the fourth parameter is negative. 4645 ** ^ (2) The special constant, [SQLITE_STATIC], may be passed to indicate that 4646 ** the application remains responsible for disposing of the object. ^In this 4647 ** case, the object and the provided pointer to it must remain valid until 4648 ** either the prepared statement is finalized or the same SQL parameter is 4649 ** bound to something else, whichever occurs sooner. 4650 ** ^ (3) The constant, [SQLITE_TRANSIENT], may be passed to indicate that the 4651 ** object is to be copied prior to the return from sqlite3_bind_*(). ^The 4652 ** object and pointer to it must remain valid until then. ^SQLite will then 4653 ** manage the lifetime of its private copy. 4654 ** 4655 ** ^The sixth argument to sqlite3_bind_text64() must be one of 4656 ** [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE] 4657 ** to specify the encoding of the text in the third parameter. If 4658 ** the sixth argument to sqlite3_bind_text64() is not one of the 4659 ** allowed values shown above, or if the text encoding is different 4660 ** from the encoding specified by the sixth parameter, then the behavior 4661 ** is undefined. 4662 ** 4663 ** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that 4664 ** is filled with zeroes. ^A zeroblob uses a fixed amount of memory 4665 ** (just an integer to hold its size) while it is being processed. 4666 ** Zeroblobs are intended to serve as placeholders for BLOBs whose 4667 ** content is later written using 4668 ** [sqlite3_blob_open | incremental BLOB I/O] routines. 4669 ** ^A negative value for the zeroblob results in a zero-length BLOB. 4670 ** 4671 ** ^The sqlite3_bind_pointer(S,I,P,T,D) routine causes the I-th parameter in 4672 ** [prepared statement] S to have an SQL value of NULL, but to also be 4673 ** associated with the pointer P of type T. ^D is either a NULL pointer or 4674 ** a pointer to a destructor function for P. ^SQLite will invoke the 4675 ** destructor D with a single argument of P when it is finished using 4676 ** P. The T parameter should be a static string, preferably a string 4677 ** literal. The sqlite3_bind_pointer() routine is part of the 4678 ** [pointer passing interface] added for SQLite 3.20.0. 4679 ** 4680 ** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer 4681 ** for the [prepared statement] or with a prepared statement for which 4682 ** [sqlite3_step()] has been called more recently than [sqlite3_reset()], 4683 ** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_() 4684 ** routine is passed a [prepared statement] that has been finalized, the 4685 ** result is undefined and probably harmful. 4686 ** 4687 ** ^Bindings are not cleared by the [sqlite3_reset()] routine. 4688 ** ^Unbound parameters are interpreted as NULL. 4689 ** 4690 ** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an 4691 ** [error code] if anything goes wrong. 4692 ** ^[SQLITE_TOOBIG] might be returned if the size of a string or BLOB 4693 ** exceeds limits imposed by [sqlite3_limit]([SQLITE_LIMIT_LENGTH]) or 4694 ** [SQLITE_MAX_LENGTH]. 4695 ** ^[SQLITE_RANGE] is returned if the parameter 4696 ** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails. 4697 ** 4698 ** See also: [sqlite3_bind_parameter_count()], 4699 ** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()]. 4700 */ 4701 SQLITE_API int sqlite3_bind_blob(sqlite3_stmt*, int, const void*, int n, void(*)(void*)); 4702 SQLITE_API int sqlite3_bind_blob64(sqlite3_stmt*, int, const void*, sqlite3_uint64, 4703 void(*)(void*)); 4704 SQLITE_API int sqlite3_bind_double(sqlite3_stmt*, int, double); 4705 SQLITE_API int sqlite3_bind_int(sqlite3_stmt*, int, int); 4706 SQLITE_API int sqlite3_bind_int64(sqlite3_stmt*, int, sqlite3_int64); 4707 SQLITE_API int sqlite3_bind_null(sqlite3_stmt*, int); 4708 SQLITE_API int sqlite3_bind_text(sqlite3_stmt*,int,const char*,int,void(*)(void*)); 4709 SQLITE_API int sqlite3_bind_text16(sqlite3_stmt*, int, const void*, int, void(*)(void*)); 4710 SQLITE_API int sqlite3_bind_text64(sqlite3_stmt*, int, const char*, sqlite3_uint64, 4711 void(*)(void*), unsigned char encoding); 4712 SQLITE_API int sqlite3_bind_value(sqlite3_stmt*, int, const sqlite3_value*); 4713 SQLITE_API int sqlite3_bind_pointer(sqlite3_stmt*, int, void*, const char*,void(*)(void*)); 4714 SQLITE_API int sqlite3_bind_zeroblob(sqlite3_stmt*, int, int n); 4715 SQLITE_API int sqlite3_bind_zeroblob64(sqlite3_stmt*, int, sqlite3_uint64); 4716 4717 /* 4718 ** CAPI3REF: Number Of SQL Parameters 4719 ** METHOD: sqlite3_stmt 4720 ** 4721 ** ^This routine can be used to find the number of [SQL parameters] 4722 ** in a [prepared statement]. SQL parameters are tokens of the 4723 ** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as 4724 ** placeholders for values that are [sqlite3_bind_blob | bound] 4725 ** to the parameters at a later time. 4726 ** 4727 ** ^(This routine actually returns the index of the largest (rightmost) 4728 ** parameter. For all forms except ?NNN, this will correspond to the 4729 ** number of unique parameters. If parameters of the ?NNN form are used, 4730 ** there may be gaps in the list.)^ 4731 ** 4732 ** See also: [sqlite3_bind_blob|sqlite3_bind()], 4733 ** [sqlite3_bind_parameter_name()], and 4734 ** [sqlite3_bind_parameter_index()]. 4735 */ 4736 SQLITE_API int sqlite3_bind_parameter_count(sqlite3_stmt*); 4737 4738 /* 4739 ** CAPI3REF: Name Of A Host Parameter 4740 ** METHOD: sqlite3_stmt 4741 ** 4742 ** ^The sqlite3_bind_parameter_name(P,N) interface returns 4743 ** the name of the N-th [SQL parameter] in the [prepared statement] P. 4744 ** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA" 4745 ** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA" 4746 ** respectively. 4747 ** In other words, the initial ":" or "$" or "@" or "?" 4748 ** is included as part of the name.)^ 4749 ** ^Parameters of the form "?" without a following integer have no name 4750 ** and are referred to as "nameless" or "anonymous parameters". 4751 ** 4752 ** ^The first host parameter has an index of 1, not 0. 4753 ** 4754 ** ^If the value N is out of range or if the N-th parameter is 4755 ** nameless, then NULL is returned. ^The returned string is 4756 ** always in UTF-8 encoding even if the named parameter was 4757 ** originally specified as UTF-16 in [sqlite3_prepare16()], 4758 ** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()]. 4759 ** 4760 ** See also: [sqlite3_bind_blob|sqlite3_bind()], 4761 ** [sqlite3_bind_parameter_count()], and 4762 ** [sqlite3_bind_parameter_index()]. 4763 */ 4764 SQLITE_API const char *sqlite3_bind_parameter_name(sqlite3_stmt*, int); 4765 4766 /* 4767 ** CAPI3REF: Index Of A Parameter With A Given Name 4768 ** METHOD: sqlite3_stmt 4769 ** 4770 ** ^Return the index of an SQL parameter given its name. ^The 4771 ** index value returned is suitable for use as the second 4772 ** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero 4773 ** is returned if no matching parameter is found. ^The parameter 4774 ** name must be given in UTF-8 even if the original statement 4775 ** was prepared from UTF-16 text using [sqlite3_prepare16_v2()] or 4776 ** [sqlite3_prepare16_v3()]. 4777 ** 4778 ** See also: [sqlite3_bind_blob|sqlite3_bind()], 4779 ** [sqlite3_bind_parameter_count()], and 4780 ** [sqlite3_bind_parameter_name()]. 4781 */ 4782 SQLITE_API int sqlite3_bind_parameter_index(sqlite3_stmt*, const char *zName); 4783 4784 /* 4785 ** CAPI3REF: Reset All Bindings On A Prepared Statement 4786 ** METHOD: sqlite3_stmt 4787 ** 4788 ** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset 4789 ** the [sqlite3_bind_blob | bindings] on a [prepared statement]. 4790 ** ^Use this routine to reset all host parameters to NULL. 4791 */ 4792 SQLITE_API int sqlite3_clear_bindings(sqlite3_stmt*); 4793 4794 /* 4795 ** CAPI3REF: Number Of Columns In A Result Set 4796 ** METHOD: sqlite3_stmt 4797 ** 4798 ** ^Return the number of columns in the result set returned by the 4799 ** [prepared statement]. ^If this routine returns 0, that means the 4800 ** [prepared statement] returns no data (for example an [UPDATE]). 4801 ** ^However, just because this routine returns a positive number does not 4802 ** mean that one or more rows of data will be returned. ^A SELECT statement 4803 ** will always have a positive sqlite3_column_count() but depending on the 4804 ** WHERE clause constraints and the table content, it might return no rows. 4805 ** 4806 ** See also: [sqlite3_data_count()] 4807 */ 4808 SQLITE_API int sqlite3_column_count(sqlite3_stmt *pStmt); 4809 4810 /* 4811 ** CAPI3REF: Column Names In A Result Set 4812 ** METHOD: sqlite3_stmt 4813 ** 4814 ** ^These routines return the name assigned to a particular column 4815 ** in the result set of a [SELECT] statement. ^The sqlite3_column_name() 4816 ** interface returns a pointer to a zero-terminated UTF-8 string 4817 ** and sqlite3_column_name16() returns a pointer to a zero-terminated 4818 ** UTF-16 string. ^The first parameter is the [prepared statement] 4819 ** that implements the [SELECT] statement. ^The second parameter is the 4820 ** column number. ^The leftmost column is number 0. 4821 ** 4822 ** ^The returned string pointer is valid until either the [prepared statement] 4823 ** is destroyed by [sqlite3_finalize()] or until the statement is automatically 4824 ** reprepared by the first call to [sqlite3_step()] for a particular run 4825 ** or until the next call to 4826 ** sqlite3_column_name() or sqlite3_column_name16() on the same column. 4827 ** 4828 ** ^If sqlite3_malloc() fails during the processing of either routine 4829 ** (for example during a conversion from UTF-8 to UTF-16) then a 4830 ** NULL pointer is returned. 4831 ** 4832 ** ^The name of a result column is the value of the "AS" clause for 4833 ** that column, if there is an AS clause. If there is no AS clause 4834 ** then the name of the column is unspecified and may change from 4835 ** one release of SQLite to the next. 4836 */ 4837 SQLITE_API const char *sqlite3_column_name(sqlite3_stmt*, int N); 4838 SQLITE_API const void *sqlite3_column_name16(sqlite3_stmt*, int N); 4839 4840 /* 4841 ** CAPI3REF: Source Of Data In A Query Result 4842 ** METHOD: sqlite3_stmt 4843 ** 4844 ** ^These routines provide a means to determine the database, table, and 4845 ** table column that is the origin of a particular result column in 4846 ** [SELECT] statement. 4847 ** ^The name of the database or table or column can be returned as 4848 ** either a UTF-8 or UTF-16 string. ^The _database_ routines return 4849 ** the database name, the _table_ routines return the table name, and 4850 ** the origin_ routines return the column name. 4851 ** ^The returned string is valid until the [prepared statement] is destroyed 4852 ** using [sqlite3_finalize()] or until the statement is automatically 4853 ** reprepared by the first call to [sqlite3_step()] for a particular run 4854 ** or until the same information is requested 4855 ** again in a different encoding. 4856 ** 4857 ** ^The names returned are the original un-aliased names of the 4858 ** database, table, and column. 4859 ** 4860 ** ^The first argument to these interfaces is a [prepared statement]. 4861 ** ^These functions return information about the Nth result column returned by 4862 ** the statement, where N is the second function argument. 4863 ** ^The left-most column is column 0 for these routines. 4864 ** 4865 ** ^If the Nth column returned by the statement is an expression or 4866 ** subquery and is not a column value, then all of these functions return 4867 ** NULL. ^These routines might also return NULL if a memory allocation error 4868 ** occurs. ^Otherwise, they return the name of the attached database, table, 4869 ** or column that query result column was extracted from. 4870 ** 4871 ** ^As with all other SQLite APIs, those whose names end with "16" return 4872 ** UTF-16 encoded strings and the other functions return UTF-8. 4873 ** 4874 ** ^These APIs are only available if the library was compiled with the 4875 ** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol. 4876 ** 4877 ** If two or more threads call one or more 4878 ** [sqlite3_column_database_name | column metadata interfaces] 4879 ** for the same [prepared statement] and result column 4880 ** at the same time then the results are undefined. 4881 */ 4882 SQLITE_API const char *sqlite3_column_database_name(sqlite3_stmt*,int); 4883 SQLITE_API const void *sqlite3_column_database_name16(sqlite3_stmt*,int); 4884 SQLITE_API const char *sqlite3_column_table_name(sqlite3_stmt*,int); 4885 SQLITE_API const void *sqlite3_column_table_name16(sqlite3_stmt*,int); 4886 SQLITE_API const char *sqlite3_column_origin_name(sqlite3_stmt*,int); 4887 SQLITE_API const void *sqlite3_column_origin_name16(sqlite3_stmt*,int); 4888 4889 /* 4890 ** CAPI3REF: Declared Datatype Of A Query Result 4891 ** METHOD: sqlite3_stmt 4892 ** 4893 ** ^(The first parameter is a [prepared statement]. 4894 ** If this statement is a [SELECT] statement and the Nth column of the 4895 ** returned result set of that [SELECT] is a table column (not an 4896 ** expression or subquery) then the declared type of the table 4897 ** column is returned.)^ ^If the Nth column of the result set is an 4898 ** expression or subquery, then a NULL pointer is returned. 4899 ** ^The returned string is always UTF-8 encoded. 4900 ** 4901 ** ^(For example, given the database schema: 4902 ** 4903 ** CREATE TABLE t1(c1 VARIANT); 4904 ** 4905 ** and the following statement to be compiled: 4906 ** 4907 ** SELECT c1 + 1, c1 FROM t1; 4908 ** 4909 ** this routine would return the string "VARIANT" for the second result 4910 ** column (i==1), and a NULL pointer for the first result column (i==0).)^ 4911 ** 4912 ** ^SQLite uses dynamic run-time typing. ^So just because a column 4913 ** is declared to contain a particular type does not mean that the 4914 ** data stored in that column is of the declared type. SQLite is 4915 ** strongly typed, but the typing is dynamic not static. ^Type 4916 ** is associated with individual values, not with the containers 4917 ** used to hold those values. 4918 */ 4919 SQLITE_API const char *sqlite3_column_decltype(sqlite3_stmt*,int); 4920 SQLITE_API const void *sqlite3_column_decltype16(sqlite3_stmt*,int); 4921 4922 /* 4923 ** CAPI3REF: Evaluate An SQL Statement 4924 ** METHOD: sqlite3_stmt 4925 ** 4926 ** After a [prepared statement] has been prepared using any of 4927 ** [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], [sqlite3_prepare16_v2()], 4928 ** or [sqlite3_prepare16_v3()] or one of the legacy 4929 ** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function 4930 ** must be called one or more times to evaluate the statement. 4931 ** 4932 ** The details of the behavior of the sqlite3_step() interface depend 4933 ** on whether the statement was prepared using the newer "vX" interfaces 4934 ** [sqlite3_prepare_v3()], [sqlite3_prepare_v2()], [sqlite3_prepare16_v3()], 4935 ** [sqlite3_prepare16_v2()] or the older legacy 4936 ** interfaces [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the 4937 ** new "vX" interface is recommended for new applications but the legacy 4938 ** interface will continue to be supported. 4939 ** 4940 ** ^In the legacy interface, the return value will be either [SQLITE_BUSY], 4941 ** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE]. 4942 ** ^With the "v2" interface, any of the other [result codes] or 4943 ** [extended result codes] might be returned as well. 4944 ** 4945 ** ^[SQLITE_BUSY] means that the database engine was unable to acquire the 4946 ** database locks it needs to do its job. ^If the statement is a [COMMIT] 4947 ** or occurs outside of an explicit transaction, then you can retry the 4948 ** statement. If the statement is not a [COMMIT] and occurs within an 4949 ** explicit transaction then you should rollback the transaction before 4950 ** continuing. 4951 ** 4952 ** ^[SQLITE_DONE] means that the statement has finished executing 4953 ** successfully. sqlite3_step() should not be called again on this virtual 4954 ** machine without first calling [sqlite3_reset()] to reset the virtual 4955 ** machine back to its initial state. 4956 ** 4957 ** ^If the SQL statement being executed returns any data, then [SQLITE_ROW] 4958 ** is returned each time a new row of data is ready for processing by the 4959 ** caller. The values may be accessed using the [column access functions]. 4960 ** sqlite3_step() is called again to retrieve the next row of data. 4961 ** 4962 ** ^[SQLITE_ERROR] means that a run-time error (such as a constraint 4963 ** violation) has occurred. sqlite3_step() should not be called again on 4964 ** the VM. More information may be found by calling [sqlite3_errmsg()]. 4965 ** ^With the legacy interface, a more specific error code (for example, 4966 ** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth) 4967 ** can be obtained by calling [sqlite3_reset()] on the 4968 ** [prepared statement]. ^In the "v2" interface, 4969 ** the more specific error code is returned directly by sqlite3_step(). 4970 ** 4971 ** [SQLITE_MISUSE] means that the this routine was called inappropriately. 4972 ** Perhaps it was called on a [prepared statement] that has 4973 ** already been [sqlite3_finalize | finalized] or on one that had 4974 ** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could 4975 ** be the case that the same database connection is being used by two or 4976 ** more threads at the same moment in time. 4977 ** 4978 ** For all versions of SQLite up to and including 3.6.23.1, a call to 4979 ** [sqlite3_reset()] was required after sqlite3_step() returned anything 4980 ** other than [SQLITE_ROW] before any subsequent invocation of 4981 ** sqlite3_step(). Failure to reset the prepared statement using 4982 ** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from 4983 ** sqlite3_step(). But after [version 3.6.23.1] ([dateof:3.6.23.1], 4984 ** sqlite3_step() began 4985 ** calling [sqlite3_reset()] automatically in this circumstance rather 4986 ** than returning [SQLITE_MISUSE]. This is not considered a compatibility 4987 ** break because any application that ever receives an SQLITE_MISUSE error 4988 ** is broken by definition. The [SQLITE_OMIT_AUTORESET] compile-time option 4989 ** can be used to restore the legacy behavior. 4990 ** 4991 ** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step() 4992 ** API always returns a generic error code, [SQLITE_ERROR], following any 4993 ** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call 4994 ** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the 4995 ** specific [error codes] that better describes the error. 4996 ** We admit that this is a goofy design. The problem has been fixed 4997 ** with the "v2" interface. If you prepare all of your SQL statements 4998 ** using [sqlite3_prepare_v3()] or [sqlite3_prepare_v2()] 4999 ** or [sqlite3_prepare16_v2()] or [sqlite3_prepare16_v3()] instead 5000 ** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces, 5001 ** then the more specific [error codes] are returned directly 5002 ** by sqlite3_step(). The use of the "vX" interfaces is recommended. 5003 */ 5004 SQLITE_API int sqlite3_step(sqlite3_stmt*); 5005 5006 /* 5007 ** CAPI3REF: Number of columns in a result set 5008 ** METHOD: sqlite3_stmt 5009 ** 5010 ** ^The sqlite3_data_count(P) interface returns the number of columns in the 5011 ** current row of the result set of [prepared statement] P. 5012 ** ^If prepared statement P does not have results ready to return 5013 ** (via calls to the [sqlite3_column_int | sqlite3_column()] family of 5014 ** interfaces) then sqlite3_data_count(P) returns 0. 5015 ** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer. 5016 ** ^The sqlite3_data_count(P) routine returns 0 if the previous call to 5017 ** [sqlite3_step](P) returned [SQLITE_DONE]. ^The sqlite3_data_count(P) 5018 ** will return non-zero if previous call to [sqlite3_step](P) returned 5019 ** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum] 5020 ** where it always returns zero since each step of that multi-step 5021 ** pragma returns 0 columns of data. 5022 ** 5023 ** See also: [sqlite3_column_count()] 5024 */ 5025 SQLITE_API int sqlite3_data_count(sqlite3_stmt *pStmt); 5026 5027 /* 5028 ** CAPI3REF: Fundamental Datatypes 5029 ** KEYWORDS: SQLITE_TEXT 5030 ** 5031 ** ^(Every value in SQLite has one of five fundamental datatypes: 5032 ** 5033 ** <ul> 5034 ** <li> 64-bit signed integer 5035 ** <li> 64-bit IEEE floating point number 5036 ** <li> string 5037 ** <li> BLOB 5038 ** <li> NULL 5039 ** </ul>)^ 5040 ** 5041 ** These constants are codes for each of those types. 5042 ** 5043 ** Note that the SQLITE_TEXT constant was also used in SQLite version 2 5044 ** for a completely different meaning. Software that links against both 5045 ** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not 5046 ** SQLITE_TEXT. 5047 */ 5048 #define SQLITE_INTEGER 1 5049 #define SQLITE_FLOAT 2 5050 #define SQLITE_BLOB 4 5051 #define SQLITE_NULL 5 5052 #ifdef SQLITE_TEXT 5053 # undef SQLITE_TEXT 5054 #else 5055 # define SQLITE_TEXT 3 5056 #endif 5057 #define SQLITE3_TEXT 3 5058 5059 /* 5060 ** CAPI3REF: Result Values From A Query 5061 ** KEYWORDS: {column access functions} 5062 ** METHOD: sqlite3_stmt 5063 ** 5064 ** <b>Summary:</b> 5065 ** <blockquote><table border=0 cellpadding=0 cellspacing=0> 5066 ** <tr><td><b>sqlite3_column_blob</b><td>→<td>BLOB result 5067 ** <tr><td><b>sqlite3_column_double</b><td>→<td>REAL result 5068 ** <tr><td><b>sqlite3_column_int</b><td>→<td>32-bit INTEGER result 5069 ** <tr><td><b>sqlite3_column_int64</b><td>→<td>64-bit INTEGER result 5070 ** <tr><td><b>sqlite3_column_text</b><td>→<td>UTF-8 TEXT result 5071 ** <tr><td><b>sqlite3_column_text16</b><td>→<td>UTF-16 TEXT result 5072 ** <tr><td><b>sqlite3_column_value</b><td>→<td>The result as an 5073 ** [sqlite3_value|unprotected sqlite3_value] object. 5074 ** <tr><td> <td> <td> 5075 ** <tr><td><b>sqlite3_column_bytes</b><td>→<td>Size of a BLOB 5076 ** or a UTF-8 TEXT result in bytes 5077 ** <tr><td><b>sqlite3_column_bytes16 </b> 5078 ** <td>→ <td>Size of UTF-16 5079 ** TEXT in bytes 5080 ** <tr><td><b>sqlite3_column_type</b><td>→<td>Default 5081 ** datatype of the result 5082 ** </table></blockquote> 5083 ** 5084 ** <b>Details:</b> 5085 ** 5086 ** ^These routines return information about a single column of the current 5087 ** result row of a query. ^In every case the first argument is a pointer 5088 ** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*] 5089 ** that was returned from [sqlite3_prepare_v2()] or one of its variants) 5090 ** and the second argument is the index of the column for which information 5091 ** should be returned. ^The leftmost column of the result set has the index 0. 5092 ** ^The number of columns in the result can be determined using 5093 ** [sqlite3_column_count()]. 5094 ** 5095 ** If the SQL statement does not currently point to a valid row, or if the 5096 ** column index is out of range, the result is undefined. 5097 ** These routines may only be called when the most recent call to 5098 ** [sqlite3_step()] has returned [SQLITE_ROW] and neither 5099 ** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently. 5100 ** If any of these routines are called after [sqlite3_reset()] or 5101 ** [sqlite3_finalize()] or after [sqlite3_step()] has returned 5102 ** something other than [SQLITE_ROW], the results are undefined. 5103 ** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()] 5104 ** are called from a different thread while any of these routines 5105 ** are pending, then the results are undefined. 5106 ** 5107 ** The first six interfaces (_blob, _double, _int, _int64, _text, and _text16) 5108 ** each return the value of a result column in a specific data format. If 5109 ** the result column is not initially in the requested format (for example, 5110 ** if the query returns an integer but the sqlite3_column_text() interface 5111 ** is used to extract the value) then an automatic type conversion is performed. 5112 ** 5113 ** ^The sqlite3_column_type() routine returns the 5114 ** [SQLITE_INTEGER | datatype code] for the initial data type 5115 ** of the result column. ^The returned value is one of [SQLITE_INTEGER], 5116 ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. 5117 ** The return value of sqlite3_column_type() can be used to decide which 5118 ** of the first six interface should be used to extract the column value. 5119 ** The value returned by sqlite3_column_type() is only meaningful if no 5120 ** automatic type conversions have occurred for the value in question. 5121 ** After a type conversion, the result of calling sqlite3_column_type() 5122 ** is undefined, though harmless. Future 5123 ** versions of SQLite may change the behavior of sqlite3_column_type() 5124 ** following a type conversion. 5125 ** 5126 ** If the result is a BLOB or a TEXT string, then the sqlite3_column_bytes() 5127 ** or sqlite3_column_bytes16() interfaces can be used to determine the size 5128 ** of that BLOB or string. 5129 ** 5130 ** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes() 5131 ** routine returns the number of bytes in that BLOB or string. 5132 ** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts 5133 ** the string to UTF-8 and then returns the number of bytes. 5134 ** ^If the result is a numeric value then sqlite3_column_bytes() uses 5135 ** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns 5136 ** the number of bytes in that string. 5137 ** ^If the result is NULL, then sqlite3_column_bytes() returns zero. 5138 ** 5139 ** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16() 5140 ** routine returns the number of bytes in that BLOB or string. 5141 ** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts 5142 ** the string to UTF-16 and then returns the number of bytes. 5143 ** ^If the result is a numeric value then sqlite3_column_bytes16() uses 5144 ** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns 5145 ** the number of bytes in that string. 5146 ** ^If the result is NULL, then sqlite3_column_bytes16() returns zero. 5147 ** 5148 ** ^The values returned by [sqlite3_column_bytes()] and 5149 ** [sqlite3_column_bytes16()] do not include the zero terminators at the end 5150 ** of the string. ^For clarity: the values returned by 5151 ** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of 5152 ** bytes in the string, not the number of characters. 5153 ** 5154 ** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(), 5155 ** even empty strings, are always zero-terminated. ^The return 5156 ** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer. 5157 ** 5158 ** ^Strings returned by sqlite3_column_text16() always have the endianness 5159 ** which is native to the platform, regardless of the text encoding set 5160 ** for the database. 5161 ** 5162 ** <b>Warning:</b> ^The object returned by [sqlite3_column_value()] is an 5163 ** [unprotected sqlite3_value] object. In a multithreaded environment, 5164 ** an unprotected sqlite3_value object may only be used safely with 5165 ** [sqlite3_bind_value()] and [sqlite3_result_value()]. 5166 ** If the [unprotected sqlite3_value] object returned by 5167 ** [sqlite3_column_value()] is used in any other way, including calls 5168 ** to routines like [sqlite3_value_int()], [sqlite3_value_text()], 5169 ** or [sqlite3_value_bytes()], the behavior is not threadsafe. 5170 ** Hence, the sqlite3_column_value() interface 5171 ** is normally only useful within the implementation of 5172 ** [application-defined SQL functions] or [virtual tables], not within 5173 ** top-level application code. 5174 ** 5175 ** These routines may attempt to convert the datatype of the result. 5176 ** ^For example, if the internal representation is FLOAT and a text result 5177 ** is requested, [sqlite3_snprintf()] is used internally to perform the 5178 ** conversion automatically. ^(The following table details the conversions 5179 ** that are applied: 5180 ** 5181 ** <blockquote> 5182 ** <table border="1"> 5183 ** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion 5184 ** 5185 ** <tr><td> NULL <td> INTEGER <td> Result is 0 5186 ** <tr><td> NULL <td> FLOAT <td> Result is 0.0 5187 ** <tr><td> NULL <td> TEXT <td> Result is a NULL pointer 5188 ** <tr><td> NULL <td> BLOB <td> Result is a NULL pointer 5189 ** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float 5190 ** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer 5191 ** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT 5192 ** <tr><td> FLOAT <td> INTEGER <td> [CAST] to INTEGER 5193 ** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float 5194 ** <tr><td> FLOAT <td> BLOB <td> [CAST] to BLOB 5195 ** <tr><td> TEXT <td> INTEGER <td> [CAST] to INTEGER 5196 ** <tr><td> TEXT <td> FLOAT <td> [CAST] to REAL 5197 ** <tr><td> TEXT <td> BLOB <td> No change 5198 ** <tr><td> BLOB <td> INTEGER <td> [CAST] to INTEGER 5199 ** <tr><td> BLOB <td> FLOAT <td> [CAST] to REAL 5200 ** <tr><td> BLOB <td> TEXT <td> [CAST] to TEXT, ensure zero terminator 5201 ** </table> 5202 ** </blockquote>)^ 5203 ** 5204 ** Note that when type conversions occur, pointers returned by prior 5205 ** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or 5206 ** sqlite3_column_text16() may be invalidated. 5207 ** Type conversions and pointer invalidations might occur 5208 ** in the following cases: 5209 ** 5210 ** <ul> 5211 ** <li> The initial content is a BLOB and sqlite3_column_text() or 5212 ** sqlite3_column_text16() is called. A zero-terminator might 5213 ** need to be added to the string.</li> 5214 ** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or 5215 ** sqlite3_column_text16() is called. The content must be converted 5216 ** to UTF-16.</li> 5217 ** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or 5218 ** sqlite3_column_text() is called. The content must be converted 5219 ** to UTF-8.</li> 5220 ** </ul> 5221 ** 5222 ** ^Conversions between UTF-16be and UTF-16le are always done in place and do 5223 ** not invalidate a prior pointer, though of course the content of the buffer 5224 ** that the prior pointer references will have been modified. Other kinds 5225 ** of conversion are done in place when it is possible, but sometimes they 5226 ** are not possible and in those cases prior pointers are invalidated. 5227 ** 5228 ** The safest policy is to invoke these routines 5229 ** in one of the following ways: 5230 ** 5231 ** <ul> 5232 ** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li> 5233 ** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li> 5234 ** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li> 5235 ** </ul> 5236 ** 5237 ** In other words, you should call sqlite3_column_text(), 5238 ** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result 5239 ** into the desired format, then invoke sqlite3_column_bytes() or 5240 ** sqlite3_column_bytes16() to find the size of the result. Do not mix calls 5241 ** to sqlite3_column_text() or sqlite3_column_blob() with calls to 5242 ** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16() 5243 ** with calls to sqlite3_column_bytes(). 5244 ** 5245 ** ^The pointers returned are valid until a type conversion occurs as 5246 ** described above, or until [sqlite3_step()] or [sqlite3_reset()] or 5247 ** [sqlite3_finalize()] is called. ^The memory space used to hold strings 5248 ** and BLOBs is freed automatically. Do not pass the pointers returned 5249 ** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into 5250 ** [sqlite3_free()]. 5251 ** 5252 ** As long as the input parameters are correct, these routines will only 5253 ** fail if an out-of-memory error occurs during a format conversion. 5254 ** Only the following subset of interfaces are subject to out-of-memory 5255 ** errors: 5256 ** 5257 ** <ul> 5258 ** <li> sqlite3_column_blob() 5259 ** <li> sqlite3_column_text() 5260 ** <li> sqlite3_column_text16() 5261 ** <li> sqlite3_column_bytes() 5262 ** <li> sqlite3_column_bytes16() 5263 ** </ul> 5264 ** 5265 ** If an out-of-memory error occurs, then the return value from these 5266 ** routines is the same as if the column had contained an SQL NULL value. 5267 ** Valid SQL NULL returns can be distinguished from out-of-memory errors 5268 ** by invoking the [sqlite3_errcode()] immediately after the suspect 5269 ** return value is obtained and before any 5270 ** other SQLite interface is called on the same [database connection]. 5271 */ 5272 SQLITE_API const void *sqlite3_column_blob(sqlite3_stmt*, int iCol); 5273 SQLITE_API double sqlite3_column_double(sqlite3_stmt*, int iCol); 5274 SQLITE_API int sqlite3_column_int(sqlite3_stmt*, int iCol); 5275 SQLITE_API sqlite3_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol); 5276 SQLITE_API const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol); 5277 SQLITE_API const void *sqlite3_column_text16(sqlite3_stmt*, int iCol); 5278 SQLITE_API sqlite3_value *sqlite3_column_value(sqlite3_stmt*, int iCol); 5279 SQLITE_API int sqlite3_column_bytes(sqlite3_stmt*, int iCol); 5280 SQLITE_API int sqlite3_column_bytes16(sqlite3_stmt*, int iCol); 5281 SQLITE_API int sqlite3_column_type(sqlite3_stmt*, int iCol); 5282 5283 /* 5284 ** CAPI3REF: Destroy A Prepared Statement Object 5285 ** DESTRUCTOR: sqlite3_stmt 5286 ** 5287 ** ^The sqlite3_finalize() function is called to delete a [prepared statement]. 5288 ** ^If the most recent evaluation of the statement encountered no errors 5289 ** or if the statement is never been evaluated, then sqlite3_finalize() returns 5290 ** SQLITE_OK. ^If the most recent evaluation of statement S failed, then 5291 ** sqlite3_finalize(S) returns the appropriate [error code] or 5292 ** [extended error code]. 5293 ** 5294 ** ^The sqlite3_finalize(S) routine can be called at any point during 5295 ** the life cycle of [prepared statement] S: 5296 ** before statement S is ever evaluated, after 5297 ** one or more calls to [sqlite3_reset()], or after any call 5298 ** to [sqlite3_step()] regardless of whether or not the statement has 5299 ** completed execution. 5300 ** 5301 ** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op. 5302 ** 5303 ** The application must finalize every [prepared statement] in order to avoid 5304 ** resource leaks. It is a grievous error for the application to try to use 5305 ** a prepared statement after it has been finalized. Any use of a prepared 5306 ** statement after it has been finalized can result in undefined and 5307 ** undesirable behavior such as segfaults and heap corruption. 5308 */ 5309 SQLITE_API int sqlite3_finalize(sqlite3_stmt *pStmt); 5310 5311 /* 5312 ** CAPI3REF: Reset A Prepared Statement Object 5313 ** METHOD: sqlite3_stmt 5314 ** 5315 ** The sqlite3_reset() function is called to reset a [prepared statement] 5316 ** object back to its initial state, ready to be re-executed. 5317 ** ^Any SQL statement variables that had values bound to them using 5318 ** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values. 5319 ** Use [sqlite3_clear_bindings()] to reset the bindings. 5320 ** 5321 ** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S 5322 ** back to the beginning of its program. 5323 ** 5324 ** ^The return code from [sqlite3_reset(S)] indicates whether or not 5325 ** the previous evaluation of prepared statement S completed successfully. 5326 ** ^If [sqlite3_step(S)] has never before been called on S or if 5327 ** [sqlite3_step(S)] has not been called since the previous call 5328 ** to [sqlite3_reset(S)], then [sqlite3_reset(S)] will return 5329 ** [SQLITE_OK]. 5330 ** 5331 ** ^If the most recent call to [sqlite3_step(S)] for the 5332 ** [prepared statement] S indicated an error, then 5333 ** [sqlite3_reset(S)] returns an appropriate [error code]. 5334 ** ^The [sqlite3_reset(S)] interface might also return an [error code] 5335 ** if there were no prior errors but the process of resetting 5336 ** the prepared statement caused a new error. ^For example, if an 5337 ** [INSERT] statement with a [RETURNING] clause is only stepped one time, 5338 ** that one call to [sqlite3_step(S)] might return SQLITE_ROW but 5339 ** the overall statement might still fail and the [sqlite3_reset(S)] call 5340 ** might return SQLITE_BUSY if locking constraints prevent the 5341 ** database change from committing. Therefore, it is important that 5342 ** applications check the return code from [sqlite3_reset(S)] even if 5343 ** no prior call to [sqlite3_step(S)] indicated a problem. 5344 ** 5345 ** ^The [sqlite3_reset(S)] interface does not change the values 5346 ** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S. 5347 */ 5348 SQLITE_API int sqlite3_reset(sqlite3_stmt *pStmt); 5349 5350 5351 /* 5352 ** CAPI3REF: Create Or Redefine SQL Functions 5353 ** KEYWORDS: {function creation routines} 5354 ** METHOD: sqlite3 5355 ** 5356 ** ^These functions (collectively known as "function creation routines") 5357 ** are used to add SQL functions or aggregates or to redefine the behavior 5358 ** of existing SQL functions or aggregates. The only differences between 5359 ** the three "sqlite3_create_function*" routines are the text encoding 5360 ** expected for the second parameter (the name of the function being 5361 ** created) and the presence or absence of a destructor callback for 5362 ** the application data pointer. Function sqlite3_create_window_function() 5363 ** is similar, but allows the user to supply the extra callback functions 5364 ** needed by [aggregate window functions]. 5365 ** 5366 ** ^The first parameter is the [database connection] to which the SQL 5367 ** function is to be added. ^If an application uses more than one database 5368 ** connection then application-defined SQL functions must be added 5369 ** to each database connection separately. 5370 ** 5371 ** ^The second parameter is the name of the SQL function to be created or 5372 ** redefined. ^The length of the name is limited to 255 bytes in a UTF-8 5373 ** representation, exclusive of the zero-terminator. ^Note that the name 5374 ** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes. 5375 ** ^Any attempt to create a function with a longer name 5376 ** will result in [SQLITE_MISUSE] being returned. 5377 ** 5378 ** ^The third parameter (nArg) 5379 ** is the number of arguments that the SQL function or 5380 ** aggregate takes. ^If this parameter is -1, then the SQL function or 5381 ** aggregate may take any number of arguments between 0 and the limit 5382 ** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third 5383 ** parameter is less than -1 or greater than 127 then the behavior is 5384 ** undefined. 5385 ** 5386 ** ^The fourth parameter, eTextRep, specifies what 5387 ** [SQLITE_UTF8 | text encoding] this SQL function prefers for 5388 ** its parameters. The application should set this parameter to 5389 ** [SQLITE_UTF16LE] if the function implementation invokes 5390 ** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the 5391 ** implementation invokes [sqlite3_value_text16be()] on an input, or 5392 ** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8] 5393 ** otherwise. ^The same SQL function may be registered multiple times using 5394 ** different preferred text encodings, with different implementations for 5395 ** each encoding. 5396 ** ^When multiple implementations of the same function are available, SQLite 5397 ** will pick the one that involves the least amount of data conversion. 5398 ** 5399 ** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC] 5400 ** to signal that the function will always return the same result given 5401 ** the same inputs within a single SQL statement. Most SQL functions are 5402 ** deterministic. The built-in [random()] SQL function is an example of a 5403 ** function that is not deterministic. The SQLite query planner is able to 5404 ** perform additional optimizations on deterministic functions, so use 5405 ** of the [SQLITE_DETERMINISTIC] flag is recommended where possible. 5406 ** 5407 ** ^The fourth parameter may also optionally include the [SQLITE_DIRECTONLY] 5408 ** flag, which if present prevents the function from being invoked from 5409 ** within VIEWs, TRIGGERs, CHECK constraints, generated column expressions, 5410 ** index expressions, or the WHERE clause of partial indexes. 5411 ** 5412 ** For best security, the [SQLITE_DIRECTONLY] flag is recommended for 5413 ** all application-defined SQL functions that do not need to be 5414 ** used inside of triggers, view, CHECK constraints, or other elements of 5415 ** the database schema. This flags is especially recommended for SQL 5416 ** functions that have side effects or reveal internal application state. 5417 ** Without this flag, an attacker might be able to modify the schema of 5418 ** a database file to include invocations of the function with parameters 5419 ** chosen by the attacker, which the application will then execute when 5420 ** the database file is opened and read. 5421 ** 5422 ** ^(The fifth parameter is an arbitrary pointer. The implementation of the 5423 ** function can gain access to this pointer using [sqlite3_user_data()].)^ 5424 ** 5425 ** ^The sixth, seventh and eighth parameters passed to the three 5426 ** "sqlite3_create_function*" functions, xFunc, xStep and xFinal, are 5427 ** pointers to C-language functions that implement the SQL function or 5428 ** aggregate. ^A scalar SQL function requires an implementation of the xFunc 5429 ** callback only; NULL pointers must be passed as the xStep and xFinal 5430 ** parameters. ^An aggregate SQL function requires an implementation of xStep 5431 ** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing 5432 ** SQL function or aggregate, pass NULL pointers for all three function 5433 ** callbacks. 5434 ** 5435 ** ^The sixth, seventh, eighth and ninth parameters (xStep, xFinal, xValue 5436 ** and xInverse) passed to sqlite3_create_window_function are pointers to 5437 ** C-language callbacks that implement the new function. xStep and xFinal 5438 ** must both be non-NULL. xValue and xInverse may either both be NULL, in 5439 ** which case a regular aggregate function is created, or must both be 5440 ** non-NULL, in which case the new function may be used as either an aggregate 5441 ** or aggregate window function. More details regarding the implementation 5442 ** of aggregate window functions are 5443 ** [user-defined window functions|available here]. 5444 ** 5445 ** ^(If the final parameter to sqlite3_create_function_v2() or 5446 ** sqlite3_create_window_function() is not NULL, then it is destructor for 5447 ** the application data pointer. The destructor is invoked when the function 5448 ** is deleted, either by being overloaded or when the database connection 5449 ** closes.)^ ^The destructor is also invoked if the call to 5450 ** sqlite3_create_function_v2() fails. ^When the destructor callback is 5451 ** invoked, it is passed a single argument which is a copy of the application 5452 ** data pointer which was the fifth parameter to sqlite3_create_function_v2(). 5453 ** 5454 ** ^It is permitted to register multiple implementations of the same 5455 ** functions with the same name but with either differing numbers of 5456 ** arguments or differing preferred text encodings. ^SQLite will use 5457 ** the implementation that most closely matches the way in which the 5458 ** SQL function is used. ^A function implementation with a non-negative 5459 ** nArg parameter is a better match than a function implementation with 5460 ** a negative nArg. ^A function where the preferred text encoding 5461 ** matches the database encoding is a better 5462 ** match than a function where the encoding is different. 5463 ** ^A function where the encoding difference is between UTF16le and UTF16be 5464 ** is a closer match than a function where the encoding difference is 5465 ** between UTF8 and UTF16. 5466 ** 5467 ** ^Built-in functions may be overloaded by new application-defined functions. 5468 ** 5469 ** ^An application-defined function is permitted to call other 5470 ** SQLite interfaces. However, such calls must not 5471 ** close the database connection nor finalize or reset the prepared 5472 ** statement in which the function is running. 5473 */ 5474 SQLITE_API int sqlite3_create_function( 5475 sqlite3 *db, 5476 const char *zFunctionName, 5477 int nArg, 5478 int eTextRep, 5479 void *pApp, 5480 void (*xFunc)(sqlite3_context*,int,sqlite3_value**), 5481 void (*xStep)(sqlite3_context*,int,sqlite3_value**), 5482 void (*xFinal)(sqlite3_context*) 5483 ); 5484 SQLITE_API int sqlite3_create_function16( 5485 sqlite3 *db, 5486 const void *zFunctionName, 5487 int nArg, 5488 int eTextRep, 5489 void *pApp, 5490 void (*xFunc)(sqlite3_context*,int,sqlite3_value**), 5491 void (*xStep)(sqlite3_context*,int,sqlite3_value**), 5492 void (*xFinal)(sqlite3_context*) 5493 ); 5494 SQLITE_API int sqlite3_create_function_v2( 5495 sqlite3 *db, 5496 const char *zFunctionName, 5497 int nArg, 5498 int eTextRep, 5499 void *pApp, 5500 void (*xFunc)(sqlite3_context*,int,sqlite3_value**), 5501 void (*xStep)(sqlite3_context*,int,sqlite3_value**), 5502 void (*xFinal)(sqlite3_context*), 5503 void(*xDestroy)(void*) 5504 ); 5505 SQLITE_API int sqlite3_create_window_function( 5506 sqlite3 *db, 5507 const char *zFunctionName, 5508 int nArg, 5509 int eTextRep, 5510 void *pApp, 5511 void (*xStep)(sqlite3_context*,int,sqlite3_value**), 5512 void (*xFinal)(sqlite3_context*), 5513 void (*xValue)(sqlite3_context*), 5514 void (*xInverse)(sqlite3_context*,int,sqlite3_value**), 5515 void(*xDestroy)(void*) 5516 ); 5517 5518 /* 5519 ** CAPI3REF: Text Encodings 5520 ** 5521 ** These constant define integer codes that represent the various 5522 ** text encodings supported by SQLite. 5523 */ 5524 #define SQLITE_UTF8 1 /* IMP: R-37514-35566 */ 5525 #define SQLITE_UTF16LE 2 /* IMP: R-03371-37637 */ 5526 #define SQLITE_UTF16BE 3 /* IMP: R-51971-34154 */ 5527 #define SQLITE_UTF16 4 /* Use native byte order */ 5528 #define SQLITE_ANY 5 /* Deprecated */ 5529 #define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only */ 5530 5531 /* 5532 ** CAPI3REF: Function Flags 5533 ** 5534 ** These constants may be ORed together with the 5535 ** [SQLITE_UTF8 | preferred text encoding] as the fourth argument 5536 ** to [sqlite3_create_function()], [sqlite3_create_function16()], or 5537 ** [sqlite3_create_function_v2()]. 5538 ** 5539 ** <dl> 5540 ** [[SQLITE_DETERMINISTIC]] <dt>SQLITE_DETERMINISTIC</dt><dd> 5541 ** The SQLITE_DETERMINISTIC flag means that the new function always gives 5542 ** the same output when the input parameters are the same. 5543 ** The [abs|abs() function] is deterministic, for example, but 5544 ** [randomblob|randomblob()] is not. Functions must 5545 ** be deterministic in order to be used in certain contexts such as 5546 ** with the WHERE clause of [partial indexes] or in [generated columns]. 5547 ** SQLite might also optimize deterministic functions by factoring them 5548 ** out of inner loops. 5549 ** </dd> 5550 ** 5551 ** [[SQLITE_DIRECTONLY]] <dt>SQLITE_DIRECTONLY</dt><dd> 5552 ** The SQLITE_DIRECTONLY flag means that the function may only be invoked 5553 ** from top-level SQL, and cannot be used in VIEWs or TRIGGERs nor in 5554 ** schema structures such as [CHECK constraints], [DEFAULT clauses], 5555 ** [expression indexes], [partial indexes], or [generated columns]. 5556 ** <p> 5557 ** The SQLITE_DIRECTONLY flag is recommended for any 5558 ** [application-defined SQL function] 5559 ** that has side-effects or that could potentially leak sensitive information. 5560 ** This will prevent attacks in which an application is tricked 5561 ** into using a database file that has had its schema surreptitiously 5562 ** modified to invoke the application-defined function in ways that are 5563 ** harmful. 5564 ** <p> 5565 ** Some people say it is good practice to set SQLITE_DIRECTONLY on all 5566 ** [application-defined SQL functions], regardless of whether or not they 5567 ** are security sensitive, as doing so prevents those functions from being used 5568 ** inside of the database schema, and thus ensures that the database 5569 ** can be inspected and modified using generic tools (such as the [CLI]) 5570 ** that do not have access to the application-defined functions. 5571 ** </dd> 5572 ** 5573 ** [[SQLITE_INNOCUOUS]] <dt>SQLITE_INNOCUOUS</dt><dd> 5574 ** The SQLITE_INNOCUOUS flag means that the function is unlikely 5575 ** to cause problems even if misused. An innocuous function should have 5576 ** no side effects and should not depend on any values other than its 5577 ** input parameters. The [abs|abs() function] is an example of an 5578 ** innocuous function. 5579 ** The [load_extension() SQL function] is not innocuous because of its 5580 ** side effects. 5581 ** <p> SQLITE_INNOCUOUS is similar to SQLITE_DETERMINISTIC, but is not 5582 ** exactly the same. The [random|random() function] is an example of a 5583 ** function that is innocuous but not deterministic. 5584 ** <p>Some heightened security settings 5585 ** ([SQLITE_DBCONFIG_TRUSTED_SCHEMA] and [PRAGMA trusted_schema=OFF]) 5586 ** disable the use of SQL functions inside views and triggers and in 5587 ** schema structures such as [CHECK constraints], [DEFAULT clauses], 5588 ** [expression indexes], [partial indexes], and [generated columns] unless 5589 ** the function is tagged with SQLITE_INNOCUOUS. Most built-in functions 5590 ** are innocuous. Developers are advised to avoid using the 5591 ** SQLITE_INNOCUOUS flag for application-defined functions unless the 5592 ** function has been carefully audited and found to be free of potentially 5593 ** security-adverse side-effects and information-leaks. 5594 ** </dd> 5595 ** 5596 ** [[SQLITE_SUBTYPE]] <dt>SQLITE_SUBTYPE</dt><dd> 5597 ** The SQLITE_SUBTYPE flag indicates to SQLite that a function might call 5598 ** [sqlite3_value_subtype()] to inspect the sub-types of its arguments. 5599 ** This flag instructs SQLite to omit some corner-case optimizations that 5600 ** might disrupt the operation of the [sqlite3_value_subtype()] function, 5601 ** causing it to return zero rather than the correct subtype(). 5602 ** SQL functions that invokes [sqlite3_value_subtype()] should have this 5603 ** property. If the SQLITE_SUBTYPE property is omitted, then the return 5604 ** value from [sqlite3_value_subtype()] might sometimes be zero even though 5605 ** a non-zero subtype was specified by the function argument expression. 5606 ** 5607 ** [[SQLITE_RESULT_SUBTYPE]] <dt>SQLITE_RESULT_SUBTYPE</dt><dd> 5608 ** The SQLITE_RESULT_SUBTYPE flag indicates to SQLite that a function might call 5609 ** [sqlite3_result_subtype()] to cause a sub-type to be associated with its 5610 ** result. 5611 ** Every function that invokes [sqlite3_result_subtype()] should have this 5612 ** property. If it does not, then the call to [sqlite3_result_subtype()] 5613 ** might become a no-op if the function is used as term in an 5614 ** [expression index]. On the other hand, SQL functions that never invoke 5615 ** [sqlite3_result_subtype()] should avoid setting this property, as the 5616 ** purpose of this property is to disable certain optimizations that are 5617 ** incompatible with subtypes. 5618 ** </dd> 5619 ** </dl> 5620 */ 5621 #define SQLITE_DETERMINISTIC 0x000000800 5622 #define SQLITE_DIRECTONLY 0x000080000 5623 #define SQLITE_SUBTYPE 0x000100000 5624 #define SQLITE_INNOCUOUS 0x000200000 5625 #define SQLITE_RESULT_SUBTYPE 0x001000000 5626 5627 /* 5628 ** CAPI3REF: Deprecated Functions 5629 ** DEPRECATED 5630 ** 5631 ** These functions are [deprecated]. In order to maintain 5632 ** backwards compatibility with older code, these functions continue 5633 ** to be supported. However, new applications should avoid 5634 ** the use of these functions. To encourage programmers to avoid 5635 ** these functions, we will not explain what they do. 5636 */ 5637 #ifndef SQLITE_OMIT_DEPRECATED 5638 SQLITE_API SQLITE_DEPRECATED int sqlite3_aggregate_count(sqlite3_context*); 5639 SQLITE_API SQLITE_DEPRECATED int sqlite3_expired(sqlite3_stmt*); 5640 SQLITE_API SQLITE_DEPRECATED int sqlite3_transfer_bindings(sqlite3_stmt*, sqlite3_stmt*); 5641 SQLITE_API SQLITE_DEPRECATED int sqlite3_global_recover(void); 5642 SQLITE_API SQLITE_DEPRECATED void sqlite3_thread_cleanup(void); 5643 SQLITE_API SQLITE_DEPRECATED int sqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int), 5644 void*,sqlite3_int64); 5645 #endif 5646 5647 /* 5648 ** CAPI3REF: Obtaining SQL Values 5649 ** METHOD: sqlite3_value 5650 ** 5651 ** <b>Summary:</b> 5652 ** <blockquote><table border=0 cellpadding=0 cellspacing=0> 5653 ** <tr><td><b>sqlite3_value_blob</b><td>→<td>BLOB value 5654 ** <tr><td><b>sqlite3_value_double</b><td>→<td>REAL value 5655 ** <tr><td><b>sqlite3_value_int</b><td>→<td>32-bit INTEGER value 5656 ** <tr><td><b>sqlite3_value_int64</b><td>→<td>64-bit INTEGER value 5657 ** <tr><td><b>sqlite3_value_pointer</b><td>→<td>Pointer value 5658 ** <tr><td><b>sqlite3_value_text</b><td>→<td>UTF-8 TEXT value 5659 ** <tr><td><b>sqlite3_value_text16</b><td>→<td>UTF-16 TEXT value in 5660 ** the native byteorder 5661 ** <tr><td><b>sqlite3_value_text16be</b><td>→<td>UTF-16be TEXT value 5662 ** <tr><td><b>sqlite3_value_text16le</b><td>→<td>UTF-16le TEXT value 5663 ** <tr><td> <td> <td> 5664 ** <tr><td><b>sqlite3_value_bytes</b><td>→<td>Size of a BLOB 5665 ** or a UTF-8 TEXT in bytes 5666 ** <tr><td><b>sqlite3_value_bytes16 </b> 5667 ** <td>→ <td>Size of UTF-16 5668 ** TEXT in bytes 5669 ** <tr><td><b>sqlite3_value_type</b><td>→<td>Default 5670 ** datatype of the value 5671 ** <tr><td><b>sqlite3_value_numeric_type </b> 5672 ** <td>→ <td>Best numeric datatype of the value 5673 ** <tr><td><b>sqlite3_value_nochange </b> 5674 ** <td>→ <td>True if the column is unchanged in an UPDATE 5675 ** against a virtual table. 5676 ** <tr><td><b>sqlite3_value_frombind </b> 5677 ** <td>→ <td>True if value originated from a [bound parameter] 5678 ** </table></blockquote> 5679 ** 5680 ** <b>Details:</b> 5681 ** 5682 ** These routines extract type, size, and content information from 5683 ** [protected sqlite3_value] objects. Protected sqlite3_value objects 5684 ** are used to pass parameter information into the functions that 5685 ** implement [application-defined SQL functions] and [virtual tables]. 5686 ** 5687 ** These routines work only with [protected sqlite3_value] objects. 5688 ** Any attempt to use these routines on an [unprotected sqlite3_value] 5689 ** is not threadsafe. 5690 ** 5691 ** ^These routines work just like the corresponding [column access functions] 5692 ** except that these routines take a single [protected sqlite3_value] object 5693 ** pointer instead of a [sqlite3_stmt*] pointer and an integer column number. 5694 ** 5695 ** ^The sqlite3_value_text16() interface extracts a UTF-16 string 5696 ** in the native byte-order of the host machine. ^The 5697 ** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces 5698 ** extract UTF-16 strings as big-endian and little-endian respectively. 5699 ** 5700 ** ^If [sqlite3_value] object V was initialized 5701 ** using [sqlite3_bind_pointer(S,I,P,X,D)] or [sqlite3_result_pointer(C,P,X,D)] 5702 ** and if X and Y are strings that compare equal according to strcmp(X,Y), 5703 ** then sqlite3_value_pointer(V,Y) will return the pointer P. ^Otherwise, 5704 ** sqlite3_value_pointer(V,Y) returns a NULL. The sqlite3_bind_pointer() 5705 ** routine is part of the [pointer passing interface] added for SQLite 3.20.0. 5706 ** 5707 ** ^(The sqlite3_value_type(V) interface returns the 5708 ** [SQLITE_INTEGER | datatype code] for the initial datatype of the 5709 ** [sqlite3_value] object V. The returned value is one of [SQLITE_INTEGER], 5710 ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].)^ 5711 ** Other interfaces might change the datatype for an sqlite3_value object. 5712 ** For example, if the datatype is initially SQLITE_INTEGER and 5713 ** sqlite3_value_text(V) is called to extract a text value for that 5714 ** integer, then subsequent calls to sqlite3_value_type(V) might return 5715 ** SQLITE_TEXT. Whether or not a persistent internal datatype conversion 5716 ** occurs is undefined and may change from one release of SQLite to the next. 5717 ** 5718 ** ^(The sqlite3_value_numeric_type() interface attempts to apply 5719 ** numeric affinity to the value. This means that an attempt is 5720 ** made to convert the value to an integer or floating point. If 5721 ** such a conversion is possible without loss of information (in other 5722 ** words, if the value is a string that looks like a number) 5723 ** then the conversion is performed. Otherwise no conversion occurs. 5724 ** The [SQLITE_INTEGER | datatype] after conversion is returned.)^ 5725 ** 5726 ** ^Within the [xUpdate] method of a [virtual table], the 5727 ** sqlite3_value_nochange(X) interface returns true if and only if 5728 ** the column corresponding to X is unchanged by the UPDATE operation 5729 ** that the xUpdate method call was invoked to implement and if 5730 ** and the prior [xColumn] method call that was invoked to extracted 5731 ** the value for that column returned without setting a result (probably 5732 ** because it queried [sqlite3_vtab_nochange()] and found that the column 5733 ** was unchanging). ^Within an [xUpdate] method, any value for which 5734 ** sqlite3_value_nochange(X) is true will in all other respects appear 5735 ** to be a NULL value. If sqlite3_value_nochange(X) is invoked anywhere other 5736 ** than within an [xUpdate] method call for an UPDATE statement, then 5737 ** the return value is arbitrary and meaningless. 5738 ** 5739 ** ^The sqlite3_value_frombind(X) interface returns non-zero if the 5740 ** value X originated from one of the [sqlite3_bind_int|sqlite3_bind()] 5741 ** interfaces. ^If X comes from an SQL literal value, or a table column, 5742 ** or an expression, then sqlite3_value_frombind(X) returns zero. 5743 ** 5744 ** Please pay particular attention to the fact that the pointer returned 5745 ** from [sqlite3_value_blob()], [sqlite3_value_text()], or 5746 ** [sqlite3_value_text16()] can be invalidated by a subsequent call to 5747 ** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()], 5748 ** or [sqlite3_value_text16()]. 5749 ** 5750 ** These routines must be called from the same thread as 5751 ** the SQL function that supplied the [sqlite3_value*] parameters. 5752 ** 5753 ** As long as the input parameter is correct, these routines can only 5754 ** fail if an out-of-memory error occurs during a format conversion. 5755 ** Only the following subset of interfaces are subject to out-of-memory 5756 ** errors: 5757 ** 5758 ** <ul> 5759 ** <li> sqlite3_value_blob() 5760 ** <li> sqlite3_value_text() 5761 ** <li> sqlite3_value_text16() 5762 ** <li> sqlite3_value_text16le() 5763 ** <li> sqlite3_value_text16be() 5764 ** <li> sqlite3_value_bytes() 5765 ** <li> sqlite3_value_bytes16() 5766 ** </ul> 5767 ** 5768 ** If an out-of-memory error occurs, then the return value from these 5769 ** routines is the same as if the column had contained an SQL NULL value. 5770 ** Valid SQL NULL returns can be distinguished from out-of-memory errors 5771 ** by invoking the [sqlite3_errcode()] immediately after the suspect 5772 ** return value is obtained and before any 5773 ** other SQLite interface is called on the same [database connection]. 5774 */ 5775 SQLITE_API const void *sqlite3_value_blob(sqlite3_value*); 5776 SQLITE_API double sqlite3_value_double(sqlite3_value*); 5777 SQLITE_API int sqlite3_value_int(sqlite3_value*); 5778 SQLITE_API sqlite3_int64 sqlite3_value_int64(sqlite3_value*); 5779 SQLITE_API void *sqlite3_value_pointer(sqlite3_value*, const char*); 5780 SQLITE_API const unsigned char *sqlite3_value_text(sqlite3_value*); 5781 SQLITE_API const void *sqlite3_value_text16(sqlite3_value*); 5782 SQLITE_API const void *sqlite3_value_text16le(sqlite3_value*); 5783 SQLITE_API const void *sqlite3_value_text16be(sqlite3_value*); 5784 SQLITE_API int sqlite3_value_bytes(sqlite3_value*); 5785 SQLITE_API int sqlite3_value_bytes16(sqlite3_value*); 5786 SQLITE_API int sqlite3_value_type(sqlite3_value*); 5787 SQLITE_API int sqlite3_value_numeric_type(sqlite3_value*); 5788 SQLITE_API int sqlite3_value_nochange(sqlite3_value*); 5789 SQLITE_API int sqlite3_value_frombind(sqlite3_value*); 5790 5791 /* 5792 ** CAPI3REF: Report the internal text encoding state of an sqlite3_value object 5793 ** METHOD: sqlite3_value 5794 ** 5795 ** ^(The sqlite3_value_encoding(X) interface returns one of [SQLITE_UTF8], 5796 ** [SQLITE_UTF16BE], or [SQLITE_UTF16LE] according to the current text encoding 5797 ** of the value X, assuming that X has type TEXT.)^ If sqlite3_value_type(X) 5798 ** returns something other than SQLITE_TEXT, then the return value from 5799 ** sqlite3_value_encoding(X) is meaningless. ^Calls to 5800 ** [sqlite3_value_text(X)], [sqlite3_value_text16(X)], [sqlite3_value_text16be(X)], 5801 ** [sqlite3_value_text16le(X)], [sqlite3_value_bytes(X)], or 5802 ** [sqlite3_value_bytes16(X)] might change the encoding of the value X and 5803 ** thus change the return from subsequent calls to sqlite3_value_encoding(X). 5804 ** 5805 ** This routine is intended for used by applications that test and validate 5806 ** the SQLite implementation. This routine is inquiring about the opaque 5807 ** internal state of an [sqlite3_value] object. Ordinary applications should 5808 ** not need to know what the internal state of an sqlite3_value object is and 5809 ** hence should not need to use this interface. 5810 */ 5811 SQLITE_API int sqlite3_value_encoding(sqlite3_value*); 5812 5813 /* 5814 ** CAPI3REF: Finding The Subtype Of SQL Values 5815 ** METHOD: sqlite3_value 5816 ** 5817 ** The sqlite3_value_subtype(V) function returns the subtype for 5818 ** an [application-defined SQL function] argument V. The subtype 5819 ** information can be used to pass a limited amount of context from 5820 ** one SQL function to another. Use the [sqlite3_result_subtype()] 5821 ** routine to set the subtype for the return value of an SQL function. 5822 ** 5823 ** Every [application-defined SQL function] that invoke this interface 5824 ** should include the [SQLITE_SUBTYPE] property in the text 5825 ** encoding argument when the function is [sqlite3_create_function|registered]. 5826 ** If the [SQLITE_SUBTYPE] property is omitted, then sqlite3_value_subtype() 5827 ** might return zero instead of the upstream subtype in some corner cases. 5828 */ 5829 SQLITE_API unsigned int sqlite3_value_subtype(sqlite3_value*); 5830 5831 /* 5832 ** CAPI3REF: Copy And Free SQL Values 5833 ** METHOD: sqlite3_value 5834 ** 5835 ** ^The sqlite3_value_dup(V) interface makes a copy of the [sqlite3_value] 5836 ** object D and returns a pointer to that copy. ^The [sqlite3_value] returned 5837 ** is a [protected sqlite3_value] object even if the input is not. 5838 ** ^The sqlite3_value_dup(V) interface returns NULL if V is NULL or if a 5839 ** memory allocation fails. ^If V is a [pointer value], then the result 5840 ** of sqlite3_value_dup(V) is a NULL value. 5841 ** 5842 ** ^The sqlite3_value_free(V) interface frees an [sqlite3_value] object 5843 ** previously obtained from [sqlite3_value_dup()]. ^If V is a NULL pointer 5844 ** then sqlite3_value_free(V) is a harmless no-op. 5845 */ 5846 SQLITE_API sqlite3_value *sqlite3_value_dup(const sqlite3_value*); 5847 SQLITE_API void sqlite3_value_free(sqlite3_value*); 5848 5849 /* 5850 ** CAPI3REF: Obtain Aggregate Function Context 5851 ** METHOD: sqlite3_context 5852 ** 5853 ** Implementations of aggregate SQL functions use this 5854 ** routine to allocate memory for storing their state. 5855 ** 5856 ** ^The first time the sqlite3_aggregate_context(C,N) routine is called 5857 ** for a particular aggregate function, SQLite allocates 5858 ** N bytes of memory, zeroes out that memory, and returns a pointer 5859 ** to the new memory. ^On second and subsequent calls to 5860 ** sqlite3_aggregate_context() for the same aggregate function instance, 5861 ** the same buffer is returned. Sqlite3_aggregate_context() is normally 5862 ** called once for each invocation of the xStep callback and then one 5863 ** last time when the xFinal callback is invoked. ^(When no rows match 5864 ** an aggregate query, the xStep() callback of the aggregate function 5865 ** implementation is never called and xFinal() is called exactly once. 5866 ** In those cases, sqlite3_aggregate_context() might be called for the 5867 ** first time from within xFinal().)^ 5868 ** 5869 ** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer 5870 ** when first called if N is less than or equal to zero or if a memory 5871 ** allocation error occurs. 5872 ** 5873 ** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is 5874 ** determined by the N parameter on first successful call. Changing the 5875 ** value of N in any subsequent call to sqlite3_aggregate_context() within 5876 ** the same aggregate function instance will not resize the memory 5877 ** allocation.)^ Within the xFinal callback, it is customary to set 5878 ** N=0 in calls to sqlite3_aggregate_context(C,N) so that no 5879 ** pointless memory allocations occur. 5880 ** 5881 ** ^SQLite automatically frees the memory allocated by 5882 ** sqlite3_aggregate_context() when the aggregate query concludes. 5883 ** 5884 ** The first parameter must be a copy of the 5885 ** [sqlite3_context | SQL function context] that is the first parameter 5886 ** to the xStep or xFinal callback routine that implements the aggregate 5887 ** function. 5888 ** 5889 ** This routine must be called from the same thread in which 5890 ** the aggregate SQL function is running. 5891 */ 5892 SQLITE_API void *sqlite3_aggregate_context(sqlite3_context*, int nBytes); 5893 5894 /* 5895 ** CAPI3REF: User Data For Functions 5896 ** METHOD: sqlite3_context 5897 ** 5898 ** ^The sqlite3_user_data() interface returns a copy of 5899 ** the pointer that was the pUserData parameter (the 5th parameter) 5900 ** of the [sqlite3_create_function()] 5901 ** and [sqlite3_create_function16()] routines that originally 5902 ** registered the application defined function. 5903 ** 5904 ** This routine must be called from the same thread in which 5905 ** the application-defined function is running. 5906 */ 5907 SQLITE_API void *sqlite3_user_data(sqlite3_context*); 5908 5909 /* 5910 ** CAPI3REF: Database Connection For Functions 5911 ** METHOD: sqlite3_context 5912 ** 5913 ** ^The sqlite3_context_db_handle() interface returns a copy of 5914 ** the pointer to the [database connection] (the 1st parameter) 5915 ** of the [sqlite3_create_function()] 5916 ** and [sqlite3_create_function16()] routines that originally 5917 ** registered the application defined function. 5918 */ 5919 SQLITE_API sqlite3 *sqlite3_context_db_handle(sqlite3_context*); 5920 5921 /* 5922 ** CAPI3REF: Function Auxiliary Data 5923 ** METHOD: sqlite3_context 5924 ** 5925 ** These functions may be used by (non-aggregate) SQL functions to 5926 ** associate auxiliary data with argument values. If the same argument 5927 ** value is passed to multiple invocations of the same SQL function during 5928 ** query execution, under some circumstances the associated auxiliary data 5929 ** might be preserved. An example of where this might be useful is in a 5930 ** regular-expression matching function. The compiled version of the regular 5931 ** expression can be stored as auxiliary data associated with the pattern string. 5932 ** Then as long as the pattern string remains the same, 5933 ** the compiled regular expression can be reused on multiple 5934 ** invocations of the same function. 5935 ** 5936 ** ^The sqlite3_get_auxdata(C,N) interface returns a pointer to the auxiliary data 5937 ** associated by the sqlite3_set_auxdata(C,N,P,X) function with the Nth argument 5938 ** value to the application-defined function. ^N is zero for the left-most 5939 ** function argument. ^If there is no auxiliary data 5940 ** associated with the function argument, the sqlite3_get_auxdata(C,N) interface 5941 ** returns a NULL pointer. 5942 ** 5943 ** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as auxiliary data for the 5944 ** N-th argument of the application-defined function. ^Subsequent 5945 ** calls to sqlite3_get_auxdata(C,N) return P from the most recent 5946 ** sqlite3_set_auxdata(C,N,P,X) call if the auxiliary data is still valid or 5947 ** NULL if the auxiliary data has been discarded. 5948 ** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL, 5949 ** SQLite will invoke the destructor function X with parameter P exactly 5950 ** once, when the auxiliary data is discarded. 5951 ** SQLite is free to discard the auxiliary data at any time, including: <ul> 5952 ** <li> ^(when the corresponding function parameter changes)^, or 5953 ** <li> ^(when [sqlite3_reset()] or [sqlite3_finalize()] is called for the 5954 ** SQL statement)^, or 5955 ** <li> ^(when sqlite3_set_auxdata() is invoked again on the same 5956 ** parameter)^, or 5957 ** <li> ^(during the original sqlite3_set_auxdata() call when a memory 5958 ** allocation error occurs.)^ 5959 ** <li> ^(during the original sqlite3_set_auxdata() call if the function 5960 ** is evaluated during query planning instead of during query execution, 5961 ** as sometimes happens with [SQLITE_ENABLE_STAT4].)^ </ul> 5962 ** 5963 ** Note the last two bullets in particular. The destructor X in 5964 ** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the 5965 ** sqlite3_set_auxdata() interface even returns. Hence sqlite3_set_auxdata() 5966 ** should be called near the end of the function implementation and the 5967 ** function implementation should not make any use of P after 5968 ** sqlite3_set_auxdata() has been called. Furthermore, a call to 5969 ** sqlite3_get_auxdata() that occurs immediately after a corresponding call 5970 ** to sqlite3_set_auxdata() might still return NULL if an out-of-memory 5971 ** condition occurred during the sqlite3_set_auxdata() call or if the 5972 ** function is being evaluated during query planning rather than during 5973 ** query execution. 5974 ** 5975 ** ^(In practice, auxiliary data is preserved between function calls for 5976 ** function parameters that are compile-time constants, including literal 5977 ** values and [parameters] and expressions composed from the same.)^ 5978 ** 5979 ** The value of the N parameter to these interfaces should be non-negative. 5980 ** Future enhancements may make use of negative N values to define new 5981 ** kinds of function caching behavior. 5982 ** 5983 ** These routines must be called from the same thread in which 5984 ** the SQL function is running. 5985 ** 5986 ** See also: [sqlite3_get_clientdata()] and [sqlite3_set_clientdata()]. 5987 */ 5988 SQLITE_API void *sqlite3_get_auxdata(sqlite3_context*, int N); 5989 SQLITE_API void sqlite3_set_auxdata(sqlite3_context*, int N, void*, void (*)(void*)); 5990 5991 /* 5992 ** CAPI3REF: Database Connection Client Data 5993 ** METHOD: sqlite3 5994 ** 5995 ** These functions are used to associate one or more named pointers 5996 ** with a [database connection]. 5997 ** A call to sqlite3_set_clientdata(D,N,P,X) causes the pointer P 5998 ** to be attached to [database connection] D using name N. Subsequent 5999 ** calls to sqlite3_get_clientdata(D,N) will return a copy of pointer P 6000 ** or a NULL pointer if there were no prior calls to 6001 ** sqlite3_set_clientdata() with the same values of D and N. 6002 ** Names are compared using strcmp() and are thus case sensitive. 6003 ** 6004 ** If P and X are both non-NULL, then the destructor X is invoked with 6005 ** argument P on the first of the following occurrences: 6006 ** <ul> 6007 ** <li> An out-of-memory error occurs during the call to 6008 ** sqlite3_set_clientdata() which attempts to register pointer P. 6009 ** <li> A subsequent call to sqlite3_set_clientdata(D,N,P,X) is made 6010 ** with the same D and N parameters. 6011 ** <li> The database connection closes. SQLite does not make any guarantees 6012 ** about the order in which destructors are called, only that all 6013 ** destructors will be called exactly once at some point during the 6014 ** database connection closing process. 6015 ** </ul> 6016 ** 6017 ** SQLite does not do anything with client data other than invoke 6018 ** destructors on the client data at the appropriate time. The intended 6019 ** use for client data is to provide a mechanism for wrapper libraries 6020 ** to store additional information about an SQLite database connection. 6021 ** 6022 ** There is no limit (other than available memory) on the number of different 6023 ** client data pointers (with different names) that can be attached to a 6024 ** single database connection. However, the implementation is optimized 6025 ** for the case of having only one or two different client data names. 6026 ** Applications and wrapper libraries are discouraged from using more than 6027 ** one client data name each. 6028 ** 6029 ** There is no way to enumerate the client data pointers 6030 ** associated with a database connection. The N parameter can be thought 6031 ** of as a secret key such that only code that knows the secret key is able 6032 ** to access the associated data. 6033 ** 6034 ** Security Warning: These interfaces should not be exposed in scripting 6035 ** languages or in other circumstances where it might be possible for an 6036 ** an attacker to invoke them. Any agent that can invoke these interfaces 6037 ** can probably also take control of the process. 6038 ** 6039 ** Database connection client data is only available for SQLite 6040 ** version 3.44.0 ([dateof:3.44.0]) and later. 6041 ** 6042 ** See also: [sqlite3_set_auxdata()] and [sqlite3_get_auxdata()]. 6043 */ 6044 SQLITE_API void *sqlite3_get_clientdata(sqlite3*,const char*); 6045 SQLITE_API int sqlite3_set_clientdata(sqlite3*, const char*, void*, void(*)(void*)); 6046 6047 /* 6048 ** CAPI3REF: Constants Defining Special Destructor Behavior 6049 ** 6050 ** These are special values for the destructor that is passed in as the 6051 ** final argument to routines like [sqlite3_result_blob()]. ^If the destructor 6052 ** argument is SQLITE_STATIC, it means that the content pointer is constant 6053 ** and will never change. It does not need to be destroyed. ^The 6054 ** SQLITE_TRANSIENT value means that the content will likely change in 6055 ** the near future and that SQLite should make its own private copy of 6056 ** the content before returning. 6057 ** 6058 ** The typedef is necessary to work around problems in certain 6059 ** C++ compilers. 6060 */ 6061 typedef void (*sqlite3_destructor_type)(void*); 6062 #define SQLITE_STATIC ((sqlite3_destructor_type)0) 6063 #define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1) 6064 6065 /* 6066 ** CAPI3REF: Setting The Result Of An SQL Function 6067 ** METHOD: sqlite3_context 6068 ** 6069 ** These routines are used by the xFunc or xFinal callbacks that 6070 ** implement SQL functions and aggregates. See 6071 ** [sqlite3_create_function()] and [sqlite3_create_function16()] 6072 ** for additional information. 6073 ** 6074 ** These functions work very much like the [parameter binding] family of 6075 ** functions used to bind values to host parameters in prepared statements. 6076 ** Refer to the [SQL parameter] documentation for additional information. 6077 ** 6078 ** ^The sqlite3_result_blob() interface sets the result from 6079 ** an application-defined function to be the BLOB whose content is pointed 6080 ** to by the second parameter and which is N bytes long where N is the 6081 ** third parameter. 6082 ** 6083 ** ^The sqlite3_result_zeroblob(C,N) and sqlite3_result_zeroblob64(C,N) 6084 ** interfaces set the result of the application-defined function to be 6085 ** a BLOB containing all zero bytes and N bytes in size. 6086 ** 6087 ** ^The sqlite3_result_double() interface sets the result from 6088 ** an application-defined function to be a floating point value specified 6089 ** by its 2nd argument. 6090 ** 6091 ** ^The sqlite3_result_error() and sqlite3_result_error16() functions 6092 ** cause the implemented SQL function to throw an exception. 6093 ** ^SQLite uses the string pointed to by the 6094 ** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16() 6095 ** as the text of an error message. ^SQLite interprets the error 6096 ** message string from sqlite3_result_error() as UTF-8. ^SQLite 6097 ** interprets the string from sqlite3_result_error16() as UTF-16 using 6098 ** the same [byte-order determination rules] as [sqlite3_bind_text16()]. 6099 ** ^If the third parameter to sqlite3_result_error() 6100 ** or sqlite3_result_error16() is negative then SQLite takes as the error 6101 ** message all text up through the first zero character. 6102 ** ^If the third parameter to sqlite3_result_error() or 6103 ** sqlite3_result_error16() is non-negative then SQLite takes that many 6104 ** bytes (not characters) from the 2nd parameter as the error message. 6105 ** ^The sqlite3_result_error() and sqlite3_result_error16() 6106 ** routines make a private copy of the error message text before 6107 ** they return. Hence, the calling function can deallocate or 6108 ** modify the text after they return without harm. 6109 ** ^The sqlite3_result_error_code() function changes the error code 6110 ** returned by SQLite as a result of an error in a function. ^By default, 6111 ** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error() 6112 ** or sqlite3_result_error16() resets the error code to SQLITE_ERROR. 6113 ** 6114 ** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an 6115 ** error indicating that a string or BLOB is too long to represent. 6116 ** 6117 ** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an 6118 ** error indicating that a memory allocation failed. 6119 ** 6120 ** ^The sqlite3_result_int() interface sets the return value 6121 ** of the application-defined function to be the 32-bit signed integer 6122 ** value given in the 2nd argument. 6123 ** ^The sqlite3_result_int64() interface sets the return value 6124 ** of the application-defined function to be the 64-bit signed integer 6125 ** value given in the 2nd argument. 6126 ** 6127 ** ^The sqlite3_result_null() interface sets the return value 6128 ** of the application-defined function to be NULL. 6129 ** 6130 ** ^The sqlite3_result_text(), sqlite3_result_text16(), 6131 ** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces 6132 ** set the return value of the application-defined function to be 6133 ** a text string which is represented as UTF-8, UTF-16 native byte order, 6134 ** UTF-16 little endian, or UTF-16 big endian, respectively. 6135 ** ^The sqlite3_result_text64() interface sets the return value of an 6136 ** application-defined function to be a text string in an encoding 6137 ** specified by the fifth (and last) parameter, which must be one 6138 ** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE]. 6139 ** ^SQLite takes the text result from the application from 6140 ** the 2nd parameter of the sqlite3_result_text* interfaces. 6141 ** ^If the 3rd parameter to any of the sqlite3_result_text* interfaces 6142 ** other than sqlite3_result_text64() is negative, then SQLite computes 6143 ** the string length itself by searching the 2nd parameter for the first 6144 ** zero character. 6145 ** ^If the 3rd parameter to the sqlite3_result_text* interfaces 6146 ** is non-negative, then as many bytes (not characters) of the text 6147 ** pointed to by the 2nd parameter are taken as the application-defined 6148 ** function result. If the 3rd parameter is non-negative, then it 6149 ** must be the byte offset into the string where the NUL terminator would 6150 ** appear if the string where NUL terminated. If any NUL characters occur 6151 ** in the string at a byte offset that is less than the value of the 3rd 6152 ** parameter, then the resulting string will contain embedded NULs and the 6153 ** result of expressions operating on strings with embedded NULs is undefined. 6154 ** ^If the 4th parameter to the sqlite3_result_text* interfaces 6155 ** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that 6156 ** function as the destructor on the text or BLOB result when it has 6157 ** finished using that result. 6158 ** ^If the 4th parameter to the sqlite3_result_text* interfaces or to 6159 ** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite 6160 ** assumes that the text or BLOB result is in constant space and does not 6161 ** copy the content of the parameter nor call a destructor on the content 6162 ** when it has finished using that result. 6163 ** ^If the 4th parameter to the sqlite3_result_text* interfaces 6164 ** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT 6165 ** then SQLite makes a copy of the result into space obtained 6166 ** from [sqlite3_malloc()] before it returns. 6167 ** 6168 ** ^For the sqlite3_result_text16(), sqlite3_result_text16le(), and 6169 ** sqlite3_result_text16be() routines, and for sqlite3_result_text64() 6170 ** when the encoding is not UTF8, if the input UTF16 begins with a 6171 ** byte-order mark (BOM, U+FEFF) then the BOM is removed from the 6172 ** string and the rest of the string is interpreted according to the 6173 ** byte-order specified by the BOM. ^The byte-order specified by 6174 ** the BOM at the beginning of the text overrides the byte-order 6175 ** specified by the interface procedure. ^So, for example, if 6176 ** sqlite3_result_text16le() is invoked with text that begins 6177 ** with bytes 0xfe, 0xff (a big-endian byte-order mark) then the 6178 ** first two bytes of input are skipped and the remaining input 6179 ** is interpreted as UTF16BE text. 6180 ** 6181 ** ^For UTF16 input text to the sqlite3_result_text16(), 6182 ** sqlite3_result_text16be(), sqlite3_result_text16le(), and 6183 ** sqlite3_result_text64() routines, if the text contains invalid 6184 ** UTF16 characters, the invalid characters might be converted 6185 ** into the unicode replacement character, U+FFFD. 6186 ** 6187 ** ^The sqlite3_result_value() interface sets the result of 6188 ** the application-defined function to be a copy of the 6189 ** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The 6190 ** sqlite3_result_value() interface makes a copy of the [sqlite3_value] 6191 ** so that the [sqlite3_value] specified in the parameter may change or 6192 ** be deallocated after sqlite3_result_value() returns without harm. 6193 ** ^A [protected sqlite3_value] object may always be used where an 6194 ** [unprotected sqlite3_value] object is required, so either 6195 ** kind of [sqlite3_value] object can be used with this interface. 6196 ** 6197 ** ^The sqlite3_result_pointer(C,P,T,D) interface sets the result to an 6198 ** SQL NULL value, just like [sqlite3_result_null(C)], except that it 6199 ** also associates the host-language pointer P or type T with that 6200 ** NULL value such that the pointer can be retrieved within an 6201 ** [application-defined SQL function] using [sqlite3_value_pointer()]. 6202 ** ^If the D parameter is not NULL, then it is a pointer to a destructor 6203 ** for the P parameter. ^SQLite invokes D with P as its only argument 6204 ** when SQLite is finished with P. The T parameter should be a static 6205 ** string and preferably a string literal. The sqlite3_result_pointer() 6206 ** routine is part of the [pointer passing interface] added for SQLite 3.20.0. 6207 ** 6208 ** If these routines are called from within the different thread 6209 ** than the one containing the application-defined function that received 6210 ** the [sqlite3_context] pointer, the results are undefined. 6211 */ 6212 SQLITE_API void sqlite3_result_blob(sqlite3_context*, const void*, int, void(*)(void*)); 6213 SQLITE_API void sqlite3_result_blob64(sqlite3_context*,const void*, 6214 sqlite3_uint64,void(*)(void*)); 6215 SQLITE_API void sqlite3_result_double(sqlite3_context*, double); 6216 SQLITE_API void sqlite3_result_error(sqlite3_context*, const char*, int); 6217 SQLITE_API void sqlite3_result_error16(sqlite3_context*, const void*, int); 6218 SQLITE_API void sqlite3_result_error_toobig(sqlite3_context*); 6219 SQLITE_API void sqlite3_result_error_nomem(sqlite3_context*); 6220 SQLITE_API void sqlite3_result_error_code(sqlite3_context*, int); 6221 SQLITE_API void sqlite3_result_int(sqlite3_context*, int); 6222 SQLITE_API void sqlite3_result_int64(sqlite3_context*, sqlite3_int64); 6223 SQLITE_API void sqlite3_result_null(sqlite3_context*); 6224 SQLITE_API void sqlite3_result_text(sqlite3_context*, const char*, int, void(*)(void*)); 6225 SQLITE_API void sqlite3_result_text64(sqlite3_context*, const char*,sqlite3_uint64, 6226 void(*)(void*), unsigned char encoding); 6227 SQLITE_API void sqlite3_result_text16(sqlite3_context*, const void*, int, void(*)(void*)); 6228 SQLITE_API void sqlite3_result_text16le(sqlite3_context*, const void*, int,void(*)(void*)); 6229 SQLITE_API void sqlite3_result_text16be(sqlite3_context*, const void*, int,void(*)(void*)); 6230 SQLITE_API void sqlite3_result_value(sqlite3_context*, sqlite3_value*); 6231 SQLITE_API void sqlite3_result_pointer(sqlite3_context*, void*,const char*,void(*)(void*)); 6232 SQLITE_API void sqlite3_result_zeroblob(sqlite3_context*, int n); 6233 SQLITE_API int sqlite3_result_zeroblob64(sqlite3_context*, sqlite3_uint64 n); 6234 6235 6236 /* 6237 ** CAPI3REF: Setting The Subtype Of An SQL Function 6238 ** METHOD: sqlite3_context 6239 ** 6240 ** The sqlite3_result_subtype(C,T) function causes the subtype of 6241 ** the result from the [application-defined SQL function] with 6242 ** [sqlite3_context] C to be the value T. Only the lower 8 bits 6243 ** of the subtype T are preserved in current versions of SQLite; 6244 ** higher order bits are discarded. 6245 ** The number of subtype bytes preserved by SQLite might increase 6246 ** in future releases of SQLite. 6247 ** 6248 ** Every [application-defined SQL function] that invokes this interface 6249 ** should include the [SQLITE_RESULT_SUBTYPE] property in its 6250 ** text encoding argument when the SQL function is 6251 ** [sqlite3_create_function|registered]. If the [SQLITE_RESULT_SUBTYPE] 6252 ** property is omitted from the function that invokes sqlite3_result_subtype(), 6253 ** then in some cases the sqlite3_result_subtype() might fail to set 6254 ** the result subtype. 6255 ** 6256 ** If SQLite is compiled with -DSQLITE_STRICT_SUBTYPE=1, then any 6257 ** SQL function that invokes the sqlite3_result_subtype() interface 6258 ** and that does not have the SQLITE_RESULT_SUBTYPE property will raise 6259 ** an error. Future versions of SQLite might enable -DSQLITE_STRICT_SUBTYPE=1 6260 ** by default. 6261 */ 6262 SQLITE_API void sqlite3_result_subtype(sqlite3_context*,unsigned int); 6263 6264 /* 6265 ** CAPI3REF: Define New Collating Sequences 6266 ** METHOD: sqlite3 6267 ** 6268 ** ^These functions add, remove, or modify a [collation] associated 6269 ** with the [database connection] specified as the first argument. 6270 ** 6271 ** ^The name of the collation is a UTF-8 string 6272 ** for sqlite3_create_collation() and sqlite3_create_collation_v2() 6273 ** and a UTF-16 string in native byte order for sqlite3_create_collation16(). 6274 ** ^Collation names that compare equal according to [sqlite3_strnicmp()] are 6275 ** considered to be the same name. 6276 ** 6277 ** ^(The third argument (eTextRep) must be one of the constants: 6278 ** <ul> 6279 ** <li> [SQLITE_UTF8], 6280 ** <li> [SQLITE_UTF16LE], 6281 ** <li> [SQLITE_UTF16BE], 6282 ** <li> [SQLITE_UTF16], or 6283 ** <li> [SQLITE_UTF16_ALIGNED]. 6284 ** </ul>)^ 6285 ** ^The eTextRep argument determines the encoding of strings passed 6286 ** to the collating function callback, xCompare. 6287 ** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep 6288 ** force strings to be UTF16 with native byte order. 6289 ** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin 6290 ** on an even byte address. 6291 ** 6292 ** ^The fourth argument, pArg, is an application data pointer that is passed 6293 ** through as the first argument to the collating function callback. 6294 ** 6295 ** ^The fifth argument, xCompare, is a pointer to the collating function. 6296 ** ^Multiple collating functions can be registered using the same name but 6297 ** with different eTextRep parameters and SQLite will use whichever 6298 ** function requires the least amount of data transformation. 6299 ** ^If the xCompare argument is NULL then the collating function is 6300 ** deleted. ^When all collating functions having the same name are deleted, 6301 ** that collation is no longer usable. 6302 ** 6303 ** ^The collating function callback is invoked with a copy of the pArg 6304 ** application data pointer and with two strings in the encoding specified 6305 ** by the eTextRep argument. The two integer parameters to the collating 6306 ** function callback are the length of the two strings, in bytes. The collating 6307 ** function must return an integer that is negative, zero, or positive 6308 ** if the first string is less than, equal to, or greater than the second, 6309 ** respectively. A collating function must always return the same answer 6310 ** given the same inputs. If two or more collating functions are registered 6311 ** to the same collation name (using different eTextRep values) then all 6312 ** must give an equivalent answer when invoked with equivalent strings. 6313 ** The collating function must obey the following properties for all 6314 ** strings A, B, and C: 6315 ** 6316 ** <ol> 6317 ** <li> If A==B then B==A. 6318 ** <li> If A==B and B==C then A==C. 6319 ** <li> If A<B THEN B>A. 6320 ** <li> If A<B and B<C then A<C. 6321 ** </ol> 6322 ** 6323 ** If a collating function fails any of the above constraints and that 6324 ** collating function is registered and used, then the behavior of SQLite 6325 ** is undefined. 6326 ** 6327 ** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation() 6328 ** with the addition that the xDestroy callback is invoked on pArg when 6329 ** the collating function is deleted. 6330 ** ^Collating functions are deleted when they are overridden by later 6331 ** calls to the collation creation functions or when the 6332 ** [database connection] is closed using [sqlite3_close()]. 6333 ** 6334 ** ^The xDestroy callback is <u>not</u> called if the 6335 ** sqlite3_create_collation_v2() function fails. Applications that invoke 6336 ** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should 6337 ** check the return code and dispose of the application data pointer 6338 ** themselves rather than expecting SQLite to deal with it for them. 6339 ** This is different from every other SQLite interface. The inconsistency 6340 ** is unfortunate but cannot be changed without breaking backwards 6341 ** compatibility. 6342 ** 6343 ** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()]. 6344 */ 6345 SQLITE_API int sqlite3_create_collation( 6346 sqlite3*, 6347 const char *zName, 6348 int eTextRep, 6349 void *pArg, 6350 int(*xCompare)(void*,int,const void*,int,const void*) 6351 ); 6352 SQLITE_API int sqlite3_create_collation_v2( 6353 sqlite3*, 6354 const char *zName, 6355 int eTextRep, 6356 void *pArg, 6357 int(*xCompare)(void*,int,const void*,int,const void*), 6358 void(*xDestroy)(void*) 6359 ); 6360 SQLITE_API int sqlite3_create_collation16( 6361 sqlite3*, 6362 const void *zName, 6363 int eTextRep, 6364 void *pArg, 6365 int(*xCompare)(void*,int,const void*,int,const void*) 6366 ); 6367 6368 /* 6369 ** CAPI3REF: Collation Needed Callbacks 6370 ** METHOD: sqlite3 6371 ** 6372 ** ^To avoid having to register all collation sequences before a database 6373 ** can be used, a single callback function may be registered with the 6374 ** [database connection] to be invoked whenever an undefined collation 6375 ** sequence is required. 6376 ** 6377 ** ^If the function is registered using the sqlite3_collation_needed() API, 6378 ** then it is passed the names of undefined collation sequences as strings 6379 ** encoded in UTF-8. ^If sqlite3_collation_needed16() is used, 6380 ** the names are passed as UTF-16 in machine native byte order. 6381 ** ^A call to either function replaces the existing collation-needed callback. 6382 ** 6383 ** ^(When the callback is invoked, the first argument passed is a copy 6384 ** of the second argument to sqlite3_collation_needed() or 6385 ** sqlite3_collation_needed16(). The second argument is the database 6386 ** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE], 6387 ** or [SQLITE_UTF16LE], indicating the most desirable form of the collation 6388 ** sequence function required. The fourth parameter is the name of the 6389 ** required collation sequence.)^ 6390 ** 6391 ** The callback function should register the desired collation using 6392 ** [sqlite3_create_collation()], [sqlite3_create_collation16()], or 6393 ** [sqlite3_create_collation_v2()]. 6394 */ 6395 SQLITE_API int sqlite3_collation_needed( 6396 sqlite3*, 6397 void*, 6398 void(*)(void*,sqlite3*,int eTextRep,const char*) 6399 ); 6400 SQLITE_API int sqlite3_collation_needed16( 6401 sqlite3*, 6402 void*, 6403 void(*)(void*,sqlite3*,int eTextRep,const void*) 6404 ); 6405 6406 #ifdef SQLITE_ENABLE_CEROD 6407 /* 6408 ** Specify the activation key for a CEROD database. Unless 6409 ** activated, none of the CEROD routines will work. 6410 */ 6411 SQLITE_API void sqlite3_activate_cerod( 6412 const char *zPassPhrase /* Activation phrase */ 6413 ); 6414 #endif 6415 6416 /* 6417 ** CAPI3REF: Suspend Execution For A Short Time 6418 ** 6419 ** The sqlite3_sleep() function causes the current thread to suspend execution 6420 ** for at least a number of milliseconds specified in its parameter. 6421 ** 6422 ** If the operating system does not support sleep requests with 6423 ** millisecond time resolution, then the time will be rounded up to 6424 ** the nearest second. The number of milliseconds of sleep actually 6425 ** requested from the operating system is returned. 6426 ** 6427 ** ^SQLite implements this interface by calling the xSleep() 6428 ** method of the default [sqlite3_vfs] object. If the xSleep() method 6429 ** of the default VFS is not implemented correctly, or not implemented at 6430 ** all, then the behavior of sqlite3_sleep() may deviate from the description 6431 ** in the previous paragraphs. 6432 ** 6433 ** If a negative argument is passed to sqlite3_sleep() the results vary by 6434 ** VFS and operating system. Some system treat a negative argument as an 6435 ** instruction to sleep forever. Others understand it to mean do not sleep 6436 ** at all. ^In SQLite version 3.42.0 and later, a negative 6437 ** argument passed into sqlite3_sleep() is changed to zero before it is relayed 6438 ** down into the xSleep method of the VFS. 6439 */ 6440 SQLITE_API int sqlite3_sleep(int); 6441 6442 /* 6443 ** CAPI3REF: Name Of The Folder Holding Temporary Files 6444 ** 6445 ** ^(If this global variable is made to point to a string which is 6446 ** the name of a folder (a.k.a. directory), then all temporary files 6447 ** created by SQLite when using a built-in [sqlite3_vfs | VFS] 6448 ** will be placed in that directory.)^ ^If this variable 6449 ** is a NULL pointer, then SQLite performs a search for an appropriate 6450 ** temporary file directory. 6451 ** 6452 ** Applications are strongly discouraged from using this global variable. 6453 ** It is required to set a temporary folder on Windows Runtime (WinRT). 6454 ** But for all other platforms, it is highly recommended that applications 6455 ** neither read nor write this variable. This global variable is a relic 6456 ** that exists for backwards compatibility of legacy applications and should 6457 ** be avoided in new projects. 6458 ** 6459 ** It is not safe to read or modify this variable in more than one 6460 ** thread at a time. It is not safe to read or modify this variable 6461 ** if a [database connection] is being used at the same time in a separate 6462 ** thread. 6463 ** It is intended that this variable be set once 6464 ** as part of process initialization and before any SQLite interface 6465 ** routines have been called and that this variable remain unchanged 6466 ** thereafter. 6467 ** 6468 ** ^The [temp_store_directory pragma] may modify this variable and cause 6469 ** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore, 6470 ** the [temp_store_directory pragma] always assumes that any string 6471 ** that this variable points to is held in memory obtained from 6472 ** [sqlite3_malloc] and the pragma may attempt to free that memory 6473 ** using [sqlite3_free]. 6474 ** Hence, if this variable is modified directly, either it should be 6475 ** made NULL or made to point to memory obtained from [sqlite3_malloc] 6476 ** or else the use of the [temp_store_directory pragma] should be avoided. 6477 ** Except when requested by the [temp_store_directory pragma], SQLite 6478 ** does not free the memory that sqlite3_temp_directory points to. If 6479 ** the application wants that memory to be freed, it must do 6480 ** so itself, taking care to only do so after all [database connection] 6481 ** objects have been destroyed. 6482 ** 6483 ** <b>Note to Windows Runtime users:</b> The temporary directory must be set 6484 ** prior to calling [sqlite3_open] or [sqlite3_open_v2]. Otherwise, various 6485 ** features that require the use of temporary files may fail. Here is an 6486 ** example of how to do this using C++ with the Windows Runtime: 6487 ** 6488 ** <blockquote><pre> 6489 ** LPCWSTR zPath = Windows::Storage::ApplicationData::Current-> 6490 ** TemporaryFolder->Path->Data(); 6491 ** char zPathBuf[MAX_PATH + 1]; 6492 ** memset(zPathBuf, 0, sizeof(zPathBuf)); 6493 ** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf), 6494 ** NULL, NULL); 6495 ** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf); 6496 ** </pre></blockquote> 6497 */ 6498 SQLITE_API SQLITE_EXTERN char *sqlite3_temp_directory; 6499 6500 /* 6501 ** CAPI3REF: Name Of The Folder Holding Database Files 6502 ** 6503 ** ^(If this global variable is made to point to a string which is 6504 ** the name of a folder (a.k.a. directory), then all database files 6505 ** specified with a relative pathname and created or accessed by 6506 ** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed 6507 ** to be relative to that directory.)^ ^If this variable is a NULL 6508 ** pointer, then SQLite assumes that all database files specified 6509 ** with a relative pathname are relative to the current directory 6510 ** for the process. Only the windows VFS makes use of this global 6511 ** variable; it is ignored by the unix VFS. 6512 ** 6513 ** Changing the value of this variable while a database connection is 6514 ** open can result in a corrupt database. 6515 ** 6516 ** It is not safe to read or modify this variable in more than one 6517 ** thread at a time. It is not safe to read or modify this variable 6518 ** if a [database connection] is being used at the same time in a separate 6519 ** thread. 6520 ** It is intended that this variable be set once 6521 ** as part of process initialization and before any SQLite interface 6522 ** routines have been called and that this variable remain unchanged 6523 ** thereafter. 6524 ** 6525 ** ^The [data_store_directory pragma] may modify this variable and cause 6526 ** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore, 6527 ** the [data_store_directory pragma] always assumes that any string 6528 ** that this variable points to is held in memory obtained from 6529 ** [sqlite3_malloc] and the pragma may attempt to free that memory 6530 ** using [sqlite3_free]. 6531 ** Hence, if this variable is modified directly, either it should be 6532 ** made NULL or made to point to memory obtained from [sqlite3_malloc] 6533 ** or else the use of the [data_store_directory pragma] should be avoided. 6534 */ 6535 SQLITE_API SQLITE_EXTERN char *sqlite3_data_directory; 6536 6537 /* 6538 ** CAPI3REF: Win32 Specific Interface 6539 ** 6540 ** These interfaces are available only on Windows. The 6541 ** [sqlite3_win32_set_directory] interface is used to set the value associated 6542 ** with the [sqlite3_temp_directory] or [sqlite3_data_directory] variable, to 6543 ** zValue, depending on the value of the type parameter. The zValue parameter 6544 ** should be NULL to cause the previous value to be freed via [sqlite3_free]; 6545 ** a non-NULL value will be copied into memory obtained from [sqlite3_malloc] 6546 ** prior to being used. The [sqlite3_win32_set_directory] interface returns 6547 ** [SQLITE_OK] to indicate success, [SQLITE_ERROR] if the type is unsupported, 6548 ** or [SQLITE_NOMEM] if memory could not be allocated. The value of the 6549 ** [sqlite3_data_directory] variable is intended to act as a replacement for 6550 ** the current directory on the sub-platforms of Win32 where that concept is 6551 ** not present, e.g. WinRT and UWP. The [sqlite3_win32_set_directory8] and 6552 ** [sqlite3_win32_set_directory16] interfaces behave exactly the same as the 6553 ** sqlite3_win32_set_directory interface except the string parameter must be 6554 ** UTF-8 or UTF-16, respectively. 6555 */ 6556 SQLITE_API int sqlite3_win32_set_directory( 6557 unsigned long type, /* Identifier for directory being set or reset */ 6558 void *zValue /* New value for directory being set or reset */ 6559 ); 6560 SQLITE_API int sqlite3_win32_set_directory8(unsigned long type, const char *zValue); 6561 SQLITE_API int sqlite3_win32_set_directory16(unsigned long type, const void *zValue); 6562 6563 /* 6564 ** CAPI3REF: Win32 Directory Types 6565 ** 6566 ** These macros are only available on Windows. They define the allowed values 6567 ** for the type argument to the [sqlite3_win32_set_directory] interface. 6568 */ 6569 #define SQLITE_WIN32_DATA_DIRECTORY_TYPE 1 6570 #define SQLITE_WIN32_TEMP_DIRECTORY_TYPE 2 6571 6572 /* 6573 ** CAPI3REF: Test For Auto-Commit Mode 6574 ** KEYWORDS: {autocommit mode} 6575 ** METHOD: sqlite3 6576 ** 6577 ** ^The sqlite3_get_autocommit() interface returns non-zero or 6578 ** zero if the given database connection is or is not in autocommit mode, 6579 ** respectively. ^Autocommit mode is on by default. 6580 ** ^Autocommit mode is disabled by a [BEGIN] statement. 6581 ** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK]. 6582 ** 6583 ** If certain kinds of errors occur on a statement within a multi-statement 6584 ** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR], 6585 ** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the 6586 ** transaction might be rolled back automatically. The only way to 6587 ** find out whether SQLite automatically rolled back the transaction after 6588 ** an error is to use this function. 6589 ** 6590 ** If another thread changes the autocommit status of the database 6591 ** connection while this routine is running, then the return value 6592 ** is undefined. 6593 */ 6594 SQLITE_API int sqlite3_get_autocommit(sqlite3*); 6595 6596 /* 6597 ** CAPI3REF: Find The Database Handle Of A Prepared Statement 6598 ** METHOD: sqlite3_stmt 6599 ** 6600 ** ^The sqlite3_db_handle interface returns the [database connection] handle 6601 ** to which a [prepared statement] belongs. ^The [database connection] 6602 ** returned by sqlite3_db_handle is the same [database connection] 6603 ** that was the first argument 6604 ** to the [sqlite3_prepare_v2()] call (or its variants) that was used to 6605 ** create the statement in the first place. 6606 */ 6607 SQLITE_API sqlite3 *sqlite3_db_handle(sqlite3_stmt*); 6608 6609 /* 6610 ** CAPI3REF: Return The Schema Name For A Database Connection 6611 ** METHOD: sqlite3 6612 ** 6613 ** ^The sqlite3_db_name(D,N) interface returns a pointer to the schema name 6614 ** for the N-th database on database connection D, or a NULL pointer of N is 6615 ** out of range. An N value of 0 means the main database file. An N of 1 is 6616 ** the "temp" schema. Larger values of N correspond to various ATTACH-ed 6617 ** databases. 6618 ** 6619 ** Space to hold the string that is returned by sqlite3_db_name() is managed 6620 ** by SQLite itself. The string might be deallocated by any operation that 6621 ** changes the schema, including [ATTACH] or [DETACH] or calls to 6622 ** [sqlite3_serialize()] or [sqlite3_deserialize()], even operations that 6623 ** occur on a different thread. Applications that need to 6624 ** remember the string long-term should make their own copy. Applications that 6625 ** are accessing the same database connection simultaneously on multiple 6626 ** threads should mutex-protect calls to this API and should make their own 6627 ** private copy of the result prior to releasing the mutex. 6628 */ 6629 SQLITE_API const char *sqlite3_db_name(sqlite3 *db, int N); 6630 6631 /* 6632 ** CAPI3REF: Return The Filename For A Database Connection 6633 ** METHOD: sqlite3 6634 ** 6635 ** ^The sqlite3_db_filename(D,N) interface returns a pointer to the filename 6636 ** associated with database N of connection D. 6637 ** ^If there is no attached database N on the database 6638 ** connection D, or if database N is a temporary or in-memory database, then 6639 ** this function will return either a NULL pointer or an empty string. 6640 ** 6641 ** ^The string value returned by this routine is owned and managed by 6642 ** the database connection. ^The value will be valid until the database N 6643 ** is [DETACH]-ed or until the database connection closes. 6644 ** 6645 ** ^The filename returned by this function is the output of the 6646 ** xFullPathname method of the [VFS]. ^In other words, the filename 6647 ** will be an absolute pathname, even if the filename used 6648 ** to open the database originally was a URI or relative pathname. 6649 ** 6650 ** If the filename pointer returned by this routine is not NULL, then it 6651 ** can be used as the filename input parameter to these routines: 6652 ** <ul> 6653 ** <li> [sqlite3_uri_parameter()] 6654 ** <li> [sqlite3_uri_boolean()] 6655 ** <li> [sqlite3_uri_int64()] 6656 ** <li> [sqlite3_filename_database()] 6657 ** <li> [sqlite3_filename_journal()] 6658 ** <li> [sqlite3_filename_wal()] 6659 ** </ul> 6660 */ 6661 SQLITE_API sqlite3_filename sqlite3_db_filename(sqlite3 *db, const char *zDbName); 6662 6663 /* 6664 ** CAPI3REF: Determine if a database is read-only 6665 ** METHOD: sqlite3 6666 ** 6667 ** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N 6668 ** of connection D is read-only, 0 if it is read/write, or -1 if N is not 6669 ** the name of a database on connection D. 6670 */ 6671 SQLITE_API int sqlite3_db_readonly(sqlite3 *db, const char *zDbName); 6672 6673 /* 6674 ** CAPI3REF: Determine the transaction state of a database 6675 ** METHOD: sqlite3 6676 ** 6677 ** ^The sqlite3_txn_state(D,S) interface returns the current 6678 ** [transaction state] of schema S in database connection D. ^If S is NULL, 6679 ** then the highest transaction state of any schema on database connection D 6680 ** is returned. Transaction states are (in order of lowest to highest): 6681 ** <ol> 6682 ** <li value="0"> SQLITE_TXN_NONE 6683 ** <li value="1"> SQLITE_TXN_READ 6684 ** <li value="2"> SQLITE_TXN_WRITE 6685 ** </ol> 6686 ** ^If the S argument to sqlite3_txn_state(D,S) is not the name of 6687 ** a valid schema, then -1 is returned. 6688 */ 6689 SQLITE_API int sqlite3_txn_state(sqlite3*,const char *zSchema); 6690 6691 /* 6692 ** CAPI3REF: Allowed return values from sqlite3_txn_state() 6693 ** KEYWORDS: {transaction state} 6694 ** 6695 ** These constants define the current transaction state of a database file. 6696 ** ^The [sqlite3_txn_state(D,S)] interface returns one of these 6697 ** constants in order to describe the transaction state of schema S 6698 ** in [database connection] D. 6699 ** 6700 ** <dl> 6701 ** [[SQLITE_TXN_NONE]] <dt>SQLITE_TXN_NONE</dt> 6702 ** <dd>The SQLITE_TXN_NONE state means that no transaction is currently 6703 ** pending.</dd> 6704 ** 6705 ** [[SQLITE_TXN_READ]] <dt>SQLITE_TXN_READ</dt> 6706 ** <dd>The SQLITE_TXN_READ state means that the database is currently 6707 ** in a read transaction. Content has been read from the database file 6708 ** but nothing in the database file has changed. The transaction state 6709 ** will advanced to SQLITE_TXN_WRITE if any changes occur and there are 6710 ** no other conflicting concurrent write transactions. The transaction 6711 ** state will revert to SQLITE_TXN_NONE following a [ROLLBACK] or 6712 ** [COMMIT].</dd> 6713 ** 6714 ** [[SQLITE_TXN_WRITE]] <dt>SQLITE_TXN_WRITE</dt> 6715 ** <dd>The SQLITE_TXN_WRITE state means that the database is currently 6716 ** in a write transaction. Content has been written to the database file 6717 ** but has not yet committed. The transaction state will change to 6718 ** to SQLITE_TXN_NONE at the next [ROLLBACK] or [COMMIT].</dd> 6719 */ 6720 #define SQLITE_TXN_NONE 0 6721 #define SQLITE_TXN_READ 1 6722 #define SQLITE_TXN_WRITE 2 6723 6724 /* 6725 ** CAPI3REF: Find the next prepared statement 6726 ** METHOD: sqlite3 6727 ** 6728 ** ^This interface returns a pointer to the next [prepared statement] after 6729 ** pStmt associated with the [database connection] pDb. ^If pStmt is NULL 6730 ** then this interface returns a pointer to the first prepared statement 6731 ** associated with the database connection pDb. ^If no prepared statement 6732 ** satisfies the conditions of this routine, it returns NULL. 6733 ** 6734 ** The [database connection] pointer D in a call to 6735 ** [sqlite3_next_stmt(D,S)] must refer to an open database 6736 ** connection and in particular must not be a NULL pointer. 6737 */ 6738 SQLITE_API sqlite3_stmt *sqlite3_next_stmt(sqlite3 *pDb, sqlite3_stmt *pStmt); 6739 6740 /* 6741 ** CAPI3REF: Commit And Rollback Notification Callbacks 6742 ** METHOD: sqlite3 6743 ** 6744 ** ^The sqlite3_commit_hook() interface registers a callback 6745 ** function to be invoked whenever a transaction is [COMMIT | committed]. 6746 ** ^Any callback set by a previous call to sqlite3_commit_hook() 6747 ** for the same database connection is overridden. 6748 ** ^The sqlite3_rollback_hook() interface registers a callback 6749 ** function to be invoked whenever a transaction is [ROLLBACK | rolled back]. 6750 ** ^Any callback set by a previous call to sqlite3_rollback_hook() 6751 ** for the same database connection is overridden. 6752 ** ^The pArg argument is passed through to the callback. 6753 ** ^If the callback on a commit hook function returns non-zero, 6754 ** then the commit is converted into a rollback. 6755 ** 6756 ** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions 6757 ** return the P argument from the previous call of the same function 6758 ** on the same [database connection] D, or NULL for 6759 ** the first call for each function on D. 6760 ** 6761 ** The commit and rollback hook callbacks are not reentrant. 6762 ** The callback implementation must not do anything that will modify 6763 ** the database connection that invoked the callback. Any actions 6764 ** to modify the database connection must be deferred until after the 6765 ** completion of the [sqlite3_step()] call that triggered the commit 6766 ** or rollback hook in the first place. 6767 ** Note that running any other SQL statements, including SELECT statements, 6768 ** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify 6769 ** the database connections for the meaning of "modify" in this paragraph. 6770 ** 6771 ** ^Registering a NULL function disables the callback. 6772 ** 6773 ** ^When the commit hook callback routine returns zero, the [COMMIT] 6774 ** operation is allowed to continue normally. ^If the commit hook 6775 ** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK]. 6776 ** ^The rollback hook is invoked on a rollback that results from a commit 6777 ** hook returning non-zero, just as it would be with any other rollback. 6778 ** 6779 ** ^For the purposes of this API, a transaction is said to have been 6780 ** rolled back if an explicit "ROLLBACK" statement is executed, or 6781 ** an error or constraint causes an implicit rollback to occur. 6782 ** ^The rollback callback is not invoked if a transaction is 6783 ** automatically rolled back because the database connection is closed. 6784 ** 6785 ** See also the [sqlite3_update_hook()] interface. 6786 */ 6787 SQLITE_API void *sqlite3_commit_hook(sqlite3*, int(*)(void*), void*); 6788 SQLITE_API void *sqlite3_rollback_hook(sqlite3*, void(*)(void *), void*); 6789 6790 /* 6791 ** CAPI3REF: Autovacuum Compaction Amount Callback 6792 ** METHOD: sqlite3 6793 ** 6794 ** ^The sqlite3_autovacuum_pages(D,C,P,X) interface registers a callback 6795 ** function C that is invoked prior to each autovacuum of the database 6796 ** file. ^The callback is passed a copy of the generic data pointer (P), 6797 ** the schema-name of the attached database that is being autovacuumed, 6798 ** the size of the database file in pages, the number of free pages, 6799 ** and the number of bytes per page, respectively. The callback should 6800 ** return the number of free pages that should be removed by the 6801 ** autovacuum. ^If the callback returns zero, then no autovacuum happens. 6802 ** ^If the value returned is greater than or equal to the number of 6803 ** free pages, then a complete autovacuum happens. 6804 ** 6805 ** <p>^If there are multiple ATTACH-ed database files that are being 6806 ** modified as part of a transaction commit, then the autovacuum pages 6807 ** callback is invoked separately for each file. 6808 ** 6809 ** <p><b>The callback is not reentrant.</b> The callback function should 6810 ** not attempt to invoke any other SQLite interface. If it does, bad 6811 ** things may happen, including segmentation faults and corrupt database 6812 ** files. The callback function should be a simple function that 6813 ** does some arithmetic on its input parameters and returns a result. 6814 ** 6815 ** ^The X parameter to sqlite3_autovacuum_pages(D,C,P,X) is an optional 6816 ** destructor for the P parameter. ^If X is not NULL, then X(P) is 6817 ** invoked whenever the database connection closes or when the callback 6818 ** is overwritten by another invocation of sqlite3_autovacuum_pages(). 6819 ** 6820 ** <p>^There is only one autovacuum pages callback per database connection. 6821 ** ^Each call to the sqlite3_autovacuum_pages() interface overrides all 6822 ** previous invocations for that database connection. ^If the callback 6823 ** argument (C) to sqlite3_autovacuum_pages(D,C,P,X) is a NULL pointer, 6824 ** then the autovacuum steps callback is canceled. The return value 6825 ** from sqlite3_autovacuum_pages() is normally SQLITE_OK, but might 6826 ** be some other error code if something goes wrong. The current 6827 ** implementation will only return SQLITE_OK or SQLITE_MISUSE, but other 6828 ** return codes might be added in future releases. 6829 ** 6830 ** <p>If no autovacuum pages callback is specified (the usual case) or 6831 ** a NULL pointer is provided for the callback, 6832 ** then the default behavior is to vacuum all free pages. So, in other 6833 ** words, the default behavior is the same as if the callback function 6834 ** were something like this: 6835 ** 6836 ** <blockquote><pre> 6837 ** unsigned int demonstration_autovac_pages_callback( 6838 ** void *pClientData, 6839 ** const char *zSchema, 6840 ** unsigned int nDbPage, 6841 ** unsigned int nFreePage, 6842 ** unsigned int nBytePerPage 6843 ** ){ 6844 ** return nFreePage; 6845 ** } 6846 ** </pre></blockquote> 6847 */ 6848 SQLITE_API int sqlite3_autovacuum_pages( 6849 sqlite3 *db, 6850 unsigned int(*)(void*,const char*,unsigned int,unsigned int,unsigned int), 6851 void*, 6852 void(*)(void*) 6853 ); 6854 6855 6856 /* 6857 ** CAPI3REF: Data Change Notification Callbacks 6858 ** METHOD: sqlite3 6859 ** 6860 ** ^The sqlite3_update_hook() interface registers a callback function 6861 ** with the [database connection] identified by the first argument 6862 ** to be invoked whenever a row is updated, inserted or deleted in 6863 ** a [rowid table]. 6864 ** ^Any callback set by a previous call to this function 6865 ** for the same database connection is overridden. 6866 ** 6867 ** ^The second argument is a pointer to the function to invoke when a 6868 ** row is updated, inserted or deleted in a rowid table. 6869 ** ^The first argument to the callback is a copy of the third argument 6870 ** to sqlite3_update_hook(). 6871 ** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE], 6872 ** or [SQLITE_UPDATE], depending on the operation that caused the callback 6873 ** to be invoked. 6874 ** ^The third and fourth arguments to the callback contain pointers to the 6875 ** database and table name containing the affected row. 6876 ** ^The final callback parameter is the [rowid] of the row. 6877 ** ^In the case of an update, this is the [rowid] after the update takes place. 6878 ** 6879 ** ^(The update hook is not invoked when internal system tables are 6880 ** modified (i.e. sqlite_sequence).)^ 6881 ** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified. 6882 ** 6883 ** ^In the current implementation, the update hook 6884 ** is not invoked when conflicting rows are deleted because of an 6885 ** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook 6886 ** invoked when rows are deleted using the [truncate optimization]. 6887 ** The exceptions defined in this paragraph might change in a future 6888 ** release of SQLite. 6889 ** 6890 ** Whether the update hook is invoked before or after the 6891 ** corresponding change is currently unspecified and may differ 6892 ** depending on the type of change. Do not rely on the order of the 6893 ** hook call with regards to the final result of the operation which 6894 ** triggers the hook. 6895 ** 6896 ** The update hook implementation must not do anything that will modify 6897 ** the database connection that invoked the update hook. Any actions 6898 ** to modify the database connection must be deferred until after the 6899 ** completion of the [sqlite3_step()] call that triggered the update hook. 6900 ** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their 6901 ** database connections for the meaning of "modify" in this paragraph. 6902 ** 6903 ** ^The sqlite3_update_hook(D,C,P) function 6904 ** returns the P argument from the previous call 6905 ** on the same [database connection] D, or NULL for 6906 ** the first call on D. 6907 ** 6908 ** See also the [sqlite3_commit_hook()], [sqlite3_rollback_hook()], 6909 ** and [sqlite3_preupdate_hook()] interfaces. 6910 */ 6911 SQLITE_API void *sqlite3_update_hook( 6912 sqlite3*, 6913 void(*)(void *,int ,char const *,char const *,sqlite3_int64), 6914 void* 6915 ); 6916 6917 /* 6918 ** CAPI3REF: Enable Or Disable Shared Pager Cache 6919 ** 6920 ** ^(This routine enables or disables the sharing of the database cache 6921 ** and schema data structures between [database connection | connections] 6922 ** to the same database. Sharing is enabled if the argument is true 6923 ** and disabled if the argument is false.)^ 6924 ** 6925 ** This interface is omitted if SQLite is compiled with 6926 ** [-DSQLITE_OMIT_SHARED_CACHE]. The [-DSQLITE_OMIT_SHARED_CACHE] 6927 ** compile-time option is recommended because the 6928 ** [use of shared cache mode is discouraged]. 6929 ** 6930 ** ^Cache sharing is enabled and disabled for an entire process. 6931 ** This is a change as of SQLite [version 3.5.0] ([dateof:3.5.0]). 6932 ** In prior versions of SQLite, 6933 ** sharing was enabled or disabled for each thread separately. 6934 ** 6935 ** ^(The cache sharing mode set by this interface effects all subsequent 6936 ** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()]. 6937 ** Existing database connections continue to use the sharing mode 6938 ** that was in effect at the time they were opened.)^ 6939 ** 6940 ** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled 6941 ** successfully. An [error code] is returned otherwise.)^ 6942 ** 6943 ** ^Shared cache is disabled by default. It is recommended that it stay 6944 ** that way. In other words, do not use this routine. This interface 6945 ** continues to be provided for historical compatibility, but its use is 6946 ** discouraged. Any use of shared cache is discouraged. If shared cache 6947 ** must be used, it is recommended that shared cache only be enabled for 6948 ** individual database connections using the [sqlite3_open_v2()] interface 6949 ** with the [SQLITE_OPEN_SHAREDCACHE] flag. 6950 ** 6951 ** Note: This method is disabled on MacOS X 10.7 and iOS version 5.0 6952 ** and will always return SQLITE_MISUSE. On those systems, 6953 ** shared cache mode should be enabled per-database connection via 6954 ** [sqlite3_open_v2()] with [SQLITE_OPEN_SHAREDCACHE]. 6955 ** 6956 ** This interface is threadsafe on processors where writing a 6957 ** 32-bit integer is atomic. 6958 ** 6959 ** See Also: [SQLite Shared-Cache Mode] 6960 */ 6961 SQLITE_API int sqlite3_enable_shared_cache(int); 6962 6963 /* 6964 ** CAPI3REF: Attempt To Free Heap Memory 6965 ** 6966 ** ^The sqlite3_release_memory() interface attempts to free N bytes 6967 ** of heap memory by deallocating non-essential memory allocations 6968 ** held by the database library. Memory used to cache database 6969 ** pages to improve performance is an example of non-essential memory. 6970 ** ^sqlite3_release_memory() returns the number of bytes actually freed, 6971 ** which might be more or less than the amount requested. 6972 ** ^The sqlite3_release_memory() routine is a no-op returning zero 6973 ** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT]. 6974 ** 6975 ** See also: [sqlite3_db_release_memory()] 6976 */ 6977 SQLITE_API int sqlite3_release_memory(int); 6978 6979 /* 6980 ** CAPI3REF: Free Memory Used By A Database Connection 6981 ** METHOD: sqlite3 6982 ** 6983 ** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap 6984 ** memory as possible from database connection D. Unlike the 6985 ** [sqlite3_release_memory()] interface, this interface is in effect even 6986 ** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is 6987 ** omitted. 6988 ** 6989 ** See also: [sqlite3_release_memory()] 6990 */ 6991 SQLITE_API int sqlite3_db_release_memory(sqlite3*); 6992 6993 /* 6994 ** CAPI3REF: Impose A Limit On Heap Size 6995 ** 6996 ** These interfaces impose limits on the amount of heap memory that will be 6997 ** by all database connections within a single process. 6998 ** 6999 ** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the 7000 ** soft limit on the amount of heap memory that may be allocated by SQLite. 7001 ** ^SQLite strives to keep heap memory utilization below the soft heap 7002 ** limit by reducing the number of pages held in the page cache 7003 ** as heap memory usages approaches the limit. 7004 ** ^The soft heap limit is "soft" because even though SQLite strives to stay 7005 ** below the limit, it will exceed the limit rather than generate 7006 ** an [SQLITE_NOMEM] error. In other words, the soft heap limit 7007 ** is advisory only. 7008 ** 7009 ** ^The sqlite3_hard_heap_limit64(N) interface sets a hard upper bound of 7010 ** N bytes on the amount of memory that will be allocated. ^The 7011 ** sqlite3_hard_heap_limit64(N) interface is similar to 7012 ** sqlite3_soft_heap_limit64(N) except that memory allocations will fail 7013 ** when the hard heap limit is reached. 7014 ** 7015 ** ^The return value from both sqlite3_soft_heap_limit64() and 7016 ** sqlite3_hard_heap_limit64() is the size of 7017 ** the heap limit prior to the call, or negative in the case of an 7018 ** error. ^If the argument N is negative 7019 ** then no change is made to the heap limit. Hence, the current 7020 ** size of heap limits can be determined by invoking 7021 ** sqlite3_soft_heap_limit64(-1) or sqlite3_hard_heap_limit(-1). 7022 ** 7023 ** ^Setting the heap limits to zero disables the heap limiter mechanism. 7024 ** 7025 ** ^The soft heap limit may not be greater than the hard heap limit. 7026 ** ^If the hard heap limit is enabled and if sqlite3_soft_heap_limit(N) 7027 ** is invoked with a value of N that is greater than the hard heap limit, 7028 ** the soft heap limit is set to the value of the hard heap limit. 7029 ** ^The soft heap limit is automatically enabled whenever the hard heap 7030 ** limit is enabled. ^When sqlite3_hard_heap_limit64(N) is invoked and 7031 ** the soft heap limit is outside the range of 1..N, then the soft heap 7032 ** limit is set to N. ^Invoking sqlite3_soft_heap_limit64(0) when the 7033 ** hard heap limit is enabled makes the soft heap limit equal to the 7034 ** hard heap limit. 7035 ** 7036 ** The memory allocation limits can also be adjusted using 7037 ** [PRAGMA soft_heap_limit] and [PRAGMA hard_heap_limit]. 7038 ** 7039 ** ^(The heap limits are not enforced in the current implementation 7040 ** if one or more of following conditions are true: 7041 ** 7042 ** <ul> 7043 ** <li> The limit value is set to zero. 7044 ** <li> Memory accounting is disabled using a combination of the 7045 ** [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and 7046 ** the [SQLITE_DEFAULT_MEMSTATUS] compile-time option. 7047 ** <li> An alternative page cache implementation is specified using 7048 ** [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...). 7049 ** <li> The page cache allocates from its own memory pool supplied 7050 ** by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than 7051 ** from the heap. 7052 ** </ul>)^ 7053 ** 7054 ** The circumstances under which SQLite will enforce the heap limits may 7055 ** changes in future releases of SQLite. 7056 */ 7057 SQLITE_API sqlite3_int64 sqlite3_soft_heap_limit64(sqlite3_int64 N); 7058 SQLITE_API sqlite3_int64 sqlite3_hard_heap_limit64(sqlite3_int64 N); 7059 7060 /* 7061 ** CAPI3REF: Deprecated Soft Heap Limit Interface 7062 ** DEPRECATED 7063 ** 7064 ** This is a deprecated version of the [sqlite3_soft_heap_limit64()] 7065 ** interface. This routine is provided for historical compatibility 7066 ** only. All new applications should use the 7067 ** [sqlite3_soft_heap_limit64()] interface rather than this one. 7068 */ 7069 SQLITE_API SQLITE_DEPRECATED void sqlite3_soft_heap_limit(int N); 7070 7071 7072 /* 7073 ** CAPI3REF: Extract Metadata About A Column Of A Table 7074 ** METHOD: sqlite3 7075 ** 7076 ** ^(The sqlite3_table_column_metadata(X,D,T,C,....) routine returns 7077 ** information about column C of table T in database D 7078 ** on [database connection] X.)^ ^The sqlite3_table_column_metadata() 7079 ** interface returns SQLITE_OK and fills in the non-NULL pointers in 7080 ** the final five arguments with appropriate values if the specified 7081 ** column exists. ^The sqlite3_table_column_metadata() interface returns 7082 ** SQLITE_ERROR if the specified column does not exist. 7083 ** ^If the column-name parameter to sqlite3_table_column_metadata() is a 7084 ** NULL pointer, then this routine simply checks for the existence of the 7085 ** table and returns SQLITE_OK if the table exists and SQLITE_ERROR if it 7086 ** does not. If the table name parameter T in a call to 7087 ** sqlite3_table_column_metadata(X,D,T,C,...) is NULL then the result is 7088 ** undefined behavior. 7089 ** 7090 ** ^The column is identified by the second, third and fourth parameters to 7091 ** this function. ^(The second parameter is either the name of the database 7092 ** (i.e. "main", "temp", or an attached database) containing the specified 7093 ** table or NULL.)^ ^If it is NULL, then all attached databases are searched 7094 ** for the table using the same algorithm used by the database engine to 7095 ** resolve unqualified table references. 7096 ** 7097 ** ^The third and fourth parameters to this function are the table and column 7098 ** name of the desired column, respectively. 7099 ** 7100 ** ^Metadata is returned by writing to the memory locations passed as the 5th 7101 ** and subsequent parameters to this function. ^Any of these arguments may be 7102 ** NULL, in which case the corresponding element of metadata is omitted. 7103 ** 7104 ** ^(<blockquote> 7105 ** <table border="1"> 7106 ** <tr><th> Parameter <th> Output<br>Type <th> Description 7107 ** 7108 ** <tr><td> 5th <td> const char* <td> Data type 7109 ** <tr><td> 6th <td> const char* <td> Name of default collation sequence 7110 ** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint 7111 ** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY 7112 ** <tr><td> 9th <td> int <td> True if column is [AUTOINCREMENT] 7113 ** </table> 7114 ** </blockquote>)^ 7115 ** 7116 ** ^The memory pointed to by the character pointers returned for the 7117 ** declaration type and collation sequence is valid until the next 7118 ** call to any SQLite API function. 7119 ** 7120 ** ^If the specified table is actually a view, an [error code] is returned. 7121 ** 7122 ** ^If the specified column is "rowid", "oid" or "_rowid_" and the table 7123 ** is not a [WITHOUT ROWID] table and an 7124 ** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output 7125 ** parameters are set for the explicitly declared column. ^(If there is no 7126 ** [INTEGER PRIMARY KEY] column, then the outputs 7127 ** for the [rowid] are set as follows: 7128 ** 7129 ** <pre> 7130 ** data type: "INTEGER" 7131 ** collation sequence: "BINARY" 7132 ** not null: 0 7133 ** primary key: 1 7134 ** auto increment: 0 7135 ** </pre>)^ 7136 ** 7137 ** ^This function causes all database schemas to be read from disk and 7138 ** parsed, if that has not already been done, and returns an error if 7139 ** any errors are encountered while loading the schema. 7140 */ 7141 SQLITE_API int sqlite3_table_column_metadata( 7142 sqlite3 *db, /* Connection handle */ 7143 const char *zDbName, /* Database name or NULL */ 7144 const char *zTableName, /* Table name */ 7145 const char *zColumnName, /* Column name */ 7146 char const **pzDataType, /* OUTPUT: Declared data type */ 7147 char const **pzCollSeq, /* OUTPUT: Collation sequence name */ 7148 int *pNotNull, /* OUTPUT: True if NOT NULL constraint exists */ 7149 int *pPrimaryKey, /* OUTPUT: True if column part of PK */ 7150 int *pAutoinc /* OUTPUT: True if column is auto-increment */ 7151 ); 7152 7153 /* 7154 ** CAPI3REF: Load An Extension 7155 ** METHOD: sqlite3 7156 ** 7157 ** ^This interface loads an SQLite extension library from the named file. 7158 ** 7159 ** ^The sqlite3_load_extension() interface attempts to load an 7160 ** [SQLite extension] library contained in the file zFile. If 7161 ** the file cannot be loaded directly, attempts are made to load 7162 ** with various operating-system specific extensions added. 7163 ** So for example, if "samplelib" cannot be loaded, then names like 7164 ** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might 7165 ** be tried also. 7166 ** 7167 ** ^The entry point is zProc. 7168 ** ^(zProc may be 0, in which case SQLite will try to come up with an 7169 ** entry point name on its own. It first tries "sqlite3_extension_init". 7170 ** If that does not work, it constructs a name "sqlite3_X_init" where the 7171 ** X is consists of the lower-case equivalent of all ASCII alphabetic 7172 ** characters in the filename from the last "/" to the first following 7173 ** "." and omitting any initial "lib".)^ 7174 ** ^The sqlite3_load_extension() interface returns 7175 ** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong. 7176 ** ^If an error occurs and pzErrMsg is not 0, then the 7177 ** [sqlite3_load_extension()] interface shall attempt to 7178 ** fill *pzErrMsg with error message text stored in memory 7179 ** obtained from [sqlite3_malloc()]. The calling function 7180 ** should free this memory by calling [sqlite3_free()]. 7181 ** 7182 ** ^Extension loading must be enabled using 7183 ** [sqlite3_enable_load_extension()] or 7184 ** [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],1,NULL) 7185 ** prior to calling this API, 7186 ** otherwise an error will be returned. 7187 ** 7188 ** <b>Security warning:</b> It is recommended that the 7189 ** [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method be used to enable only this 7190 ** interface. The use of the [sqlite3_enable_load_extension()] interface 7191 ** should be avoided. This will keep the SQL function [load_extension()] 7192 ** disabled and prevent SQL injections from giving attackers 7193 ** access to extension loading capabilities. 7194 ** 7195 ** See also the [load_extension() SQL function]. 7196 */ 7197 SQLITE_API int sqlite3_load_extension( 7198 sqlite3 *db, /* Load the extension into this database connection */ 7199 const char *zFile, /* Name of the shared library containing extension */ 7200 const char *zProc, /* Entry point. Derived from zFile if 0 */ 7201 char **pzErrMsg /* Put error message here if not 0 */ 7202 ); 7203 7204 /* 7205 ** CAPI3REF: Enable Or Disable Extension Loading 7206 ** METHOD: sqlite3 7207 ** 7208 ** ^So as not to open security holes in older applications that are 7209 ** unprepared to deal with [extension loading], and as a means of disabling 7210 ** [extension loading] while evaluating user-entered SQL, the following API 7211 ** is provided to turn the [sqlite3_load_extension()] mechanism on and off. 7212 ** 7213 ** ^Extension loading is off by default. 7214 ** ^Call the sqlite3_enable_load_extension() routine with onoff==1 7215 ** to turn extension loading on and call it with onoff==0 to turn 7216 ** it back off again. 7217 ** 7218 ** ^This interface enables or disables both the C-API 7219 ** [sqlite3_load_extension()] and the SQL function [load_extension()]. 7220 ** ^(Use [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],..) 7221 ** to enable or disable only the C-API.)^ 7222 ** 7223 ** <b>Security warning:</b> It is recommended that extension loading 7224 ** be enabled using the [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method 7225 ** rather than this interface, so the [load_extension()] SQL function 7226 ** remains disabled. This will prevent SQL injections from giving attackers 7227 ** access to extension loading capabilities. 7228 */ 7229 SQLITE_API int sqlite3_enable_load_extension(sqlite3 *db, int onoff); 7230 7231 /* 7232 ** CAPI3REF: Automatically Load Statically Linked Extensions 7233 ** 7234 ** ^This interface causes the xEntryPoint() function to be invoked for 7235 ** each new [database connection] that is created. The idea here is that 7236 ** xEntryPoint() is the entry point for a statically linked [SQLite extension] 7237 ** that is to be automatically loaded into all new database connections. 7238 ** 7239 ** ^(Even though the function prototype shows that xEntryPoint() takes 7240 ** no arguments and returns void, SQLite invokes xEntryPoint() with three 7241 ** arguments and expects an integer result as if the signature of the 7242 ** entry point where as follows: 7243 ** 7244 ** <blockquote><pre> 7245 ** int xEntryPoint( 7246 ** sqlite3 *db, 7247 ** const char **pzErrMsg, 7248 ** const struct sqlite3_api_routines *pThunk 7249 ** ); 7250 ** </pre></blockquote>)^ 7251 ** 7252 ** If the xEntryPoint routine encounters an error, it should make *pzErrMsg 7253 ** point to an appropriate error message (obtained from [sqlite3_mprintf()]) 7254 ** and return an appropriate [error code]. ^SQLite ensures that *pzErrMsg 7255 ** is NULL before calling the xEntryPoint(). ^SQLite will invoke 7256 ** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns. ^If any 7257 ** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()], 7258 ** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail. 7259 ** 7260 ** ^Calling sqlite3_auto_extension(X) with an entry point X that is already 7261 ** on the list of automatic extensions is a harmless no-op. ^No entry point 7262 ** will be called more than once for each database connection that is opened. 7263 ** 7264 ** See also: [sqlite3_reset_auto_extension()] 7265 ** and [sqlite3_cancel_auto_extension()] 7266 */ 7267 SQLITE_API int sqlite3_auto_extension(void(*xEntryPoint)(void)); 7268 7269 /* 7270 ** CAPI3REF: Cancel Automatic Extension Loading 7271 ** 7272 ** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the 7273 ** initialization routine X that was registered using a prior call to 7274 ** [sqlite3_auto_extension(X)]. ^The [sqlite3_cancel_auto_extension(X)] 7275 ** routine returns 1 if initialization routine X was successfully 7276 ** unregistered and it returns 0 if X was not on the list of initialization 7277 ** routines. 7278 */ 7279 SQLITE_API int sqlite3_cancel_auto_extension(void(*xEntryPoint)(void)); 7280 7281 /* 7282 ** CAPI3REF: Reset Automatic Extension Loading 7283 ** 7284 ** ^This interface disables all automatic extensions previously 7285 ** registered using [sqlite3_auto_extension()]. 7286 */ 7287 SQLITE_API void sqlite3_reset_auto_extension(void); 7288 7289 /* 7290 ** Structures used by the virtual table interface 7291 */ 7292 typedef struct sqlite3_vtab sqlite3_vtab; 7293 typedef struct sqlite3_index_info sqlite3_index_info; 7294 typedef struct sqlite3_vtab_cursor sqlite3_vtab_cursor; 7295 typedef struct sqlite3_module sqlite3_module; 7296 7297 /* 7298 ** CAPI3REF: Virtual Table Object 7299 ** KEYWORDS: sqlite3_module {virtual table module} 7300 ** 7301 ** This structure, sometimes called a "virtual table module", 7302 ** defines the implementation of a [virtual table]. 7303 ** This structure consists mostly of methods for the module. 7304 ** 7305 ** ^A virtual table module is created by filling in a persistent 7306 ** instance of this structure and passing a pointer to that instance 7307 ** to [sqlite3_create_module()] or [sqlite3_create_module_v2()]. 7308 ** ^The registration remains valid until it is replaced by a different 7309 ** module or until the [database connection] closes. The content 7310 ** of this structure must not change while it is registered with 7311 ** any database connection. 7312 */ 7313 struct sqlite3_module { 7314 int iVersion; 7315 int (*xCreate)(sqlite3*, void *pAux, 7316 int argc, const char *const*argv, 7317 sqlite3_vtab **ppVTab, char**); 7318 int (*xConnect)(sqlite3*, void *pAux, 7319 int argc, const char *const*argv, 7320 sqlite3_vtab **ppVTab, char**); 7321 int (*xBestIndex)(sqlite3_vtab *pVTab, sqlite3_index_info*); 7322 int (*xDisconnect)(sqlite3_vtab *pVTab); 7323 int (*xDestroy)(sqlite3_vtab *pVTab); 7324 int (*xOpen)(sqlite3_vtab *pVTab, sqlite3_vtab_cursor **ppCursor); 7325 int (*xClose)(sqlite3_vtab_cursor*); 7326 int (*xFilter)(sqlite3_vtab_cursor*, int idxNum, const char *idxStr, 7327 int argc, sqlite3_value **argv); 7328 int (*xNext)(sqlite3_vtab_cursor*); 7329 int (*xEof)(sqlite3_vtab_cursor*); 7330 int (*xColumn)(sqlite3_vtab_cursor*, sqlite3_context*, int); 7331 int (*xRowid)(sqlite3_vtab_cursor*, sqlite3_int64 *pRowid); 7332 int (*xUpdate)(sqlite3_vtab *, int, sqlite3_value **, sqlite3_int64 *); 7333 int (*xBegin)(sqlite3_vtab *pVTab); 7334 int (*xSync)(sqlite3_vtab *pVTab); 7335 int (*xCommit)(sqlite3_vtab *pVTab); 7336 int (*xRollback)(sqlite3_vtab *pVTab); 7337 int (*xFindFunction)(sqlite3_vtab *pVtab, int nArg, const char *zName, 7338 void (**pxFunc)(sqlite3_context*,int,sqlite3_value**), 7339 void **ppArg); 7340 int (*xRename)(sqlite3_vtab *pVtab, const char *zNew); 7341 /* The methods above are in version 1 of the sqlite_module object. Those 7342 ** below are for version 2 and greater. */ 7343 int (*xSavepoint)(sqlite3_vtab *pVTab, int); 7344 int (*xRelease)(sqlite3_vtab *pVTab, int); 7345 int (*xRollbackTo)(sqlite3_vtab *pVTab, int); 7346 /* The methods above are in versions 1 and 2 of the sqlite_module object. 7347 ** Those below are for version 3 and greater. */ 7348 int (*xShadowName)(const char*); 7349 /* The methods above are in versions 1 through 3 of the sqlite_module object. 7350 ** Those below are for version 4 and greater. */ 7351 int (*xIntegrity)(sqlite3_vtab *pVTab, const char *zSchema, 7352 const char *zTabName, int mFlags, char **pzErr); 7353 }; 7354 7355 /* 7356 ** CAPI3REF: Virtual Table Indexing Information 7357 ** KEYWORDS: sqlite3_index_info 7358 ** 7359 ** The sqlite3_index_info structure and its substructures is used as part 7360 ** of the [virtual table] interface to 7361 ** pass information into and receive the reply from the [xBestIndex] 7362 ** method of a [virtual table module]. The fields under **Inputs** are the 7363 ** inputs to xBestIndex and are read-only. xBestIndex inserts its 7364 ** results into the **Outputs** fields. 7365 ** 7366 ** ^(The aConstraint[] array records WHERE clause constraints of the form: 7367 ** 7368 ** <blockquote>column OP expr</blockquote> 7369 ** 7370 ** where OP is =, <, <=, >, or >=.)^ ^(The particular operator is 7371 ** stored in aConstraint[].op using one of the 7372 ** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^ 7373 ** ^(The index of the column is stored in 7374 ** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the 7375 ** expr on the right-hand side can be evaluated (and thus the constraint 7376 ** is usable) and false if it cannot.)^ 7377 ** 7378 ** ^The optimizer automatically inverts terms of the form "expr OP column" 7379 ** and makes other simplifications to the WHERE clause in an attempt to 7380 ** get as many WHERE clause terms into the form shown above as possible. 7381 ** ^The aConstraint[] array only reports WHERE clause terms that are 7382 ** relevant to the particular virtual table being queried. 7383 ** 7384 ** ^Information about the ORDER BY clause is stored in aOrderBy[]. 7385 ** ^Each term of aOrderBy records a column of the ORDER BY clause. 7386 ** 7387 ** The colUsed field indicates which columns of the virtual table may be 7388 ** required by the current scan. Virtual table columns are numbered from 7389 ** zero in the order in which they appear within the CREATE TABLE statement 7390 ** passed to sqlite3_declare_vtab(). For the first 63 columns (columns 0-62), 7391 ** the corresponding bit is set within the colUsed mask if the column may be 7392 ** required by SQLite. If the table has at least 64 columns and any column 7393 ** to the right of the first 63 is required, then bit 63 of colUsed is also 7394 ** set. In other words, column iCol may be required if the expression 7395 ** (colUsed & ((sqlite3_uint64)1 << (iCol>=63 ? 63 : iCol))) evaluates to 7396 ** non-zero. 7397 ** 7398 ** The [xBestIndex] method must fill aConstraintUsage[] with information 7399 ** about what parameters to pass to xFilter. ^If argvIndex>0 then 7400 ** the right-hand side of the corresponding aConstraint[] is evaluated 7401 ** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit 7402 ** is true, then the constraint is assumed to be fully handled by the 7403 ** virtual table and might not be checked again by the byte code.)^ ^(The 7404 ** aConstraintUsage[].omit flag is an optimization hint. When the omit flag 7405 ** is left in its default setting of false, the constraint will always be 7406 ** checked separately in byte code. If the omit flag is change to true, then 7407 ** the constraint may or may not be checked in byte code. In other words, 7408 ** when the omit flag is true there is no guarantee that the constraint will 7409 ** not be checked again using byte code.)^ 7410 ** 7411 ** ^The idxNum and idxStr values are recorded and passed into the 7412 ** [xFilter] method. 7413 ** ^[sqlite3_free()] is used to free idxStr if and only if 7414 ** needToFreeIdxStr is true. 7415 ** 7416 ** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in 7417 ** the correct order to satisfy the ORDER BY clause so that no separate 7418 ** sorting step is required. 7419 ** 7420 ** ^The estimatedCost value is an estimate of the cost of a particular 7421 ** strategy. A cost of N indicates that the cost of the strategy is similar 7422 ** to a linear scan of an SQLite table with N rows. A cost of log(N) 7423 ** indicates that the expense of the operation is similar to that of a 7424 ** binary search on a unique indexed field of an SQLite table with N rows. 7425 ** 7426 ** ^The estimatedRows value is an estimate of the number of rows that 7427 ** will be returned by the strategy. 7428 ** 7429 ** The xBestIndex method may optionally populate the idxFlags field with a 7430 ** mask of SQLITE_INDEX_SCAN_* flags. Currently there is only one such flag - 7431 ** SQLITE_INDEX_SCAN_UNIQUE. If the xBestIndex method sets this flag, SQLite 7432 ** assumes that the strategy may visit at most one row. 7433 ** 7434 ** Additionally, if xBestIndex sets the SQLITE_INDEX_SCAN_UNIQUE flag, then 7435 ** SQLite also assumes that if a call to the xUpdate() method is made as 7436 ** part of the same statement to delete or update a virtual table row and the 7437 ** implementation returns SQLITE_CONSTRAINT, then there is no need to rollback 7438 ** any database changes. In other words, if the xUpdate() returns 7439 ** SQLITE_CONSTRAINT, the database contents must be exactly as they were 7440 ** before xUpdate was called. By contrast, if SQLITE_INDEX_SCAN_UNIQUE is not 7441 ** set and xUpdate returns SQLITE_CONSTRAINT, any database changes made by 7442 ** the xUpdate method are automatically rolled back by SQLite. 7443 ** 7444 ** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info 7445 ** structure for SQLite [version 3.8.2] ([dateof:3.8.2]). 7446 ** If a virtual table extension is 7447 ** used with an SQLite version earlier than 3.8.2, the results of attempting 7448 ** to read or write the estimatedRows field are undefined (but are likely 7449 ** to include crashing the application). The estimatedRows field should 7450 ** therefore only be used if [sqlite3_libversion_number()] returns a 7451 ** value greater than or equal to 3008002. Similarly, the idxFlags field 7452 ** was added for [version 3.9.0] ([dateof:3.9.0]). 7453 ** It may therefore only be used if 7454 ** sqlite3_libversion_number() returns a value greater than or equal to 7455 ** 3009000. 7456 */ 7457 struct sqlite3_index_info { 7458 /* Inputs */ 7459 int nConstraint; /* Number of entries in aConstraint */ 7460 struct sqlite3_index_constraint { 7461 int iColumn; /* Column constrained. -1 for ROWID */ 7462 unsigned char op; /* Constraint operator */ 7463 unsigned char usable; /* True if this constraint is usable */ 7464 int iTermOffset; /* Used internally - xBestIndex should ignore */ 7465 } *aConstraint; /* Table of WHERE clause constraints */ 7466 int nOrderBy; /* Number of terms in the ORDER BY clause */ 7467 struct sqlite3_index_orderby { 7468 int iColumn; /* Column number */ 7469 unsigned char desc; /* True for DESC. False for ASC. */ 7470 } *aOrderBy; /* The ORDER BY clause */ 7471 /* Outputs */ 7472 struct sqlite3_index_constraint_usage { 7473 int argvIndex; /* if >0, constraint is part of argv to xFilter */ 7474 unsigned char omit; /* Do not code a test for this constraint */ 7475 } *aConstraintUsage; 7476 int idxNum; /* Number used to identify the index */ 7477 char *idxStr; /* String, possibly obtained from sqlite3_malloc */ 7478 int needToFreeIdxStr; /* Free idxStr using sqlite3_free() if true */ 7479 int orderByConsumed; /* True if output is already ordered */ 7480 double estimatedCost; /* Estimated cost of using this index */ 7481 /* Fields below are only available in SQLite 3.8.2 and later */ 7482 sqlite3_int64 estimatedRows; /* Estimated number of rows returned */ 7483 /* Fields below are only available in SQLite 3.9.0 and later */ 7484 int idxFlags; /* Mask of SQLITE_INDEX_SCAN_* flags */ 7485 /* Fields below are only available in SQLite 3.10.0 and later */ 7486 sqlite3_uint64 colUsed; /* Input: Mask of columns used by statement */ 7487 }; 7488 7489 /* 7490 ** CAPI3REF: Virtual Table Scan Flags 7491 ** 7492 ** Virtual table implementations are allowed to set the 7493 ** [sqlite3_index_info].idxFlags field to some combination of 7494 ** these bits. 7495 */ 7496 #define SQLITE_INDEX_SCAN_UNIQUE 1 /* Scan visits at most 1 row */ 7497 7498 /* 7499 ** CAPI3REF: Virtual Table Constraint Operator Codes 7500 ** 7501 ** These macros define the allowed values for the 7502 ** [sqlite3_index_info].aConstraint[].op field. Each value represents 7503 ** an operator that is part of a constraint term in the WHERE clause of 7504 ** a query that uses a [virtual table]. 7505 ** 7506 ** ^The left-hand operand of the operator is given by the corresponding 7507 ** aConstraint[].iColumn field. ^An iColumn of -1 indicates the left-hand 7508 ** operand is the rowid. 7509 ** The SQLITE_INDEX_CONSTRAINT_LIMIT and SQLITE_INDEX_CONSTRAINT_OFFSET 7510 ** operators have no left-hand operand, and so for those operators the 7511 ** corresponding aConstraint[].iColumn is meaningless and should not be 7512 ** used. 7513 ** 7514 ** All operator values from SQLITE_INDEX_CONSTRAINT_FUNCTION through 7515 ** value 255 are reserved to represent functions that are overloaded 7516 ** by the [xFindFunction|xFindFunction method] of the virtual table 7517 ** implementation. 7518 ** 7519 ** The right-hand operands for each constraint might be accessible using 7520 ** the [sqlite3_vtab_rhs_value()] interface. Usually the right-hand 7521 ** operand is only available if it appears as a single constant literal 7522 ** in the input SQL. If the right-hand operand is another column or an 7523 ** expression (even a constant expression) or a parameter, then the 7524 ** sqlite3_vtab_rhs_value() probably will not be able to extract it. 7525 ** ^The SQLITE_INDEX_CONSTRAINT_ISNULL and 7526 ** SQLITE_INDEX_CONSTRAINT_ISNOTNULL operators have no right-hand operand 7527 ** and hence calls to sqlite3_vtab_rhs_value() for those operators will 7528 ** always return SQLITE_NOTFOUND. 7529 ** 7530 ** The collating sequence to be used for comparison can be found using 7531 ** the [sqlite3_vtab_collation()] interface. For most real-world virtual 7532 ** tables, the collating sequence of constraints does not matter (for example 7533 ** because the constraints are numeric) and so the sqlite3_vtab_collation() 7534 ** interface is not commonly needed. 7535 */ 7536 #define SQLITE_INDEX_CONSTRAINT_EQ 2 7537 #define SQLITE_INDEX_CONSTRAINT_GT 4 7538 #define SQLITE_INDEX_CONSTRAINT_LE 8 7539 #define SQLITE_INDEX_CONSTRAINT_LT 16 7540 #define SQLITE_INDEX_CONSTRAINT_GE 32 7541 #define SQLITE_INDEX_CONSTRAINT_MATCH 64 7542 #define SQLITE_INDEX_CONSTRAINT_LIKE 65 7543 #define SQLITE_INDEX_CONSTRAINT_GLOB 66 7544 #define SQLITE_INDEX_CONSTRAINT_REGEXP 67 7545 #define SQLITE_INDEX_CONSTRAINT_NE 68 7546 #define SQLITE_INDEX_CONSTRAINT_ISNOT 69 7547 #define SQLITE_INDEX_CONSTRAINT_ISNOTNULL 70 7548 #define SQLITE_INDEX_CONSTRAINT_ISNULL 71 7549 #define SQLITE_INDEX_CONSTRAINT_IS 72 7550 #define SQLITE_INDEX_CONSTRAINT_LIMIT 73 7551 #define SQLITE_INDEX_CONSTRAINT_OFFSET 74 7552 #define SQLITE_INDEX_CONSTRAINT_FUNCTION 150 7553 7554 /* 7555 ** CAPI3REF: Register A Virtual Table Implementation 7556 ** METHOD: sqlite3 7557 ** 7558 ** ^These routines are used to register a new [virtual table module] name. 7559 ** ^Module names must be registered before 7560 ** creating a new [virtual table] using the module and before using a 7561 ** preexisting [virtual table] for the module. 7562 ** 7563 ** ^The module name is registered on the [database connection] specified 7564 ** by the first parameter. ^The name of the module is given by the 7565 ** second parameter. ^The third parameter is a pointer to 7566 ** the implementation of the [virtual table module]. ^The fourth 7567 ** parameter is an arbitrary client data pointer that is passed through 7568 ** into the [xCreate] and [xConnect] methods of the virtual table module 7569 ** when a new virtual table is be being created or reinitialized. 7570 ** 7571 ** ^The sqlite3_create_module_v2() interface has a fifth parameter which 7572 ** is a pointer to a destructor for the pClientData. ^SQLite will 7573 ** invoke the destructor function (if it is not NULL) when SQLite 7574 ** no longer needs the pClientData pointer. ^The destructor will also 7575 ** be invoked if the call to sqlite3_create_module_v2() fails. 7576 ** ^The sqlite3_create_module() 7577 ** interface is equivalent to sqlite3_create_module_v2() with a NULL 7578 ** destructor. 7579 ** 7580 ** ^If the third parameter (the pointer to the sqlite3_module object) is 7581 ** NULL then no new module is created and any existing modules with the 7582 ** same name are dropped. 7583 ** 7584 ** See also: [sqlite3_drop_modules()] 7585 */ 7586 SQLITE_API int sqlite3_create_module( 7587 sqlite3 *db, /* SQLite connection to register module with */ 7588 const char *zName, /* Name of the module */ 7589 const sqlite3_module *p, /* Methods for the module */ 7590 void *pClientData /* Client data for xCreate/xConnect */ 7591 ); 7592 SQLITE_API int sqlite3_create_module_v2( 7593 sqlite3 *db, /* SQLite connection to register module with */ 7594 const char *zName, /* Name of the module */ 7595 const sqlite3_module *p, /* Methods for the module */ 7596 void *pClientData, /* Client data for xCreate/xConnect */ 7597 void(*xDestroy)(void*) /* Module destructor function */ 7598 ); 7599 7600 /* 7601 ** CAPI3REF: Remove Unnecessary Virtual Table Implementations 7602 ** METHOD: sqlite3 7603 ** 7604 ** ^The sqlite3_drop_modules(D,L) interface removes all virtual 7605 ** table modules from database connection D except those named on list L. 7606 ** The L parameter must be either NULL or a pointer to an array of pointers 7607 ** to strings where the array is terminated by a single NULL pointer. 7608 ** ^If the L parameter is NULL, then all virtual table modules are removed. 7609 ** 7610 ** See also: [sqlite3_create_module()] 7611 */ 7612 SQLITE_API int sqlite3_drop_modules( 7613 sqlite3 *db, /* Remove modules from this connection */ 7614 const char **azKeep /* Except, do not remove the ones named here */ 7615 ); 7616 7617 /* 7618 ** CAPI3REF: Virtual Table Instance Object 7619 ** KEYWORDS: sqlite3_vtab 7620 ** 7621 ** Every [virtual table module] implementation uses a subclass 7622 ** of this object to describe a particular instance 7623 ** of the [virtual table]. Each subclass will 7624 ** be tailored to the specific needs of the module implementation. 7625 ** The purpose of this superclass is to define certain fields that are 7626 ** common to all module implementations. 7627 ** 7628 ** ^Virtual tables methods can set an error message by assigning a 7629 ** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should 7630 ** take care that any prior string is freed by a call to [sqlite3_free()] 7631 ** prior to assigning a new string to zErrMsg. ^After the error message 7632 ** is delivered up to the client application, the string will be automatically 7633 ** freed by sqlite3_free() and the zErrMsg field will be zeroed. 7634 */ 7635 struct sqlite3_vtab { 7636 const sqlite3_module *pModule; /* The module for this virtual table */ 7637 int nRef; /* Number of open cursors */ 7638 char *zErrMsg; /* Error message from sqlite3_mprintf() */ 7639 /* Virtual table implementations will typically add additional fields */ 7640 }; 7641 7642 /* 7643 ** CAPI3REF: Virtual Table Cursor Object 7644 ** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor} 7645 ** 7646 ** Every [virtual table module] implementation uses a subclass of the 7647 ** following structure to describe cursors that point into the 7648 ** [virtual table] and are used 7649 ** to loop through the virtual table. Cursors are created using the 7650 ** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed 7651 ** by the [sqlite3_module.xClose | xClose] method. Cursors are used 7652 ** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods 7653 ** of the module. Each module implementation will define 7654 ** the content of a cursor structure to suit its own needs. 7655 ** 7656 ** This superclass exists in order to define fields of the cursor that 7657 ** are common to all implementations. 7658 */ 7659 struct sqlite3_vtab_cursor { 7660 sqlite3_vtab *pVtab; /* Virtual table of this cursor */ 7661 /* Virtual table implementations will typically add additional fields */ 7662 }; 7663 7664 /* 7665 ** CAPI3REF: Declare The Schema Of A Virtual Table 7666 ** 7667 ** ^The [xCreate] and [xConnect] methods of a 7668 ** [virtual table module] call this interface 7669 ** to declare the format (the names and datatypes of the columns) of 7670 ** the virtual tables they implement. 7671 */ 7672 SQLITE_API int sqlite3_declare_vtab(sqlite3*, const char *zSQL); 7673 7674 /* 7675 ** CAPI3REF: Overload A Function For A Virtual Table 7676 ** METHOD: sqlite3 7677 ** 7678 ** ^(Virtual tables can provide alternative implementations of functions 7679 ** using the [xFindFunction] method of the [virtual table module]. 7680 ** But global versions of those functions 7681 ** must exist in order to be overloaded.)^ 7682 ** 7683 ** ^(This API makes sure a global version of a function with a particular 7684 ** name and number of parameters exists. If no such function exists 7685 ** before this API is called, a new function is created.)^ ^The implementation 7686 ** of the new function always causes an exception to be thrown. So 7687 ** the new function is not good for anything by itself. Its only 7688 ** purpose is to be a placeholder function that can be overloaded 7689 ** by a [virtual table]. 7690 */ 7691 SQLITE_API int sqlite3_overload_function(sqlite3*, const char *zFuncName, int nArg); 7692 7693 /* 7694 ** CAPI3REF: A Handle To An Open BLOB 7695 ** KEYWORDS: {BLOB handle} {BLOB handles} 7696 ** 7697 ** An instance of this object represents an open BLOB on which 7698 ** [sqlite3_blob_open | incremental BLOB I/O] can be performed. 7699 ** ^Objects of this type are created by [sqlite3_blob_open()] 7700 ** and destroyed by [sqlite3_blob_close()]. 7701 ** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces 7702 ** can be used to read or write small subsections of the BLOB. 7703 ** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes. 7704 */ 7705 typedef struct sqlite3_blob sqlite3_blob; 7706 7707 /* 7708 ** CAPI3REF: Open A BLOB For Incremental I/O 7709 ** METHOD: sqlite3 7710 ** CONSTRUCTOR: sqlite3_blob 7711 ** 7712 ** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located 7713 ** in row iRow, column zColumn, table zTable in database zDb; 7714 ** in other words, the same BLOB that would be selected by: 7715 ** 7716 ** <pre> 7717 ** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow; 7718 ** </pre>)^ 7719 ** 7720 ** ^(Parameter zDb is not the filename that contains the database, but 7721 ** rather the symbolic name of the database. For attached databases, this is 7722 ** the name that appears after the AS keyword in the [ATTACH] statement. 7723 ** For the main database file, the database name is "main". For TEMP 7724 ** tables, the database name is "temp".)^ 7725 ** 7726 ** ^If the flags parameter is non-zero, then the BLOB is opened for read 7727 ** and write access. ^If the flags parameter is zero, the BLOB is opened for 7728 ** read-only access. 7729 ** 7730 ** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is stored 7731 ** in *ppBlob. Otherwise an [error code] is returned and, unless the error 7732 ** code is SQLITE_MISUSE, *ppBlob is set to NULL.)^ ^This means that, provided 7733 ** the API is not misused, it is always safe to call [sqlite3_blob_close()] 7734 ** on *ppBlob after this function it returns. 7735 ** 7736 ** This function fails with SQLITE_ERROR if any of the following are true: 7737 ** <ul> 7738 ** <li> ^(Database zDb does not exist)^, 7739 ** <li> ^(Table zTable does not exist within database zDb)^, 7740 ** <li> ^(Table zTable is a WITHOUT ROWID table)^, 7741 ** <li> ^(Column zColumn does not exist)^, 7742 ** <li> ^(Row iRow is not present in the table)^, 7743 ** <li> ^(The specified column of row iRow contains a value that is not 7744 ** a TEXT or BLOB value)^, 7745 ** <li> ^(Column zColumn is part of an index, PRIMARY KEY or UNIQUE 7746 ** constraint and the blob is being opened for read/write access)^, 7747 ** <li> ^([foreign key constraints | Foreign key constraints] are enabled, 7748 ** column zColumn is part of a [child key] definition and the blob is 7749 ** being opened for read/write access)^. 7750 ** </ul> 7751 ** 7752 ** ^Unless it returns SQLITE_MISUSE, this function sets the 7753 ** [database connection] error code and message accessible via 7754 ** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. 7755 ** 7756 ** A BLOB referenced by sqlite3_blob_open() may be read using the 7757 ** [sqlite3_blob_read()] interface and modified by using 7758 ** [sqlite3_blob_write()]. The [BLOB handle] can be moved to a 7759 ** different row of the same table using the [sqlite3_blob_reopen()] 7760 ** interface. However, the column, table, or database of a [BLOB handle] 7761 ** cannot be changed after the [BLOB handle] is opened. 7762 ** 7763 ** ^(If the row that a BLOB handle points to is modified by an 7764 ** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects 7765 ** then the BLOB handle is marked as "expired". 7766 ** This is true if any column of the row is changed, even a column 7767 ** other than the one the BLOB handle is open on.)^ 7768 ** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for 7769 ** an expired BLOB handle fail with a return code of [SQLITE_ABORT]. 7770 ** ^(Changes written into a BLOB prior to the BLOB expiring are not 7771 ** rolled back by the expiration of the BLOB. Such changes will eventually 7772 ** commit if the transaction continues to completion.)^ 7773 ** 7774 ** ^Use the [sqlite3_blob_bytes()] interface to determine the size of 7775 ** the opened blob. ^The size of a blob may not be changed by this 7776 ** interface. Use the [UPDATE] SQL command to change the size of a 7777 ** blob. 7778 ** 7779 ** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces 7780 ** and the built-in [zeroblob] SQL function may be used to create a 7781 ** zero-filled blob to read or write using the incremental-blob interface. 7782 ** 7783 ** To avoid a resource leak, every open [BLOB handle] should eventually 7784 ** be released by a call to [sqlite3_blob_close()]. 7785 ** 7786 ** See also: [sqlite3_blob_close()], 7787 ** [sqlite3_blob_reopen()], [sqlite3_blob_read()], 7788 ** [sqlite3_blob_bytes()], [sqlite3_blob_write()]. 7789 */ 7790 SQLITE_API int sqlite3_blob_open( 7791 sqlite3*, 7792 const char *zDb, 7793 const char *zTable, 7794 const char *zColumn, 7795 sqlite3_int64 iRow, 7796 int flags, 7797 sqlite3_blob **ppBlob 7798 ); 7799 7800 /* 7801 ** CAPI3REF: Move a BLOB Handle to a New Row 7802 ** METHOD: sqlite3_blob 7803 ** 7804 ** ^This function is used to move an existing [BLOB handle] so that it points 7805 ** to a different row of the same database table. ^The new row is identified 7806 ** by the rowid value passed as the second argument. Only the row can be 7807 ** changed. ^The database, table and column on which the blob handle is open 7808 ** remain the same. Moving an existing [BLOB handle] to a new row is 7809 ** faster than closing the existing handle and opening a new one. 7810 ** 7811 ** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] - 7812 ** it must exist and there must be either a blob or text value stored in 7813 ** the nominated column.)^ ^If the new row is not present in the table, or if 7814 ** it does not contain a blob or text value, or if another error occurs, an 7815 ** SQLite error code is returned and the blob handle is considered aborted. 7816 ** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or 7817 ** [sqlite3_blob_reopen()] on an aborted blob handle immediately return 7818 ** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle 7819 ** always returns zero. 7820 ** 7821 ** ^This function sets the database handle error code and message. 7822 */ 7823 SQLITE_API int sqlite3_blob_reopen(sqlite3_blob *, sqlite3_int64); 7824 7825 /* 7826 ** CAPI3REF: Close A BLOB Handle 7827 ** DESTRUCTOR: sqlite3_blob 7828 ** 7829 ** ^This function closes an open [BLOB handle]. ^(The BLOB handle is closed 7830 ** unconditionally. Even if this routine returns an error code, the 7831 ** handle is still closed.)^ 7832 ** 7833 ** ^If the blob handle being closed was opened for read-write access, and if 7834 ** the database is in auto-commit mode and there are no other open read-write 7835 ** blob handles or active write statements, the current transaction is 7836 ** committed. ^If an error occurs while committing the transaction, an error 7837 ** code is returned and the transaction rolled back. 7838 ** 7839 ** Calling this function with an argument that is not a NULL pointer or an 7840 ** open blob handle results in undefined behavior. ^Calling this routine 7841 ** with a null pointer (such as would be returned by a failed call to 7842 ** [sqlite3_blob_open()]) is a harmless no-op. ^Otherwise, if this function 7843 ** is passed a valid open blob handle, the values returned by the 7844 ** sqlite3_errcode() and sqlite3_errmsg() functions are set before returning. 7845 */ 7846 SQLITE_API int sqlite3_blob_close(sqlite3_blob *); 7847 7848 /* 7849 ** CAPI3REF: Return The Size Of An Open BLOB 7850 ** METHOD: sqlite3_blob 7851 ** 7852 ** ^Returns the size in bytes of the BLOB accessible via the 7853 ** successfully opened [BLOB handle] in its only argument. ^The 7854 ** incremental blob I/O routines can only read or overwriting existing 7855 ** blob content; they cannot change the size of a blob. 7856 ** 7857 ** This routine only works on a [BLOB handle] which has been created 7858 ** by a prior successful call to [sqlite3_blob_open()] and which has not 7859 ** been closed by [sqlite3_blob_close()]. Passing any other pointer in 7860 ** to this routine results in undefined and probably undesirable behavior. 7861 */ 7862 SQLITE_API int sqlite3_blob_bytes(sqlite3_blob *); 7863 7864 /* 7865 ** CAPI3REF: Read Data From A BLOB Incrementally 7866 ** METHOD: sqlite3_blob 7867 ** 7868 ** ^(This function is used to read data from an open [BLOB handle] into a 7869 ** caller-supplied buffer. N bytes of data are copied into buffer Z 7870 ** from the open BLOB, starting at offset iOffset.)^ 7871 ** 7872 ** ^If offset iOffset is less than N bytes from the end of the BLOB, 7873 ** [SQLITE_ERROR] is returned and no data is read. ^If N or iOffset is 7874 ** less than zero, [SQLITE_ERROR] is returned and no data is read. 7875 ** ^The size of the blob (and hence the maximum value of N+iOffset) 7876 ** can be determined using the [sqlite3_blob_bytes()] interface. 7877 ** 7878 ** ^An attempt to read from an expired [BLOB handle] fails with an 7879 ** error code of [SQLITE_ABORT]. 7880 ** 7881 ** ^(On success, sqlite3_blob_read() returns SQLITE_OK. 7882 ** Otherwise, an [error code] or an [extended error code] is returned.)^ 7883 ** 7884 ** This routine only works on a [BLOB handle] which has been created 7885 ** by a prior successful call to [sqlite3_blob_open()] and which has not 7886 ** been closed by [sqlite3_blob_close()]. Passing any other pointer in 7887 ** to this routine results in undefined and probably undesirable behavior. 7888 ** 7889 ** See also: [sqlite3_blob_write()]. 7890 */ 7891 SQLITE_API int sqlite3_blob_read(sqlite3_blob *, void *Z, int N, int iOffset); 7892 7893 /* 7894 ** CAPI3REF: Write Data Into A BLOB Incrementally 7895 ** METHOD: sqlite3_blob 7896 ** 7897 ** ^(This function is used to write data into an open [BLOB handle] from a 7898 ** caller-supplied buffer. N bytes of data are copied from the buffer Z 7899 ** into the open BLOB, starting at offset iOffset.)^ 7900 ** 7901 ** ^(On success, sqlite3_blob_write() returns SQLITE_OK. 7902 ** Otherwise, an [error code] or an [extended error code] is returned.)^ 7903 ** ^Unless SQLITE_MISUSE is returned, this function sets the 7904 ** [database connection] error code and message accessible via 7905 ** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. 7906 ** 7907 ** ^If the [BLOB handle] passed as the first argument was not opened for 7908 ** writing (the flags parameter to [sqlite3_blob_open()] was zero), 7909 ** this function returns [SQLITE_READONLY]. 7910 ** 7911 ** This function may only modify the contents of the BLOB; it is 7912 ** not possible to increase the size of a BLOB using this API. 7913 ** ^If offset iOffset is less than N bytes from the end of the BLOB, 7914 ** [SQLITE_ERROR] is returned and no data is written. The size of the 7915 ** BLOB (and hence the maximum value of N+iOffset) can be determined 7916 ** using the [sqlite3_blob_bytes()] interface. ^If N or iOffset are less 7917 ** than zero [SQLITE_ERROR] is returned and no data is written. 7918 ** 7919 ** ^An attempt to write to an expired [BLOB handle] fails with an 7920 ** error code of [SQLITE_ABORT]. ^Writes to the BLOB that occurred 7921 ** before the [BLOB handle] expired are not rolled back by the 7922 ** expiration of the handle, though of course those changes might 7923 ** have been overwritten by the statement that expired the BLOB handle 7924 ** or by other independent statements. 7925 ** 7926 ** This routine only works on a [BLOB handle] which has been created 7927 ** by a prior successful call to [sqlite3_blob_open()] and which has not 7928 ** been closed by [sqlite3_blob_close()]. Passing any other pointer in 7929 ** to this routine results in undefined and probably undesirable behavior. 7930 ** 7931 ** See also: [sqlite3_blob_read()]. 7932 */ 7933 SQLITE_API int sqlite3_blob_write(sqlite3_blob *, const void *z, int n, int iOffset); 7934 7935 /* 7936 ** CAPI3REF: Virtual File System Objects 7937 ** 7938 ** A virtual filesystem (VFS) is an [sqlite3_vfs] object 7939 ** that SQLite uses to interact 7940 ** with the underlying operating system. Most SQLite builds come with a 7941 ** single default VFS that is appropriate for the host computer. 7942 ** New VFSes can be registered and existing VFSes can be unregistered. 7943 ** The following interfaces are provided. 7944 ** 7945 ** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name. 7946 ** ^Names are case sensitive. 7947 ** ^Names are zero-terminated UTF-8 strings. 7948 ** ^If there is no match, a NULL pointer is returned. 7949 ** ^If zVfsName is NULL then the default VFS is returned. 7950 ** 7951 ** ^New VFSes are registered with sqlite3_vfs_register(). 7952 ** ^Each new VFS becomes the default VFS if the makeDflt flag is set. 7953 ** ^The same VFS can be registered multiple times without injury. 7954 ** ^To make an existing VFS into the default VFS, register it again 7955 ** with the makeDflt flag set. If two different VFSes with the 7956 ** same name are registered, the behavior is undefined. If a 7957 ** VFS is registered with a name that is NULL or an empty string, 7958 ** then the behavior is undefined. 7959 ** 7960 ** ^Unregister a VFS with the sqlite3_vfs_unregister() interface. 7961 ** ^(If the default VFS is unregistered, another VFS is chosen as 7962 ** the default. The choice for the new VFS is arbitrary.)^ 7963 */ 7964 SQLITE_API sqlite3_vfs *sqlite3_vfs_find(const char *zVfsName); 7965 SQLITE_API int sqlite3_vfs_register(sqlite3_vfs*, int makeDflt); 7966 SQLITE_API int sqlite3_vfs_unregister(sqlite3_vfs*); 7967 7968 /* 7969 ** CAPI3REF: Mutexes 7970 ** 7971 ** The SQLite core uses these routines for thread 7972 ** synchronization. Though they are intended for internal 7973 ** use by SQLite, code that links against SQLite is 7974 ** permitted to use any of these routines. 7975 ** 7976 ** The SQLite source code contains multiple implementations 7977 ** of these mutex routines. An appropriate implementation 7978 ** is selected automatically at compile-time. The following 7979 ** implementations are available in the SQLite core: 7980 ** 7981 ** <ul> 7982 ** <li> SQLITE_MUTEX_PTHREADS 7983 ** <li> SQLITE_MUTEX_W32 7984 ** <li> SQLITE_MUTEX_NOOP 7985 ** </ul> 7986 ** 7987 ** The SQLITE_MUTEX_NOOP implementation is a set of routines 7988 ** that does no real locking and is appropriate for use in 7989 ** a single-threaded application. The SQLITE_MUTEX_PTHREADS and 7990 ** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix 7991 ** and Windows. 7992 ** 7993 ** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor 7994 ** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex 7995 ** implementation is included with the library. In this case the 7996 ** application must supply a custom mutex implementation using the 7997 ** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function 7998 ** before calling sqlite3_initialize() or any other public sqlite3_ 7999 ** function that calls sqlite3_initialize(). 8000 ** 8001 ** ^The sqlite3_mutex_alloc() routine allocates a new 8002 ** mutex and returns a pointer to it. ^The sqlite3_mutex_alloc() 8003 ** routine returns NULL if it is unable to allocate the requested 8004 ** mutex. The argument to sqlite3_mutex_alloc() must one of these 8005 ** integer constants: 8006 ** 8007 ** <ul> 8008 ** <li> SQLITE_MUTEX_FAST 8009 ** <li> SQLITE_MUTEX_RECURSIVE 8010 ** <li> SQLITE_MUTEX_STATIC_MAIN 8011 ** <li> SQLITE_MUTEX_STATIC_MEM 8012 ** <li> SQLITE_MUTEX_STATIC_OPEN 8013 ** <li> SQLITE_MUTEX_STATIC_PRNG 8014 ** <li> SQLITE_MUTEX_STATIC_LRU 8015 ** <li> SQLITE_MUTEX_STATIC_PMEM 8016 ** <li> SQLITE_MUTEX_STATIC_APP1 8017 ** <li> SQLITE_MUTEX_STATIC_APP2 8018 ** <li> SQLITE_MUTEX_STATIC_APP3 8019 ** <li> SQLITE_MUTEX_STATIC_VFS1 8020 ** <li> SQLITE_MUTEX_STATIC_VFS2 8021 ** <li> SQLITE_MUTEX_STATIC_VFS3 8022 ** </ul> 8023 ** 8024 ** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) 8025 ** cause sqlite3_mutex_alloc() to create 8026 ** a new mutex. ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE 8027 ** is used but not necessarily so when SQLITE_MUTEX_FAST is used. 8028 ** The mutex implementation does not need to make a distinction 8029 ** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does 8030 ** not want to. SQLite will only request a recursive mutex in 8031 ** cases where it really needs one. If a faster non-recursive mutex 8032 ** implementation is available on the host platform, the mutex subsystem 8033 ** might return such a mutex in response to SQLITE_MUTEX_FAST. 8034 ** 8035 ** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other 8036 ** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return 8037 ** a pointer to a static preexisting mutex. ^Nine static mutexes are 8038 ** used by the current version of SQLite. Future versions of SQLite 8039 ** may add additional static mutexes. Static mutexes are for internal 8040 ** use by SQLite only. Applications that use SQLite mutexes should 8041 ** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or 8042 ** SQLITE_MUTEX_RECURSIVE. 8043 ** 8044 ** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST 8045 ** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc() 8046 ** returns a different mutex on every call. ^For the static 8047 ** mutex types, the same mutex is returned on every call that has 8048 ** the same type number. 8049 ** 8050 ** ^The sqlite3_mutex_free() routine deallocates a previously 8051 ** allocated dynamic mutex. Attempting to deallocate a static 8052 ** mutex results in undefined behavior. 8053 ** 8054 ** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt 8055 ** to enter a mutex. ^If another thread is already within the mutex, 8056 ** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return 8057 ** SQLITE_BUSY. ^The sqlite3_mutex_try() interface returns [SQLITE_OK] 8058 ** upon successful entry. ^(Mutexes created using 8059 ** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread. 8060 ** In such cases, the 8061 ** mutex must be exited an equal number of times before another thread 8062 ** can enter.)^ If the same thread tries to enter any mutex other 8063 ** than an SQLITE_MUTEX_RECURSIVE more than once, the behavior is undefined. 8064 ** 8065 ** ^(Some systems (for example, Windows 95) do not support the operation 8066 ** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try() 8067 ** will always return SQLITE_BUSY. In most cases the SQLite core only uses 8068 ** sqlite3_mutex_try() as an optimization, so this is acceptable 8069 ** behavior. The exceptions are unix builds that set the 8070 ** SQLITE_ENABLE_SETLK_TIMEOUT build option. In that case a working 8071 ** sqlite3_mutex_try() is required.)^ 8072 ** 8073 ** ^The sqlite3_mutex_leave() routine exits a mutex that was 8074 ** previously entered by the same thread. The behavior 8075 ** is undefined if the mutex is not currently entered by the 8076 ** calling thread or is not currently allocated. 8077 ** 8078 ** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), 8079 ** sqlite3_mutex_leave(), or sqlite3_mutex_free() is a NULL pointer, 8080 ** then any of the four routines behaves as a no-op. 8081 ** 8082 ** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()]. 8083 */ 8084 SQLITE_API sqlite3_mutex *sqlite3_mutex_alloc(int); 8085 SQLITE_API void sqlite3_mutex_free(sqlite3_mutex*); 8086 SQLITE_API void sqlite3_mutex_enter(sqlite3_mutex*); 8087 SQLITE_API int sqlite3_mutex_try(sqlite3_mutex*); 8088 SQLITE_API void sqlite3_mutex_leave(sqlite3_mutex*); 8089 8090 /* 8091 ** CAPI3REF: Mutex Methods Object 8092 ** 8093 ** An instance of this structure defines the low-level routines 8094 ** used to allocate and use mutexes. 8095 ** 8096 ** Usually, the default mutex implementations provided by SQLite are 8097 ** sufficient, however the application has the option of substituting a custom 8098 ** implementation for specialized deployments or systems for which SQLite 8099 ** does not provide a suitable implementation. In this case, the application 8100 ** creates and populates an instance of this structure to pass 8101 ** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option. 8102 ** Additionally, an instance of this structure can be used as an 8103 ** output variable when querying the system for the current mutex 8104 ** implementation, using the [SQLITE_CONFIG_GETMUTEX] option. 8105 ** 8106 ** ^The xMutexInit method defined by this structure is invoked as 8107 ** part of system initialization by the sqlite3_initialize() function. 8108 ** ^The xMutexInit routine is called by SQLite exactly once for each 8109 ** effective call to [sqlite3_initialize()]. 8110 ** 8111 ** ^The xMutexEnd method defined by this structure is invoked as 8112 ** part of system shutdown by the sqlite3_shutdown() function. The 8113 ** implementation of this method is expected to release all outstanding 8114 ** resources obtained by the mutex methods implementation, especially 8115 ** those obtained by the xMutexInit method. ^The xMutexEnd() 8116 ** interface is invoked exactly once for each call to [sqlite3_shutdown()]. 8117 ** 8118 ** ^(The remaining seven methods defined by this structure (xMutexAlloc, 8119 ** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and 8120 ** xMutexNotheld) implement the following interfaces (respectively): 8121 ** 8122 ** <ul> 8123 ** <li> [sqlite3_mutex_alloc()] </li> 8124 ** <li> [sqlite3_mutex_free()] </li> 8125 ** <li> [sqlite3_mutex_enter()] </li> 8126 ** <li> [sqlite3_mutex_try()] </li> 8127 ** <li> [sqlite3_mutex_leave()] </li> 8128 ** <li> [sqlite3_mutex_held()] </li> 8129 ** <li> [sqlite3_mutex_notheld()] </li> 8130 ** </ul>)^ 8131 ** 8132 ** The only difference is that the public sqlite3_XXX functions enumerated 8133 ** above silently ignore any invocations that pass a NULL pointer instead 8134 ** of a valid mutex handle. The implementations of the methods defined 8135 ** by this structure are not required to handle this case. The results 8136 ** of passing a NULL pointer instead of a valid mutex handle are undefined 8137 ** (i.e. it is acceptable to provide an implementation that segfaults if 8138 ** it is passed a NULL pointer). 8139 ** 8140 ** The xMutexInit() method must be threadsafe. It must be harmless to 8141 ** invoke xMutexInit() multiple times within the same process and without 8142 ** intervening calls to xMutexEnd(). Second and subsequent calls to 8143 ** xMutexInit() must be no-ops. 8144 ** 8145 ** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()] 8146 ** and its associates). Similarly, xMutexAlloc() must not use SQLite memory 8147 ** allocation for a static mutex. ^However xMutexAlloc() may use SQLite 8148 ** memory allocation for a fast or recursive mutex. 8149 ** 8150 ** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is 8151 ** called, but only if the prior call to xMutexInit returned SQLITE_OK. 8152 ** If xMutexInit fails in any way, it is expected to clean up after itself 8153 ** prior to returning. 8154 */ 8155 typedef struct sqlite3_mutex_methods sqlite3_mutex_methods; 8156 struct sqlite3_mutex_methods { 8157 int (*xMutexInit)(void); 8158 int (*xMutexEnd)(void); 8159 sqlite3_mutex *(*xMutexAlloc)(int); 8160 void (*xMutexFree)(sqlite3_mutex *); 8161 void (*xMutexEnter)(sqlite3_mutex *); 8162 int (*xMutexTry)(sqlite3_mutex *); 8163 void (*xMutexLeave)(sqlite3_mutex *); 8164 int (*xMutexHeld)(sqlite3_mutex *); 8165 int (*xMutexNotheld)(sqlite3_mutex *); 8166 }; 8167 8168 /* 8169 ** CAPI3REF: Mutex Verification Routines 8170 ** 8171 ** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines 8172 ** are intended for use inside assert() statements. The SQLite core 8173 ** never uses these routines except inside an assert() and applications 8174 ** are advised to follow the lead of the core. The SQLite core only 8175 ** provides implementations for these routines when it is compiled 8176 ** with the SQLITE_DEBUG flag. External mutex implementations 8177 ** are only required to provide these routines if SQLITE_DEBUG is 8178 ** defined and if NDEBUG is not defined. 8179 ** 8180 ** These routines should return true if the mutex in their argument 8181 ** is held or not held, respectively, by the calling thread. 8182 ** 8183 ** The implementation is not required to provide versions of these 8184 ** routines that actually work. If the implementation does not provide working 8185 ** versions of these routines, it should at least provide stubs that always 8186 ** return true so that one does not get spurious assertion failures. 8187 ** 8188 ** If the argument to sqlite3_mutex_held() is a NULL pointer then 8189 ** the routine should return 1. This seems counter-intuitive since 8190 ** clearly the mutex cannot be held if it does not exist. But 8191 ** the reason the mutex does not exist is because the build is not 8192 ** using mutexes. And we do not want the assert() containing the 8193 ** call to sqlite3_mutex_held() to fail, so a non-zero return is 8194 ** the appropriate thing to do. The sqlite3_mutex_notheld() 8195 ** interface should also return 1 when given a NULL pointer. 8196 */ 8197 #ifndef NDEBUG 8198 SQLITE_API int sqlite3_mutex_held(sqlite3_mutex*); 8199 SQLITE_API int sqlite3_mutex_notheld(sqlite3_mutex*); 8200 #endif 8201 8202 /* 8203 ** CAPI3REF: Mutex Types 8204 ** 8205 ** The [sqlite3_mutex_alloc()] interface takes a single argument 8206 ** which is one of these integer constants. 8207 ** 8208 ** The set of static mutexes may change from one SQLite release to the 8209 ** next. Applications that override the built-in mutex logic must be 8210 ** prepared to accommodate additional static mutexes. 8211 */ 8212 #define SQLITE_MUTEX_FAST 0 8213 #define SQLITE_MUTEX_RECURSIVE 1 8214 #define SQLITE_MUTEX_STATIC_MAIN 2 8215 #define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */ 8216 #define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */ 8217 #define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */ 8218 #define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_randomness() */ 8219 #define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */ 8220 #define SQLITE_MUTEX_STATIC_LRU2 7 /* NOT USED */ 8221 #define SQLITE_MUTEX_STATIC_PMEM 7 /* sqlite3PageMalloc() */ 8222 #define SQLITE_MUTEX_STATIC_APP1 8 /* For use by application */ 8223 #define SQLITE_MUTEX_STATIC_APP2 9 /* For use by application */ 8224 #define SQLITE_MUTEX_STATIC_APP3 10 /* For use by application */ 8225 #define SQLITE_MUTEX_STATIC_VFS1 11 /* For use by built-in VFS */ 8226 #define SQLITE_MUTEX_STATIC_VFS2 12 /* For use by extension VFS */ 8227 #define SQLITE_MUTEX_STATIC_VFS3 13 /* For use by application VFS */ 8228 8229 /* Legacy compatibility: */ 8230 #define SQLITE_MUTEX_STATIC_MASTER 2 8231 8232 8233 /* 8234 ** CAPI3REF: Retrieve the mutex for a database connection 8235 ** METHOD: sqlite3 8236 ** 8237 ** ^This interface returns a pointer the [sqlite3_mutex] object that 8238 ** serializes access to the [database connection] given in the argument 8239 ** when the [threading mode] is Serialized. 8240 ** ^If the [threading mode] is Single-thread or Multi-thread then this 8241 ** routine returns a NULL pointer. 8242 */ 8243 SQLITE_API sqlite3_mutex *sqlite3_db_mutex(sqlite3*); 8244 8245 /* 8246 ** CAPI3REF: Low-Level Control Of Database Files 8247 ** METHOD: sqlite3 8248 ** KEYWORDS: {file control} 8249 ** 8250 ** ^The [sqlite3_file_control()] interface makes a direct call to the 8251 ** xFileControl method for the [sqlite3_io_methods] object associated 8252 ** with a particular database identified by the second argument. ^The 8253 ** name of the database is "main" for the main database or "temp" for the 8254 ** TEMP database, or the name that appears after the AS keyword for 8255 ** databases that are added using the [ATTACH] SQL command. 8256 ** ^A NULL pointer can be used in place of "main" to refer to the 8257 ** main database file. 8258 ** ^The third and fourth parameters to this routine 8259 ** are passed directly through to the second and third parameters of 8260 ** the xFileControl method. ^The return value of the xFileControl 8261 ** method becomes the return value of this routine. 8262 ** 8263 ** A few opcodes for [sqlite3_file_control()] are handled directly 8264 ** by the SQLite core and never invoke the 8265 ** sqlite3_io_methods.xFileControl method. 8266 ** ^The [SQLITE_FCNTL_FILE_POINTER] value for the op parameter causes 8267 ** a pointer to the underlying [sqlite3_file] object to be written into 8268 ** the space pointed to by the 4th parameter. The 8269 ** [SQLITE_FCNTL_JOURNAL_POINTER] works similarly except that it returns 8270 ** the [sqlite3_file] object associated with the journal file instead of 8271 ** the main database. The [SQLITE_FCNTL_VFS_POINTER] opcode returns 8272 ** a pointer to the underlying [sqlite3_vfs] object for the file. 8273 ** The [SQLITE_FCNTL_DATA_VERSION] returns the data version counter 8274 ** from the pager. 8275 ** 8276 ** ^If the second parameter (zDbName) does not match the name of any 8277 ** open database file, then SQLITE_ERROR is returned. ^This error 8278 ** code is not remembered and will not be recalled by [sqlite3_errcode()] 8279 ** or [sqlite3_errmsg()]. The underlying xFileControl method might 8280 ** also return SQLITE_ERROR. There is no way to distinguish between 8281 ** an incorrect zDbName and an SQLITE_ERROR return from the underlying 8282 ** xFileControl method. 8283 ** 8284 ** See also: [file control opcodes] 8285 */ 8286 SQLITE_API int sqlite3_file_control(sqlite3*, const char *zDbName, int op, void*); 8287 8288 /* 8289 ** CAPI3REF: Testing Interface 8290 ** 8291 ** ^The sqlite3_test_control() interface is used to read out internal 8292 ** state of SQLite and to inject faults into SQLite for testing 8293 ** purposes. ^The first parameter is an operation code that determines 8294 ** the number, meaning, and operation of all subsequent parameters. 8295 ** 8296 ** This interface is not for use by applications. It exists solely 8297 ** for verifying the correct operation of the SQLite library. Depending 8298 ** on how the SQLite library is compiled, this interface might not exist. 8299 ** 8300 ** The details of the operation codes, their meanings, the parameters 8301 ** they take, and what they do are all subject to change without notice. 8302 ** Unlike most of the SQLite API, this function is not guaranteed to 8303 ** operate consistently from one release to the next. 8304 */ 8305 SQLITE_API int sqlite3_test_control(int op, ...); 8306 8307 /* 8308 ** CAPI3REF: Testing Interface Operation Codes 8309 ** 8310 ** These constants are the valid operation code parameters used 8311 ** as the first argument to [sqlite3_test_control()]. 8312 ** 8313 ** These parameters and their meanings are subject to change 8314 ** without notice. These values are for testing purposes only. 8315 ** Applications should not use any of these parameters or the 8316 ** [sqlite3_test_control()] interface. 8317 */ 8318 #define SQLITE_TESTCTRL_FIRST 5 8319 #define SQLITE_TESTCTRL_PRNG_SAVE 5 8320 #define SQLITE_TESTCTRL_PRNG_RESTORE 6 8321 #define SQLITE_TESTCTRL_PRNG_RESET 7 /* NOT USED */ 8322 #define SQLITE_TESTCTRL_FK_NO_ACTION 7 8323 #define SQLITE_TESTCTRL_BITVEC_TEST 8 8324 #define SQLITE_TESTCTRL_FAULT_INSTALL 9 8325 #define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10 8326 #define SQLITE_TESTCTRL_PENDING_BYTE 11 8327 #define SQLITE_TESTCTRL_ASSERT 12 8328 #define SQLITE_TESTCTRL_ALWAYS 13 8329 #define SQLITE_TESTCTRL_RESERVE 14 /* NOT USED */ 8330 #define SQLITE_TESTCTRL_JSON_SELFCHECK 14 8331 #define SQLITE_TESTCTRL_OPTIMIZATIONS 15 8332 #define SQLITE_TESTCTRL_ISKEYWORD 16 /* NOT USED */ 8333 #define SQLITE_TESTCTRL_SCRATCHMALLOC 17 /* NOT USED */ 8334 #define SQLITE_TESTCTRL_INTERNAL_FUNCTIONS 17 8335 #define SQLITE_TESTCTRL_LOCALTIME_FAULT 18 8336 #define SQLITE_TESTCTRL_EXPLAIN_STMT 19 /* NOT USED */ 8337 #define SQLITE_TESTCTRL_ONCE_RESET_THRESHOLD 19 8338 #define SQLITE_TESTCTRL_NEVER_CORRUPT 20 8339 #define SQLITE_TESTCTRL_VDBE_COVERAGE 21 8340 #define SQLITE_TESTCTRL_BYTEORDER 22 8341 #define SQLITE_TESTCTRL_ISINIT 23 8342 #define SQLITE_TESTCTRL_SORTER_MMAP 24 8343 #define SQLITE_TESTCTRL_IMPOSTER 25 8344 #define SQLITE_TESTCTRL_PARSER_COVERAGE 26 8345 #define SQLITE_TESTCTRL_RESULT_INTREAL 27 8346 #define SQLITE_TESTCTRL_PRNG_SEED 28 8347 #define SQLITE_TESTCTRL_EXTRA_SCHEMA_CHECKS 29 8348 #define SQLITE_TESTCTRL_SEEK_COUNT 30 8349 #define SQLITE_TESTCTRL_TRACEFLAGS 31 8350 #define SQLITE_TESTCTRL_TUNE 32 8351 #define SQLITE_TESTCTRL_LOGEST 33 8352 #define SQLITE_TESTCTRL_USELONGDOUBLE 34 8353 #define SQLITE_TESTCTRL_LAST 34 /* Largest TESTCTRL */ 8354 8355 /* 8356 ** CAPI3REF: SQL Keyword Checking 8357 ** 8358 ** These routines provide access to the set of SQL language keywords 8359 ** recognized by SQLite. Applications can uses these routines to determine 8360 ** whether or not a specific identifier needs to be escaped (for example, 8361 ** by enclosing in double-quotes) so as not to confuse the parser. 8362 ** 8363 ** The sqlite3_keyword_count() interface returns the number of distinct 8364 ** keywords understood by SQLite. 8365 ** 8366 ** The sqlite3_keyword_name(N,Z,L) interface finds the 0-based N-th keyword and 8367 ** makes *Z point to that keyword expressed as UTF8 and writes the number 8368 ** of bytes in the keyword into *L. The string that *Z points to is not 8369 ** zero-terminated. The sqlite3_keyword_name(N,Z,L) routine returns 8370 ** SQLITE_OK if N is within bounds and SQLITE_ERROR if not. If either Z 8371 ** or L are NULL or invalid pointers then calls to 8372 ** sqlite3_keyword_name(N,Z,L) result in undefined behavior. 8373 ** 8374 ** The sqlite3_keyword_check(Z,L) interface checks to see whether or not 8375 ** the L-byte UTF8 identifier that Z points to is a keyword, returning non-zero 8376 ** if it is and zero if not. 8377 ** 8378 ** The parser used by SQLite is forgiving. It is often possible to use 8379 ** a keyword as an identifier as long as such use does not result in a 8380 ** parsing ambiguity. For example, the statement 8381 ** "CREATE TABLE BEGIN(REPLACE,PRAGMA,END);" is accepted by SQLite, and 8382 ** creates a new table named "BEGIN" with three columns named 8383 ** "REPLACE", "PRAGMA", and "END". Nevertheless, best practice is to avoid 8384 ** using keywords as identifiers. Common techniques used to avoid keyword 8385 ** name collisions include: 8386 ** <ul> 8387 ** <li> Put all identifier names inside double-quotes. This is the official 8388 ** SQL way to escape identifier names. 8389 ** <li> Put identifier names inside [...]. This is not standard SQL, 8390 ** but it is what SQL Server does and so lots of programmers use this 8391 ** technique. 8392 ** <li> Begin every identifier with the letter "Z" as no SQL keywords start 8393 ** with "Z". 8394 ** <li> Include a digit somewhere in every identifier name. 8395 ** </ul> 8396 ** 8397 ** Note that the number of keywords understood by SQLite can depend on 8398 ** compile-time options. For example, "VACUUM" is not a keyword if 8399 ** SQLite is compiled with the [-DSQLITE_OMIT_VACUUM] option. Also, 8400 ** new keywords may be added to future releases of SQLite. 8401 */ 8402 SQLITE_API int sqlite3_keyword_count(void); 8403 SQLITE_API int sqlite3_keyword_name(int,const char**,int*); 8404 SQLITE_API int sqlite3_keyword_check(const char*,int); 8405 8406 /* 8407 ** CAPI3REF: Dynamic String Object 8408 ** KEYWORDS: {dynamic string} 8409 ** 8410 ** An instance of the sqlite3_str object contains a dynamically-sized 8411 ** string under construction. 8412 ** 8413 ** The lifecycle of an sqlite3_str object is as follows: 8414 ** <ol> 8415 ** <li> ^The sqlite3_str object is created using [sqlite3_str_new()]. 8416 ** <li> ^Text is appended to the sqlite3_str object using various 8417 ** methods, such as [sqlite3_str_appendf()]. 8418 ** <li> ^The sqlite3_str object is destroyed and the string it created 8419 ** is returned using the [sqlite3_str_finish()] interface. 8420 ** </ol> 8421 */ 8422 typedef struct sqlite3_str sqlite3_str; 8423 8424 /* 8425 ** CAPI3REF: Create A New Dynamic String Object 8426 ** CONSTRUCTOR: sqlite3_str 8427 ** 8428 ** ^The [sqlite3_str_new(D)] interface allocates and initializes 8429 ** a new [sqlite3_str] object. To avoid memory leaks, the object returned by 8430 ** [sqlite3_str_new()] must be freed by a subsequent call to 8431 ** [sqlite3_str_finish(X)]. 8432 ** 8433 ** ^The [sqlite3_str_new(D)] interface always returns a pointer to a 8434 ** valid [sqlite3_str] object, though in the event of an out-of-memory 8435 ** error the returned object might be a special singleton that will 8436 ** silently reject new text, always return SQLITE_NOMEM from 8437 ** [sqlite3_str_errcode()], always return 0 for 8438 ** [sqlite3_str_length()], and always return NULL from 8439 ** [sqlite3_str_finish(X)]. It is always safe to use the value 8440 ** returned by [sqlite3_str_new(D)] as the sqlite3_str parameter 8441 ** to any of the other [sqlite3_str] methods. 8442 ** 8443 ** The D parameter to [sqlite3_str_new(D)] may be NULL. If the 8444 ** D parameter in [sqlite3_str_new(D)] is not NULL, then the maximum 8445 ** length of the string contained in the [sqlite3_str] object will be 8446 ** the value set for [sqlite3_limit](D,[SQLITE_LIMIT_LENGTH]) instead 8447 ** of [SQLITE_MAX_LENGTH]. 8448 */ 8449 SQLITE_API sqlite3_str *sqlite3_str_new(sqlite3*); 8450 8451 /* 8452 ** CAPI3REF: Finalize A Dynamic String 8453 ** DESTRUCTOR: sqlite3_str 8454 ** 8455 ** ^The [sqlite3_str_finish(X)] interface destroys the sqlite3_str object X 8456 ** and returns a pointer to a memory buffer obtained from [sqlite3_malloc64()] 8457 ** that contains the constructed string. The calling application should 8458 ** pass the returned value to [sqlite3_free()] to avoid a memory leak. 8459 ** ^The [sqlite3_str_finish(X)] interface may return a NULL pointer if any 8460 ** errors were encountered during construction of the string. ^The 8461 ** [sqlite3_str_finish(X)] interface will also return a NULL pointer if the 8462 ** string in [sqlite3_str] object X is zero bytes long. 8463 */ 8464 SQLITE_API char *sqlite3_str_finish(sqlite3_str*); 8465 8466 /* 8467 ** CAPI3REF: Add Content To A Dynamic String 8468 ** METHOD: sqlite3_str 8469 ** 8470 ** These interfaces add content to an sqlite3_str object previously obtained 8471 ** from [sqlite3_str_new()]. 8472 ** 8473 ** ^The [sqlite3_str_appendf(X,F,...)] and 8474 ** [sqlite3_str_vappendf(X,F,V)] interfaces uses the [built-in printf] 8475 ** functionality of SQLite to append formatted text onto the end of 8476 ** [sqlite3_str] object X. 8477 ** 8478 ** ^The [sqlite3_str_append(X,S,N)] method appends exactly N bytes from string S 8479 ** onto the end of the [sqlite3_str] object X. N must be non-negative. 8480 ** S must contain at least N non-zero bytes of content. To append a 8481 ** zero-terminated string in its entirety, use the [sqlite3_str_appendall()] 8482 ** method instead. 8483 ** 8484 ** ^The [sqlite3_str_appendall(X,S)] method appends the complete content of 8485 ** zero-terminated string S onto the end of [sqlite3_str] object X. 8486 ** 8487 ** ^The [sqlite3_str_appendchar(X,N,C)] method appends N copies of the 8488 ** single-byte character C onto the end of [sqlite3_str] object X. 8489 ** ^This method can be used, for example, to add whitespace indentation. 8490 ** 8491 ** ^The [sqlite3_str_reset(X)] method resets the string under construction 8492 ** inside [sqlite3_str] object X back to zero bytes in length. 8493 ** 8494 ** These methods do not return a result code. ^If an error occurs, that fact 8495 ** is recorded in the [sqlite3_str] object and can be recovered by a 8496 ** subsequent call to [sqlite3_str_errcode(X)]. 8497 */ 8498 SQLITE_API void sqlite3_str_appendf(sqlite3_str*, const char *zFormat, ...); 8499 SQLITE_API void sqlite3_str_vappendf(sqlite3_str*, const char *zFormat, va_list); 8500 SQLITE_API void sqlite3_str_append(sqlite3_str*, const char *zIn, int N); 8501 SQLITE_API void sqlite3_str_appendall(sqlite3_str*, const char *zIn); 8502 SQLITE_API void sqlite3_str_appendchar(sqlite3_str*, int N, char C); 8503 SQLITE_API void sqlite3_str_reset(sqlite3_str*); 8504 8505 /* 8506 ** CAPI3REF: Status Of A Dynamic String 8507 ** METHOD: sqlite3_str 8508 ** 8509 ** These interfaces return the current status of an [sqlite3_str] object. 8510 ** 8511 ** ^If any prior errors have occurred while constructing the dynamic string 8512 ** in sqlite3_str X, then the [sqlite3_str_errcode(X)] method will return 8513 ** an appropriate error code. ^The [sqlite3_str_errcode(X)] method returns 8514 ** [SQLITE_NOMEM] following any out-of-memory error, or 8515 ** [SQLITE_TOOBIG] if the size of the dynamic string exceeds 8516 ** [SQLITE_MAX_LENGTH], or [SQLITE_OK] if there have been no errors. 8517 ** 8518 ** ^The [sqlite3_str_length(X)] method returns the current length, in bytes, 8519 ** of the dynamic string under construction in [sqlite3_str] object X. 8520 ** ^The length returned by [sqlite3_str_length(X)] does not include the 8521 ** zero-termination byte. 8522 ** 8523 ** ^The [sqlite3_str_value(X)] method returns a pointer to the current 8524 ** content of the dynamic string under construction in X. The value 8525 ** returned by [sqlite3_str_value(X)] is managed by the sqlite3_str object X 8526 ** and might be freed or altered by any subsequent method on the same 8527 ** [sqlite3_str] object. Applications must not used the pointer returned 8528 ** [sqlite3_str_value(X)] after any subsequent method call on the same 8529 ** object. ^Applications may change the content of the string returned 8530 ** by [sqlite3_str_value(X)] as long as they do not write into any bytes 8531 ** outside the range of 0 to [sqlite3_str_length(X)] and do not read or 8532 ** write any byte after any subsequent sqlite3_str method call. 8533 */ 8534 SQLITE_API int sqlite3_str_errcode(sqlite3_str*); 8535 SQLITE_API int sqlite3_str_length(sqlite3_str*); 8536 SQLITE_API char *sqlite3_str_value(sqlite3_str*); 8537 8538 /* 8539 ** CAPI3REF: SQLite Runtime Status 8540 ** 8541 ** ^These interfaces are used to retrieve runtime status information 8542 ** about the performance of SQLite, and optionally to reset various 8543 ** highwater marks. ^The first argument is an integer code for 8544 ** the specific parameter to measure. ^(Recognized integer codes 8545 ** are of the form [status parameters | SQLITE_STATUS_...].)^ 8546 ** ^The current value of the parameter is returned into *pCurrent. 8547 ** ^The highest recorded value is returned in *pHighwater. ^If the 8548 ** resetFlag is true, then the highest record value is reset after 8549 ** *pHighwater is written. ^(Some parameters do not record the highest 8550 ** value. For those parameters 8551 ** nothing is written into *pHighwater and the resetFlag is ignored.)^ 8552 ** ^(Other parameters record only the highwater mark and not the current 8553 ** value. For these latter parameters nothing is written into *pCurrent.)^ 8554 ** 8555 ** ^The sqlite3_status() and sqlite3_status64() routines return 8556 ** SQLITE_OK on success and a non-zero [error code] on failure. 8557 ** 8558 ** If either the current value or the highwater mark is too large to 8559 ** be represented by a 32-bit integer, then the values returned by 8560 ** sqlite3_status() are undefined. 8561 ** 8562 ** See also: [sqlite3_db_status()] 8563 */ 8564 SQLITE_API int sqlite3_status(int op, int *pCurrent, int *pHighwater, int resetFlag); 8565 SQLITE_API int sqlite3_status64( 8566 int op, 8567 sqlite3_int64 *pCurrent, 8568 sqlite3_int64 *pHighwater, 8569 int resetFlag 8570 ); 8571 8572 8573 /* 8574 ** CAPI3REF: Status Parameters 8575 ** KEYWORDS: {status parameters} 8576 ** 8577 ** These integer constants designate various run-time status parameters 8578 ** that can be returned by [sqlite3_status()]. 8579 ** 8580 ** <dl> 8581 ** [[SQLITE_STATUS_MEMORY_USED]] ^(<dt>SQLITE_STATUS_MEMORY_USED</dt> 8582 ** <dd>This parameter is the current amount of memory checked out 8583 ** using [sqlite3_malloc()], either directly or indirectly. The 8584 ** figure includes calls made to [sqlite3_malloc()] by the application 8585 ** and internal memory usage by the SQLite library. Auxiliary page-cache 8586 ** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in 8587 ** this parameter. The amount returned is the sum of the allocation 8588 ** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^ 8589 ** 8590 ** [[SQLITE_STATUS_MALLOC_SIZE]] ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt> 8591 ** <dd>This parameter records the largest memory allocation request 8592 ** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their 8593 ** internal equivalents). Only the value returned in the 8594 ** *pHighwater parameter to [sqlite3_status()] is of interest. 8595 ** The value written into the *pCurrent parameter is undefined.</dd>)^ 8596 ** 8597 ** [[SQLITE_STATUS_MALLOC_COUNT]] ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt> 8598 ** <dd>This parameter records the number of separate memory allocations 8599 ** currently checked out.</dd>)^ 8600 ** 8601 ** [[SQLITE_STATUS_PAGECACHE_USED]] ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt> 8602 ** <dd>This parameter returns the number of pages used out of the 8603 ** [pagecache memory allocator] that was configured using 8604 ** [SQLITE_CONFIG_PAGECACHE]. The 8605 ** value returned is in pages, not in bytes.</dd>)^ 8606 ** 8607 ** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]] 8608 ** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt> 8609 ** <dd>This parameter returns the number of bytes of page cache 8610 ** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE] 8611 ** buffer and where forced to overflow to [sqlite3_malloc()]. The 8612 ** returned value includes allocations that overflowed because they 8613 ** where too large (they were larger than the "sz" parameter to 8614 ** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because 8615 ** no space was left in the page cache.</dd>)^ 8616 ** 8617 ** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt> 8618 ** <dd>This parameter records the largest memory allocation request 8619 ** handed to the [pagecache memory allocator]. Only the value returned in the 8620 ** *pHighwater parameter to [sqlite3_status()] is of interest. 8621 ** The value written into the *pCurrent parameter is undefined.</dd>)^ 8622 ** 8623 ** [[SQLITE_STATUS_SCRATCH_USED]] <dt>SQLITE_STATUS_SCRATCH_USED</dt> 8624 ** <dd>No longer used.</dd> 8625 ** 8626 ** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt> 8627 ** <dd>No longer used.</dd> 8628 ** 8629 ** [[SQLITE_STATUS_SCRATCH_SIZE]] <dt>SQLITE_STATUS_SCRATCH_SIZE</dt> 8630 ** <dd>No longer used.</dd> 8631 ** 8632 ** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt> 8633 ** <dd>The *pHighwater parameter records the deepest parser stack. 8634 ** The *pCurrent value is undefined. The *pHighwater value is only 8635 ** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^ 8636 ** </dl> 8637 ** 8638 ** New status parameters may be added from time to time. 8639 */ 8640 #define SQLITE_STATUS_MEMORY_USED 0 8641 #define SQLITE_STATUS_PAGECACHE_USED 1 8642 #define SQLITE_STATUS_PAGECACHE_OVERFLOW 2 8643 #define SQLITE_STATUS_SCRATCH_USED 3 /* NOT USED */ 8644 #define SQLITE_STATUS_SCRATCH_OVERFLOW 4 /* NOT USED */ 8645 #define SQLITE_STATUS_MALLOC_SIZE 5 8646 #define SQLITE_STATUS_PARSER_STACK 6 8647 #define SQLITE_STATUS_PAGECACHE_SIZE 7 8648 #define SQLITE_STATUS_SCRATCH_SIZE 8 /* NOT USED */ 8649 #define SQLITE_STATUS_MALLOC_COUNT 9 8650 8651 /* 8652 ** CAPI3REF: Database Connection Status 8653 ** METHOD: sqlite3 8654 ** 8655 ** ^This interface is used to retrieve runtime status information 8656 ** about a single [database connection]. ^The first argument is the 8657 ** database connection object to be interrogated. ^The second argument 8658 ** is an integer constant, taken from the set of 8659 ** [SQLITE_DBSTATUS options], that 8660 ** determines the parameter to interrogate. The set of 8661 ** [SQLITE_DBSTATUS options] is likely 8662 ** to grow in future releases of SQLite. 8663 ** 8664 ** ^The current value of the requested parameter is written into *pCur 8665 ** and the highest instantaneous value is written into *pHiwtr. ^If 8666 ** the resetFlg is true, then the highest instantaneous value is 8667 ** reset back down to the current value. 8668 ** 8669 ** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a 8670 ** non-zero [error code] on failure. 8671 ** 8672 ** See also: [sqlite3_status()] and [sqlite3_stmt_status()]. 8673 */ 8674 SQLITE_API int sqlite3_db_status(sqlite3*, int op, int *pCur, int *pHiwtr, int resetFlg); 8675 8676 /* 8677 ** CAPI3REF: Status Parameters for database connections 8678 ** KEYWORDS: {SQLITE_DBSTATUS options} 8679 ** 8680 ** These constants are the available integer "verbs" that can be passed as 8681 ** the second argument to the [sqlite3_db_status()] interface. 8682 ** 8683 ** New verbs may be added in future releases of SQLite. Existing verbs 8684 ** might be discontinued. Applications should check the return code from 8685 ** [sqlite3_db_status()] to make sure that the call worked. 8686 ** The [sqlite3_db_status()] interface will return a non-zero error code 8687 ** if a discontinued or unsupported verb is invoked. 8688 ** 8689 ** <dl> 8690 ** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt> 8691 ** <dd>This parameter returns the number of lookaside memory slots currently 8692 ** checked out.</dd>)^ 8693 ** 8694 ** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_HIT</dt> 8695 ** <dd>This parameter returns the number of malloc attempts that were 8696 ** satisfied using lookaside memory. Only the high-water value is meaningful; 8697 ** the current value is always zero.)^ 8698 ** 8699 ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]] 8700 ** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE</dt> 8701 ** <dd>This parameter returns the number malloc attempts that might have 8702 ** been satisfied using lookaside memory but failed due to the amount of 8703 ** memory requested being larger than the lookaside slot size. 8704 ** Only the high-water value is meaningful; 8705 ** the current value is always zero.)^ 8706 ** 8707 ** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]] 8708 ** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL</dt> 8709 ** <dd>This parameter returns the number malloc attempts that might have 8710 ** been satisfied using lookaside memory but failed due to all lookaside 8711 ** memory already being in use. 8712 ** Only the high-water value is meaningful; 8713 ** the current value is always zero.)^ 8714 ** 8715 ** [[SQLITE_DBSTATUS_CACHE_USED]] ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt> 8716 ** <dd>This parameter returns the approximate number of bytes of heap 8717 ** memory used by all pager caches associated with the database connection.)^ 8718 ** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0. 8719 ** 8720 ** [[SQLITE_DBSTATUS_CACHE_USED_SHARED]] 8721 ** ^(<dt>SQLITE_DBSTATUS_CACHE_USED_SHARED</dt> 8722 ** <dd>This parameter is similar to DBSTATUS_CACHE_USED, except that if a 8723 ** pager cache is shared between two or more connections the bytes of heap 8724 ** memory used by that pager cache is divided evenly between the attached 8725 ** connections.)^ In other words, if none of the pager caches associated 8726 ** with the database connection are shared, this request returns the same 8727 ** value as DBSTATUS_CACHE_USED. Or, if one or more or the pager caches are 8728 ** shared, the value returned by this call will be smaller than that returned 8729 ** by DBSTATUS_CACHE_USED. ^The highwater mark associated with 8730 ** SQLITE_DBSTATUS_CACHE_USED_SHARED is always 0. 8731 ** 8732 ** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt> 8733 ** <dd>This parameter returns the approximate number of bytes of heap 8734 ** memory used to store the schema for all databases associated 8735 ** with the connection - main, temp, and any [ATTACH]-ed databases.)^ 8736 ** ^The full amount of memory used by the schemas is reported, even if the 8737 ** schema memory is shared with other database connections due to 8738 ** [shared cache mode] being enabled. 8739 ** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0. 8740 ** 8741 ** [[SQLITE_DBSTATUS_STMT_USED]] ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt> 8742 ** <dd>This parameter returns the approximate number of bytes of heap 8743 ** and lookaside memory used by all prepared statements associated with 8744 ** the database connection.)^ 8745 ** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0. 8746 ** </dd> 8747 ** 8748 ** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(<dt>SQLITE_DBSTATUS_CACHE_HIT</dt> 8749 ** <dd>This parameter returns the number of pager cache hits that have 8750 ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT 8751 ** is always 0. 8752 ** </dd> 8753 ** 8754 ** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(<dt>SQLITE_DBSTATUS_CACHE_MISS</dt> 8755 ** <dd>This parameter returns the number of pager cache misses that have 8756 ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS 8757 ** is always 0. 8758 ** </dd> 8759 ** 8760 ** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(<dt>SQLITE_DBSTATUS_CACHE_WRITE</dt> 8761 ** <dd>This parameter returns the number of dirty cache entries that have 8762 ** been written to disk. Specifically, the number of pages written to the 8763 ** wal file in wal mode databases, or the number of pages written to the 8764 ** database file in rollback mode databases. Any pages written as part of 8765 ** transaction rollback or database recovery operations are not included. 8766 ** If an IO or other error occurs while writing a page to disk, the effect 8767 ** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The 8768 ** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0. 8769 ** </dd> 8770 ** 8771 ** [[SQLITE_DBSTATUS_CACHE_SPILL]] ^(<dt>SQLITE_DBSTATUS_CACHE_SPILL</dt> 8772 ** <dd>This parameter returns the number of dirty cache entries that have 8773 ** been written to disk in the middle of a transaction due to the page 8774 ** cache overflowing. Transactions are more efficient if they are written 8775 ** to disk all at once. When pages spill mid-transaction, that introduces 8776 ** additional overhead. This parameter can be used help identify 8777 ** inefficiencies that can be resolved by increasing the cache size. 8778 ** </dd> 8779 ** 8780 ** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(<dt>SQLITE_DBSTATUS_DEFERRED_FKS</dt> 8781 ** <dd>This parameter returns zero for the current value if and only if 8782 ** all foreign key constraints (deferred or immediate) have been 8783 ** resolved.)^ ^The highwater mark is always 0. 8784 ** </dd> 8785 ** </dl> 8786 */ 8787 #define SQLITE_DBSTATUS_LOOKASIDE_USED 0 8788 #define SQLITE_DBSTATUS_CACHE_USED 1 8789 #define SQLITE_DBSTATUS_SCHEMA_USED 2 8790 #define SQLITE_DBSTATUS_STMT_USED 3 8791 #define SQLITE_DBSTATUS_LOOKASIDE_HIT 4 8792 #define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE 5 8793 #define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL 6 8794 #define SQLITE_DBSTATUS_CACHE_HIT 7 8795 #define SQLITE_DBSTATUS_CACHE_MISS 8 8796 #define SQLITE_DBSTATUS_CACHE_WRITE 9 8797 #define SQLITE_DBSTATUS_DEFERRED_FKS 10 8798 #define SQLITE_DBSTATUS_CACHE_USED_SHARED 11 8799 #define SQLITE_DBSTATUS_CACHE_SPILL 12 8800 #define SQLITE_DBSTATUS_MAX 12 /* Largest defined DBSTATUS */ 8801 8802 8803 /* 8804 ** CAPI3REF: Prepared Statement Status 8805 ** METHOD: sqlite3_stmt 8806 ** 8807 ** ^(Each prepared statement maintains various 8808 ** [SQLITE_STMTSTATUS counters] that measure the number 8809 ** of times it has performed specific operations.)^ These counters can 8810 ** be used to monitor the performance characteristics of the prepared 8811 ** statements. For example, if the number of table steps greatly exceeds 8812 ** the number of table searches or result rows, that would tend to indicate 8813 ** that the prepared statement is using a full table scan rather than 8814 ** an index. 8815 ** 8816 ** ^(This interface is used to retrieve and reset counter values from 8817 ** a [prepared statement]. The first argument is the prepared statement 8818 ** object to be interrogated. The second argument 8819 ** is an integer code for a specific [SQLITE_STMTSTATUS counter] 8820 ** to be interrogated.)^ 8821 ** ^The current value of the requested counter is returned. 8822 ** ^If the resetFlg is true, then the counter is reset to zero after this 8823 ** interface call returns. 8824 ** 8825 ** See also: [sqlite3_status()] and [sqlite3_db_status()]. 8826 */ 8827 SQLITE_API int sqlite3_stmt_status(sqlite3_stmt*, int op,int resetFlg); 8828 8829 /* 8830 ** CAPI3REF: Status Parameters for prepared statements 8831 ** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters} 8832 ** 8833 ** These preprocessor macros define integer codes that name counter 8834 ** values associated with the [sqlite3_stmt_status()] interface. 8835 ** The meanings of the various counters are as follows: 8836 ** 8837 ** <dl> 8838 ** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt> 8839 ** <dd>^This is the number of times that SQLite has stepped forward in 8840 ** a table as part of a full table scan. Large numbers for this counter 8841 ** may indicate opportunities for performance improvement through 8842 ** careful use of indices.</dd> 8843 ** 8844 ** [[SQLITE_STMTSTATUS_SORT]] <dt>SQLITE_STMTSTATUS_SORT</dt> 8845 ** <dd>^This is the number of sort operations that have occurred. 8846 ** A non-zero value in this counter may indicate an opportunity to 8847 ** improvement performance through careful use of indices.</dd> 8848 ** 8849 ** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt> 8850 ** <dd>^This is the number of rows inserted into transient indices that 8851 ** were created automatically in order to help joins run faster. 8852 ** A non-zero value in this counter may indicate an opportunity to 8853 ** improvement performance by adding permanent indices that do not 8854 ** need to be reinitialized each time the statement is run.</dd> 8855 ** 8856 ** [[SQLITE_STMTSTATUS_VM_STEP]] <dt>SQLITE_STMTSTATUS_VM_STEP</dt> 8857 ** <dd>^This is the number of virtual machine operations executed 8858 ** by the prepared statement if that number is less than or equal 8859 ** to 2147483647. The number of virtual machine operations can be 8860 ** used as a proxy for the total work done by the prepared statement. 8861 ** If the number of virtual machine operations exceeds 2147483647 8862 ** then the value returned by this statement status code is undefined. 8863 ** 8864 ** [[SQLITE_STMTSTATUS_REPREPARE]] <dt>SQLITE_STMTSTATUS_REPREPARE</dt> 8865 ** <dd>^This is the number of times that the prepare statement has been 8866 ** automatically regenerated due to schema changes or changes to 8867 ** [bound parameters] that might affect the query plan. 8868 ** 8869 ** [[SQLITE_STMTSTATUS_RUN]] <dt>SQLITE_STMTSTATUS_RUN</dt> 8870 ** <dd>^This is the number of times that the prepared statement has 8871 ** been run. A single "run" for the purposes of this counter is one 8872 ** or more calls to [sqlite3_step()] followed by a call to [sqlite3_reset()]. 8873 ** The counter is incremented on the first [sqlite3_step()] call of each 8874 ** cycle. 8875 ** 8876 ** [[SQLITE_STMTSTATUS_FILTER_MISS]] 8877 ** [[SQLITE_STMTSTATUS_FILTER HIT]] 8878 ** <dt>SQLITE_STMTSTATUS_FILTER_HIT<br> 8879 ** SQLITE_STMTSTATUS_FILTER_MISS</dt> 8880 ** <dd>^SQLITE_STMTSTATUS_FILTER_HIT is the number of times that a join 8881 ** step was bypassed because a Bloom filter returned not-found. The 8882 ** corresponding SQLITE_STMTSTATUS_FILTER_MISS value is the number of 8883 ** times that the Bloom filter returned a find, and thus the join step 8884 ** had to be processed as normal. 8885 ** 8886 ** [[SQLITE_STMTSTATUS_MEMUSED]] <dt>SQLITE_STMTSTATUS_MEMUSED</dt> 8887 ** <dd>^This is the approximate number of bytes of heap memory 8888 ** used to store the prepared statement. ^This value is not actually 8889 ** a counter, and so the resetFlg parameter to sqlite3_stmt_status() 8890 ** is ignored when the opcode is SQLITE_STMTSTATUS_MEMUSED. 8891 ** </dd> 8892 ** </dl> 8893 */ 8894 #define SQLITE_STMTSTATUS_FULLSCAN_STEP 1 8895 #define SQLITE_STMTSTATUS_SORT 2 8896 #define SQLITE_STMTSTATUS_AUTOINDEX 3 8897 #define SQLITE_STMTSTATUS_VM_STEP 4 8898 #define SQLITE_STMTSTATUS_REPREPARE 5 8899 #define SQLITE_STMTSTATUS_RUN 6 8900 #define SQLITE_STMTSTATUS_FILTER_MISS 7 8901 #define SQLITE_STMTSTATUS_FILTER_HIT 8 8902 #define SQLITE_STMTSTATUS_MEMUSED 99 8903 8904 /* 8905 ** CAPI3REF: Custom Page Cache Object 8906 ** 8907 ** The sqlite3_pcache type is opaque. It is implemented by 8908 ** the pluggable module. The SQLite core has no knowledge of 8909 ** its size or internal structure and never deals with the 8910 ** sqlite3_pcache object except by holding and passing pointers 8911 ** to the object. 8912 ** 8913 ** See [sqlite3_pcache_methods2] for additional information. 8914 */ 8915 typedef struct sqlite3_pcache sqlite3_pcache; 8916 8917 /* 8918 ** CAPI3REF: Custom Page Cache Object 8919 ** 8920 ** The sqlite3_pcache_page object represents a single page in the 8921 ** page cache. The page cache will allocate instances of this 8922 ** object. Various methods of the page cache use pointers to instances 8923 ** of this object as parameters or as their return value. 8924 ** 8925 ** See [sqlite3_pcache_methods2] for additional information. 8926 */ 8927 typedef struct sqlite3_pcache_page sqlite3_pcache_page; 8928 struct sqlite3_pcache_page { 8929 void *pBuf; /* The content of the page */ 8930 void *pExtra; /* Extra information associated with the page */ 8931 }; 8932 8933 /* 8934 ** CAPI3REF: Application Defined Page Cache. 8935 ** KEYWORDS: {page cache} 8936 ** 8937 ** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can 8938 ** register an alternative page cache implementation by passing in an 8939 ** instance of the sqlite3_pcache_methods2 structure.)^ 8940 ** In many applications, most of the heap memory allocated by 8941 ** SQLite is used for the page cache. 8942 ** By implementing a 8943 ** custom page cache using this API, an application can better control 8944 ** the amount of memory consumed by SQLite, the way in which 8945 ** that memory is allocated and released, and the policies used to 8946 ** determine exactly which parts of a database file are cached and for 8947 ** how long. 8948 ** 8949 ** The alternative page cache mechanism is an 8950 ** extreme measure that is only needed by the most demanding applications. 8951 ** The built-in page cache is recommended for most uses. 8952 ** 8953 ** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an 8954 ** internal buffer by SQLite within the call to [sqlite3_config]. Hence 8955 ** the application may discard the parameter after the call to 8956 ** [sqlite3_config()] returns.)^ 8957 ** 8958 ** [[the xInit() page cache method]] 8959 ** ^(The xInit() method is called once for each effective 8960 ** call to [sqlite3_initialize()])^ 8961 ** (usually only once during the lifetime of the process). ^(The xInit() 8962 ** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^ 8963 ** The intent of the xInit() method is to set up global data structures 8964 ** required by the custom page cache implementation. 8965 ** ^(If the xInit() method is NULL, then the 8966 ** built-in default page cache is used instead of the application defined 8967 ** page cache.)^ 8968 ** 8969 ** [[the xShutdown() page cache method]] 8970 ** ^The xShutdown() method is called by [sqlite3_shutdown()]. 8971 ** It can be used to clean up 8972 ** any outstanding resources before process shutdown, if required. 8973 ** ^The xShutdown() method may be NULL. 8974 ** 8975 ** ^SQLite automatically serializes calls to the xInit method, 8976 ** so the xInit method need not be threadsafe. ^The 8977 ** xShutdown method is only called from [sqlite3_shutdown()] so it does 8978 ** not need to be threadsafe either. All other methods must be threadsafe 8979 ** in multithreaded applications. 8980 ** 8981 ** ^SQLite will never invoke xInit() more than once without an intervening 8982 ** call to xShutdown(). 8983 ** 8984 ** [[the xCreate() page cache methods]] 8985 ** ^SQLite invokes the xCreate() method to construct a new cache instance. 8986 ** SQLite will typically create one cache instance for each open database file, 8987 ** though this is not guaranteed. ^The 8988 ** first parameter, szPage, is the size in bytes of the pages that must 8989 ** be allocated by the cache. ^szPage will always a power of two. ^The 8990 ** second parameter szExtra is a number of bytes of extra storage 8991 ** associated with each page cache entry. ^The szExtra parameter will 8992 ** a number less than 250. SQLite will use the 8993 ** extra szExtra bytes on each page to store metadata about the underlying 8994 ** database page on disk. The value passed into szExtra depends 8995 ** on the SQLite version, the target platform, and how SQLite was compiled. 8996 ** ^The third argument to xCreate(), bPurgeable, is true if the cache being 8997 ** created will be used to cache database pages of a file stored on disk, or 8998 ** false if it is used for an in-memory database. The cache implementation 8999 ** does not have to do anything special based with the value of bPurgeable; 9000 ** it is purely advisory. ^On a cache where bPurgeable is false, SQLite will 9001 ** never invoke xUnpin() except to deliberately delete a page. 9002 ** ^In other words, calls to xUnpin() on a cache with bPurgeable set to 9003 ** false will always have the "discard" flag set to true. 9004 ** ^Hence, a cache created with bPurgeable false will 9005 ** never contain any unpinned pages. 9006 ** 9007 ** [[the xCachesize() page cache method]] 9008 ** ^(The xCachesize() method may be called at any time by SQLite to set the 9009 ** suggested maximum cache-size (number of pages stored by) the cache 9010 ** instance passed as the first argument. This is the value configured using 9011 ** the SQLite "[PRAGMA cache_size]" command.)^ As with the bPurgeable 9012 ** parameter, the implementation is not required to do anything with this 9013 ** value; it is advisory only. 9014 ** 9015 ** [[the xPagecount() page cache methods]] 9016 ** The xPagecount() method must return the number of pages currently 9017 ** stored in the cache, both pinned and unpinned. 9018 ** 9019 ** [[the xFetch() page cache methods]] 9020 ** The xFetch() method locates a page in the cache and returns a pointer to 9021 ** an sqlite3_pcache_page object associated with that page, or a NULL pointer. 9022 ** The pBuf element of the returned sqlite3_pcache_page object will be a 9023 ** pointer to a buffer of szPage bytes used to store the content of a 9024 ** single database page. The pExtra element of sqlite3_pcache_page will be 9025 ** a pointer to the szExtra bytes of extra storage that SQLite has requested 9026 ** for each entry in the page cache. 9027 ** 9028 ** The page to be fetched is determined by the key. ^The minimum key value 9029 ** is 1. After it has been retrieved using xFetch, the page is considered 9030 ** to be "pinned". 9031 ** 9032 ** If the requested page is already in the page cache, then the page cache 9033 ** implementation must return a pointer to the page buffer with its content 9034 ** intact. If the requested page is not already in the cache, then the 9035 ** cache implementation should use the value of the createFlag 9036 ** parameter to help it determined what action to take: 9037 ** 9038 ** <table border=1 width=85% align=center> 9039 ** <tr><th> createFlag <th> Behavior when page is not already in cache 9040 ** <tr><td> 0 <td> Do not allocate a new page. Return NULL. 9041 ** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so. 9042 ** Otherwise return NULL. 9043 ** <tr><td> 2 <td> Make every effort to allocate a new page. Only return 9044 ** NULL if allocating a new page is effectively impossible. 9045 ** </table> 9046 ** 9047 ** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1. SQLite 9048 ** will only use a createFlag of 2 after a prior call with a createFlag of 1 9049 ** failed.)^ In between the xFetch() calls, SQLite may 9050 ** attempt to unpin one or more cache pages by spilling the content of 9051 ** pinned pages to disk and synching the operating system disk cache. 9052 ** 9053 ** [[the xUnpin() page cache method]] 9054 ** ^xUnpin() is called by SQLite with a pointer to a currently pinned page 9055 ** as its second argument. If the third parameter, discard, is non-zero, 9056 ** then the page must be evicted from the cache. 9057 ** ^If the discard parameter is 9058 ** zero, then the page may be discarded or retained at the discretion of 9059 ** page cache implementation. ^The page cache implementation 9060 ** may choose to evict unpinned pages at any time. 9061 ** 9062 ** The cache must not perform any reference counting. A single 9063 ** call to xUnpin() unpins the page regardless of the number of prior calls 9064 ** to xFetch(). 9065 ** 9066 ** [[the xRekey() page cache methods]] 9067 ** The xRekey() method is used to change the key value associated with the 9068 ** page passed as the second argument. If the cache 9069 ** previously contains an entry associated with newKey, it must be 9070 ** discarded. ^Any prior cache entry associated with newKey is guaranteed not 9071 ** to be pinned. 9072 ** 9073 ** When SQLite calls the xTruncate() method, the cache must discard all 9074 ** existing cache entries with page numbers (keys) greater than or equal 9075 ** to the value of the iLimit parameter passed to xTruncate(). If any 9076 ** of these pages are pinned, they are implicitly unpinned, meaning that 9077 ** they can be safely discarded. 9078 ** 9079 ** [[the xDestroy() page cache method]] 9080 ** ^The xDestroy() method is used to delete a cache allocated by xCreate(). 9081 ** All resources associated with the specified cache should be freed. ^After 9082 ** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*] 9083 ** handle invalid, and will not use it with any other sqlite3_pcache_methods2 9084 ** functions. 9085 ** 9086 ** [[the xShrink() page cache method]] 9087 ** ^SQLite invokes the xShrink() method when it wants the page cache to 9088 ** free up as much of heap memory as possible. The page cache implementation 9089 ** is not obligated to free any memory, but well-behaved implementations should 9090 ** do their best. 9091 */ 9092 typedef struct sqlite3_pcache_methods2 sqlite3_pcache_methods2; 9093 struct sqlite3_pcache_methods2 { 9094 int iVersion; 9095 void *pArg; 9096 int (*xInit)(void*); 9097 void (*xShutdown)(void*); 9098 sqlite3_pcache *(*xCreate)(int szPage, int szExtra, int bPurgeable); 9099 void (*xCachesize)(sqlite3_pcache*, int nCachesize); 9100 int (*xPagecount)(sqlite3_pcache*); 9101 sqlite3_pcache_page *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag); 9102 void (*xUnpin)(sqlite3_pcache*, sqlite3_pcache_page*, int discard); 9103 void (*xRekey)(sqlite3_pcache*, sqlite3_pcache_page*, 9104 unsigned oldKey, unsigned newKey); 9105 void (*xTruncate)(sqlite3_pcache*, unsigned iLimit); 9106 void (*xDestroy)(sqlite3_pcache*); 9107 void (*xShrink)(sqlite3_pcache*); 9108 }; 9109 9110 /* 9111 ** This is the obsolete pcache_methods object that has now been replaced 9112 ** by sqlite3_pcache_methods2. This object is not used by SQLite. It is 9113 ** retained in the header file for backwards compatibility only. 9114 */ 9115 typedef struct sqlite3_pcache_methods sqlite3_pcache_methods; 9116 struct sqlite3_pcache_methods { 9117 void *pArg; 9118 int (*xInit)(void*); 9119 void (*xShutdown)(void*); 9120 sqlite3_pcache *(*xCreate)(int szPage, int bPurgeable); 9121 void (*xCachesize)(sqlite3_pcache*, int nCachesize); 9122 int (*xPagecount)(sqlite3_pcache*); 9123 void *(*xFetch)(sqlite3_pcache*, unsigned key, int createFlag); 9124 void (*xUnpin)(sqlite3_pcache*, void*, int discard); 9125 void (*xRekey)(sqlite3_pcache*, void*, unsigned oldKey, unsigned newKey); 9126 void (*xTruncate)(sqlite3_pcache*, unsigned iLimit); 9127 void (*xDestroy)(sqlite3_pcache*); 9128 }; 9129 9130 9131 /* 9132 ** CAPI3REF: Online Backup Object 9133 ** 9134 ** The sqlite3_backup object records state information about an ongoing 9135 ** online backup operation. ^The sqlite3_backup object is created by 9136 ** a call to [sqlite3_backup_init()] and is destroyed by a call to 9137 ** [sqlite3_backup_finish()]. 9138 ** 9139 ** See Also: [Using the SQLite Online Backup API] 9140 */ 9141 typedef struct sqlite3_backup sqlite3_backup; 9142 9143 /* 9144 ** CAPI3REF: Online Backup API. 9145 ** 9146 ** The backup API copies the content of one database into another. 9147 ** It is useful either for creating backups of databases or 9148 ** for copying in-memory databases to or from persistent files. 9149 ** 9150 ** See Also: [Using the SQLite Online Backup API] 9151 ** 9152 ** ^SQLite holds a write transaction open on the destination database file 9153 ** for the duration of the backup operation. 9154 ** ^The source database is read-locked only while it is being read; 9155 ** it is not locked continuously for the entire backup operation. 9156 ** ^Thus, the backup may be performed on a live source database without 9157 ** preventing other database connections from 9158 ** reading or writing to the source database while the backup is underway. 9159 ** 9160 ** ^(To perform a backup operation: 9161 ** <ol> 9162 ** <li><b>sqlite3_backup_init()</b> is called once to initialize the 9163 ** backup, 9164 ** <li><b>sqlite3_backup_step()</b> is called one or more times to transfer 9165 ** the data between the two databases, and finally 9166 ** <li><b>sqlite3_backup_finish()</b> is called to release all resources 9167 ** associated with the backup operation. 9168 ** </ol>)^ 9169 ** There should be exactly one call to sqlite3_backup_finish() for each 9170 ** successful call to sqlite3_backup_init(). 9171 ** 9172 ** [[sqlite3_backup_init()]] <b>sqlite3_backup_init()</b> 9173 ** 9174 ** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the 9175 ** [database connection] associated with the destination database 9176 ** and the database name, respectively. 9177 ** ^The database name is "main" for the main database, "temp" for the 9178 ** temporary database, or the name specified after the AS keyword in 9179 ** an [ATTACH] statement for an attached database. 9180 ** ^The S and M arguments passed to 9181 ** sqlite3_backup_init(D,N,S,M) identify the [database connection] 9182 ** and database name of the source database, respectively. 9183 ** ^The source and destination [database connections] (parameters S and D) 9184 ** must be different or else sqlite3_backup_init(D,N,S,M) will fail with 9185 ** an error. 9186 ** 9187 ** ^A call to sqlite3_backup_init() will fail, returning NULL, if 9188 ** there is already a read or read-write transaction open on the 9189 ** destination database. 9190 ** 9191 ** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is 9192 ** returned and an error code and error message are stored in the 9193 ** destination [database connection] D. 9194 ** ^The error code and message for the failed call to sqlite3_backup_init() 9195 ** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or 9196 ** [sqlite3_errmsg16()] functions. 9197 ** ^A successful call to sqlite3_backup_init() returns a pointer to an 9198 ** [sqlite3_backup] object. 9199 ** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and 9200 ** sqlite3_backup_finish() functions to perform the specified backup 9201 ** operation. 9202 ** 9203 ** [[sqlite3_backup_step()]] <b>sqlite3_backup_step()</b> 9204 ** 9205 ** ^Function sqlite3_backup_step(B,N) will copy up to N pages between 9206 ** the source and destination databases specified by [sqlite3_backup] object B. 9207 ** ^If N is negative, all remaining source pages are copied. 9208 ** ^If sqlite3_backup_step(B,N) successfully copies N pages and there 9209 ** are still more pages to be copied, then the function returns [SQLITE_OK]. 9210 ** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages 9211 ** from source to destination, then it returns [SQLITE_DONE]. 9212 ** ^If an error occurs while running sqlite3_backup_step(B,N), 9213 ** then an [error code] is returned. ^As well as [SQLITE_OK] and 9214 ** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY], 9215 ** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an 9216 ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code. 9217 ** 9218 ** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if 9219 ** <ol> 9220 ** <li> the destination database was opened read-only, or 9221 ** <li> the destination database is using write-ahead-log journaling 9222 ** and the destination and source page sizes differ, or 9223 ** <li> the destination database is an in-memory database and the 9224 ** destination and source page sizes differ. 9225 ** </ol>)^ 9226 ** 9227 ** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then 9228 ** the [sqlite3_busy_handler | busy-handler function] 9229 ** is invoked (if one is specified). ^If the 9230 ** busy-handler returns non-zero before the lock is available, then 9231 ** [SQLITE_BUSY] is returned to the caller. ^In this case the call to 9232 ** sqlite3_backup_step() can be retried later. ^If the source 9233 ** [database connection] 9234 ** is being used to write to the source database when sqlite3_backup_step() 9235 ** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this 9236 ** case the call to sqlite3_backup_step() can be retried later on. ^(If 9237 ** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or 9238 ** [SQLITE_READONLY] is returned, then 9239 ** there is no point in retrying the call to sqlite3_backup_step(). These 9240 ** errors are considered fatal.)^ The application must accept 9241 ** that the backup operation has failed and pass the backup operation handle 9242 ** to the sqlite3_backup_finish() to release associated resources. 9243 ** 9244 ** ^The first call to sqlite3_backup_step() obtains an exclusive lock 9245 ** on the destination file. ^The exclusive lock is not released until either 9246 ** sqlite3_backup_finish() is called or the backup operation is complete 9247 ** and sqlite3_backup_step() returns [SQLITE_DONE]. ^Every call to 9248 ** sqlite3_backup_step() obtains a [shared lock] on the source database that 9249 ** lasts for the duration of the sqlite3_backup_step() call. 9250 ** ^Because the source database is not locked between calls to 9251 ** sqlite3_backup_step(), the source database may be modified mid-way 9252 ** through the backup process. ^If the source database is modified by an 9253 ** external process or via a database connection other than the one being 9254 ** used by the backup operation, then the backup will be automatically 9255 ** restarted by the next call to sqlite3_backup_step(). ^If the source 9256 ** database is modified by the using the same database connection as is used 9257 ** by the backup operation, then the backup database is automatically 9258 ** updated at the same time. 9259 ** 9260 ** [[sqlite3_backup_finish()]] <b>sqlite3_backup_finish()</b> 9261 ** 9262 ** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the 9263 ** application wishes to abandon the backup operation, the application 9264 ** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish(). 9265 ** ^The sqlite3_backup_finish() interfaces releases all 9266 ** resources associated with the [sqlite3_backup] object. 9267 ** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any 9268 ** active write-transaction on the destination database is rolled back. 9269 ** The [sqlite3_backup] object is invalid 9270 ** and may not be used following a call to sqlite3_backup_finish(). 9271 ** 9272 ** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no 9273 ** sqlite3_backup_step() errors occurred, regardless or whether or not 9274 ** sqlite3_backup_step() completed. 9275 ** ^If an out-of-memory condition or IO error occurred during any prior 9276 ** sqlite3_backup_step() call on the same [sqlite3_backup] object, then 9277 ** sqlite3_backup_finish() returns the corresponding [error code]. 9278 ** 9279 ** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step() 9280 ** is not a permanent error and does not affect the return value of 9281 ** sqlite3_backup_finish(). 9282 ** 9283 ** [[sqlite3_backup_remaining()]] [[sqlite3_backup_pagecount()]] 9284 ** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b> 9285 ** 9286 ** ^The sqlite3_backup_remaining() routine returns the number of pages still 9287 ** to be backed up at the conclusion of the most recent sqlite3_backup_step(). 9288 ** ^The sqlite3_backup_pagecount() routine returns the total number of pages 9289 ** in the source database at the conclusion of the most recent 9290 ** sqlite3_backup_step(). 9291 ** ^(The values returned by these functions are only updated by 9292 ** sqlite3_backup_step(). If the source database is modified in a way that 9293 ** changes the size of the source database or the number of pages remaining, 9294 ** those changes are not reflected in the output of sqlite3_backup_pagecount() 9295 ** and sqlite3_backup_remaining() until after the next 9296 ** sqlite3_backup_step().)^ 9297 ** 9298 ** <b>Concurrent Usage of Database Handles</b> 9299 ** 9300 ** ^The source [database connection] may be used by the application for other 9301 ** purposes while a backup operation is underway or being initialized. 9302 ** ^If SQLite is compiled and configured to support threadsafe database 9303 ** connections, then the source database connection may be used concurrently 9304 ** from within other threads. 9305 ** 9306 ** However, the application must guarantee that the destination 9307 ** [database connection] is not passed to any other API (by any thread) after 9308 ** sqlite3_backup_init() is called and before the corresponding call to 9309 ** sqlite3_backup_finish(). SQLite does not currently check to see 9310 ** if the application incorrectly accesses the destination [database connection] 9311 ** and so no error code is reported, but the operations may malfunction 9312 ** nevertheless. Use of the destination database connection while a 9313 ** backup is in progress might also cause a mutex deadlock. 9314 ** 9315 ** If running in [shared cache mode], the application must 9316 ** guarantee that the shared cache used by the destination database 9317 ** is not accessed while the backup is running. In practice this means 9318 ** that the application must guarantee that the disk file being 9319 ** backed up to is not accessed by any connection within the process, 9320 ** not just the specific connection that was passed to sqlite3_backup_init(). 9321 ** 9322 ** The [sqlite3_backup] object itself is partially threadsafe. Multiple 9323 ** threads may safely make multiple concurrent calls to sqlite3_backup_step(). 9324 ** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount() 9325 ** APIs are not strictly speaking threadsafe. If they are invoked at the 9326 ** same time as another thread is invoking sqlite3_backup_step() it is 9327 ** possible that they return invalid values. 9328 */ 9329 SQLITE_API sqlite3_backup *sqlite3_backup_init( 9330 sqlite3 *pDest, /* Destination database handle */ 9331 const char *zDestName, /* Destination database name */ 9332 sqlite3 *pSource, /* Source database handle */ 9333 const char *zSourceName /* Source database name */ 9334 ); 9335 SQLITE_API int sqlite3_backup_step(sqlite3_backup *p, int nPage); 9336 SQLITE_API int sqlite3_backup_finish(sqlite3_backup *p); 9337 SQLITE_API int sqlite3_backup_remaining(sqlite3_backup *p); 9338 SQLITE_API int sqlite3_backup_pagecount(sqlite3_backup *p); 9339 9340 /* 9341 ** CAPI3REF: Unlock Notification 9342 ** METHOD: sqlite3 9343 ** 9344 ** ^When running in shared-cache mode, a database operation may fail with 9345 ** an [SQLITE_LOCKED] error if the required locks on the shared-cache or 9346 ** individual tables within the shared-cache cannot be obtained. See 9347 ** [SQLite Shared-Cache Mode] for a description of shared-cache locking. 9348 ** ^This API may be used to register a callback that SQLite will invoke 9349 ** when the connection currently holding the required lock relinquishes it. 9350 ** ^This API is only available if the library was compiled with the 9351 ** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined. 9352 ** 9353 ** See Also: [Using the SQLite Unlock Notification Feature]. 9354 ** 9355 ** ^Shared-cache locks are released when a database connection concludes 9356 ** its current transaction, either by committing it or rolling it back. 9357 ** 9358 ** ^When a connection (known as the blocked connection) fails to obtain a 9359 ** shared-cache lock and SQLITE_LOCKED is returned to the caller, the 9360 ** identity of the database connection (the blocking connection) that 9361 ** has locked the required resource is stored internally. ^After an 9362 ** application receives an SQLITE_LOCKED error, it may call the 9363 ** sqlite3_unlock_notify() method with the blocked connection handle as 9364 ** the first argument to register for a callback that will be invoked 9365 ** when the blocking connections current transaction is concluded. ^The 9366 ** callback is invoked from within the [sqlite3_step] or [sqlite3_close] 9367 ** call that concludes the blocking connection's transaction. 9368 ** 9369 ** ^(If sqlite3_unlock_notify() is called in a multi-threaded application, 9370 ** there is a chance that the blocking connection will have already 9371 ** concluded its transaction by the time sqlite3_unlock_notify() is invoked. 9372 ** If this happens, then the specified callback is invoked immediately, 9373 ** from within the call to sqlite3_unlock_notify().)^ 9374 ** 9375 ** ^If the blocked connection is attempting to obtain a write-lock on a 9376 ** shared-cache table, and more than one other connection currently holds 9377 ** a read-lock on the same table, then SQLite arbitrarily selects one of 9378 ** the other connections to use as the blocking connection. 9379 ** 9380 ** ^(There may be at most one unlock-notify callback registered by a 9381 ** blocked connection. If sqlite3_unlock_notify() is called when the 9382 ** blocked connection already has a registered unlock-notify callback, 9383 ** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is 9384 ** called with a NULL pointer as its second argument, then any existing 9385 ** unlock-notify callback is canceled. ^The blocked connections 9386 ** unlock-notify callback may also be canceled by closing the blocked 9387 ** connection using [sqlite3_close()]. 9388 ** 9389 ** The unlock-notify callback is not reentrant. If an application invokes 9390 ** any sqlite3_xxx API functions from within an unlock-notify callback, a 9391 ** crash or deadlock may be the result. 9392 ** 9393 ** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always 9394 ** returns SQLITE_OK. 9395 ** 9396 ** <b>Callback Invocation Details</b> 9397 ** 9398 ** When an unlock-notify callback is registered, the application provides a 9399 ** single void* pointer that is passed to the callback when it is invoked. 9400 ** However, the signature of the callback function allows SQLite to pass 9401 ** it an array of void* context pointers. The first argument passed to 9402 ** an unlock-notify callback is a pointer to an array of void* pointers, 9403 ** and the second is the number of entries in the array. 9404 ** 9405 ** When a blocking connection's transaction is concluded, there may be 9406 ** more than one blocked connection that has registered for an unlock-notify 9407 ** callback. ^If two or more such blocked connections have specified the 9408 ** same callback function, then instead of invoking the callback function 9409 ** multiple times, it is invoked once with the set of void* context pointers 9410 ** specified by the blocked connections bundled together into an array. 9411 ** This gives the application an opportunity to prioritize any actions 9412 ** related to the set of unblocked database connections. 9413 ** 9414 ** <b>Deadlock Detection</b> 9415 ** 9416 ** Assuming that after registering for an unlock-notify callback a 9417 ** database waits for the callback to be issued before taking any further 9418 ** action (a reasonable assumption), then using this API may cause the 9419 ** application to deadlock. For example, if connection X is waiting for 9420 ** connection Y's transaction to be concluded, and similarly connection 9421 ** Y is waiting on connection X's transaction, then neither connection 9422 ** will proceed and the system may remain deadlocked indefinitely. 9423 ** 9424 ** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock 9425 ** detection. ^If a given call to sqlite3_unlock_notify() would put the 9426 ** system in a deadlocked state, then SQLITE_LOCKED is returned and no 9427 ** unlock-notify callback is registered. The system is said to be in 9428 ** a deadlocked state if connection A has registered for an unlock-notify 9429 ** callback on the conclusion of connection B's transaction, and connection 9430 ** B has itself registered for an unlock-notify callback when connection 9431 ** A's transaction is concluded. ^Indirect deadlock is also detected, so 9432 ** the system is also considered to be deadlocked if connection B has 9433 ** registered for an unlock-notify callback on the conclusion of connection 9434 ** C's transaction, where connection C is waiting on connection A. ^Any 9435 ** number of levels of indirection are allowed. 9436 ** 9437 ** <b>The "DROP TABLE" Exception</b> 9438 ** 9439 ** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost 9440 ** always appropriate to call sqlite3_unlock_notify(). There is however, 9441 ** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement, 9442 ** SQLite checks if there are any currently executing SELECT statements 9443 ** that belong to the same connection. If there are, SQLITE_LOCKED is 9444 ** returned. In this case there is no "blocking connection", so invoking 9445 ** sqlite3_unlock_notify() results in the unlock-notify callback being 9446 ** invoked immediately. If the application then re-attempts the "DROP TABLE" 9447 ** or "DROP INDEX" query, an infinite loop might be the result. 9448 ** 9449 ** One way around this problem is to check the extended error code returned 9450 ** by an sqlite3_step() call. ^(If there is a blocking connection, then the 9451 ** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in 9452 ** the special "DROP TABLE/INDEX" case, the extended error code is just 9453 ** SQLITE_LOCKED.)^ 9454 */ 9455 SQLITE_API int sqlite3_unlock_notify( 9456 sqlite3 *pBlocked, /* Waiting connection */ 9457 void (*xNotify)(void **apArg, int nArg), /* Callback function to invoke */ 9458 void *pNotifyArg /* Argument to pass to xNotify */ 9459 ); 9460 9461 9462 /* 9463 ** CAPI3REF: String Comparison 9464 ** 9465 ** ^The [sqlite3_stricmp()] and [sqlite3_strnicmp()] APIs allow applications 9466 ** and extensions to compare the contents of two buffers containing UTF-8 9467 ** strings in a case-independent fashion, using the same definition of "case 9468 ** independence" that SQLite uses internally when comparing identifiers. 9469 */ 9470 SQLITE_API int sqlite3_stricmp(const char *, const char *); 9471 SQLITE_API int sqlite3_strnicmp(const char *, const char *, int); 9472 9473 /* 9474 ** CAPI3REF: String Globbing 9475 * 9476 ** ^The [sqlite3_strglob(P,X)] interface returns zero if and only if 9477 ** string X matches the [GLOB] pattern P. 9478 ** ^The definition of [GLOB] pattern matching used in 9479 ** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the 9480 ** SQL dialect understood by SQLite. ^The [sqlite3_strglob(P,X)] function 9481 ** is case sensitive. 9482 ** 9483 ** Note that this routine returns zero on a match and non-zero if the strings 9484 ** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()]. 9485 ** 9486 ** See also: [sqlite3_strlike()]. 9487 */ 9488 SQLITE_API int sqlite3_strglob(const char *zGlob, const char *zStr); 9489 9490 /* 9491 ** CAPI3REF: String LIKE Matching 9492 * 9493 ** ^The [sqlite3_strlike(P,X,E)] interface returns zero if and only if 9494 ** string X matches the [LIKE] pattern P with escape character E. 9495 ** ^The definition of [LIKE] pattern matching used in 9496 ** [sqlite3_strlike(P,X,E)] is the same as for the "X LIKE P ESCAPE E" 9497 ** operator in the SQL dialect understood by SQLite. ^For "X LIKE P" without 9498 ** the ESCAPE clause, set the E parameter of [sqlite3_strlike(P,X,E)] to 0. 9499 ** ^As with the LIKE operator, the [sqlite3_strlike(P,X,E)] function is case 9500 ** insensitive - equivalent upper and lower case ASCII characters match 9501 ** one another. 9502 ** 9503 ** ^The [sqlite3_strlike(P,X,E)] function matches Unicode characters, though 9504 ** only ASCII characters are case folded. 9505 ** 9506 ** Note that this routine returns zero on a match and non-zero if the strings 9507 ** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()]. 9508 ** 9509 ** See also: [sqlite3_strglob()]. 9510 */ 9511 SQLITE_API int sqlite3_strlike(const char *zGlob, const char *zStr, unsigned int cEsc); 9512 9513 /* 9514 ** CAPI3REF: Error Logging Interface 9515 ** 9516 ** ^The [sqlite3_log()] interface writes a message into the [error log] 9517 ** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()]. 9518 ** ^If logging is enabled, the zFormat string and subsequent arguments are 9519 ** used with [sqlite3_snprintf()] to generate the final output string. 9520 ** 9521 ** The sqlite3_log() interface is intended for use by extensions such as 9522 ** virtual tables, collating functions, and SQL functions. While there is 9523 ** nothing to prevent an application from calling sqlite3_log(), doing so 9524 ** is considered bad form. 9525 ** 9526 ** The zFormat string must not be NULL. 9527 ** 9528 ** To avoid deadlocks and other threading problems, the sqlite3_log() routine 9529 ** will not use dynamically allocated memory. The log message is stored in 9530 ** a fixed-length buffer on the stack. If the log message is longer than 9531 ** a few hundred characters, it will be truncated to the length of the 9532 ** buffer. 9533 */ 9534 SQLITE_API void sqlite3_log(int iErrCode, const char *zFormat, ...); 9535 9536 /* 9537 ** CAPI3REF: Write-Ahead Log Commit Hook 9538 ** METHOD: sqlite3 9539 ** 9540 ** ^The [sqlite3_wal_hook()] function is used to register a callback that 9541 ** is invoked each time data is committed to a database in wal mode. 9542 ** 9543 ** ^(The callback is invoked by SQLite after the commit has taken place and 9544 ** the associated write-lock on the database released)^, so the implementation 9545 ** may read, write or [checkpoint] the database as required. 9546 ** 9547 ** ^The first parameter passed to the callback function when it is invoked 9548 ** is a copy of the third parameter passed to sqlite3_wal_hook() when 9549 ** registering the callback. ^The second is a copy of the database handle. 9550 ** ^The third parameter is the name of the database that was written to - 9551 ** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter 9552 ** is the number of pages currently in the write-ahead log file, 9553 ** including those that were just committed. 9554 ** 9555 ** The callback function should normally return [SQLITE_OK]. ^If an error 9556 ** code is returned, that error will propagate back up through the 9557 ** SQLite code base to cause the statement that provoked the callback 9558 ** to report an error, though the commit will have still occurred. If the 9559 ** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value 9560 ** that does not correspond to any valid SQLite error code, the results 9561 ** are undefined. 9562 ** 9563 ** A single database handle may have at most a single write-ahead log callback 9564 ** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any 9565 ** previously registered write-ahead log callback. ^The return value is 9566 ** a copy of the third parameter from the previous call, if any, or 0. 9567 ** ^Note that the [sqlite3_wal_autocheckpoint()] interface and the 9568 ** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will 9569 ** overwrite any prior [sqlite3_wal_hook()] settings. 9570 */ 9571 SQLITE_API void *sqlite3_wal_hook( 9572 sqlite3*, 9573 int(*)(void *,sqlite3*,const char*,int), 9574 void* 9575 ); 9576 9577 /* 9578 ** CAPI3REF: Configure an auto-checkpoint 9579 ** METHOD: sqlite3 9580 ** 9581 ** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around 9582 ** [sqlite3_wal_hook()] that causes any database on [database connection] D 9583 ** to automatically [checkpoint] 9584 ** after committing a transaction if there are N or 9585 ** more frames in the [write-ahead log] file. ^Passing zero or 9586 ** a negative value as the nFrame parameter disables automatic 9587 ** checkpoints entirely. 9588 ** 9589 ** ^The callback registered by this function replaces any existing callback 9590 ** registered using [sqlite3_wal_hook()]. ^Likewise, registering a callback 9591 ** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism 9592 ** configured by this function. 9593 ** 9594 ** ^The [wal_autocheckpoint pragma] can be used to invoke this interface 9595 ** from SQL. 9596 ** 9597 ** ^Checkpoints initiated by this mechanism are 9598 ** [sqlite3_wal_checkpoint_v2|PASSIVE]. 9599 ** 9600 ** ^Every new [database connection] defaults to having the auto-checkpoint 9601 ** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT] 9602 ** pages. The use of this interface 9603 ** is only necessary if the default setting is found to be suboptimal 9604 ** for a particular application. 9605 */ 9606 SQLITE_API int sqlite3_wal_autocheckpoint(sqlite3 *db, int N); 9607 9608 /* 9609 ** CAPI3REF: Checkpoint a database 9610 ** METHOD: sqlite3 9611 ** 9612 ** ^(The sqlite3_wal_checkpoint(D,X) is equivalent to 9613 ** [sqlite3_wal_checkpoint_v2](D,X,[SQLITE_CHECKPOINT_PASSIVE],0,0).)^ 9614 ** 9615 ** In brief, sqlite3_wal_checkpoint(D,X) causes the content in the 9616 ** [write-ahead log] for database X on [database connection] D to be 9617 ** transferred into the database file and for the write-ahead log to 9618 ** be reset. See the [checkpointing] documentation for addition 9619 ** information. 9620 ** 9621 ** This interface used to be the only way to cause a checkpoint to 9622 ** occur. But then the newer and more powerful [sqlite3_wal_checkpoint_v2()] 9623 ** interface was added. This interface is retained for backwards 9624 ** compatibility and as a convenience for applications that need to manually 9625 ** start a callback but which do not need the full power (and corresponding 9626 ** complication) of [sqlite3_wal_checkpoint_v2()]. 9627 */ 9628 SQLITE_API int sqlite3_wal_checkpoint(sqlite3 *db, const char *zDb); 9629 9630 /* 9631 ** CAPI3REF: Checkpoint a database 9632 ** METHOD: sqlite3 9633 ** 9634 ** ^(The sqlite3_wal_checkpoint_v2(D,X,M,L,C) interface runs a checkpoint 9635 ** operation on database X of [database connection] D in mode M. Status 9636 ** information is written back into integers pointed to by L and C.)^ 9637 ** ^(The M parameter must be a valid [checkpoint mode]:)^ 9638 ** 9639 ** <dl> 9640 ** <dt>SQLITE_CHECKPOINT_PASSIVE<dd> 9641 ** ^Checkpoint as many frames as possible without waiting for any database 9642 ** readers or writers to finish, then sync the database file if all frames 9643 ** in the log were checkpointed. ^The [busy-handler callback] 9644 ** is never invoked in the SQLITE_CHECKPOINT_PASSIVE mode. 9645 ** ^On the other hand, passive mode might leave the checkpoint unfinished 9646 ** if there are concurrent readers or writers. 9647 ** 9648 ** <dt>SQLITE_CHECKPOINT_FULL<dd> 9649 ** ^This mode blocks (it invokes the 9650 ** [sqlite3_busy_handler|busy-handler callback]) until there is no 9651 ** database writer and all readers are reading from the most recent database 9652 ** snapshot. ^It then checkpoints all frames in the log file and syncs the 9653 ** database file. ^This mode blocks new database writers while it is pending, 9654 ** but new database readers are allowed to continue unimpeded. 9655 ** 9656 ** <dt>SQLITE_CHECKPOINT_RESTART<dd> 9657 ** ^This mode works the same way as SQLITE_CHECKPOINT_FULL with the addition 9658 ** that after checkpointing the log file it blocks (calls the 9659 ** [busy-handler callback]) 9660 ** until all readers are reading from the database file only. ^This ensures 9661 ** that the next writer will restart the log file from the beginning. 9662 ** ^Like SQLITE_CHECKPOINT_FULL, this mode blocks new 9663 ** database writer attempts while it is pending, but does not impede readers. 9664 ** 9665 ** <dt>SQLITE_CHECKPOINT_TRUNCATE<dd> 9666 ** ^This mode works the same way as SQLITE_CHECKPOINT_RESTART with the 9667 ** addition that it also truncates the log file to zero bytes just prior 9668 ** to a successful return. 9669 ** </dl> 9670 ** 9671 ** ^If pnLog is not NULL, then *pnLog is set to the total number of frames in 9672 ** the log file or to -1 if the checkpoint could not run because 9673 ** of an error or because the database is not in [WAL mode]. ^If pnCkpt is not 9674 ** NULL,then *pnCkpt is set to the total number of checkpointed frames in the 9675 ** log file (including any that were already checkpointed before the function 9676 ** was called) or to -1 if the checkpoint could not run due to an error or 9677 ** because the database is not in WAL mode. ^Note that upon successful 9678 ** completion of an SQLITE_CHECKPOINT_TRUNCATE, the log file will have been 9679 ** truncated to zero bytes and so both *pnLog and *pnCkpt will be set to zero. 9680 ** 9681 ** ^All calls obtain an exclusive "checkpoint" lock on the database file. ^If 9682 ** any other process is running a checkpoint operation at the same time, the 9683 ** lock cannot be obtained and SQLITE_BUSY is returned. ^Even if there is a 9684 ** busy-handler configured, it will not be invoked in this case. 9685 ** 9686 ** ^The SQLITE_CHECKPOINT_FULL, RESTART and TRUNCATE modes also obtain the 9687 ** exclusive "writer" lock on the database file. ^If the writer lock cannot be 9688 ** obtained immediately, and a busy-handler is configured, it is invoked and 9689 ** the writer lock retried until either the busy-handler returns 0 or the lock 9690 ** is successfully obtained. ^The busy-handler is also invoked while waiting for 9691 ** database readers as described above. ^If the busy-handler returns 0 before 9692 ** the writer lock is obtained or while waiting for database readers, the 9693 ** checkpoint operation proceeds from that point in the same way as 9694 ** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible 9695 ** without blocking any further. ^SQLITE_BUSY is returned in this case. 9696 ** 9697 ** ^If parameter zDb is NULL or points to a zero length string, then the 9698 ** specified operation is attempted on all WAL databases [attached] to 9699 ** [database connection] db. In this case the 9700 ** values written to output parameters *pnLog and *pnCkpt are undefined. ^If 9701 ** an SQLITE_BUSY error is encountered when processing one or more of the 9702 ** attached WAL databases, the operation is still attempted on any remaining 9703 ** attached databases and SQLITE_BUSY is returned at the end. ^If any other 9704 ** error occurs while processing an attached database, processing is abandoned 9705 ** and the error code is returned to the caller immediately. ^If no error 9706 ** (SQLITE_BUSY or otherwise) is encountered while processing the attached 9707 ** databases, SQLITE_OK is returned. 9708 ** 9709 ** ^If database zDb is the name of an attached database that is not in WAL 9710 ** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. ^If 9711 ** zDb is not NULL (or a zero length string) and is not the name of any 9712 ** attached database, SQLITE_ERROR is returned to the caller. 9713 ** 9714 ** ^Unless it returns SQLITE_MISUSE, 9715 ** the sqlite3_wal_checkpoint_v2() interface 9716 ** sets the error information that is queried by 9717 ** [sqlite3_errcode()] and [sqlite3_errmsg()]. 9718 ** 9719 ** ^The [PRAGMA wal_checkpoint] command can be used to invoke this interface 9720 ** from SQL. 9721 */ 9722 SQLITE_API int sqlite3_wal_checkpoint_v2( 9723 sqlite3 *db, /* Database handle */ 9724 const char *zDb, /* Name of attached database (or NULL) */ 9725 int eMode, /* SQLITE_CHECKPOINT_* value */ 9726 int *pnLog, /* OUT: Size of WAL log in frames */ 9727 int *pnCkpt /* OUT: Total number of frames checkpointed */ 9728 ); 9729 9730 /* 9731 ** CAPI3REF: Checkpoint Mode Values 9732 ** KEYWORDS: {checkpoint mode} 9733 ** 9734 ** These constants define all valid values for the "checkpoint mode" passed 9735 ** as the third parameter to the [sqlite3_wal_checkpoint_v2()] interface. 9736 ** See the [sqlite3_wal_checkpoint_v2()] documentation for details on the 9737 ** meaning of each of these checkpoint modes. 9738 */ 9739 #define SQLITE_CHECKPOINT_PASSIVE 0 /* Do as much as possible w/o blocking */ 9740 #define SQLITE_CHECKPOINT_FULL 1 /* Wait for writers, then checkpoint */ 9741 #define SQLITE_CHECKPOINT_RESTART 2 /* Like FULL but wait for readers */ 9742 #define SQLITE_CHECKPOINT_TRUNCATE 3 /* Like RESTART but also truncate WAL */ 9743 9744 /* 9745 ** CAPI3REF: Virtual Table Interface Configuration 9746 ** 9747 ** This function may be called by either the [xConnect] or [xCreate] method 9748 ** of a [virtual table] implementation to configure 9749 ** various facets of the virtual table interface. 9750 ** 9751 ** If this interface is invoked outside the context of an xConnect or 9752 ** xCreate virtual table method then the behavior is undefined. 9753 ** 9754 ** In the call sqlite3_vtab_config(D,C,...) the D parameter is the 9755 ** [database connection] in which the virtual table is being created and 9756 ** which is passed in as the first argument to the [xConnect] or [xCreate] 9757 ** method that is invoking sqlite3_vtab_config(). The C parameter is one 9758 ** of the [virtual table configuration options]. The presence and meaning 9759 ** of parameters after C depend on which [virtual table configuration option] 9760 ** is used. 9761 */ 9762 SQLITE_API int sqlite3_vtab_config(sqlite3*, int op, ...); 9763 9764 /* 9765 ** CAPI3REF: Virtual Table Configuration Options 9766 ** KEYWORDS: {virtual table configuration options} 9767 ** KEYWORDS: {virtual table configuration option} 9768 ** 9769 ** These macros define the various options to the 9770 ** [sqlite3_vtab_config()] interface that [virtual table] implementations 9771 ** can use to customize and optimize their behavior. 9772 ** 9773 ** <dl> 9774 ** [[SQLITE_VTAB_CONSTRAINT_SUPPORT]] 9775 ** <dt>SQLITE_VTAB_CONSTRAINT_SUPPORT</dt> 9776 ** <dd>Calls of the form 9777 ** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported, 9778 ** where X is an integer. If X is zero, then the [virtual table] whose 9779 ** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not 9780 ** support constraints. In this configuration (which is the default) if 9781 ** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire 9782 ** statement is rolled back as if [ON CONFLICT | OR ABORT] had been 9783 ** specified as part of the users SQL statement, regardless of the actual 9784 ** ON CONFLICT mode specified. 9785 ** 9786 ** If X is non-zero, then the virtual table implementation guarantees 9787 ** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before 9788 ** any modifications to internal or persistent data structures have been made. 9789 ** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite 9790 ** is able to roll back a statement or database transaction, and abandon 9791 ** or continue processing the current SQL statement as appropriate. 9792 ** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns 9793 ** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode 9794 ** had been ABORT. 9795 ** 9796 ** Virtual table implementations that are required to handle OR REPLACE 9797 ** must do so within the [xUpdate] method. If a call to the 9798 ** [sqlite3_vtab_on_conflict()] function indicates that the current ON 9799 ** CONFLICT policy is REPLACE, the virtual table implementation should 9800 ** silently replace the appropriate rows within the xUpdate callback and 9801 ** return SQLITE_OK. Or, if this is not possible, it may return 9802 ** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT 9803 ** constraint handling. 9804 ** </dd> 9805 ** 9806 ** [[SQLITE_VTAB_DIRECTONLY]]<dt>SQLITE_VTAB_DIRECTONLY</dt> 9807 ** <dd>Calls of the form 9808 ** [sqlite3_vtab_config](db,SQLITE_VTAB_DIRECTONLY) from within the 9809 ** the [xConnect] or [xCreate] methods of a [virtual table] implementation 9810 ** prohibits that virtual table from being used from within triggers and 9811 ** views. 9812 ** </dd> 9813 ** 9814 ** [[SQLITE_VTAB_INNOCUOUS]]<dt>SQLITE_VTAB_INNOCUOUS</dt> 9815 ** <dd>Calls of the form 9816 ** [sqlite3_vtab_config](db,SQLITE_VTAB_INNOCUOUS) from within the 9817 ** the [xConnect] or [xCreate] methods of a [virtual table] implementation 9818 ** identify that virtual table as being safe to use from within triggers 9819 ** and views. Conceptually, the SQLITE_VTAB_INNOCUOUS tag means that the 9820 ** virtual table can do no serious harm even if it is controlled by a 9821 ** malicious hacker. Developers should avoid setting the SQLITE_VTAB_INNOCUOUS 9822 ** flag unless absolutely necessary. 9823 ** </dd> 9824 ** 9825 ** [[SQLITE_VTAB_USES_ALL_SCHEMAS]]<dt>SQLITE_VTAB_USES_ALL_SCHEMAS</dt> 9826 ** <dd>Calls of the form 9827 ** [sqlite3_vtab_config](db,SQLITE_VTAB_USES_ALL_SCHEMA) from within the 9828 ** the [xConnect] or [xCreate] methods of a [virtual table] implementation 9829 ** instruct the query planner to begin at least a read transaction on 9830 ** all schemas ("main", "temp", and any ATTACH-ed databases) whenever the 9831 ** virtual table is used. 9832 ** </dd> 9833 ** </dl> 9834 */ 9835 #define SQLITE_VTAB_CONSTRAINT_SUPPORT 1 9836 #define SQLITE_VTAB_INNOCUOUS 2 9837 #define SQLITE_VTAB_DIRECTONLY 3 9838 #define SQLITE_VTAB_USES_ALL_SCHEMAS 4 9839 9840 /* 9841 ** CAPI3REF: Determine The Virtual Table Conflict Policy 9842 ** 9843 ** This function may only be called from within a call to the [xUpdate] method 9844 ** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The 9845 ** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL], 9846 ** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode 9847 ** of the SQL statement that triggered the call to the [xUpdate] method of the 9848 ** [virtual table]. 9849 */ 9850 SQLITE_API int sqlite3_vtab_on_conflict(sqlite3 *); 9851 9852 /* 9853 ** CAPI3REF: Determine If Virtual Table Column Access Is For UPDATE 9854 ** 9855 ** If the sqlite3_vtab_nochange(X) routine is called within the [xColumn] 9856 ** method of a [virtual table], then it might return true if the 9857 ** column is being fetched as part of an UPDATE operation during which the 9858 ** column value will not change. The virtual table implementation can use 9859 ** this hint as permission to substitute a return value that is less 9860 ** expensive to compute and that the corresponding 9861 ** [xUpdate] method understands as a "no-change" value. 9862 ** 9863 ** If the [xColumn] method calls sqlite3_vtab_nochange() and finds that 9864 ** the column is not changed by the UPDATE statement, then the xColumn 9865 ** method can optionally return without setting a result, without calling 9866 ** any of the [sqlite3_result_int|sqlite3_result_xxxxx() interfaces]. 9867 ** In that case, [sqlite3_value_nochange(X)] will return true for the 9868 ** same column in the [xUpdate] method. 9869 ** 9870 ** The sqlite3_vtab_nochange() routine is an optimization. Virtual table 9871 ** implementations should continue to give a correct answer even if the 9872 ** sqlite3_vtab_nochange() interface were to always return false. In the 9873 ** current implementation, the sqlite3_vtab_nochange() interface does always 9874 ** returns false for the enhanced [UPDATE FROM] statement. 9875 */ 9876 SQLITE_API int sqlite3_vtab_nochange(sqlite3_context*); 9877 9878 /* 9879 ** CAPI3REF: Determine The Collation For a Virtual Table Constraint 9880 ** METHOD: sqlite3_index_info 9881 ** 9882 ** This function may only be called from within a call to the [xBestIndex] 9883 ** method of a [virtual table]. This function returns a pointer to a string 9884 ** that is the name of the appropriate collation sequence to use for text 9885 ** comparisons on the constraint identified by its arguments. 9886 ** 9887 ** The first argument must be the pointer to the [sqlite3_index_info] object 9888 ** that is the first parameter to the xBestIndex() method. The second argument 9889 ** must be an index into the aConstraint[] array belonging to the 9890 ** sqlite3_index_info structure passed to xBestIndex. 9891 ** 9892 ** Important: 9893 ** The first parameter must be the same pointer that is passed into the 9894 ** xBestMethod() method. The first parameter may not be a pointer to a 9895 ** different [sqlite3_index_info] object, even an exact copy. 9896 ** 9897 ** The return value is computed as follows: 9898 ** 9899 ** <ol> 9900 ** <li><p> If the constraint comes from a WHERE clause expression that contains 9901 ** a [COLLATE operator], then the name of the collation specified by 9902 ** that COLLATE operator is returned. 9903 ** <li><p> If there is no COLLATE operator, but the column that is the subject 9904 ** of the constraint specifies an alternative collating sequence via 9905 ** a [COLLATE clause] on the column definition within the CREATE TABLE 9906 ** statement that was passed into [sqlite3_declare_vtab()], then the 9907 ** name of that alternative collating sequence is returned. 9908 ** <li><p> Otherwise, "BINARY" is returned. 9909 ** </ol> 9910 */ 9911 SQLITE_API const char *sqlite3_vtab_collation(sqlite3_index_info*,int); 9912 9913 /* 9914 ** CAPI3REF: Determine if a virtual table query is DISTINCT 9915 ** METHOD: sqlite3_index_info 9916 ** 9917 ** This API may only be used from within an [xBestIndex|xBestIndex method] 9918 ** of a [virtual table] implementation. The result of calling this 9919 ** interface from outside of xBestIndex() is undefined and probably harmful. 9920 ** 9921 ** ^The sqlite3_vtab_distinct() interface returns an integer between 0 and 9922 ** 3. The integer returned by sqlite3_vtab_distinct() 9923 ** gives the virtual table additional information about how the query 9924 ** planner wants the output to be ordered. As long as the virtual table 9925 ** can meet the ordering requirements of the query planner, it may set 9926 ** the "orderByConsumed" flag. 9927 ** 9928 ** <ol><li value="0"><p> 9929 ** ^If the sqlite3_vtab_distinct() interface returns 0, that means 9930 ** that the query planner needs the virtual table to return all rows in the 9931 ** sort order defined by the "nOrderBy" and "aOrderBy" fields of the 9932 ** [sqlite3_index_info] object. This is the default expectation. If the 9933 ** virtual table outputs all rows in sorted order, then it is always safe for 9934 ** the xBestIndex method to set the "orderByConsumed" flag, regardless of 9935 ** the return value from sqlite3_vtab_distinct(). 9936 ** <li value="1"><p> 9937 ** ^(If the sqlite3_vtab_distinct() interface returns 1, that means 9938 ** that the query planner does not need the rows to be returned in sorted order 9939 ** as long as all rows with the same values in all columns identified by the 9940 ** "aOrderBy" field are adjacent.)^ This mode is used when the query planner 9941 ** is doing a GROUP BY. 9942 ** <li value="2"><p> 9943 ** ^(If the sqlite3_vtab_distinct() interface returns 2, that means 9944 ** that the query planner does not need the rows returned in any particular 9945 ** order, as long as rows with the same values in all columns identified 9946 ** by "aOrderBy" are adjacent.)^ ^(Furthermore, when two or more rows 9947 ** contain the same values for all columns identified by "colUsed", all but 9948 ** one such row may optionally be omitted from the result.)^ 9949 ** The virtual table is not required to omit rows that are duplicates 9950 ** over the "colUsed" columns, but if the virtual table can do that without 9951 ** too much extra effort, it could potentially help the query to run faster. 9952 ** This mode is used for a DISTINCT query. 9953 ** <li value="3"><p> 9954 ** ^(If the sqlite3_vtab_distinct() interface returns 3, that means the 9955 ** virtual table must return rows in the order defined by "aOrderBy" as 9956 ** if the sqlite3_vtab_distinct() interface had returned 0. However if 9957 ** two or more rows in the result have the same values for all columns 9958 ** identified by "colUsed", then all but one such row may optionally be 9959 ** omitted.)^ Like when the return value is 2, the virtual table 9960 ** is not required to omit rows that are duplicates over the "colUsed" 9961 ** columns, but if the virtual table can do that without 9962 ** too much extra effort, it could potentially help the query to run faster. 9963 ** This mode is used for queries 9964 ** that have both DISTINCT and ORDER BY clauses. 9965 ** </ol> 9966 ** 9967 ** <p>The following table summarizes the conditions under which the 9968 ** virtual table is allowed to set the "orderByConsumed" flag based on 9969 ** the value returned by sqlite3_vtab_distinct(). This table is a 9970 ** restatement of the previous four paragraphs: 9971 ** 9972 ** <table border=1 cellspacing=0 cellpadding=10 width="90%"> 9973 ** <tr> 9974 ** <td valign="top">sqlite3_vtab_distinct() return value 9975 ** <td valign="top">Rows are returned in aOrderBy order 9976 ** <td valign="top">Rows with the same value in all aOrderBy columns are adjacent 9977 ** <td valign="top">Duplicates over all colUsed columns may be omitted 9978 ** <tr><td>0<td>yes<td>yes<td>no 9979 ** <tr><td>1<td>no<td>yes<td>no 9980 ** <tr><td>2<td>no<td>yes<td>yes 9981 ** <tr><td>3<td>yes<td>yes<td>yes 9982 ** </table> 9983 ** 9984 ** ^For the purposes of comparing virtual table output values to see if the 9985 ** values are same value for sorting purposes, two NULL values are considered 9986 ** to be the same. In other words, the comparison operator is "IS" 9987 ** (or "IS NOT DISTINCT FROM") and not "==". 9988 ** 9989 ** If a virtual table implementation is unable to meet the requirements 9990 ** specified above, then it must not set the "orderByConsumed" flag in the 9991 ** [sqlite3_index_info] object or an incorrect answer may result. 9992 ** 9993 ** ^A virtual table implementation is always free to return rows in any order 9994 ** it wants, as long as the "orderByConsumed" flag is not set. ^When the 9995 ** the "orderByConsumed" flag is unset, the query planner will add extra 9996 ** [bytecode] to ensure that the final results returned by the SQL query are 9997 ** ordered correctly. The use of the "orderByConsumed" flag and the 9998 ** sqlite3_vtab_distinct() interface is merely an optimization. ^Careful 9999 ** use of the sqlite3_vtab_distinct() interface and the "orderByConsumed" 10000 ** flag might help queries against a virtual table to run faster. Being 10001 ** overly aggressive and setting the "orderByConsumed" flag when it is not 10002 ** valid to do so, on the other hand, might cause SQLite to return incorrect 10003 ** results. 10004 */ 10005 SQLITE_API int sqlite3_vtab_distinct(sqlite3_index_info*); 10006 10007 /* 10008 ** CAPI3REF: Identify and handle IN constraints in xBestIndex 10009 ** 10010 ** This interface may only be used from within an 10011 ** [xBestIndex|xBestIndex() method] of a [virtual table] implementation. 10012 ** The result of invoking this interface from any other context is 10013 ** undefined and probably harmful. 10014 ** 10015 ** ^(A constraint on a virtual table of the form 10016 ** "[IN operator|column IN (...)]" is 10017 ** communicated to the xBestIndex method as a 10018 ** [SQLITE_INDEX_CONSTRAINT_EQ] constraint.)^ If xBestIndex wants to use 10019 ** this constraint, it must set the corresponding 10020 ** aConstraintUsage[].argvIndex to a positive integer. ^(Then, under 10021 ** the usual mode of handling IN operators, SQLite generates [bytecode] 10022 ** that invokes the [xFilter|xFilter() method] once for each value 10023 ** on the right-hand side of the IN operator.)^ Thus the virtual table 10024 ** only sees a single value from the right-hand side of the IN operator 10025 ** at a time. 10026 ** 10027 ** In some cases, however, it would be advantageous for the virtual 10028 ** table to see all values on the right-hand of the IN operator all at 10029 ** once. The sqlite3_vtab_in() interfaces facilitates this in two ways: 10030 ** 10031 ** <ol> 10032 ** <li><p> 10033 ** ^A call to sqlite3_vtab_in(P,N,-1) will return true (non-zero) 10034 ** if and only if the [sqlite3_index_info|P->aConstraint][N] constraint 10035 ** is an [IN operator] that can be processed all at once. ^In other words, 10036 ** sqlite3_vtab_in() with -1 in the third argument is a mechanism 10037 ** by which the virtual table can ask SQLite if all-at-once processing 10038 ** of the IN operator is even possible. 10039 ** 10040 ** <li><p> 10041 ** ^A call to sqlite3_vtab_in(P,N,F) with F==1 or F==0 indicates 10042 ** to SQLite that the virtual table does or does not want to process 10043 ** the IN operator all-at-once, respectively. ^Thus when the third 10044 ** parameter (F) is non-negative, this interface is the mechanism by 10045 ** which the virtual table tells SQLite how it wants to process the 10046 ** IN operator. 10047 ** </ol> 10048 ** 10049 ** ^The sqlite3_vtab_in(P,N,F) interface can be invoked multiple times 10050 ** within the same xBestIndex method call. ^For any given P,N pair, 10051 ** the return value from sqlite3_vtab_in(P,N,F) will always be the same 10052 ** within the same xBestIndex call. ^If the interface returns true 10053 ** (non-zero), that means that the constraint is an IN operator 10054 ** that can be processed all-at-once. ^If the constraint is not an IN 10055 ** operator or cannot be processed all-at-once, then the interface returns 10056 ** false. 10057 ** 10058 ** ^(All-at-once processing of the IN operator is selected if both of the 10059 ** following conditions are met: 10060 ** 10061 ** <ol> 10062 ** <li><p> The P->aConstraintUsage[N].argvIndex value is set to a positive 10063 ** integer. This is how the virtual table tells SQLite that it wants to 10064 ** use the N-th constraint. 10065 ** 10066 ** <li><p> The last call to sqlite3_vtab_in(P,N,F) for which F was 10067 ** non-negative had F>=1. 10068 ** </ol>)^ 10069 ** 10070 ** ^If either or both of the conditions above are false, then SQLite uses 10071 ** the traditional one-at-a-time processing strategy for the IN constraint. 10072 ** ^If both conditions are true, then the argvIndex-th parameter to the 10073 ** xFilter method will be an [sqlite3_value] that appears to be NULL, 10074 ** but which can be passed to [sqlite3_vtab_in_first()] and 10075 ** [sqlite3_vtab_in_next()] to find all values on the right-hand side 10076 ** of the IN constraint. 10077 */ 10078 SQLITE_API int sqlite3_vtab_in(sqlite3_index_info*, int iCons, int bHandle); 10079 10080 /* 10081 ** CAPI3REF: Find all elements on the right-hand side of an IN constraint. 10082 ** 10083 ** These interfaces are only useful from within the 10084 ** [xFilter|xFilter() method] of a [virtual table] implementation. 10085 ** The result of invoking these interfaces from any other context 10086 ** is undefined and probably harmful. 10087 ** 10088 ** The X parameter in a call to sqlite3_vtab_in_first(X,P) or 10089 ** sqlite3_vtab_in_next(X,P) should be one of the parameters to the 10090 ** xFilter method which invokes these routines, and specifically 10091 ** a parameter that was previously selected for all-at-once IN constraint 10092 ** processing use the [sqlite3_vtab_in()] interface in the 10093 ** [xBestIndex|xBestIndex method]. ^(If the X parameter is not 10094 ** an xFilter argument that was selected for all-at-once IN constraint 10095 ** processing, then these routines return [SQLITE_ERROR].)^ 10096 ** 10097 ** ^(Use these routines to access all values on the right-hand side 10098 ** of the IN constraint using code like the following: 10099 ** 10100 ** <blockquote><pre> 10101 ** for(rc=sqlite3_vtab_in_first(pList, &pVal); 10102 ** rc==SQLITE_OK && pVal; 10103 ** rc=sqlite3_vtab_in_next(pList, &pVal) 10104 ** ){ 10105 ** // do something with pVal 10106 ** } 10107 ** if( rc!=SQLITE_OK ){ 10108 ** // an error has occurred 10109 ** } 10110 ** </pre></blockquote>)^ 10111 ** 10112 ** ^On success, the sqlite3_vtab_in_first(X,P) and sqlite3_vtab_in_next(X,P) 10113 ** routines return SQLITE_OK and set *P to point to the first or next value 10114 ** on the RHS of the IN constraint. ^If there are no more values on the 10115 ** right hand side of the IN constraint, then *P is set to NULL and these 10116 ** routines return [SQLITE_DONE]. ^The return value might be 10117 ** some other value, such as SQLITE_NOMEM, in the event of a malfunction. 10118 ** 10119 ** The *ppOut values returned by these routines are only valid until the 10120 ** next call to either of these routines or until the end of the xFilter 10121 ** method from which these routines were called. If the virtual table 10122 ** implementation needs to retain the *ppOut values for longer, it must make 10123 ** copies. The *ppOut values are [protected sqlite3_value|protected]. 10124 */ 10125 SQLITE_API int sqlite3_vtab_in_first(sqlite3_value *pVal, sqlite3_value **ppOut); 10126 SQLITE_API int sqlite3_vtab_in_next(sqlite3_value *pVal, sqlite3_value **ppOut); 10127 10128 /* 10129 ** CAPI3REF: Constraint values in xBestIndex() 10130 ** METHOD: sqlite3_index_info 10131 ** 10132 ** This API may only be used from within the [xBestIndex|xBestIndex method] 10133 ** of a [virtual table] implementation. The result of calling this interface 10134 ** from outside of an xBestIndex method are undefined and probably harmful. 10135 ** 10136 ** ^When the sqlite3_vtab_rhs_value(P,J,V) interface is invoked from within 10137 ** the [xBestIndex] method of a [virtual table] implementation, with P being 10138 ** a copy of the [sqlite3_index_info] object pointer passed into xBestIndex and 10139 ** J being a 0-based index into P->aConstraint[], then this routine 10140 ** attempts to set *V to the value of the right-hand operand of 10141 ** that constraint if the right-hand operand is known. ^If the 10142 ** right-hand operand is not known, then *V is set to a NULL pointer. 10143 ** ^The sqlite3_vtab_rhs_value(P,J,V) interface returns SQLITE_OK if 10144 ** and only if *V is set to a value. ^The sqlite3_vtab_rhs_value(P,J,V) 10145 ** inteface returns SQLITE_NOTFOUND if the right-hand side of the J-th 10146 ** constraint is not available. ^The sqlite3_vtab_rhs_value() interface 10147 ** can return an result code other than SQLITE_OK or SQLITE_NOTFOUND if 10148 ** something goes wrong. 10149 ** 10150 ** The sqlite3_vtab_rhs_value() interface is usually only successful if 10151 ** the right-hand operand of a constraint is a literal value in the original 10152 ** SQL statement. If the right-hand operand is an expression or a reference 10153 ** to some other column or a [host parameter], then sqlite3_vtab_rhs_value() 10154 ** will probably return [SQLITE_NOTFOUND]. 10155 ** 10156 ** ^(Some constraints, such as [SQLITE_INDEX_CONSTRAINT_ISNULL] and 10157 ** [SQLITE_INDEX_CONSTRAINT_ISNOTNULL], have no right-hand operand. For such 10158 ** constraints, sqlite3_vtab_rhs_value() always returns SQLITE_NOTFOUND.)^ 10159 ** 10160 ** ^The [sqlite3_value] object returned in *V is a protected sqlite3_value 10161 ** and remains valid for the duration of the xBestIndex method call. 10162 ** ^When xBestIndex returns, the sqlite3_value object returned by 10163 ** sqlite3_vtab_rhs_value() is automatically deallocated. 10164 ** 10165 ** The "_rhs_" in the name of this routine is an abbreviation for 10166 ** "Right-Hand Side". 10167 */ 10168 SQLITE_API int sqlite3_vtab_rhs_value(sqlite3_index_info*, int, sqlite3_value **ppVal); 10169 10170 /* 10171 ** CAPI3REF: Conflict resolution modes 10172 ** KEYWORDS: {conflict resolution mode} 10173 ** 10174 ** These constants are returned by [sqlite3_vtab_on_conflict()] to 10175 ** inform a [virtual table] implementation what the [ON CONFLICT] mode 10176 ** is for the SQL statement being evaluated. 10177 ** 10178 ** Note that the [SQLITE_IGNORE] constant is also used as a potential 10179 ** return value from the [sqlite3_set_authorizer()] callback and that 10180 ** [SQLITE_ABORT] is also a [result code]. 10181 */ 10182 #define SQLITE_ROLLBACK 1 10183 /* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */ 10184 #define SQLITE_FAIL 3 10185 /* #define SQLITE_ABORT 4 // Also an error code */ 10186 #define SQLITE_REPLACE 5 10187 10188 /* 10189 ** CAPI3REF: Prepared Statement Scan Status Opcodes 10190 ** KEYWORDS: {scanstatus options} 10191 ** 10192 ** The following constants can be used for the T parameter to the 10193 ** [sqlite3_stmt_scanstatus(S,X,T,V)] interface. Each constant designates a 10194 ** different metric for sqlite3_stmt_scanstatus() to return. 10195 ** 10196 ** When the value returned to V is a string, space to hold that string is 10197 ** managed by the prepared statement S and will be automatically freed when 10198 ** S is finalized. 10199 ** 10200 ** Not all values are available for all query elements. When a value is 10201 ** not available, the output variable is set to -1 if the value is numeric, 10202 ** or to NULL if it is a string (SQLITE_SCANSTAT_NAME). 10203 ** 10204 ** <dl> 10205 ** [[SQLITE_SCANSTAT_NLOOP]] <dt>SQLITE_SCANSTAT_NLOOP</dt> 10206 ** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be 10207 ** set to the total number of times that the X-th loop has run.</dd> 10208 ** 10209 ** [[SQLITE_SCANSTAT_NVISIT]] <dt>SQLITE_SCANSTAT_NVISIT</dt> 10210 ** <dd>^The [sqlite3_int64] variable pointed to by the V parameter will be set 10211 ** to the total number of rows examined by all iterations of the X-th loop.</dd> 10212 ** 10213 ** [[SQLITE_SCANSTAT_EST]] <dt>SQLITE_SCANSTAT_EST</dt> 10214 ** <dd>^The "double" variable pointed to by the V parameter will be set to the 10215 ** query planner's estimate for the average number of rows output from each 10216 ** iteration of the X-th loop. If the query planner's estimates was accurate, 10217 ** then this value will approximate the quotient NVISIT/NLOOP and the 10218 ** product of this value for all prior loops with the same SELECTID will 10219 ** be the NLOOP value for the current loop. 10220 ** 10221 ** [[SQLITE_SCANSTAT_NAME]] <dt>SQLITE_SCANSTAT_NAME</dt> 10222 ** <dd>^The "const char *" variable pointed to by the V parameter will be set 10223 ** to a zero-terminated UTF-8 string containing the name of the index or table 10224 ** used for the X-th loop. 10225 ** 10226 ** [[SQLITE_SCANSTAT_EXPLAIN]] <dt>SQLITE_SCANSTAT_EXPLAIN</dt> 10227 ** <dd>^The "const char *" variable pointed to by the V parameter will be set 10228 ** to a zero-terminated UTF-8 string containing the [EXPLAIN QUERY PLAN] 10229 ** description for the X-th loop. 10230 ** 10231 ** [[SQLITE_SCANSTAT_SELECTID]] <dt>SQLITE_SCANSTAT_SELECTID</dt> 10232 ** <dd>^The "int" variable pointed to by the V parameter will be set to the 10233 ** id for the X-th query plan element. The id value is unique within the 10234 ** statement. The select-id is the same value as is output in the first 10235 ** column of an [EXPLAIN QUERY PLAN] query. 10236 ** 10237 ** [[SQLITE_SCANSTAT_PARENTID]] <dt>SQLITE_SCANSTAT_PARENTID</dt> 10238 ** <dd>The "int" variable pointed to by the V parameter will be set to the 10239 ** the id of the parent of the current query element, if applicable, or 10240 ** to zero if the query element has no parent. This is the same value as 10241 ** returned in the second column of an [EXPLAIN QUERY PLAN] query. 10242 ** 10243 ** [[SQLITE_SCANSTAT_NCYCLE]] <dt>SQLITE_SCANSTAT_NCYCLE</dt> 10244 ** <dd>The sqlite3_int64 output value is set to the number of cycles, 10245 ** according to the processor time-stamp counter, that elapsed while the 10246 ** query element was being processed. This value is not available for 10247 ** all query elements - if it is unavailable the output variable is 10248 ** set to -1. 10249 ** </dl> 10250 */ 10251 #define SQLITE_SCANSTAT_NLOOP 0 10252 #define SQLITE_SCANSTAT_NVISIT 1 10253 #define SQLITE_SCANSTAT_EST 2 10254 #define SQLITE_SCANSTAT_NAME 3 10255 #define SQLITE_SCANSTAT_EXPLAIN 4 10256 #define SQLITE_SCANSTAT_SELECTID 5 10257 #define SQLITE_SCANSTAT_PARENTID 6 10258 #define SQLITE_SCANSTAT_NCYCLE 7 10259 10260 /* 10261 ** CAPI3REF: Prepared Statement Scan Status 10262 ** METHOD: sqlite3_stmt 10263 ** 10264 ** These interfaces return information about the predicted and measured 10265 ** performance for pStmt. Advanced applications can use this 10266 ** interface to compare the predicted and the measured performance and 10267 ** issue warnings and/or rerun [ANALYZE] if discrepancies are found. 10268 ** 10269 ** Since this interface is expected to be rarely used, it is only 10270 ** available if SQLite is compiled using the [SQLITE_ENABLE_STMT_SCANSTATUS] 10271 ** compile-time option. 10272 ** 10273 ** The "iScanStatusOp" parameter determines which status information to return. 10274 ** The "iScanStatusOp" must be one of the [scanstatus options] or the behavior 10275 ** of this interface is undefined. ^The requested measurement is written into 10276 ** a variable pointed to by the "pOut" parameter. 10277 ** 10278 ** The "flags" parameter must be passed a mask of flags. At present only 10279 ** one flag is defined - SQLITE_SCANSTAT_COMPLEX. If SQLITE_SCANSTAT_COMPLEX 10280 ** is specified, then status information is available for all elements 10281 ** of a query plan that are reported by "EXPLAIN QUERY PLAN" output. If 10282 ** SQLITE_SCANSTAT_COMPLEX is not specified, then only query plan elements 10283 ** that correspond to query loops (the "SCAN..." and "SEARCH..." elements of 10284 ** the EXPLAIN QUERY PLAN output) are available. Invoking API 10285 ** sqlite3_stmt_scanstatus() is equivalent to calling 10286 ** sqlite3_stmt_scanstatus_v2() with a zeroed flags parameter. 10287 ** 10288 ** Parameter "idx" identifies the specific query element to retrieve statistics 10289 ** for. Query elements are numbered starting from zero. A value of -1 may be 10290 ** to query for statistics regarding the entire query. ^If idx is out of range 10291 ** - less than -1 or greater than or equal to the total number of query 10292 ** elements used to implement the statement - a non-zero value is returned and 10293 ** the variable that pOut points to is unchanged. 10294 ** 10295 ** See also: [sqlite3_stmt_scanstatus_reset()] 10296 */ 10297 SQLITE_API int sqlite3_stmt_scanstatus( 10298 sqlite3_stmt *pStmt, /* Prepared statement for which info desired */ 10299 int idx, /* Index of loop to report on */ 10300 int iScanStatusOp, /* Information desired. SQLITE_SCANSTAT_* */ 10301 void *pOut /* Result written here */ 10302 ); 10303 SQLITE_API int sqlite3_stmt_scanstatus_v2( 10304 sqlite3_stmt *pStmt, /* Prepared statement for which info desired */ 10305 int idx, /* Index of loop to report on */ 10306 int iScanStatusOp, /* Information desired. SQLITE_SCANSTAT_* */ 10307 int flags, /* Mask of flags defined below */ 10308 void *pOut /* Result written here */ 10309 ); 10310 10311 /* 10312 ** CAPI3REF: Prepared Statement Scan Status 10313 ** KEYWORDS: {scan status flags} 10314 */ 10315 #define SQLITE_SCANSTAT_COMPLEX 0x0001 10316 10317 /* 10318 ** CAPI3REF: Zero Scan-Status Counters 10319 ** METHOD: sqlite3_stmt 10320 ** 10321 ** ^Zero all [sqlite3_stmt_scanstatus()] related event counters. 10322 ** 10323 ** This API is only available if the library is built with pre-processor 10324 ** symbol [SQLITE_ENABLE_STMT_SCANSTATUS] defined. 10325 */ 10326 SQLITE_API void sqlite3_stmt_scanstatus_reset(sqlite3_stmt*); 10327 10328 /* 10329 ** CAPI3REF: Flush caches to disk mid-transaction 10330 ** METHOD: sqlite3 10331 ** 10332 ** ^If a write-transaction is open on [database connection] D when the 10333 ** [sqlite3_db_cacheflush(D)] interface invoked, any dirty 10334 ** pages in the pager-cache that are not currently in use are written out 10335 ** to disk. A dirty page may be in use if a database cursor created by an 10336 ** active SQL statement is reading from it, or if it is page 1 of a database 10337 ** file (page 1 is always "in use"). ^The [sqlite3_db_cacheflush(D)] 10338 ** interface flushes caches for all schemas - "main", "temp", and 10339 ** any [attached] databases. 10340 ** 10341 ** ^If this function needs to obtain extra database locks before dirty pages 10342 ** can be flushed to disk, it does so. ^If those locks cannot be obtained 10343 ** immediately and there is a busy-handler callback configured, it is invoked 10344 ** in the usual manner. ^If the required lock still cannot be obtained, then 10345 ** the database is skipped and an attempt made to flush any dirty pages 10346 ** belonging to the next (if any) database. ^If any databases are skipped 10347 ** because locks cannot be obtained, but no other error occurs, this 10348 ** function returns SQLITE_BUSY. 10349 ** 10350 ** ^If any other error occurs while flushing dirty pages to disk (for 10351 ** example an IO error or out-of-memory condition), then processing is 10352 ** abandoned and an SQLite [error code] is returned to the caller immediately. 10353 ** 10354 ** ^Otherwise, if no error occurs, [sqlite3_db_cacheflush()] returns SQLITE_OK. 10355 ** 10356 ** ^This function does not set the database handle error code or message 10357 ** returned by the [sqlite3_errcode()] and [sqlite3_errmsg()] functions. 10358 */ 10359 SQLITE_API int sqlite3_db_cacheflush(sqlite3*); 10360 10361 /* 10362 ** CAPI3REF: The pre-update hook. 10363 ** METHOD: sqlite3 10364 ** 10365 ** ^These interfaces are only available if SQLite is compiled using the 10366 ** [SQLITE_ENABLE_PREUPDATE_HOOK] compile-time option. 10367 ** 10368 ** ^The [sqlite3_preupdate_hook()] interface registers a callback function 10369 ** that is invoked prior to each [INSERT], [UPDATE], and [DELETE] operation 10370 ** on a database table. 10371 ** ^At most one preupdate hook may be registered at a time on a single 10372 ** [database connection]; each call to [sqlite3_preupdate_hook()] overrides 10373 ** the previous setting. 10374 ** ^The preupdate hook is disabled by invoking [sqlite3_preupdate_hook()] 10375 ** with a NULL pointer as the second parameter. 10376 ** ^The third parameter to [sqlite3_preupdate_hook()] is passed through as 10377 ** the first parameter to callbacks. 10378 ** 10379 ** ^The preupdate hook only fires for changes to real database tables; the 10380 ** preupdate hook is not invoked for changes to [virtual tables] or to 10381 ** system tables like sqlite_sequence or sqlite_stat1. 10382 ** 10383 ** ^The second parameter to the preupdate callback is a pointer to 10384 ** the [database connection] that registered the preupdate hook. 10385 ** ^The third parameter to the preupdate callback is one of the constants 10386 ** [SQLITE_INSERT], [SQLITE_DELETE], or [SQLITE_UPDATE] to identify the 10387 ** kind of update operation that is about to occur. 10388 ** ^(The fourth parameter to the preupdate callback is the name of the 10389 ** database within the database connection that is being modified. This 10390 ** will be "main" for the main database or "temp" for TEMP tables or 10391 ** the name given after the AS keyword in the [ATTACH] statement for attached 10392 ** databases.)^ 10393 ** ^The fifth parameter to the preupdate callback is the name of the 10394 ** table that is being modified. 10395 ** 10396 ** For an UPDATE or DELETE operation on a [rowid table], the sixth 10397 ** parameter passed to the preupdate callback is the initial [rowid] of the 10398 ** row being modified or deleted. For an INSERT operation on a rowid table, 10399 ** or any operation on a WITHOUT ROWID table, the value of the sixth 10400 ** parameter is undefined. For an INSERT or UPDATE on a rowid table the 10401 ** seventh parameter is the final rowid value of the row being inserted 10402 ** or updated. The value of the seventh parameter passed to the callback 10403 ** function is not defined for operations on WITHOUT ROWID tables, or for 10404 ** DELETE operations on rowid tables. 10405 ** 10406 ** ^The sqlite3_preupdate_hook(D,C,P) function returns the P argument from 10407 ** the previous call on the same [database connection] D, or NULL for 10408 ** the first call on D. 10409 ** 10410 ** The [sqlite3_preupdate_old()], [sqlite3_preupdate_new()], 10411 ** [sqlite3_preupdate_count()], and [sqlite3_preupdate_depth()] interfaces 10412 ** provide additional information about a preupdate event. These routines 10413 ** may only be called from within a preupdate callback. Invoking any of 10414 ** these routines from outside of a preupdate callback or with a 10415 ** [database connection] pointer that is different from the one supplied 10416 ** to the preupdate callback results in undefined and probably undesirable 10417 ** behavior. 10418 ** 10419 ** ^The [sqlite3_preupdate_count(D)] interface returns the number of columns 10420 ** in the row that is being inserted, updated, or deleted. 10421 ** 10422 ** ^The [sqlite3_preupdate_old(D,N,P)] interface writes into P a pointer to 10423 ** a [protected sqlite3_value] that contains the value of the Nth column of 10424 ** the table row before it is updated. The N parameter must be between 0 10425 ** and one less than the number of columns or the behavior will be 10426 ** undefined. This must only be used within SQLITE_UPDATE and SQLITE_DELETE 10427 ** preupdate callbacks; if it is used by an SQLITE_INSERT callback then the 10428 ** behavior is undefined. The [sqlite3_value] that P points to 10429 ** will be destroyed when the preupdate callback returns. 10430 ** 10431 ** ^The [sqlite3_preupdate_new(D,N,P)] interface writes into P a pointer to 10432 ** a [protected sqlite3_value] that contains the value of the Nth column of 10433 ** the table row after it is updated. The N parameter must be between 0 10434 ** and one less than the number of columns or the behavior will be 10435 ** undefined. This must only be used within SQLITE_INSERT and SQLITE_UPDATE 10436 ** preupdate callbacks; if it is used by an SQLITE_DELETE callback then the 10437 ** behavior is undefined. The [sqlite3_value] that P points to 10438 ** will be destroyed when the preupdate callback returns. 10439 ** 10440 ** ^The [sqlite3_preupdate_depth(D)] interface returns 0 if the preupdate 10441 ** callback was invoked as a result of a direct insert, update, or delete 10442 ** operation; or 1 for inserts, updates, or deletes invoked by top-level 10443 ** triggers; or 2 for changes resulting from triggers called by top-level 10444 ** triggers; and so forth. 10445 ** 10446 ** When the [sqlite3_blob_write()] API is used to update a blob column, 10447 ** the pre-update hook is invoked with SQLITE_DELETE. This is because the 10448 ** in this case the new values are not available. In this case, when a 10449 ** callback made with op==SQLITE_DELETE is actually a write using the 10450 ** sqlite3_blob_write() API, the [sqlite3_preupdate_blobwrite()] returns 10451 ** the index of the column being written. In other cases, where the 10452 ** pre-update hook is being invoked for some other reason, including a 10453 ** regular DELETE, sqlite3_preupdate_blobwrite() returns -1. 10454 ** 10455 ** See also: [sqlite3_update_hook()] 10456 */ 10457 #if defined(SQLITE_ENABLE_PREUPDATE_HOOK) 10458 SQLITE_API void *sqlite3_preupdate_hook( 10459 sqlite3 *db, 10460 void(*xPreUpdate)( 10461 void *pCtx, /* Copy of third arg to preupdate_hook() */ 10462 sqlite3 *db, /* Database handle */ 10463 int op, /* SQLITE_UPDATE, DELETE or INSERT */ 10464 char const *zDb, /* Database name */ 10465 char const *zName, /* Table name */ 10466 sqlite3_int64 iKey1, /* Rowid of row about to be deleted/updated */ 10467 sqlite3_int64 iKey2 /* New rowid value (for a rowid UPDATE) */ 10468 ), 10469 void* 10470 ); 10471 SQLITE_API int sqlite3_preupdate_old(sqlite3 *, int, sqlite3_value **); 10472 SQLITE_API int sqlite3_preupdate_count(sqlite3 *); 10473 SQLITE_API int sqlite3_preupdate_depth(sqlite3 *); 10474 SQLITE_API int sqlite3_preupdate_new(sqlite3 *, int, sqlite3_value **); 10475 SQLITE_API int sqlite3_preupdate_blobwrite(sqlite3 *); 10476 #endif 10477 10478 /* 10479 ** CAPI3REF: Low-level system error code 10480 ** METHOD: sqlite3 10481 ** 10482 ** ^Attempt to return the underlying operating system error code or error 10483 ** number that caused the most recent I/O error or failure to open a file. 10484 ** The return value is OS-dependent. For example, on unix systems, after 10485 ** [sqlite3_open_v2()] returns [SQLITE_CANTOPEN], this interface could be 10486 ** called to get back the underlying "errno" that caused the problem, such 10487 ** as ENOSPC, EAUTH, EISDIR, and so forth. 10488 */ 10489 SQLITE_API int sqlite3_system_errno(sqlite3*); 10490 10491 /* 10492 ** CAPI3REF: Database Snapshot 10493 ** KEYWORDS: {snapshot} {sqlite3_snapshot} 10494 ** 10495 ** An instance of the snapshot object records the state of a [WAL mode] 10496 ** database for some specific point in history. 10497 ** 10498 ** In [WAL mode], multiple [database connections] that are open on the 10499 ** same database file can each be reading a different historical version 10500 ** of the database file. When a [database connection] begins a read 10501 ** transaction, that connection sees an unchanging copy of the database 10502 ** as it existed for the point in time when the transaction first started. 10503 ** Subsequent changes to the database from other connections are not seen 10504 ** by the reader until a new read transaction is started. 10505 ** 10506 ** The sqlite3_snapshot object records state information about an historical 10507 ** version of the database file so that it is possible to later open a new read 10508 ** transaction that sees that historical version of the database rather than 10509 ** the most recent version. 10510 */ 10511 typedef struct sqlite3_snapshot { 10512 unsigned char hidden[48]; 10513 } sqlite3_snapshot; 10514 10515 /* 10516 ** CAPI3REF: Record A Database Snapshot 10517 ** CONSTRUCTOR: sqlite3_snapshot 10518 ** 10519 ** ^The [sqlite3_snapshot_get(D,S,P)] interface attempts to make a 10520 ** new [sqlite3_snapshot] object that records the current state of 10521 ** schema S in database connection D. ^On success, the 10522 ** [sqlite3_snapshot_get(D,S,P)] interface writes a pointer to the newly 10523 ** created [sqlite3_snapshot] object into *P and returns SQLITE_OK. 10524 ** If there is not already a read-transaction open on schema S when 10525 ** this function is called, one is opened automatically. 10526 ** 10527 ** The following must be true for this function to succeed. If any of 10528 ** the following statements are false when sqlite3_snapshot_get() is 10529 ** called, SQLITE_ERROR is returned. The final value of *P is undefined 10530 ** in this case. 10531 ** 10532 ** <ul> 10533 ** <li> The database handle must not be in [autocommit mode]. 10534 ** 10535 ** <li> Schema S of [database connection] D must be a [WAL mode] database. 10536 ** 10537 ** <li> There must not be a write transaction open on schema S of database 10538 ** connection D. 10539 ** 10540 ** <li> One or more transactions must have been written to the current wal 10541 ** file since it was created on disk (by any connection). This means 10542 ** that a snapshot cannot be taken on a wal mode database with no wal 10543 ** file immediately after it is first opened. At least one transaction 10544 ** must be written to it first. 10545 ** </ul> 10546 ** 10547 ** This function may also return SQLITE_NOMEM. If it is called with the 10548 ** database handle in autocommit mode but fails for some other reason, 10549 ** whether or not a read transaction is opened on schema S is undefined. 10550 ** 10551 ** The [sqlite3_snapshot] object returned from a successful call to 10552 ** [sqlite3_snapshot_get()] must be freed using [sqlite3_snapshot_free()] 10553 ** to avoid a memory leak. 10554 ** 10555 ** The [sqlite3_snapshot_get()] interface is only available when the 10556 ** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. 10557 */ 10558 SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_get( 10559 sqlite3 *db, 10560 const char *zSchema, 10561 sqlite3_snapshot **ppSnapshot 10562 ); 10563 10564 /* 10565 ** CAPI3REF: Start a read transaction on an historical snapshot 10566 ** METHOD: sqlite3_snapshot 10567 ** 10568 ** ^The [sqlite3_snapshot_open(D,S,P)] interface either starts a new read 10569 ** transaction or upgrades an existing one for schema S of 10570 ** [database connection] D such that the read transaction refers to 10571 ** historical [snapshot] P, rather than the most recent change to the 10572 ** database. ^The [sqlite3_snapshot_open()] interface returns SQLITE_OK 10573 ** on success or an appropriate [error code] if it fails. 10574 ** 10575 ** ^In order to succeed, the database connection must not be in 10576 ** [autocommit mode] when [sqlite3_snapshot_open(D,S,P)] is called. If there 10577 ** is already a read transaction open on schema S, then the database handle 10578 ** must have no active statements (SELECT statements that have been passed 10579 ** to sqlite3_step() but not sqlite3_reset() or sqlite3_finalize()). 10580 ** SQLITE_ERROR is returned if either of these conditions is violated, or 10581 ** if schema S does not exist, or if the snapshot object is invalid. 10582 ** 10583 ** ^A call to sqlite3_snapshot_open() will fail to open if the specified 10584 ** snapshot has been overwritten by a [checkpoint]. In this case 10585 ** SQLITE_ERROR_SNAPSHOT is returned. 10586 ** 10587 ** If there is already a read transaction open when this function is 10588 ** invoked, then the same read transaction remains open (on the same 10589 ** database snapshot) if SQLITE_ERROR, SQLITE_BUSY or SQLITE_ERROR_SNAPSHOT 10590 ** is returned. If another error code - for example SQLITE_PROTOCOL or an 10591 ** SQLITE_IOERR error code - is returned, then the final state of the 10592 ** read transaction is undefined. If SQLITE_OK is returned, then the 10593 ** read transaction is now open on database snapshot P. 10594 ** 10595 ** ^(A call to [sqlite3_snapshot_open(D,S,P)] will fail if the 10596 ** database connection D does not know that the database file for 10597 ** schema S is in [WAL mode]. A database connection might not know 10598 ** that the database file is in [WAL mode] if there has been no prior 10599 ** I/O on that database connection, or if the database entered [WAL mode] 10600 ** after the most recent I/O on the database connection.)^ 10601 ** (Hint: Run "[PRAGMA application_id]" against a newly opened 10602 ** database connection in order to make it ready to use snapshots.) 10603 ** 10604 ** The [sqlite3_snapshot_open()] interface is only available when the 10605 ** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. 10606 */ 10607 SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_open( 10608 sqlite3 *db, 10609 const char *zSchema, 10610 sqlite3_snapshot *pSnapshot 10611 ); 10612 10613 /* 10614 ** CAPI3REF: Destroy a snapshot 10615 ** DESTRUCTOR: sqlite3_snapshot 10616 ** 10617 ** ^The [sqlite3_snapshot_free(P)] interface destroys [sqlite3_snapshot] P. 10618 ** The application must eventually free every [sqlite3_snapshot] object 10619 ** using this routine to avoid a memory leak. 10620 ** 10621 ** The [sqlite3_snapshot_free()] interface is only available when the 10622 ** [SQLITE_ENABLE_SNAPSHOT] compile-time option is used. 10623 */ 10624 SQLITE_API SQLITE_EXPERIMENTAL void sqlite3_snapshot_free(sqlite3_snapshot*); 10625 10626 /* 10627 ** CAPI3REF: Compare the ages of two snapshot handles. 10628 ** METHOD: sqlite3_snapshot 10629 ** 10630 ** The sqlite3_snapshot_cmp(P1, P2) interface is used to compare the ages 10631 ** of two valid snapshot handles. 10632 ** 10633 ** If the two snapshot handles are not associated with the same database 10634 ** file, the result of the comparison is undefined. 10635 ** 10636 ** Additionally, the result of the comparison is only valid if both of the 10637 ** snapshot handles were obtained by calling sqlite3_snapshot_get() since the 10638 ** last time the wal file was deleted. The wal file is deleted when the 10639 ** database is changed back to rollback mode or when the number of database 10640 ** clients drops to zero. If either snapshot handle was obtained before the 10641 ** wal file was last deleted, the value returned by this function 10642 ** is undefined. 10643 ** 10644 ** Otherwise, this API returns a negative value if P1 refers to an older 10645 ** snapshot than P2, zero if the two handles refer to the same database 10646 ** snapshot, and a positive value if P1 is a newer snapshot than P2. 10647 ** 10648 ** This interface is only available if SQLite is compiled with the 10649 ** [SQLITE_ENABLE_SNAPSHOT] option. 10650 */ 10651 SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_cmp( 10652 sqlite3_snapshot *p1, 10653 sqlite3_snapshot *p2 10654 ); 10655 10656 /* 10657 ** CAPI3REF: Recover snapshots from a wal file 10658 ** METHOD: sqlite3_snapshot 10659 ** 10660 ** If a [WAL file] remains on disk after all database connections close 10661 ** (either through the use of the [SQLITE_FCNTL_PERSIST_WAL] [file control] 10662 ** or because the last process to have the database opened exited without 10663 ** calling [sqlite3_close()]) and a new connection is subsequently opened 10664 ** on that database and [WAL file], the [sqlite3_snapshot_open()] interface 10665 ** will only be able to open the last transaction added to the WAL file 10666 ** even though the WAL file contains other valid transactions. 10667 ** 10668 ** This function attempts to scan the WAL file associated with database zDb 10669 ** of database handle db and make all valid snapshots available to 10670 ** sqlite3_snapshot_open(). It is an error if there is already a read 10671 ** transaction open on the database, or if the database is not a WAL mode 10672 ** database. 10673 ** 10674 ** SQLITE_OK is returned if successful, or an SQLite error code otherwise. 10675 ** 10676 ** This interface is only available if SQLite is compiled with the 10677 ** [SQLITE_ENABLE_SNAPSHOT] option. 10678 */ 10679 SQLITE_API SQLITE_EXPERIMENTAL int sqlite3_snapshot_recover(sqlite3 *db, const char *zDb); 10680 10681 /* 10682 ** CAPI3REF: Serialize a database 10683 ** 10684 ** The sqlite3_serialize(D,S,P,F) interface returns a pointer to memory 10685 ** that is a serialization of the S database on [database connection] D. 10686 ** If P is not a NULL pointer, then the size of the database in bytes 10687 ** is written into *P. 10688 ** 10689 ** For an ordinary on-disk database file, the serialization is just a 10690 ** copy of the disk file. For an in-memory database or a "TEMP" database, 10691 ** the serialization is the same sequence of bytes which would be written 10692 ** to disk if that database where backed up to disk. 10693 ** 10694 ** The usual case is that sqlite3_serialize() copies the serialization of 10695 ** the database into memory obtained from [sqlite3_malloc64()] and returns 10696 ** a pointer to that memory. The caller is responsible for freeing the 10697 ** returned value to avoid a memory leak. However, if the F argument 10698 ** contains the SQLITE_SERIALIZE_NOCOPY bit, then no memory allocations 10699 ** are made, and the sqlite3_serialize() function will return a pointer 10700 ** to the contiguous memory representation of the database that SQLite 10701 ** is currently using for that database, or NULL if the no such contiguous 10702 ** memory representation of the database exists. A contiguous memory 10703 ** representation of the database will usually only exist if there has 10704 ** been a prior call to [sqlite3_deserialize(D,S,...)] with the same 10705 ** values of D and S. 10706 ** The size of the database is written into *P even if the 10707 ** SQLITE_SERIALIZE_NOCOPY bit is set but no contiguous copy 10708 ** of the database exists. 10709 ** 10710 ** After the call, if the SQLITE_SERIALIZE_NOCOPY bit had been set, 10711 ** the returned buffer content will remain accessible and unchanged 10712 ** until either the next write operation on the connection or when 10713 ** the connection is closed, and applications must not modify the 10714 ** buffer. If the bit had been clear, the returned buffer will not 10715 ** be accessed by SQLite after the call. 10716 ** 10717 ** A call to sqlite3_serialize(D,S,P,F) might return NULL even if the 10718 ** SQLITE_SERIALIZE_NOCOPY bit is omitted from argument F if a memory 10719 ** allocation error occurs. 10720 ** 10721 ** This interface is omitted if SQLite is compiled with the 10722 ** [SQLITE_OMIT_DESERIALIZE] option. 10723 */ 10724 SQLITE_API unsigned char *sqlite3_serialize( 10725 sqlite3 *db, /* The database connection */ 10726 const char *zSchema, /* Which DB to serialize. ex: "main", "temp", ... */ 10727 sqlite3_int64 *piSize, /* Write size of the DB here, if not NULL */ 10728 unsigned int mFlags /* Zero or more SQLITE_SERIALIZE_* flags */ 10729 ); 10730 10731 /* 10732 ** CAPI3REF: Flags for sqlite3_serialize 10733 ** 10734 ** Zero or more of the following constants can be OR-ed together for 10735 ** the F argument to [sqlite3_serialize(D,S,P,F)]. 10736 ** 10737 ** SQLITE_SERIALIZE_NOCOPY means that [sqlite3_serialize()] will return 10738 ** a pointer to contiguous in-memory database that it is currently using, 10739 ** without making a copy of the database. If SQLite is not currently using 10740 ** a contiguous in-memory database, then this option causes 10741 ** [sqlite3_serialize()] to return a NULL pointer. SQLite will only be 10742 ** using a contiguous in-memory database if it has been initialized by a 10743 ** prior call to [sqlite3_deserialize()]. 10744 */ 10745 #define SQLITE_SERIALIZE_NOCOPY 0x001 /* Do no memory allocations */ 10746 10747 /* 10748 ** CAPI3REF: Deserialize a database 10749 ** 10750 ** The sqlite3_deserialize(D,S,P,N,M,F) interface causes the 10751 ** [database connection] D to disconnect from database S and then 10752 ** reopen S as an in-memory database based on the serialization contained 10753 ** in P. The serialized database P is N bytes in size. M is the size of 10754 ** the buffer P, which might be larger than N. If M is larger than N, and 10755 ** the SQLITE_DESERIALIZE_READONLY bit is not set in F, then SQLite is 10756 ** permitted to add content to the in-memory database as long as the total 10757 ** size does not exceed M bytes. 10758 ** 10759 ** If the SQLITE_DESERIALIZE_FREEONCLOSE bit is set in F, then SQLite will 10760 ** invoke sqlite3_free() on the serialization buffer when the database 10761 ** connection closes. If the SQLITE_DESERIALIZE_RESIZEABLE bit is set, then 10762 ** SQLite will try to increase the buffer size using sqlite3_realloc64() 10763 ** if writes on the database cause it to grow larger than M bytes. 10764 ** 10765 ** Applications must not modify the buffer P or invalidate it before 10766 ** the database connection D is closed. 10767 ** 10768 ** The sqlite3_deserialize() interface will fail with SQLITE_BUSY if the 10769 ** database is currently in a read transaction or is involved in a backup 10770 ** operation. 10771 ** 10772 ** It is not possible to deserialized into the TEMP database. If the 10773 ** S argument to sqlite3_deserialize(D,S,P,N,M,F) is "temp" then the 10774 ** function returns SQLITE_ERROR. 10775 ** 10776 ** The deserialized database should not be in [WAL mode]. If the database 10777 ** is in WAL mode, then any attempt to use the database file will result 10778 ** in an [SQLITE_CANTOPEN] error. The application can set the 10779 ** [file format version numbers] (bytes 18 and 19) of the input database P 10780 ** to 0x01 prior to invoking sqlite3_deserialize(D,S,P,N,M,F) to force the 10781 ** database file into rollback mode and work around this limitation. 10782 ** 10783 ** If sqlite3_deserialize(D,S,P,N,M,F) fails for any reason and if the 10784 ** SQLITE_DESERIALIZE_FREEONCLOSE bit is set in argument F, then 10785 ** [sqlite3_free()] is invoked on argument P prior to returning. 10786 ** 10787 ** This interface is omitted if SQLite is compiled with the 10788 ** [SQLITE_OMIT_DESERIALIZE] option. 10789 */ 10790 SQLITE_API int sqlite3_deserialize( 10791 sqlite3 *db, /* The database connection */ 10792 const char *zSchema, /* Which DB to reopen with the deserialization */ 10793 unsigned char *pData, /* The serialized database content */ 10794 sqlite3_int64 szDb, /* Number bytes in the deserialization */ 10795 sqlite3_int64 szBuf, /* Total size of buffer pData[] */ 10796 unsigned mFlags /* Zero or more SQLITE_DESERIALIZE_* flags */ 10797 ); 10798 10799 /* 10800 ** CAPI3REF: Flags for sqlite3_deserialize() 10801 ** 10802 ** The following are allowed values for 6th argument (the F argument) to 10803 ** the [sqlite3_deserialize(D,S,P,N,M,F)] interface. 10804 ** 10805 ** The SQLITE_DESERIALIZE_FREEONCLOSE means that the database serialization 10806 ** in the P argument is held in memory obtained from [sqlite3_malloc64()] 10807 ** and that SQLite should take ownership of this memory and automatically 10808 ** free it when it has finished using it. Without this flag, the caller 10809 ** is responsible for freeing any dynamically allocated memory. 10810 ** 10811 ** The SQLITE_DESERIALIZE_RESIZEABLE flag means that SQLite is allowed to 10812 ** grow the size of the database using calls to [sqlite3_realloc64()]. This 10813 ** flag should only be used if SQLITE_DESERIALIZE_FREEONCLOSE is also used. 10814 ** Without this flag, the deserialized database cannot increase in size beyond 10815 ** the number of bytes specified by the M parameter. 10816 ** 10817 ** The SQLITE_DESERIALIZE_READONLY flag means that the deserialized database 10818 ** should be treated as read-only. 10819 */ 10820 #define SQLITE_DESERIALIZE_FREEONCLOSE 1 /* Call sqlite3_free() on close */ 10821 #define SQLITE_DESERIALIZE_RESIZEABLE 2 /* Resize using sqlite3_realloc64() */ 10822 #define SQLITE_DESERIALIZE_READONLY 4 /* Database is read-only */ 10823 10824 /* 10825 ** Undo the hack that converts floating point types to integer for 10826 ** builds on processors without floating point support. 10827 */ 10828 #ifdef SQLITE_OMIT_FLOATING_POINT 10829 # undef double 10830 #endif 10831 10832 #if defined(__wasi__) 10833 # undef SQLITE_WASI 10834 # define SQLITE_WASI 1 10835 # undef SQLITE_OMIT_WAL 10836 # define SQLITE_OMIT_WAL 1/* because it requires shared memory APIs */ 10837 # ifndef SQLITE_OMIT_LOAD_EXTENSION 10838 # define SQLITE_OMIT_LOAD_EXTENSION 10839 # endif 10840 # ifndef SQLITE_THREADSAFE 10841 # define SQLITE_THREADSAFE 0 10842 # endif 10843 #endif 10844 10845 #ifdef __cplusplus 10846 } /* End of the 'extern "C"' block */ 10847 #endif 10848 #endif /* SQLITE3_H */ 10849 10850 /******** Begin file sqlite3rtree.h *********/ 10851 /* 10852 ** 2010 August 30 10853 ** 10854 ** The author disclaims copyright to this source code. In place of 10855 ** a legal notice, here is a blessing: 10856 ** 10857 ** May you do good and not evil. 10858 ** May you find forgiveness for yourself and forgive others. 10859 ** May you share freely, never taking more than you give. 10860 ** 10861 ************************************************************************* 10862 */ 10863 10864 #ifndef _SQLITE3RTREE_H_ 10865 #define _SQLITE3RTREE_H_ 10866 10867 10868 #ifdef __cplusplus 10869 extern "C" { 10870 #endif 10871 10872 typedef struct sqlite3_rtree_geometry sqlite3_rtree_geometry; 10873 typedef struct sqlite3_rtree_query_info sqlite3_rtree_query_info; 10874 10875 /* The double-precision datatype used by RTree depends on the 10876 ** SQLITE_RTREE_INT_ONLY compile-time option. 10877 */ 10878 #ifdef SQLITE_RTREE_INT_ONLY 10879 typedef sqlite3_int64 sqlite3_rtree_dbl; 10880 #else 10881 typedef double sqlite3_rtree_dbl; 10882 #endif 10883 10884 /* 10885 ** Register a geometry callback named zGeom that can be used as part of an 10886 ** R-Tree geometry query as follows: 10887 ** 10888 ** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zGeom(... params ...) 10889 */ 10890 SQLITE_API int sqlite3_rtree_geometry_callback( 10891 sqlite3 *db, 10892 const char *zGeom, 10893 int (*xGeom)(sqlite3_rtree_geometry*, int, sqlite3_rtree_dbl*,int*), 10894 void *pContext 10895 ); 10896 10897 10898 /* 10899 ** A pointer to a structure of the following type is passed as the first 10900 ** argument to callbacks registered using rtree_geometry_callback(). 10901 */ 10902 struct sqlite3_rtree_geometry { 10903 void *pContext; /* Copy of pContext passed to s_r_g_c() */ 10904 int nParam; /* Size of array aParam[] */ 10905 sqlite3_rtree_dbl *aParam; /* Parameters passed to SQL geom function */ 10906 void *pUser; /* Callback implementation user data */ 10907 void (*xDelUser)(void *); /* Called by SQLite to clean up pUser */ 10908 }; 10909 10910 /* 10911 ** Register a 2nd-generation geometry callback named zScore that can be 10912 ** used as part of an R-Tree geometry query as follows: 10913 ** 10914 ** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zQueryFunc(... params ...) 10915 */ 10916 SQLITE_API int sqlite3_rtree_query_callback( 10917 sqlite3 *db, 10918 const char *zQueryFunc, 10919 int (*xQueryFunc)(sqlite3_rtree_query_info*), 10920 void *pContext, 10921 void (*xDestructor)(void*) 10922 ); 10923 10924 10925 /* 10926 ** A pointer to a structure of the following type is passed as the 10927 ** argument to scored geometry callback registered using 10928 ** sqlite3_rtree_query_callback(). 10929 ** 10930 ** Note that the first 5 fields of this structure are identical to 10931 ** sqlite3_rtree_geometry. This structure is a subclass of 10932 ** sqlite3_rtree_geometry. 10933 */ 10934 struct sqlite3_rtree_query_info { 10935 void *pContext; /* pContext from when function registered */ 10936 int nParam; /* Number of function parameters */ 10937 sqlite3_rtree_dbl *aParam; /* value of function parameters */ 10938 void *pUser; /* callback can use this, if desired */ 10939 void (*xDelUser)(void*); /* function to free pUser */ 10940 sqlite3_rtree_dbl *aCoord; /* Coordinates of node or entry to check */ 10941 unsigned int *anQueue; /* Number of pending entries in the queue */ 10942 int nCoord; /* Number of coordinates */ 10943 int iLevel; /* Level of current node or entry */ 10944 int mxLevel; /* The largest iLevel value in the tree */ 10945 sqlite3_int64 iRowid; /* Rowid for current entry */ 10946 sqlite3_rtree_dbl rParentScore; /* Score of parent node */ 10947 int eParentWithin; /* Visibility of parent node */ 10948 int eWithin; /* OUT: Visibility */ 10949 sqlite3_rtree_dbl rScore; /* OUT: Write the score here */ 10950 /* The following fields are only available in 3.8.11 and later */ 10951 sqlite3_value **apSqlParam; /* Original SQL values of parameters */ 10952 }; 10953 10954 /* 10955 ** Allowed values for sqlite3_rtree_query.eWithin and .eParentWithin. 10956 */ 10957 #define NOT_WITHIN 0 /* Object completely outside of query region */ 10958 #define PARTLY_WITHIN 1 /* Object partially overlaps query region */ 10959 #define FULLY_WITHIN 2 /* Object fully contained within query region */ 10960 10961 10962 #ifdef __cplusplus 10963 } /* end of the 'extern "C"' block */ 10964 #endif 10965 10966 #endif /* ifndef _SQLITE3RTREE_H_ */ 10967 10968 /******** End of sqlite3rtree.h *********/ 10969 /******** Begin file sqlite3session.h *********/ 10970 10971 #if !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) 10972 #define __SQLITESESSION_H_ 1 10973 10974 /* 10975 ** Make sure we can call this stuff from C++. 10976 */ 10977 #ifdef __cplusplus 10978 extern "C" { 10979 #endif 10980 10981 10982 /* 10983 ** CAPI3REF: Session Object Handle 10984 ** 10985 ** An instance of this object is a [session] that can be used to 10986 ** record changes to a database. 10987 */ 10988 typedef struct sqlite3_session sqlite3_session; 10989 10990 /* 10991 ** CAPI3REF: Changeset Iterator Handle 10992 ** 10993 ** An instance of this object acts as a cursor for iterating 10994 ** over the elements of a [changeset] or [patchset]. 10995 */ 10996 typedef struct sqlite3_changeset_iter sqlite3_changeset_iter; 10997 10998 /* 10999 ** CAPI3REF: Create A New Session Object 11000 ** CONSTRUCTOR: sqlite3_session 11001 ** 11002 ** Create a new session object attached to database handle db. If successful, 11003 ** a pointer to the new object is written to *ppSession and SQLITE_OK is 11004 ** returned. If an error occurs, *ppSession is set to NULL and an SQLite 11005 ** error code (e.g. SQLITE_NOMEM) is returned. 11006 ** 11007 ** It is possible to create multiple session objects attached to a single 11008 ** database handle. 11009 ** 11010 ** Session objects created using this function should be deleted using the 11011 ** [sqlite3session_delete()] function before the database handle that they 11012 ** are attached to is itself closed. If the database handle is closed before 11013 ** the session object is deleted, then the results of calling any session 11014 ** module function, including [sqlite3session_delete()] on the session object 11015 ** are undefined. 11016 ** 11017 ** Because the session module uses the [sqlite3_preupdate_hook()] API, it 11018 ** is not possible for an application to register a pre-update hook on a 11019 ** database handle that has one or more session objects attached. Nor is 11020 ** it possible to create a session object attached to a database handle for 11021 ** which a pre-update hook is already defined. The results of attempting 11022 ** either of these things are undefined. 11023 ** 11024 ** The session object will be used to create changesets for tables in 11025 ** database zDb, where zDb is either "main", or "temp", or the name of an 11026 ** attached database. It is not an error if database zDb is not attached 11027 ** to the database when the session object is created. 11028 */ 11029 SQLITE_API int sqlite3session_create( 11030 sqlite3 *db, /* Database handle */ 11031 const char *zDb, /* Name of db (e.g. "main") */ 11032 sqlite3_session **ppSession /* OUT: New session object */ 11033 ); 11034 11035 /* 11036 ** CAPI3REF: Delete A Session Object 11037 ** DESTRUCTOR: sqlite3_session 11038 ** 11039 ** Delete a session object previously allocated using 11040 ** [sqlite3session_create()]. Once a session object has been deleted, the 11041 ** results of attempting to use pSession with any other session module 11042 ** function are undefined. 11043 ** 11044 ** Session objects must be deleted before the database handle to which they 11045 ** are attached is closed. Refer to the documentation for 11046 ** [sqlite3session_create()] for details. 11047 */ 11048 SQLITE_API void sqlite3session_delete(sqlite3_session *pSession); 11049 11050 /* 11051 ** CAPI3REF: Configure a Session Object 11052 ** METHOD: sqlite3_session 11053 ** 11054 ** This method is used to configure a session object after it has been 11055 ** created. At present the only valid values for the second parameter are 11056 ** [SQLITE_SESSION_OBJCONFIG_SIZE] and [SQLITE_SESSION_OBJCONFIG_ROWID]. 11057 ** 11058 */ 11059 SQLITE_API int sqlite3session_object_config(sqlite3_session*, int op, void *pArg); 11060 11061 /* 11062 ** CAPI3REF: Options for sqlite3session_object_config 11063 ** 11064 ** The following values may passed as the the 2nd parameter to 11065 ** sqlite3session_object_config(). 11066 ** 11067 ** <dt>SQLITE_SESSION_OBJCONFIG_SIZE <dd> 11068 ** This option is used to set, clear or query the flag that enables 11069 ** the [sqlite3session_changeset_size()] API. Because it imposes some 11070 ** computational overhead, this API is disabled by default. Argument 11071 ** pArg must point to a value of type (int). If the value is initially 11072 ** 0, then the sqlite3session_changeset_size() API is disabled. If it 11073 ** is greater than 0, then the same API is enabled. Or, if the initial 11074 ** value is less than zero, no change is made. In all cases the (int) 11075 ** variable is set to 1 if the sqlite3session_changeset_size() API is 11076 ** enabled following the current call, or 0 otherwise. 11077 ** 11078 ** It is an error (SQLITE_MISUSE) to attempt to modify this setting after 11079 ** the first table has been attached to the session object. 11080 ** 11081 ** <dt>SQLITE_SESSION_OBJCONFIG_ROWID <dd> 11082 ** This option is used to set, clear or query the flag that enables 11083 ** collection of data for tables with no explicit PRIMARY KEY. 11084 ** 11085 ** Normally, tables with no explicit PRIMARY KEY are simply ignored 11086 ** by the sessions module. However, if this flag is set, it behaves 11087 ** as if such tables have a column "_rowid_ INTEGER PRIMARY KEY" inserted 11088 ** as their leftmost columns. 11089 ** 11090 ** It is an error (SQLITE_MISUSE) to attempt to modify this setting after 11091 ** the first table has been attached to the session object. 11092 */ 11093 #define SQLITE_SESSION_OBJCONFIG_SIZE 1 11094 #define SQLITE_SESSION_OBJCONFIG_ROWID 2 11095 11096 /* 11097 ** CAPI3REF: Enable Or Disable A Session Object 11098 ** METHOD: sqlite3_session 11099 ** 11100 ** Enable or disable the recording of changes by a session object. When 11101 ** enabled, a session object records changes made to the database. When 11102 ** disabled - it does not. A newly created session object is enabled. 11103 ** Refer to the documentation for [sqlite3session_changeset()] for further 11104 ** details regarding how enabling and disabling a session object affects 11105 ** the eventual changesets. 11106 ** 11107 ** Passing zero to this function disables the session. Passing a value 11108 ** greater than zero enables it. Passing a value less than zero is a 11109 ** no-op, and may be used to query the current state of the session. 11110 ** 11111 ** The return value indicates the final state of the session object: 0 if 11112 ** the session is disabled, or 1 if it is enabled. 11113 */ 11114 SQLITE_API int sqlite3session_enable(sqlite3_session *pSession, int bEnable); 11115 11116 /* 11117 ** CAPI3REF: Set Or Clear the Indirect Change Flag 11118 ** METHOD: sqlite3_session 11119 ** 11120 ** Each change recorded by a session object is marked as either direct or 11121 ** indirect. A change is marked as indirect if either: 11122 ** 11123 ** <ul> 11124 ** <li> The session object "indirect" flag is set when the change is 11125 ** made, or 11126 ** <li> The change is made by an SQL trigger or foreign key action 11127 ** instead of directly as a result of a users SQL statement. 11128 ** </ul> 11129 ** 11130 ** If a single row is affected by more than one operation within a session, 11131 ** then the change is considered indirect if all operations meet the criteria 11132 ** for an indirect change above, or direct otherwise. 11133 ** 11134 ** This function is used to set, clear or query the session object indirect 11135 ** flag. If the second argument passed to this function is zero, then the 11136 ** indirect flag is cleared. If it is greater than zero, the indirect flag 11137 ** is set. Passing a value less than zero does not modify the current value 11138 ** of the indirect flag, and may be used to query the current state of the 11139 ** indirect flag for the specified session object. 11140 ** 11141 ** The return value indicates the final state of the indirect flag: 0 if 11142 ** it is clear, or 1 if it is set. 11143 */ 11144 SQLITE_API int sqlite3session_indirect(sqlite3_session *pSession, int bIndirect); 11145 11146 /* 11147 ** CAPI3REF: Attach A Table To A Session Object 11148 ** METHOD: sqlite3_session 11149 ** 11150 ** If argument zTab is not NULL, then it is the name of a table to attach 11151 ** to the session object passed as the first argument. All subsequent changes 11152 ** made to the table while the session object is enabled will be recorded. See 11153 ** documentation for [sqlite3session_changeset()] for further details. 11154 ** 11155 ** Or, if argument zTab is NULL, then changes are recorded for all tables 11156 ** in the database. If additional tables are added to the database (by 11157 ** executing "CREATE TABLE" statements) after this call is made, changes for 11158 ** the new tables are also recorded. 11159 ** 11160 ** Changes can only be recorded for tables that have a PRIMARY KEY explicitly 11161 ** defined as part of their CREATE TABLE statement. It does not matter if the 11162 ** PRIMARY KEY is an "INTEGER PRIMARY KEY" (rowid alias) or not. The PRIMARY 11163 ** KEY may consist of a single column, or may be a composite key. 11164 ** 11165 ** It is not an error if the named table does not exist in the database. Nor 11166 ** is it an error if the named table does not have a PRIMARY KEY. However, 11167 ** no changes will be recorded in either of these scenarios. 11168 ** 11169 ** Changes are not recorded for individual rows that have NULL values stored 11170 ** in one or more of their PRIMARY KEY columns. 11171 ** 11172 ** SQLITE_OK is returned if the call completes without error. Or, if an error 11173 ** occurs, an SQLite error code (e.g. SQLITE_NOMEM) is returned. 11174 ** 11175 ** <h3>Special sqlite_stat1 Handling</h3> 11176 ** 11177 ** As of SQLite version 3.22.0, the "sqlite_stat1" table is an exception to 11178 ** some of the rules above. In SQLite, the schema of sqlite_stat1 is: 11179 ** <pre> 11180 ** CREATE TABLE sqlite_stat1(tbl,idx,stat) 11181 ** </pre> 11182 ** 11183 ** Even though sqlite_stat1 does not have a PRIMARY KEY, changes are 11184 ** recorded for it as if the PRIMARY KEY is (tbl,idx). Additionally, changes 11185 ** are recorded for rows for which (idx IS NULL) is true. However, for such 11186 ** rows a zero-length blob (SQL value X'') is stored in the changeset or 11187 ** patchset instead of a NULL value. This allows such changesets to be 11188 ** manipulated by legacy implementations of sqlite3changeset_invert(), 11189 ** concat() and similar. 11190 ** 11191 ** The sqlite3changeset_apply() function automatically converts the 11192 ** zero-length blob back to a NULL value when updating the sqlite_stat1 11193 ** table. However, if the application calls sqlite3changeset_new(), 11194 ** sqlite3changeset_old() or sqlite3changeset_conflict on a changeset 11195 ** iterator directly (including on a changeset iterator passed to a 11196 ** conflict-handler callback) then the X'' value is returned. The application 11197 ** must translate X'' to NULL itself if required. 11198 ** 11199 ** Legacy (older than 3.22.0) versions of the sessions module cannot capture 11200 ** changes made to the sqlite_stat1 table. Legacy versions of the 11201 ** sqlite3changeset_apply() function silently ignore any modifications to the 11202 ** sqlite_stat1 table that are part of a changeset or patchset. 11203 */ 11204 SQLITE_API int sqlite3session_attach( 11205 sqlite3_session *pSession, /* Session object */ 11206 const char *zTab /* Table name */ 11207 ); 11208 11209 /* 11210 ** CAPI3REF: Set a table filter on a Session Object. 11211 ** METHOD: sqlite3_session 11212 ** 11213 ** The second argument (xFilter) is the "filter callback". For changes to rows 11214 ** in tables that are not attached to the Session object, the filter is called 11215 ** to determine whether changes to the table's rows should be tracked or not. 11216 ** If xFilter returns 0, changes are not tracked. Note that once a table is 11217 ** attached, xFilter will not be called again. 11218 */ 11219 SQLITE_API void sqlite3session_table_filter( 11220 sqlite3_session *pSession, /* Session object */ 11221 int(*xFilter)( 11222 void *pCtx, /* Copy of third arg to _filter_table() */ 11223 const char *zTab /* Table name */ 11224 ), 11225 void *pCtx /* First argument passed to xFilter */ 11226 ); 11227 11228 /* 11229 ** CAPI3REF: Generate A Changeset From A Session Object 11230 ** METHOD: sqlite3_session 11231 ** 11232 ** Obtain a changeset containing changes to the tables attached to the 11233 ** session object passed as the first argument. If successful, 11234 ** set *ppChangeset to point to a buffer containing the changeset 11235 ** and *pnChangeset to the size of the changeset in bytes before returning 11236 ** SQLITE_OK. If an error occurs, set both *ppChangeset and *pnChangeset to 11237 ** zero and return an SQLite error code. 11238 ** 11239 ** A changeset consists of zero or more INSERT, UPDATE and/or DELETE changes, 11240 ** each representing a change to a single row of an attached table. An INSERT 11241 ** change contains the values of each field of a new database row. A DELETE 11242 ** contains the original values of each field of a deleted database row. An 11243 ** UPDATE change contains the original values of each field of an updated 11244 ** database row along with the updated values for each updated non-primary-key 11245 ** column. It is not possible for an UPDATE change to represent a change that 11246 ** modifies the values of primary key columns. If such a change is made, it 11247 ** is represented in a changeset as a DELETE followed by an INSERT. 11248 ** 11249 ** Changes are not recorded for rows that have NULL values stored in one or 11250 ** more of their PRIMARY KEY columns. If such a row is inserted or deleted, 11251 ** no corresponding change is present in the changesets returned by this 11252 ** function. If an existing row with one or more NULL values stored in 11253 ** PRIMARY KEY columns is updated so that all PRIMARY KEY columns are non-NULL, 11254 ** only an INSERT is appears in the changeset. Similarly, if an existing row 11255 ** with non-NULL PRIMARY KEY values is updated so that one or more of its 11256 ** PRIMARY KEY columns are set to NULL, the resulting changeset contains a 11257 ** DELETE change only. 11258 ** 11259 ** The contents of a changeset may be traversed using an iterator created 11260 ** using the [sqlite3changeset_start()] API. A changeset may be applied to 11261 ** a database with a compatible schema using the [sqlite3changeset_apply()] 11262 ** API. 11263 ** 11264 ** Within a changeset generated by this function, all changes related to a 11265 ** single table are grouped together. In other words, when iterating through 11266 ** a changeset or when applying a changeset to a database, all changes related 11267 ** to a single table are processed before moving on to the next table. Tables 11268 ** are sorted in the same order in which they were attached (or auto-attached) 11269 ** to the sqlite3_session object. The order in which the changes related to 11270 ** a single table are stored is undefined. 11271 ** 11272 ** Following a successful call to this function, it is the responsibility of 11273 ** the caller to eventually free the buffer that *ppChangeset points to using 11274 ** [sqlite3_free()]. 11275 ** 11276 ** <h3>Changeset Generation</h3> 11277 ** 11278 ** Once a table has been attached to a session object, the session object 11279 ** records the primary key values of all new rows inserted into the table. 11280 ** It also records the original primary key and other column values of any 11281 ** deleted or updated rows. For each unique primary key value, data is only 11282 ** recorded once - the first time a row with said primary key is inserted, 11283 ** updated or deleted in the lifetime of the session. 11284 ** 11285 ** There is one exception to the previous paragraph: when a row is inserted, 11286 ** updated or deleted, if one or more of its primary key columns contain a 11287 ** NULL value, no record of the change is made. 11288 ** 11289 ** The session object therefore accumulates two types of records - those 11290 ** that consist of primary key values only (created when the user inserts 11291 ** a new record) and those that consist of the primary key values and the 11292 ** original values of other table columns (created when the users deletes 11293 ** or updates a record). 11294 ** 11295 ** When this function is called, the requested changeset is created using 11296 ** both the accumulated records and the current contents of the database 11297 ** file. Specifically: 11298 ** 11299 ** <ul> 11300 ** <li> For each record generated by an insert, the database is queried 11301 ** for a row with a matching primary key. If one is found, an INSERT 11302 ** change is added to the changeset. If no such row is found, no change 11303 ** is added to the changeset. 11304 ** 11305 ** <li> For each record generated by an update or delete, the database is 11306 ** queried for a row with a matching primary key. If such a row is 11307 ** found and one or more of the non-primary key fields have been 11308 ** modified from their original values, an UPDATE change is added to 11309 ** the changeset. Or, if no such row is found in the table, a DELETE 11310 ** change is added to the changeset. If there is a row with a matching 11311 ** primary key in the database, but all fields contain their original 11312 ** values, no change is added to the changeset. 11313 ** </ul> 11314 ** 11315 ** This means, amongst other things, that if a row is inserted and then later 11316 ** deleted while a session object is active, neither the insert nor the delete 11317 ** will be present in the changeset. Or if a row is deleted and then later a 11318 ** row with the same primary key values inserted while a session object is 11319 ** active, the resulting changeset will contain an UPDATE change instead of 11320 ** a DELETE and an INSERT. 11321 ** 11322 ** When a session object is disabled (see the [sqlite3session_enable()] API), 11323 ** it does not accumulate records when rows are inserted, updated or deleted. 11324 ** This may appear to have some counter-intuitive effects if a single row 11325 ** is written to more than once during a session. For example, if a row 11326 ** is inserted while a session object is enabled, then later deleted while 11327 ** the same session object is disabled, no INSERT record will appear in the 11328 ** changeset, even though the delete took place while the session was disabled. 11329 ** Or, if one field of a row is updated while a session is disabled, and 11330 ** another field of the same row is updated while the session is enabled, the 11331 ** resulting changeset will contain an UPDATE change that updates both fields. 11332 */ 11333 SQLITE_API int sqlite3session_changeset( 11334 sqlite3_session *pSession, /* Session object */ 11335 int *pnChangeset, /* OUT: Size of buffer at *ppChangeset */ 11336 void **ppChangeset /* OUT: Buffer containing changeset */ 11337 ); 11338 11339 /* 11340 ** CAPI3REF: Return An Upper-limit For The Size Of The Changeset 11341 ** METHOD: sqlite3_session 11342 ** 11343 ** By default, this function always returns 0. For it to return 11344 ** a useful result, the sqlite3_session object must have been configured 11345 ** to enable this API using sqlite3session_object_config() with the 11346 ** SQLITE_SESSION_OBJCONFIG_SIZE verb. 11347 ** 11348 ** When enabled, this function returns an upper limit, in bytes, for the size 11349 ** of the changeset that might be produced if sqlite3session_changeset() were 11350 ** called. The final changeset size might be equal to or smaller than the 11351 ** size in bytes returned by this function. 11352 */ 11353 SQLITE_API sqlite3_int64 sqlite3session_changeset_size(sqlite3_session *pSession); 11354 11355 /* 11356 ** CAPI3REF: Load The Difference Between Tables Into A Session 11357 ** METHOD: sqlite3_session 11358 ** 11359 ** If it is not already attached to the session object passed as the first 11360 ** argument, this function attaches table zTbl in the same manner as the 11361 ** [sqlite3session_attach()] function. If zTbl does not exist, or if it 11362 ** does not have a primary key, this function is a no-op (but does not return 11363 ** an error). 11364 ** 11365 ** Argument zFromDb must be the name of a database ("main", "temp" etc.) 11366 ** attached to the same database handle as the session object that contains 11367 ** a table compatible with the table attached to the session by this function. 11368 ** A table is considered compatible if it: 11369 ** 11370 ** <ul> 11371 ** <li> Has the same name, 11372 ** <li> Has the same set of columns declared in the same order, and 11373 ** <li> Has the same PRIMARY KEY definition. 11374 ** </ul> 11375 ** 11376 ** If the tables are not compatible, SQLITE_SCHEMA is returned. If the tables 11377 ** are compatible but do not have any PRIMARY KEY columns, it is not an error 11378 ** but no changes are added to the session object. As with other session 11379 ** APIs, tables without PRIMARY KEYs are simply ignored. 11380 ** 11381 ** This function adds a set of changes to the session object that could be 11382 ** used to update the table in database zFrom (call this the "from-table") 11383 ** so that its content is the same as the table attached to the session 11384 ** object (call this the "to-table"). Specifically: 11385 ** 11386 ** <ul> 11387 ** <li> For each row (primary key) that exists in the to-table but not in 11388 ** the from-table, an INSERT record is added to the session object. 11389 ** 11390 ** <li> For each row (primary key) that exists in the to-table but not in 11391 ** the from-table, a DELETE record is added to the session object. 11392 ** 11393 ** <li> For each row (primary key) that exists in both tables, but features 11394 ** different non-PK values in each, an UPDATE record is added to the 11395 ** session. 11396 ** </ul> 11397 ** 11398 ** To clarify, if this function is called and then a changeset constructed 11399 ** using [sqlite3session_changeset()], then after applying that changeset to 11400 ** database zFrom the contents of the two compatible tables would be 11401 ** identical. 11402 ** 11403 ** It an error if database zFrom does not exist or does not contain the 11404 ** required compatible table. 11405 ** 11406 ** If the operation is successful, SQLITE_OK is returned. Otherwise, an SQLite 11407 ** error code. In this case, if argument pzErrMsg is not NULL, *pzErrMsg 11408 ** may be set to point to a buffer containing an English language error 11409 ** message. It is the responsibility of the caller to free this buffer using 11410 ** sqlite3_free(). 11411 */ 11412 SQLITE_API int sqlite3session_diff( 11413 sqlite3_session *pSession, 11414 const char *zFromDb, 11415 const char *zTbl, 11416 char **pzErrMsg 11417 ); 11418 11419 11420 /* 11421 ** CAPI3REF: Generate A Patchset From A Session Object 11422 ** METHOD: sqlite3_session 11423 ** 11424 ** The differences between a patchset and a changeset are that: 11425 ** 11426 ** <ul> 11427 ** <li> DELETE records consist of the primary key fields only. The 11428 ** original values of other fields are omitted. 11429 ** <li> The original values of any modified fields are omitted from 11430 ** UPDATE records. 11431 ** </ul> 11432 ** 11433 ** A patchset blob may be used with up to date versions of all 11434 ** sqlite3changeset_xxx API functions except for sqlite3changeset_invert(), 11435 ** which returns SQLITE_CORRUPT if it is passed a patchset. Similarly, 11436 ** attempting to use a patchset blob with old versions of the 11437 ** sqlite3changeset_xxx APIs also provokes an SQLITE_CORRUPT error. 11438 ** 11439 ** Because the non-primary key "old.*" fields are omitted, no 11440 ** SQLITE_CHANGESET_DATA conflicts can be detected or reported if a patchset 11441 ** is passed to the sqlite3changeset_apply() API. Other conflict types work 11442 ** in the same way as for changesets. 11443 ** 11444 ** Changes within a patchset are ordered in the same way as for changesets 11445 ** generated by the sqlite3session_changeset() function (i.e. all changes for 11446 ** a single table are grouped together, tables appear in the order in which 11447 ** they were attached to the session object). 11448 */ 11449 SQLITE_API int sqlite3session_patchset( 11450 sqlite3_session *pSession, /* Session object */ 11451 int *pnPatchset, /* OUT: Size of buffer at *ppPatchset */ 11452 void **ppPatchset /* OUT: Buffer containing patchset */ 11453 ); 11454 11455 /* 11456 ** CAPI3REF: Test if a changeset has recorded any changes. 11457 ** 11458 ** Return non-zero if no changes to attached tables have been recorded by 11459 ** the session object passed as the first argument. Otherwise, if one or 11460 ** more changes have been recorded, return zero. 11461 ** 11462 ** Even if this function returns zero, it is possible that calling 11463 ** [sqlite3session_changeset()] on the session handle may still return a 11464 ** changeset that contains no changes. This can happen when a row in 11465 ** an attached table is modified and then later on the original values 11466 ** are restored. However, if this function returns non-zero, then it is 11467 ** guaranteed that a call to sqlite3session_changeset() will return a 11468 ** changeset containing zero changes. 11469 */ 11470 SQLITE_API int sqlite3session_isempty(sqlite3_session *pSession); 11471 11472 /* 11473 ** CAPI3REF: Query for the amount of heap memory used by a session object. 11474 ** 11475 ** This API returns the total amount of heap memory in bytes currently 11476 ** used by the session object passed as the only argument. 11477 */ 11478 SQLITE_API sqlite3_int64 sqlite3session_memory_used(sqlite3_session *pSession); 11479 11480 /* 11481 ** CAPI3REF: Create An Iterator To Traverse A Changeset 11482 ** CONSTRUCTOR: sqlite3_changeset_iter 11483 ** 11484 ** Create an iterator used to iterate through the contents of a changeset. 11485 ** If successful, *pp is set to point to the iterator handle and SQLITE_OK 11486 ** is returned. Otherwise, if an error occurs, *pp is set to zero and an 11487 ** SQLite error code is returned. 11488 ** 11489 ** The following functions can be used to advance and query a changeset 11490 ** iterator created by this function: 11491 ** 11492 ** <ul> 11493 ** <li> [sqlite3changeset_next()] 11494 ** <li> [sqlite3changeset_op()] 11495 ** <li> [sqlite3changeset_new()] 11496 ** <li> [sqlite3changeset_old()] 11497 ** </ul> 11498 ** 11499 ** It is the responsibility of the caller to eventually destroy the iterator 11500 ** by passing it to [sqlite3changeset_finalize()]. The buffer containing the 11501 ** changeset (pChangeset) must remain valid until after the iterator is 11502 ** destroyed. 11503 ** 11504 ** Assuming the changeset blob was created by one of the 11505 ** [sqlite3session_changeset()], [sqlite3changeset_concat()] or 11506 ** [sqlite3changeset_invert()] functions, all changes within the changeset 11507 ** that apply to a single table are grouped together. This means that when 11508 ** an application iterates through a changeset using an iterator created by 11509 ** this function, all changes that relate to a single table are visited 11510 ** consecutively. There is no chance that the iterator will visit a change 11511 ** the applies to table X, then one for table Y, and then later on visit 11512 ** another change for table X. 11513 ** 11514 ** The behavior of sqlite3changeset_start_v2() and its streaming equivalent 11515 ** may be modified by passing a combination of 11516 ** [SQLITE_CHANGESETSTART_INVERT | supported flags] as the 4th parameter. 11517 ** 11518 ** Note that the sqlite3changeset_start_v2() API is still <b>experimental</b> 11519 ** and therefore subject to change. 11520 */ 11521 SQLITE_API int sqlite3changeset_start( 11522 sqlite3_changeset_iter **pp, /* OUT: New changeset iterator handle */ 11523 int nChangeset, /* Size of changeset blob in bytes */ 11524 void *pChangeset /* Pointer to blob containing changeset */ 11525 ); 11526 SQLITE_API int sqlite3changeset_start_v2( 11527 sqlite3_changeset_iter **pp, /* OUT: New changeset iterator handle */ 11528 int nChangeset, /* Size of changeset blob in bytes */ 11529 void *pChangeset, /* Pointer to blob containing changeset */ 11530 int flags /* SESSION_CHANGESETSTART_* flags */ 11531 ); 11532 11533 /* 11534 ** CAPI3REF: Flags for sqlite3changeset_start_v2 11535 ** 11536 ** The following flags may passed via the 4th parameter to 11537 ** [sqlite3changeset_start_v2] and [sqlite3changeset_start_v2_strm]: 11538 ** 11539 ** <dt>SQLITE_CHANGESETAPPLY_INVERT <dd> 11540 ** Invert the changeset while iterating through it. This is equivalent to 11541 ** inverting a changeset using sqlite3changeset_invert() before applying it. 11542 ** It is an error to specify this flag with a patchset. 11543 */ 11544 #define SQLITE_CHANGESETSTART_INVERT 0x0002 11545 11546 11547 /* 11548 ** CAPI3REF: Advance A Changeset Iterator 11549 ** METHOD: sqlite3_changeset_iter 11550 ** 11551 ** This function may only be used with iterators created by the function 11552 ** [sqlite3changeset_start()]. If it is called on an iterator passed to 11553 ** a conflict-handler callback by [sqlite3changeset_apply()], SQLITE_MISUSE 11554 ** is returned and the call has no effect. 11555 ** 11556 ** Immediately after an iterator is created by sqlite3changeset_start(), it 11557 ** does not point to any change in the changeset. Assuming the changeset 11558 ** is not empty, the first call to this function advances the iterator to 11559 ** point to the first change in the changeset. Each subsequent call advances 11560 ** the iterator to point to the next change in the changeset (if any). If 11561 ** no error occurs and the iterator points to a valid change after a call 11562 ** to sqlite3changeset_next() has advanced it, SQLITE_ROW is returned. 11563 ** Otherwise, if all changes in the changeset have already been visited, 11564 ** SQLITE_DONE is returned. 11565 ** 11566 ** If an error occurs, an SQLite error code is returned. Possible error 11567 ** codes include SQLITE_CORRUPT (if the changeset buffer is corrupt) or 11568 ** SQLITE_NOMEM. 11569 */ 11570 SQLITE_API int sqlite3changeset_next(sqlite3_changeset_iter *pIter); 11571 11572 /* 11573 ** CAPI3REF: Obtain The Current Operation From A Changeset Iterator 11574 ** METHOD: sqlite3_changeset_iter 11575 ** 11576 ** The pIter argument passed to this function may either be an iterator 11577 ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator 11578 ** created by [sqlite3changeset_start()]. In the latter case, the most recent 11579 ** call to [sqlite3changeset_next()] must have returned [SQLITE_ROW]. If this 11580 ** is not the case, this function returns [SQLITE_MISUSE]. 11581 ** 11582 ** Arguments pOp, pnCol and pzTab may not be NULL. Upon return, three 11583 ** outputs are set through these pointers: 11584 ** 11585 ** *pOp is set to one of [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE], 11586 ** depending on the type of change that the iterator currently points to; 11587 ** 11588 ** *pnCol is set to the number of columns in the table affected by the change; and 11589 ** 11590 ** *pzTab is set to point to a nul-terminated utf-8 encoded string containing 11591 ** the name of the table affected by the current change. The buffer remains 11592 ** valid until either sqlite3changeset_next() is called on the iterator 11593 ** or until the conflict-handler function returns. 11594 ** 11595 ** If pbIndirect is not NULL, then *pbIndirect is set to true (1) if the change 11596 ** is an indirect change, or false (0) otherwise. See the documentation for 11597 ** [sqlite3session_indirect()] for a description of direct and indirect 11598 ** changes. 11599 ** 11600 ** If no error occurs, SQLITE_OK is returned. If an error does occur, an 11601 ** SQLite error code is returned. The values of the output variables may not 11602 ** be trusted in this case. 11603 */ 11604 SQLITE_API int sqlite3changeset_op( 11605 sqlite3_changeset_iter *pIter, /* Iterator object */ 11606 const char **pzTab, /* OUT: Pointer to table name */ 11607 int *pnCol, /* OUT: Number of columns in table */ 11608 int *pOp, /* OUT: SQLITE_INSERT, DELETE or UPDATE */ 11609 int *pbIndirect /* OUT: True for an 'indirect' change */ 11610 ); 11611 11612 /* 11613 ** CAPI3REF: Obtain The Primary Key Definition Of A Table 11614 ** METHOD: sqlite3_changeset_iter 11615 ** 11616 ** For each modified table, a changeset includes the following: 11617 ** 11618 ** <ul> 11619 ** <li> The number of columns in the table, and 11620 ** <li> Which of those columns make up the tables PRIMARY KEY. 11621 ** </ul> 11622 ** 11623 ** This function is used to find which columns comprise the PRIMARY KEY of 11624 ** the table modified by the change that iterator pIter currently points to. 11625 ** If successful, *pabPK is set to point to an array of nCol entries, where 11626 ** nCol is the number of columns in the table. Elements of *pabPK are set to 11627 ** 0x01 if the corresponding column is part of the tables primary key, or 11628 ** 0x00 if it is not. 11629 ** 11630 ** If argument pnCol is not NULL, then *pnCol is set to the number of columns 11631 ** in the table. 11632 ** 11633 ** If this function is called when the iterator does not point to a valid 11634 ** entry, SQLITE_MISUSE is returned and the output variables zeroed. Otherwise, 11635 ** SQLITE_OK is returned and the output variables populated as described 11636 ** above. 11637 */ 11638 SQLITE_API int sqlite3changeset_pk( 11639 sqlite3_changeset_iter *pIter, /* Iterator object */ 11640 unsigned char **pabPK, /* OUT: Array of boolean - true for PK cols */ 11641 int *pnCol /* OUT: Number of entries in output array */ 11642 ); 11643 11644 /* 11645 ** CAPI3REF: Obtain old.* Values From A Changeset Iterator 11646 ** METHOD: sqlite3_changeset_iter 11647 ** 11648 ** The pIter argument passed to this function may either be an iterator 11649 ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator 11650 ** created by [sqlite3changeset_start()]. In the latter case, the most recent 11651 ** call to [sqlite3changeset_next()] must have returned SQLITE_ROW. 11652 ** Furthermore, it may only be called if the type of change that the iterator 11653 ** currently points to is either [SQLITE_DELETE] or [SQLITE_UPDATE]. Otherwise, 11654 ** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL. 11655 ** 11656 ** Argument iVal must be greater than or equal to 0, and less than the number 11657 ** of columns in the table affected by the current change. Otherwise, 11658 ** [SQLITE_RANGE] is returned and *ppValue is set to NULL. 11659 ** 11660 ** If successful, this function sets *ppValue to point to a protected 11661 ** sqlite3_value object containing the iVal'th value from the vector of 11662 ** original row values stored as part of the UPDATE or DELETE change and 11663 ** returns SQLITE_OK. The name of the function comes from the fact that this 11664 ** is similar to the "old.*" columns available to update or delete triggers. 11665 ** 11666 ** If some other error occurs (e.g. an OOM condition), an SQLite error code 11667 ** is returned and *ppValue is set to NULL. 11668 */ 11669 SQLITE_API int sqlite3changeset_old( 11670 sqlite3_changeset_iter *pIter, /* Changeset iterator */ 11671 int iVal, /* Column number */ 11672 sqlite3_value **ppValue /* OUT: Old value (or NULL pointer) */ 11673 ); 11674 11675 /* 11676 ** CAPI3REF: Obtain new.* Values From A Changeset Iterator 11677 ** METHOD: sqlite3_changeset_iter 11678 ** 11679 ** The pIter argument passed to this function may either be an iterator 11680 ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator 11681 ** created by [sqlite3changeset_start()]. In the latter case, the most recent 11682 ** call to [sqlite3changeset_next()] must have returned SQLITE_ROW. 11683 ** Furthermore, it may only be called if the type of change that the iterator 11684 ** currently points to is either [SQLITE_UPDATE] or [SQLITE_INSERT]. Otherwise, 11685 ** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL. 11686 ** 11687 ** Argument iVal must be greater than or equal to 0, and less than the number 11688 ** of columns in the table affected by the current change. Otherwise, 11689 ** [SQLITE_RANGE] is returned and *ppValue is set to NULL. 11690 ** 11691 ** If successful, this function sets *ppValue to point to a protected 11692 ** sqlite3_value object containing the iVal'th value from the vector of 11693 ** new row values stored as part of the UPDATE or INSERT change and 11694 ** returns SQLITE_OK. If the change is an UPDATE and does not include 11695 ** a new value for the requested column, *ppValue is set to NULL and 11696 ** SQLITE_OK returned. The name of the function comes from the fact that 11697 ** this is similar to the "new.*" columns available to update or delete 11698 ** triggers. 11699 ** 11700 ** If some other error occurs (e.g. an OOM condition), an SQLite error code 11701 ** is returned and *ppValue is set to NULL. 11702 */ 11703 SQLITE_API int sqlite3changeset_new( 11704 sqlite3_changeset_iter *pIter, /* Changeset iterator */ 11705 int iVal, /* Column number */ 11706 sqlite3_value **ppValue /* OUT: New value (or NULL pointer) */ 11707 ); 11708 11709 /* 11710 ** CAPI3REF: Obtain Conflicting Row Values From A Changeset Iterator 11711 ** METHOD: sqlite3_changeset_iter 11712 ** 11713 ** This function should only be used with iterator objects passed to a 11714 ** conflict-handler callback by [sqlite3changeset_apply()] with either 11715 ** [SQLITE_CHANGESET_DATA] or [SQLITE_CHANGESET_CONFLICT]. If this function 11716 ** is called on any other iterator, [SQLITE_MISUSE] is returned and *ppValue 11717 ** is set to NULL. 11718 ** 11719 ** Argument iVal must be greater than or equal to 0, and less than the number 11720 ** of columns in the table affected by the current change. Otherwise, 11721 ** [SQLITE_RANGE] is returned and *ppValue is set to NULL. 11722 ** 11723 ** If successful, this function sets *ppValue to point to a protected 11724 ** sqlite3_value object containing the iVal'th value from the 11725 ** "conflicting row" associated with the current conflict-handler callback 11726 ** and returns SQLITE_OK. 11727 ** 11728 ** If some other error occurs (e.g. an OOM condition), an SQLite error code 11729 ** is returned and *ppValue is set to NULL. 11730 */ 11731 SQLITE_API int sqlite3changeset_conflict( 11732 sqlite3_changeset_iter *pIter, /* Changeset iterator */ 11733 int iVal, /* Column number */ 11734 sqlite3_value **ppValue /* OUT: Value from conflicting row */ 11735 ); 11736 11737 /* 11738 ** CAPI3REF: Determine The Number Of Foreign Key Constraint Violations 11739 ** METHOD: sqlite3_changeset_iter 11740 ** 11741 ** This function may only be called with an iterator passed to an 11742 ** SQLITE_CHANGESET_FOREIGN_KEY conflict handler callback. In this case 11743 ** it sets the output variable to the total number of known foreign key 11744 ** violations in the destination database and returns SQLITE_OK. 11745 ** 11746 ** In all other cases this function returns SQLITE_MISUSE. 11747 */ 11748 SQLITE_API int sqlite3changeset_fk_conflicts( 11749 sqlite3_changeset_iter *pIter, /* Changeset iterator */ 11750 int *pnOut /* OUT: Number of FK violations */ 11751 ); 11752 11753 11754 /* 11755 ** CAPI3REF: Finalize A Changeset Iterator 11756 ** METHOD: sqlite3_changeset_iter 11757 ** 11758 ** This function is used to finalize an iterator allocated with 11759 ** [sqlite3changeset_start()]. 11760 ** 11761 ** This function should only be called on iterators created using the 11762 ** [sqlite3changeset_start()] function. If an application calls this 11763 ** function with an iterator passed to a conflict-handler by 11764 ** [sqlite3changeset_apply()], [SQLITE_MISUSE] is immediately returned and the 11765 ** call has no effect. 11766 ** 11767 ** If an error was encountered within a call to an sqlite3changeset_xxx() 11768 ** function (for example an [SQLITE_CORRUPT] in [sqlite3changeset_next()] or an 11769 ** [SQLITE_NOMEM] in [sqlite3changeset_new()]) then an error code corresponding 11770 ** to that error is returned by this function. Otherwise, SQLITE_OK is 11771 ** returned. This is to allow the following pattern (pseudo-code): 11772 ** 11773 ** <pre> 11774 ** sqlite3changeset_start(); 11775 ** while( SQLITE_ROW==sqlite3changeset_next() ){ 11776 ** // Do something with change. 11777 ** } 11778 ** rc = sqlite3changeset_finalize(); 11779 ** if( rc!=SQLITE_OK ){ 11780 ** // An error has occurred 11781 ** } 11782 ** </pre> 11783 */ 11784 SQLITE_API int sqlite3changeset_finalize(sqlite3_changeset_iter *pIter); 11785 11786 /* 11787 ** CAPI3REF: Invert A Changeset 11788 ** 11789 ** This function is used to "invert" a changeset object. Applying an inverted 11790 ** changeset to a database reverses the effects of applying the uninverted 11791 ** changeset. Specifically: 11792 ** 11793 ** <ul> 11794 ** <li> Each DELETE change is changed to an INSERT, and 11795 ** <li> Each INSERT change is changed to a DELETE, and 11796 ** <li> For each UPDATE change, the old.* and new.* values are exchanged. 11797 ** </ul> 11798 ** 11799 ** This function does not change the order in which changes appear within 11800 ** the changeset. It merely reverses the sense of each individual change. 11801 ** 11802 ** If successful, a pointer to a buffer containing the inverted changeset 11803 ** is stored in *ppOut, the size of the same buffer is stored in *pnOut, and 11804 ** SQLITE_OK is returned. If an error occurs, both *pnOut and *ppOut are 11805 ** zeroed and an SQLite error code returned. 11806 ** 11807 ** It is the responsibility of the caller to eventually call sqlite3_free() 11808 ** on the *ppOut pointer to free the buffer allocation following a successful 11809 ** call to this function. 11810 ** 11811 ** WARNING/TODO: This function currently assumes that the input is a valid 11812 ** changeset. If it is not, the results are undefined. 11813 */ 11814 SQLITE_API int sqlite3changeset_invert( 11815 int nIn, const void *pIn, /* Input changeset */ 11816 int *pnOut, void **ppOut /* OUT: Inverse of input */ 11817 ); 11818 11819 /* 11820 ** CAPI3REF: Concatenate Two Changeset Objects 11821 ** 11822 ** This function is used to concatenate two changesets, A and B, into a 11823 ** single changeset. The result is a changeset equivalent to applying 11824 ** changeset A followed by changeset B. 11825 ** 11826 ** This function combines the two input changesets using an 11827 ** sqlite3_changegroup object. Calling it produces similar results as the 11828 ** following code fragment: 11829 ** 11830 ** <pre> 11831 ** sqlite3_changegroup *pGrp; 11832 ** rc = sqlite3_changegroup_new(&pGrp); 11833 ** if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nA, pA); 11834 ** if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nB, pB); 11835 ** if( rc==SQLITE_OK ){ 11836 ** rc = sqlite3changegroup_output(pGrp, pnOut, ppOut); 11837 ** }else{ 11838 ** *ppOut = 0; 11839 ** *pnOut = 0; 11840 ** } 11841 ** </pre> 11842 ** 11843 ** Refer to the sqlite3_changegroup documentation below for details. 11844 */ 11845 SQLITE_API int sqlite3changeset_concat( 11846 int nA, /* Number of bytes in buffer pA */ 11847 void *pA, /* Pointer to buffer containing changeset A */ 11848 int nB, /* Number of bytes in buffer pB */ 11849 void *pB, /* Pointer to buffer containing changeset B */ 11850 int *pnOut, /* OUT: Number of bytes in output changeset */ 11851 void **ppOut /* OUT: Buffer containing output changeset */ 11852 ); 11853 11854 11855 /* 11856 ** CAPI3REF: Upgrade the Schema of a Changeset/Patchset 11857 */ 11858 SQLITE_API int sqlite3changeset_upgrade( 11859 sqlite3 *db, 11860 const char *zDb, 11861 int nIn, const void *pIn, /* Input changeset */ 11862 int *pnOut, void **ppOut /* OUT: Inverse of input */ 11863 ); 11864 11865 11866 11867 /* 11868 ** CAPI3REF: Changegroup Handle 11869 ** 11870 ** A changegroup is an object used to combine two or more 11871 ** [changesets] or [patchsets] 11872 */ 11873 typedef struct sqlite3_changegroup sqlite3_changegroup; 11874 11875 /* 11876 ** CAPI3REF: Create A New Changegroup Object 11877 ** CONSTRUCTOR: sqlite3_changegroup 11878 ** 11879 ** An sqlite3_changegroup object is used to combine two or more changesets 11880 ** (or patchsets) into a single changeset (or patchset). A single changegroup 11881 ** object may combine changesets or patchsets, but not both. The output is 11882 ** always in the same format as the input. 11883 ** 11884 ** If successful, this function returns SQLITE_OK and populates (*pp) with 11885 ** a pointer to a new sqlite3_changegroup object before returning. The caller 11886 ** should eventually free the returned object using a call to 11887 ** sqlite3changegroup_delete(). If an error occurs, an SQLite error code 11888 ** (i.e. SQLITE_NOMEM) is returned and *pp is set to NULL. 11889 ** 11890 ** The usual usage pattern for an sqlite3_changegroup object is as follows: 11891 ** 11892 ** <ul> 11893 ** <li> It is created using a call to sqlite3changegroup_new(). 11894 ** 11895 ** <li> Zero or more changesets (or patchsets) are added to the object 11896 ** by calling sqlite3changegroup_add(). 11897 ** 11898 ** <li> The result of combining all input changesets together is obtained 11899 ** by the application via a call to sqlite3changegroup_output(). 11900 ** 11901 ** <li> The object is deleted using a call to sqlite3changegroup_delete(). 11902 ** </ul> 11903 ** 11904 ** Any number of calls to add() and output() may be made between the calls to 11905 ** new() and delete(), and in any order. 11906 ** 11907 ** As well as the regular sqlite3changegroup_add() and 11908 ** sqlite3changegroup_output() functions, also available are the streaming 11909 ** versions sqlite3changegroup_add_strm() and sqlite3changegroup_output_strm(). 11910 */ 11911 SQLITE_API int sqlite3changegroup_new(sqlite3_changegroup **pp); 11912 11913 /* 11914 ** CAPI3REF: Add a Schema to a Changegroup 11915 ** METHOD: sqlite3_changegroup_schema 11916 ** 11917 ** This method may be used to optionally enforce the rule that the changesets 11918 ** added to the changegroup handle must match the schema of database zDb 11919 ** ("main", "temp", or the name of an attached database). If 11920 ** sqlite3changegroup_add() is called to add a changeset that is not compatible 11921 ** with the configured schema, SQLITE_SCHEMA is returned and the changegroup 11922 ** object is left in an undefined state. 11923 ** 11924 ** A changeset schema is considered compatible with the database schema in 11925 ** the same way as for sqlite3changeset_apply(). Specifically, for each 11926 ** table in the changeset, there exists a database table with: 11927 ** 11928 ** <ul> 11929 ** <li> The name identified by the changeset, and 11930 ** <li> at least as many columns as recorded in the changeset, and 11931 ** <li> the primary key columns in the same position as recorded in 11932 ** the changeset. 11933 ** </ul> 11934 ** 11935 ** The output of the changegroup object always has the same schema as the 11936 ** database nominated using this function. In cases where changesets passed 11937 ** to sqlite3changegroup_add() have fewer columns than the corresponding table 11938 ** in the database schema, these are filled in using the default column 11939 ** values from the database schema. This makes it possible to combined 11940 ** changesets that have different numbers of columns for a single table 11941 ** within a changegroup, provided that they are otherwise compatible. 11942 */ 11943 SQLITE_API int sqlite3changegroup_schema(sqlite3_changegroup*, sqlite3*, const char *zDb); 11944 11945 /* 11946 ** CAPI3REF: Add A Changeset To A Changegroup 11947 ** METHOD: sqlite3_changegroup 11948 ** 11949 ** Add all changes within the changeset (or patchset) in buffer pData (size 11950 ** nData bytes) to the changegroup. 11951 ** 11952 ** If the buffer contains a patchset, then all prior calls to this function 11953 ** on the same changegroup object must also have specified patchsets. Or, if 11954 ** the buffer contains a changeset, so must have the earlier calls to this 11955 ** function. Otherwise, SQLITE_ERROR is returned and no changes are added 11956 ** to the changegroup. 11957 ** 11958 ** Rows within the changeset and changegroup are identified by the values in 11959 ** their PRIMARY KEY columns. A change in the changeset is considered to 11960 ** apply to the same row as a change already present in the changegroup if 11961 ** the two rows have the same primary key. 11962 ** 11963 ** Changes to rows that do not already appear in the changegroup are 11964 ** simply copied into it. Or, if both the new changeset and the changegroup 11965 ** contain changes that apply to a single row, the final contents of the 11966 ** changegroup depends on the type of each change, as follows: 11967 ** 11968 ** <table border=1 style="margin-left:8ex;margin-right:8ex"> 11969 ** <tr><th style="white-space:pre">Existing Change </th> 11970 ** <th style="white-space:pre">New Change </th> 11971 ** <th>Output Change 11972 ** <tr><td>INSERT <td>INSERT <td> 11973 ** The new change is ignored. This case does not occur if the new 11974 ** changeset was recorded immediately after the changesets already 11975 ** added to the changegroup. 11976 ** <tr><td>INSERT <td>UPDATE <td> 11977 ** The INSERT change remains in the changegroup. The values in the 11978 ** INSERT change are modified as if the row was inserted by the 11979 ** existing change and then updated according to the new change. 11980 ** <tr><td>INSERT <td>DELETE <td> 11981 ** The existing INSERT is removed from the changegroup. The DELETE is 11982 ** not added. 11983 ** <tr><td>UPDATE <td>INSERT <td> 11984 ** The new change is ignored. This case does not occur if the new 11985 ** changeset was recorded immediately after the changesets already 11986 ** added to the changegroup. 11987 ** <tr><td>UPDATE <td>UPDATE <td> 11988 ** The existing UPDATE remains within the changegroup. It is amended 11989 ** so that the accompanying values are as if the row was updated once 11990 ** by the existing change and then again by the new change. 11991 ** <tr><td>UPDATE <td>DELETE <td> 11992 ** The existing UPDATE is replaced by the new DELETE within the 11993 ** changegroup. 11994 ** <tr><td>DELETE <td>INSERT <td> 11995 ** If one or more of the column values in the row inserted by the 11996 ** new change differ from those in the row deleted by the existing 11997 ** change, the existing DELETE is replaced by an UPDATE within the 11998 ** changegroup. Otherwise, if the inserted row is exactly the same 11999 ** as the deleted row, the existing DELETE is simply discarded. 12000 ** <tr><td>DELETE <td>UPDATE <td> 12001 ** The new change is ignored. This case does not occur if the new 12002 ** changeset was recorded immediately after the changesets already 12003 ** added to the changegroup. 12004 ** <tr><td>DELETE <td>DELETE <td> 12005 ** The new change is ignored. This case does not occur if the new 12006 ** changeset was recorded immediately after the changesets already 12007 ** added to the changegroup. 12008 ** </table> 12009 ** 12010 ** If the new changeset contains changes to a table that is already present 12011 ** in the changegroup, then the number of columns and the position of the 12012 ** primary key columns for the table must be consistent. If this is not the 12013 ** case, this function fails with SQLITE_SCHEMA. Except, if the changegroup 12014 ** object has been configured with a database schema using the 12015 ** sqlite3changegroup_schema() API, then it is possible to combine changesets 12016 ** with different numbers of columns for a single table, provided that 12017 ** they are otherwise compatible. 12018 ** 12019 ** If the input changeset appears to be corrupt and the corruption is 12020 ** detected, SQLITE_CORRUPT is returned. Or, if an out-of-memory condition 12021 ** occurs during processing, this function returns SQLITE_NOMEM. 12022 ** 12023 ** In all cases, if an error occurs the state of the final contents of the 12024 ** changegroup is undefined. If no error occurs, SQLITE_OK is returned. 12025 */ 12026 SQLITE_API int sqlite3changegroup_add(sqlite3_changegroup*, int nData, void *pData); 12027 12028 /* 12029 ** CAPI3REF: Add A Single Change To A Changegroup 12030 ** METHOD: sqlite3_changegroup 12031 ** 12032 ** This function adds the single change currently indicated by the iterator 12033 ** passed as the second argument to the changegroup object. The rules for 12034 ** adding the change are just as described for [sqlite3changegroup_add()]. 12035 ** 12036 ** If the change is successfully added to the changegroup, SQLITE_OK is 12037 ** returned. Otherwise, an SQLite error code is returned. 12038 ** 12039 ** The iterator must point to a valid entry when this function is called. 12040 ** If it does not, SQLITE_ERROR is returned and no change is added to the 12041 ** changegroup. Additionally, the iterator must not have been opened with 12042 ** the SQLITE_CHANGESETAPPLY_INVERT flag. In this case SQLITE_ERROR is also 12043 ** returned. 12044 */ 12045 SQLITE_API int sqlite3changegroup_add_change( 12046 sqlite3_changegroup*, 12047 sqlite3_changeset_iter* 12048 ); 12049 12050 12051 12052 /* 12053 ** CAPI3REF: Obtain A Composite Changeset From A Changegroup 12054 ** METHOD: sqlite3_changegroup 12055 ** 12056 ** Obtain a buffer containing a changeset (or patchset) representing the 12057 ** current contents of the changegroup. If the inputs to the changegroup 12058 ** were themselves changesets, the output is a changeset. Or, if the 12059 ** inputs were patchsets, the output is also a patchset. 12060 ** 12061 ** As with the output of the sqlite3session_changeset() and 12062 ** sqlite3session_patchset() functions, all changes related to a single 12063 ** table are grouped together in the output of this function. Tables appear 12064 ** in the same order as for the very first changeset added to the changegroup. 12065 ** If the second or subsequent changesets added to the changegroup contain 12066 ** changes for tables that do not appear in the first changeset, they are 12067 ** appended onto the end of the output changeset, again in the order in 12068 ** which they are first encountered. 12069 ** 12070 ** If an error occurs, an SQLite error code is returned and the output 12071 ** variables (*pnData) and (*ppData) are set to 0. Otherwise, SQLITE_OK 12072 ** is returned and the output variables are set to the size of and a 12073 ** pointer to the output buffer, respectively. In this case it is the 12074 ** responsibility of the caller to eventually free the buffer using a 12075 ** call to sqlite3_free(). 12076 */ 12077 SQLITE_API int sqlite3changegroup_output( 12078 sqlite3_changegroup*, 12079 int *pnData, /* OUT: Size of output buffer in bytes */ 12080 void **ppData /* OUT: Pointer to output buffer */ 12081 ); 12082 12083 /* 12084 ** CAPI3REF: Delete A Changegroup Object 12085 ** DESTRUCTOR: sqlite3_changegroup 12086 */ 12087 SQLITE_API void sqlite3changegroup_delete(sqlite3_changegroup*); 12088 12089 /* 12090 ** CAPI3REF: Apply A Changeset To A Database 12091 ** 12092 ** Apply a changeset or patchset to a database. These functions attempt to 12093 ** update the "main" database attached to handle db with the changes found in 12094 ** the changeset passed via the second and third arguments. 12095 ** 12096 ** The fourth argument (xFilter) passed to these functions is the "filter 12097 ** callback". If it is not NULL, then for each table affected by at least one 12098 ** change in the changeset, the filter callback is invoked with 12099 ** the table name as the second argument, and a copy of the context pointer 12100 ** passed as the sixth argument as the first. If the "filter callback" 12101 ** returns zero, then no attempt is made to apply any changes to the table. 12102 ** Otherwise, if the return value is non-zero or the xFilter argument to 12103 ** is NULL, all changes related to the table are attempted. 12104 ** 12105 ** For each table that is not excluded by the filter callback, this function 12106 ** tests that the target database contains a compatible table. A table is 12107 ** considered compatible if all of the following are true: 12108 ** 12109 ** <ul> 12110 ** <li> The table has the same name as the name recorded in the 12111 ** changeset, and 12112 ** <li> The table has at least as many columns as recorded in the 12113 ** changeset, and 12114 ** <li> The table has primary key columns in the same position as 12115 ** recorded in the changeset. 12116 ** </ul> 12117 ** 12118 ** If there is no compatible table, it is not an error, but none of the 12119 ** changes associated with the table are applied. A warning message is issued 12120 ** via the sqlite3_log() mechanism with the error code SQLITE_SCHEMA. At most 12121 ** one such warning is issued for each table in the changeset. 12122 ** 12123 ** For each change for which there is a compatible table, an attempt is made 12124 ** to modify the table contents according to the UPDATE, INSERT or DELETE 12125 ** change. If a change cannot be applied cleanly, the conflict handler 12126 ** function passed as the fifth argument to sqlite3changeset_apply() may be 12127 ** invoked. A description of exactly when the conflict handler is invoked for 12128 ** each type of change is below. 12129 ** 12130 ** Unlike the xFilter argument, xConflict may not be passed NULL. The results 12131 ** of passing anything other than a valid function pointer as the xConflict 12132 ** argument are undefined. 12133 ** 12134 ** Each time the conflict handler function is invoked, it must return one 12135 ** of [SQLITE_CHANGESET_OMIT], [SQLITE_CHANGESET_ABORT] or 12136 ** [SQLITE_CHANGESET_REPLACE]. SQLITE_CHANGESET_REPLACE may only be returned 12137 ** if the second argument passed to the conflict handler is either 12138 ** SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If the conflict-handler 12139 ** returns an illegal value, any changes already made are rolled back and 12140 ** the call to sqlite3changeset_apply() returns SQLITE_MISUSE. Different 12141 ** actions are taken by sqlite3changeset_apply() depending on the value 12142 ** returned by each invocation of the conflict-handler function. Refer to 12143 ** the documentation for the three 12144 ** [SQLITE_CHANGESET_OMIT|available return values] for details. 12145 ** 12146 ** <dl> 12147 ** <dt>DELETE Changes<dd> 12148 ** For each DELETE change, the function checks if the target database 12149 ** contains a row with the same primary key value (or values) as the 12150 ** original row values stored in the changeset. If it does, and the values 12151 ** stored in all non-primary key columns also match the values stored in 12152 ** the changeset the row is deleted from the target database. 12153 ** 12154 ** If a row with matching primary key values is found, but one or more of 12155 ** the non-primary key fields contains a value different from the original 12156 ** row value stored in the changeset, the conflict-handler function is 12157 ** invoked with [SQLITE_CHANGESET_DATA] as the second argument. If the 12158 ** database table has more columns than are recorded in the changeset, 12159 ** only the values of those non-primary key fields are compared against 12160 ** the current database contents - any trailing database table columns 12161 ** are ignored. 12162 ** 12163 ** If no row with matching primary key values is found in the database, 12164 ** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND] 12165 ** passed as the second argument. 12166 ** 12167 ** If the DELETE operation is attempted, but SQLite returns SQLITE_CONSTRAINT 12168 ** (which can only happen if a foreign key constraint is violated), the 12169 ** conflict-handler function is invoked with [SQLITE_CHANGESET_CONSTRAINT] 12170 ** passed as the second argument. This includes the case where the DELETE 12171 ** operation is attempted because an earlier call to the conflict handler 12172 ** function returned [SQLITE_CHANGESET_REPLACE]. 12173 ** 12174 ** <dt>INSERT Changes<dd> 12175 ** For each INSERT change, an attempt is made to insert the new row into 12176 ** the database. If the changeset row contains fewer fields than the 12177 ** database table, the trailing fields are populated with their default 12178 ** values. 12179 ** 12180 ** If the attempt to insert the row fails because the database already 12181 ** contains a row with the same primary key values, the conflict handler 12182 ** function is invoked with the second argument set to 12183 ** [SQLITE_CHANGESET_CONFLICT]. 12184 ** 12185 ** If the attempt to insert the row fails because of some other constraint 12186 ** violation (e.g. NOT NULL or UNIQUE), the conflict handler function is 12187 ** invoked with the second argument set to [SQLITE_CHANGESET_CONSTRAINT]. 12188 ** This includes the case where the INSERT operation is re-attempted because 12189 ** an earlier call to the conflict handler function returned 12190 ** [SQLITE_CHANGESET_REPLACE]. 12191 ** 12192 ** <dt>UPDATE Changes<dd> 12193 ** For each UPDATE change, the function checks if the target database 12194 ** contains a row with the same primary key value (or values) as the 12195 ** original row values stored in the changeset. If it does, and the values 12196 ** stored in all modified non-primary key columns also match the values 12197 ** stored in the changeset the row is updated within the target database. 12198 ** 12199 ** If a row with matching primary key values is found, but one or more of 12200 ** the modified non-primary key fields contains a value different from an 12201 ** original row value stored in the changeset, the conflict-handler function 12202 ** is invoked with [SQLITE_CHANGESET_DATA] as the second argument. Since 12203 ** UPDATE changes only contain values for non-primary key fields that are 12204 ** to be modified, only those fields need to match the original values to 12205 ** avoid the SQLITE_CHANGESET_DATA conflict-handler callback. 12206 ** 12207 ** If no row with matching primary key values is found in the database, 12208 ** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND] 12209 ** passed as the second argument. 12210 ** 12211 ** If the UPDATE operation is attempted, but SQLite returns 12212 ** SQLITE_CONSTRAINT, the conflict-handler function is invoked with 12213 ** [SQLITE_CHANGESET_CONSTRAINT] passed as the second argument. 12214 ** This includes the case where the UPDATE operation is attempted after 12215 ** an earlier call to the conflict handler function returned 12216 ** [SQLITE_CHANGESET_REPLACE]. 12217 ** </dl> 12218 ** 12219 ** It is safe to execute SQL statements, including those that write to the 12220 ** table that the callback related to, from within the xConflict callback. 12221 ** This can be used to further customize the application's conflict 12222 ** resolution strategy. 12223 ** 12224 ** All changes made by these functions are enclosed in a savepoint transaction. 12225 ** If any other error (aside from a constraint failure when attempting to 12226 ** write to the target database) occurs, then the savepoint transaction is 12227 ** rolled back, restoring the target database to its original state, and an 12228 ** SQLite error code returned. 12229 ** 12230 ** If the output parameters (ppRebase) and (pnRebase) are non-NULL and 12231 ** the input is a changeset (not a patchset), then sqlite3changeset_apply_v2() 12232 ** may set (*ppRebase) to point to a "rebase" that may be used with the 12233 ** sqlite3_rebaser APIs buffer before returning. In this case (*pnRebase) 12234 ** is set to the size of the buffer in bytes. It is the responsibility of the 12235 ** caller to eventually free any such buffer using sqlite3_free(). The buffer 12236 ** is only allocated and populated if one or more conflicts were encountered 12237 ** while applying the patchset. See comments surrounding the sqlite3_rebaser 12238 ** APIs for further details. 12239 ** 12240 ** The behavior of sqlite3changeset_apply_v2() and its streaming equivalent 12241 ** may be modified by passing a combination of 12242 ** [SQLITE_CHANGESETAPPLY_NOSAVEPOINT | supported flags] as the 9th parameter. 12243 ** 12244 ** Note that the sqlite3changeset_apply_v2() API is still <b>experimental</b> 12245 ** and therefore subject to change. 12246 */ 12247 SQLITE_API int sqlite3changeset_apply( 12248 sqlite3 *db, /* Apply change to "main" db of this handle */ 12249 int nChangeset, /* Size of changeset in bytes */ 12250 void *pChangeset, /* Changeset blob */ 12251 int(*xFilter)( 12252 void *pCtx, /* Copy of sixth arg to _apply() */ 12253 const char *zTab /* Table name */ 12254 ), 12255 int(*xConflict)( 12256 void *pCtx, /* Copy of sixth arg to _apply() */ 12257 int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ 12258 sqlite3_changeset_iter *p /* Handle describing change and conflict */ 12259 ), 12260 void *pCtx /* First argument passed to xConflict */ 12261 ); 12262 SQLITE_API int sqlite3changeset_apply_v2( 12263 sqlite3 *db, /* Apply change to "main" db of this handle */ 12264 int nChangeset, /* Size of changeset in bytes */ 12265 void *pChangeset, /* Changeset blob */ 12266 int(*xFilter)( 12267 void *pCtx, /* Copy of sixth arg to _apply() */ 12268 const char *zTab /* Table name */ 12269 ), 12270 int(*xConflict)( 12271 void *pCtx, /* Copy of sixth arg to _apply() */ 12272 int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ 12273 sqlite3_changeset_iter *p /* Handle describing change and conflict */ 12274 ), 12275 void *pCtx, /* First argument passed to xConflict */ 12276 void **ppRebase, int *pnRebase, /* OUT: Rebase data */ 12277 int flags /* SESSION_CHANGESETAPPLY_* flags */ 12278 ); 12279 12280 /* 12281 ** CAPI3REF: Flags for sqlite3changeset_apply_v2 12282 ** 12283 ** The following flags may passed via the 9th parameter to 12284 ** [sqlite3changeset_apply_v2] and [sqlite3changeset_apply_v2_strm]: 12285 ** 12286 ** <dl> 12287 ** <dt>SQLITE_CHANGESETAPPLY_NOSAVEPOINT <dd> 12288 ** Usually, the sessions module encloses all operations performed by 12289 ** a single call to apply_v2() or apply_v2_strm() in a [SAVEPOINT]. The 12290 ** SAVEPOINT is committed if the changeset or patchset is successfully 12291 ** applied, or rolled back if an error occurs. Specifying this flag 12292 ** causes the sessions module to omit this savepoint. In this case, if the 12293 ** caller has an open transaction or savepoint when apply_v2() is called, 12294 ** it may revert the partially applied changeset by rolling it back. 12295 ** 12296 ** <dt>SQLITE_CHANGESETAPPLY_INVERT <dd> 12297 ** Invert the changeset before applying it. This is equivalent to inverting 12298 ** a changeset using sqlite3changeset_invert() before applying it. It is 12299 ** an error to specify this flag with a patchset. 12300 ** 12301 ** <dt>SQLITE_CHANGESETAPPLY_IGNORENOOP <dd> 12302 ** Do not invoke the conflict handler callback for any changes that 12303 ** would not actually modify the database even if they were applied. 12304 ** Specifically, this means that the conflict handler is not invoked 12305 ** for: 12306 ** <ul> 12307 ** <li>a delete change if the row being deleted cannot be found, 12308 ** <li>an update change if the modified fields are already set to 12309 ** their new values in the conflicting row, or 12310 ** <li>an insert change if all fields of the conflicting row match 12311 ** the row being inserted. 12312 ** </ul> 12313 ** 12314 ** <dt>SQLITE_CHANGESETAPPLY_FKNOACTION <dd> 12315 ** If this flag it set, then all foreign key constraints in the target 12316 ** database behave as if they were declared with "ON UPDATE NO ACTION ON 12317 ** DELETE NO ACTION", even if they are actually CASCADE, RESTRICT, SET NULL 12318 ** or SET DEFAULT. 12319 */ 12320 #define SQLITE_CHANGESETAPPLY_NOSAVEPOINT 0x0001 12321 #define SQLITE_CHANGESETAPPLY_INVERT 0x0002 12322 #define SQLITE_CHANGESETAPPLY_IGNORENOOP 0x0004 12323 #define SQLITE_CHANGESETAPPLY_FKNOACTION 0x0008 12324 12325 /* 12326 ** CAPI3REF: Constants Passed To The Conflict Handler 12327 ** 12328 ** Values that may be passed as the second argument to a conflict-handler. 12329 ** 12330 ** <dl> 12331 ** <dt>SQLITE_CHANGESET_DATA<dd> 12332 ** The conflict handler is invoked with CHANGESET_DATA as the second argument 12333 ** when processing a DELETE or UPDATE change if a row with the required 12334 ** PRIMARY KEY fields is present in the database, but one or more other 12335 ** (non primary-key) fields modified by the update do not contain the 12336 ** expected "before" values. 12337 ** 12338 ** The conflicting row, in this case, is the database row with the matching 12339 ** primary key. 12340 ** 12341 ** <dt>SQLITE_CHANGESET_NOTFOUND<dd> 12342 ** The conflict handler is invoked with CHANGESET_NOTFOUND as the second 12343 ** argument when processing a DELETE or UPDATE change if a row with the 12344 ** required PRIMARY KEY fields is not present in the database. 12345 ** 12346 ** There is no conflicting row in this case. The results of invoking the 12347 ** sqlite3changeset_conflict() API are undefined. 12348 ** 12349 ** <dt>SQLITE_CHANGESET_CONFLICT<dd> 12350 ** CHANGESET_CONFLICT is passed as the second argument to the conflict 12351 ** handler while processing an INSERT change if the operation would result 12352 ** in duplicate primary key values. 12353 ** 12354 ** The conflicting row in this case is the database row with the matching 12355 ** primary key. 12356 ** 12357 ** <dt>SQLITE_CHANGESET_FOREIGN_KEY<dd> 12358 ** If foreign key handling is enabled, and applying a changeset leaves the 12359 ** database in a state containing foreign key violations, the conflict 12360 ** handler is invoked with CHANGESET_FOREIGN_KEY as the second argument 12361 ** exactly once before the changeset is committed. If the conflict handler 12362 ** returns CHANGESET_OMIT, the changes, including those that caused the 12363 ** foreign key constraint violation, are committed. Or, if it returns 12364 ** CHANGESET_ABORT, the changeset is rolled back. 12365 ** 12366 ** No current or conflicting row information is provided. The only function 12367 ** it is possible to call on the supplied sqlite3_changeset_iter handle 12368 ** is sqlite3changeset_fk_conflicts(). 12369 ** 12370 ** <dt>SQLITE_CHANGESET_CONSTRAINT<dd> 12371 ** If any other constraint violation occurs while applying a change (i.e. 12372 ** a UNIQUE, CHECK or NOT NULL constraint), the conflict handler is 12373 ** invoked with CHANGESET_CONSTRAINT as the second argument. 12374 ** 12375 ** There is no conflicting row in this case. The results of invoking the 12376 ** sqlite3changeset_conflict() API are undefined. 12377 ** 12378 ** </dl> 12379 */ 12380 #define SQLITE_CHANGESET_DATA 1 12381 #define SQLITE_CHANGESET_NOTFOUND 2 12382 #define SQLITE_CHANGESET_CONFLICT 3 12383 #define SQLITE_CHANGESET_CONSTRAINT 4 12384 #define SQLITE_CHANGESET_FOREIGN_KEY 5 12385 12386 /* 12387 ** CAPI3REF: Constants Returned By The Conflict Handler 12388 ** 12389 ** A conflict handler callback must return one of the following three values. 12390 ** 12391 ** <dl> 12392 ** <dt>SQLITE_CHANGESET_OMIT<dd> 12393 ** If a conflict handler returns this value no special action is taken. The 12394 ** change that caused the conflict is not applied. The session module 12395 ** continues to the next change in the changeset. 12396 ** 12397 ** <dt>SQLITE_CHANGESET_REPLACE<dd> 12398 ** This value may only be returned if the second argument to the conflict 12399 ** handler was SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If this 12400 ** is not the case, any changes applied so far are rolled back and the 12401 ** call to sqlite3changeset_apply() returns SQLITE_MISUSE. 12402 ** 12403 ** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_DATA conflict 12404 ** handler, then the conflicting row is either updated or deleted, depending 12405 ** on the type of change. 12406 ** 12407 ** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_CONFLICT conflict 12408 ** handler, then the conflicting row is removed from the database and a 12409 ** second attempt to apply the change is made. If this second attempt fails, 12410 ** the original row is restored to the database before continuing. 12411 ** 12412 ** <dt>SQLITE_CHANGESET_ABORT<dd> 12413 ** If this value is returned, any changes applied so far are rolled back 12414 ** and the call to sqlite3changeset_apply() returns SQLITE_ABORT. 12415 ** </dl> 12416 */ 12417 #define SQLITE_CHANGESET_OMIT 0 12418 #define SQLITE_CHANGESET_REPLACE 1 12419 #define SQLITE_CHANGESET_ABORT 2 12420 12421 /* 12422 ** CAPI3REF: Rebasing changesets 12423 ** EXPERIMENTAL 12424 ** 12425 ** Suppose there is a site hosting a database in state S0. And that 12426 ** modifications are made that move that database to state S1 and a 12427 ** changeset recorded (the "local" changeset). Then, a changeset based 12428 ** on S0 is received from another site (the "remote" changeset) and 12429 ** applied to the database. The database is then in state 12430 ** (S1+"remote"), where the exact state depends on any conflict 12431 ** resolution decisions (OMIT or REPLACE) made while applying "remote". 12432 ** Rebasing a changeset is to update it to take those conflict 12433 ** resolution decisions into account, so that the same conflicts 12434 ** do not have to be resolved elsewhere in the network. 12435 ** 12436 ** For example, if both the local and remote changesets contain an 12437 ** INSERT of the same key on "CREATE TABLE t1(a PRIMARY KEY, b)": 12438 ** 12439 ** local: INSERT INTO t1 VALUES(1, 'v1'); 12440 ** remote: INSERT INTO t1 VALUES(1, 'v2'); 12441 ** 12442 ** and the conflict resolution is REPLACE, then the INSERT change is 12443 ** removed from the local changeset (it was overridden). Or, if the 12444 ** conflict resolution was "OMIT", then the local changeset is modified 12445 ** to instead contain: 12446 ** 12447 ** UPDATE t1 SET b = 'v2' WHERE a=1; 12448 ** 12449 ** Changes within the local changeset are rebased as follows: 12450 ** 12451 ** <dl> 12452 ** <dt>Local INSERT<dd> 12453 ** This may only conflict with a remote INSERT. If the conflict 12454 ** resolution was OMIT, then add an UPDATE change to the rebased 12455 ** changeset. Or, if the conflict resolution was REPLACE, add 12456 ** nothing to the rebased changeset. 12457 ** 12458 ** <dt>Local DELETE<dd> 12459 ** This may conflict with a remote UPDATE or DELETE. In both cases the 12460 ** only possible resolution is OMIT. If the remote operation was a 12461 ** DELETE, then add no change to the rebased changeset. If the remote 12462 ** operation was an UPDATE, then the old.* fields of change are updated 12463 ** to reflect the new.* values in the UPDATE. 12464 ** 12465 ** <dt>Local UPDATE<dd> 12466 ** This may conflict with a remote UPDATE or DELETE. If it conflicts 12467 ** with a DELETE, and the conflict resolution was OMIT, then the update 12468 ** is changed into an INSERT. Any undefined values in the new.* record 12469 ** from the update change are filled in using the old.* values from 12470 ** the conflicting DELETE. Or, if the conflict resolution was REPLACE, 12471 ** the UPDATE change is simply omitted from the rebased changeset. 12472 ** 12473 ** If conflict is with a remote UPDATE and the resolution is OMIT, then 12474 ** the old.* values are rebased using the new.* values in the remote 12475 ** change. Or, if the resolution is REPLACE, then the change is copied 12476 ** into the rebased changeset with updates to columns also updated by 12477 ** the conflicting remote UPDATE removed. If this means no columns would 12478 ** be updated, the change is omitted. 12479 ** </dl> 12480 ** 12481 ** A local change may be rebased against multiple remote changes 12482 ** simultaneously. If a single key is modified by multiple remote 12483 ** changesets, they are combined as follows before the local changeset 12484 ** is rebased: 12485 ** 12486 ** <ul> 12487 ** <li> If there has been one or more REPLACE resolutions on a 12488 ** key, it is rebased according to a REPLACE. 12489 ** 12490 ** <li> If there have been no REPLACE resolutions on a key, then 12491 ** the local changeset is rebased according to the most recent 12492 ** of the OMIT resolutions. 12493 ** </ul> 12494 ** 12495 ** Note that conflict resolutions from multiple remote changesets are 12496 ** combined on a per-field basis, not per-row. This means that in the 12497 ** case of multiple remote UPDATE operations, some fields of a single 12498 ** local change may be rebased for REPLACE while others are rebased for 12499 ** OMIT. 12500 ** 12501 ** In order to rebase a local changeset, the remote changeset must first 12502 ** be applied to the local database using sqlite3changeset_apply_v2() and 12503 ** the buffer of rebase information captured. Then: 12504 ** 12505 ** <ol> 12506 ** <li> An sqlite3_rebaser object is created by calling 12507 ** sqlite3rebaser_create(). 12508 ** <li> The new object is configured with the rebase buffer obtained from 12509 ** sqlite3changeset_apply_v2() by calling sqlite3rebaser_configure(). 12510 ** If the local changeset is to be rebased against multiple remote 12511 ** changesets, then sqlite3rebaser_configure() should be called 12512 ** multiple times, in the same order that the multiple 12513 ** sqlite3changeset_apply_v2() calls were made. 12514 ** <li> Each local changeset is rebased by calling sqlite3rebaser_rebase(). 12515 ** <li> The sqlite3_rebaser object is deleted by calling 12516 ** sqlite3rebaser_delete(). 12517 ** </ol> 12518 */ 12519 typedef struct sqlite3_rebaser sqlite3_rebaser; 12520 12521 /* 12522 ** CAPI3REF: Create a changeset rebaser object. 12523 ** EXPERIMENTAL 12524 ** 12525 ** Allocate a new changeset rebaser object. If successful, set (*ppNew) to 12526 ** point to the new object and return SQLITE_OK. Otherwise, if an error 12527 ** occurs, return an SQLite error code (e.g. SQLITE_NOMEM) and set (*ppNew) 12528 ** to NULL. 12529 */ 12530 SQLITE_API int sqlite3rebaser_create(sqlite3_rebaser **ppNew); 12531 12532 /* 12533 ** CAPI3REF: Configure a changeset rebaser object. 12534 ** EXPERIMENTAL 12535 ** 12536 ** Configure the changeset rebaser object to rebase changesets according 12537 ** to the conflict resolutions described by buffer pRebase (size nRebase 12538 ** bytes), which must have been obtained from a previous call to 12539 ** sqlite3changeset_apply_v2(). 12540 */ 12541 SQLITE_API int sqlite3rebaser_configure( 12542 sqlite3_rebaser*, 12543 int nRebase, const void *pRebase 12544 ); 12545 12546 /* 12547 ** CAPI3REF: Rebase a changeset 12548 ** EXPERIMENTAL 12549 ** 12550 ** Argument pIn must point to a buffer containing a changeset nIn bytes 12551 ** in size. This function allocates and populates a buffer with a copy 12552 ** of the changeset rebased according to the configuration of the 12553 ** rebaser object passed as the first argument. If successful, (*ppOut) 12554 ** is set to point to the new buffer containing the rebased changeset and 12555 ** (*pnOut) to its size in bytes and SQLITE_OK returned. It is the 12556 ** responsibility of the caller to eventually free the new buffer using 12557 ** sqlite3_free(). Otherwise, if an error occurs, (*ppOut) and (*pnOut) 12558 ** are set to zero and an SQLite error code returned. 12559 */ 12560 SQLITE_API int sqlite3rebaser_rebase( 12561 sqlite3_rebaser*, 12562 int nIn, const void *pIn, 12563 int *pnOut, void **ppOut 12564 ); 12565 12566 /* 12567 ** CAPI3REF: Delete a changeset rebaser object. 12568 ** EXPERIMENTAL 12569 ** 12570 ** Delete the changeset rebaser object and all associated resources. There 12571 ** should be one call to this function for each successful invocation 12572 ** of sqlite3rebaser_create(). 12573 */ 12574 SQLITE_API void sqlite3rebaser_delete(sqlite3_rebaser *p); 12575 12576 /* 12577 ** CAPI3REF: Streaming Versions of API functions. 12578 ** 12579 ** The six streaming API xxx_strm() functions serve similar purposes to the 12580 ** corresponding non-streaming API functions: 12581 ** 12582 ** <table border=1 style="margin-left:8ex;margin-right:8ex"> 12583 ** <tr><th>Streaming function<th>Non-streaming equivalent</th> 12584 ** <tr><td>sqlite3changeset_apply_strm<td>[sqlite3changeset_apply] 12585 ** <tr><td>sqlite3changeset_apply_strm_v2<td>[sqlite3changeset_apply_v2] 12586 ** <tr><td>sqlite3changeset_concat_strm<td>[sqlite3changeset_concat] 12587 ** <tr><td>sqlite3changeset_invert_strm<td>[sqlite3changeset_invert] 12588 ** <tr><td>sqlite3changeset_start_strm<td>[sqlite3changeset_start] 12589 ** <tr><td>sqlite3session_changeset_strm<td>[sqlite3session_changeset] 12590 ** <tr><td>sqlite3session_patchset_strm<td>[sqlite3session_patchset] 12591 ** </table> 12592 ** 12593 ** Non-streaming functions that accept changesets (or patchsets) as input 12594 ** require that the entire changeset be stored in a single buffer in memory. 12595 ** Similarly, those that return a changeset or patchset do so by returning 12596 ** a pointer to a single large buffer allocated using sqlite3_malloc(). 12597 ** Normally this is convenient. However, if an application running in a 12598 ** low-memory environment is required to handle very large changesets, the 12599 ** large contiguous memory allocations required can become onerous. 12600 ** 12601 ** In order to avoid this problem, instead of a single large buffer, input 12602 ** is passed to a streaming API functions by way of a callback function that 12603 ** the sessions module invokes to incrementally request input data as it is 12604 ** required. In all cases, a pair of API function parameters such as 12605 ** 12606 ** <pre> 12607 ** int nChangeset, 12608 ** void *pChangeset, 12609 ** </pre> 12610 ** 12611 ** Is replaced by: 12612 ** 12613 ** <pre> 12614 ** int (*xInput)(void *pIn, void *pData, int *pnData), 12615 ** void *pIn, 12616 ** </pre> 12617 ** 12618 ** Each time the xInput callback is invoked by the sessions module, the first 12619 ** argument passed is a copy of the supplied pIn context pointer. The second 12620 ** argument, pData, points to a buffer (*pnData) bytes in size. Assuming no 12621 ** error occurs the xInput method should copy up to (*pnData) bytes of data 12622 ** into the buffer and set (*pnData) to the actual number of bytes copied 12623 ** before returning SQLITE_OK. If the input is completely exhausted, (*pnData) 12624 ** should be set to zero to indicate this. Or, if an error occurs, an SQLite 12625 ** error code should be returned. In all cases, if an xInput callback returns 12626 ** an error, all processing is abandoned and the streaming API function 12627 ** returns a copy of the error code to the caller. 12628 ** 12629 ** In the case of sqlite3changeset_start_strm(), the xInput callback may be 12630 ** invoked by the sessions module at any point during the lifetime of the 12631 ** iterator. If such an xInput callback returns an error, the iterator enters 12632 ** an error state, whereby all subsequent calls to iterator functions 12633 ** immediately fail with the same error code as returned by xInput. 12634 ** 12635 ** Similarly, streaming API functions that return changesets (or patchsets) 12636 ** return them in chunks by way of a callback function instead of via a 12637 ** pointer to a single large buffer. In this case, a pair of parameters such 12638 ** as: 12639 ** 12640 ** <pre> 12641 ** int *pnChangeset, 12642 ** void **ppChangeset, 12643 ** </pre> 12644 ** 12645 ** Is replaced by: 12646 ** 12647 ** <pre> 12648 ** int (*xOutput)(void *pOut, const void *pData, int nData), 12649 ** void *pOut 12650 ** </pre> 12651 ** 12652 ** The xOutput callback is invoked zero or more times to return data to 12653 ** the application. The first parameter passed to each call is a copy of the 12654 ** pOut pointer supplied by the application. The second parameter, pData, 12655 ** points to a buffer nData bytes in size containing the chunk of output 12656 ** data being returned. If the xOutput callback successfully processes the 12657 ** supplied data, it should return SQLITE_OK to indicate success. Otherwise, 12658 ** it should return some other SQLite error code. In this case processing 12659 ** is immediately abandoned and the streaming API function returns a copy 12660 ** of the xOutput error code to the application. 12661 ** 12662 ** The sessions module never invokes an xOutput callback with the third 12663 ** parameter set to a value less than or equal to zero. Other than this, 12664 ** no guarantees are made as to the size of the chunks of data returned. 12665 */ 12666 SQLITE_API int sqlite3changeset_apply_strm( 12667 sqlite3 *db, /* Apply change to "main" db of this handle */ 12668 int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */ 12669 void *pIn, /* First arg for xInput */ 12670 int(*xFilter)( 12671 void *pCtx, /* Copy of sixth arg to _apply() */ 12672 const char *zTab /* Table name */ 12673 ), 12674 int(*xConflict)( 12675 void *pCtx, /* Copy of sixth arg to _apply() */ 12676 int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ 12677 sqlite3_changeset_iter *p /* Handle describing change and conflict */ 12678 ), 12679 void *pCtx /* First argument passed to xConflict */ 12680 ); 12681 SQLITE_API int sqlite3changeset_apply_v2_strm( 12682 sqlite3 *db, /* Apply change to "main" db of this handle */ 12683 int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */ 12684 void *pIn, /* First arg for xInput */ 12685 int(*xFilter)( 12686 void *pCtx, /* Copy of sixth arg to _apply() */ 12687 const char *zTab /* Table name */ 12688 ), 12689 int(*xConflict)( 12690 void *pCtx, /* Copy of sixth arg to _apply() */ 12691 int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ 12692 sqlite3_changeset_iter *p /* Handle describing change and conflict */ 12693 ), 12694 void *pCtx, /* First argument passed to xConflict */ 12695 void **ppRebase, int *pnRebase, 12696 int flags 12697 ); 12698 SQLITE_API int sqlite3changeset_concat_strm( 12699 int (*xInputA)(void *pIn, void *pData, int *pnData), 12700 void *pInA, 12701 int (*xInputB)(void *pIn, void *pData, int *pnData), 12702 void *pInB, 12703 int (*xOutput)(void *pOut, const void *pData, int nData), 12704 void *pOut 12705 ); 12706 SQLITE_API int sqlite3changeset_invert_strm( 12707 int (*xInput)(void *pIn, void *pData, int *pnData), 12708 void *pIn, 12709 int (*xOutput)(void *pOut, const void *pData, int nData), 12710 void *pOut 12711 ); 12712 SQLITE_API int sqlite3changeset_start_strm( 12713 sqlite3_changeset_iter **pp, 12714 int (*xInput)(void *pIn, void *pData, int *pnData), 12715 void *pIn 12716 ); 12717 SQLITE_API int sqlite3changeset_start_v2_strm( 12718 sqlite3_changeset_iter **pp, 12719 int (*xInput)(void *pIn, void *pData, int *pnData), 12720 void *pIn, 12721 int flags 12722 ); 12723 SQLITE_API int sqlite3session_changeset_strm( 12724 sqlite3_session *pSession, 12725 int (*xOutput)(void *pOut, const void *pData, int nData), 12726 void *pOut 12727 ); 12728 SQLITE_API int sqlite3session_patchset_strm( 12729 sqlite3_session *pSession, 12730 int (*xOutput)(void *pOut, const void *pData, int nData), 12731 void *pOut 12732 ); 12733 SQLITE_API int sqlite3changegroup_add_strm(sqlite3_changegroup*, 12734 int (*xInput)(void *pIn, void *pData, int *pnData), 12735 void *pIn 12736 ); 12737 SQLITE_API int sqlite3changegroup_output_strm(sqlite3_changegroup*, 12738 int (*xOutput)(void *pOut, const void *pData, int nData), 12739 void *pOut 12740 ); 12741 SQLITE_API int sqlite3rebaser_rebase_strm( 12742 sqlite3_rebaser *pRebaser, 12743 int (*xInput)(void *pIn, void *pData, int *pnData), 12744 void *pIn, 12745 int (*xOutput)(void *pOut, const void *pData, int nData), 12746 void *pOut 12747 ); 12748 12749 /* 12750 ** CAPI3REF: Configure global parameters 12751 ** 12752 ** The sqlite3session_config() interface is used to make global configuration 12753 ** changes to the sessions module in order to tune it to the specific needs 12754 ** of the application. 12755 ** 12756 ** The sqlite3session_config() interface is not threadsafe. If it is invoked 12757 ** while any other thread is inside any other sessions method then the 12758 ** results are undefined. Furthermore, if it is invoked after any sessions 12759 ** related objects have been created, the results are also undefined. 12760 ** 12761 ** The first argument to the sqlite3session_config() function must be one 12762 ** of the SQLITE_SESSION_CONFIG_XXX constants defined below. The 12763 ** interpretation of the (void*) value passed as the second parameter and 12764 ** the effect of calling this function depends on the value of the first 12765 ** parameter. 12766 ** 12767 ** <dl> 12768 ** <dt>SQLITE_SESSION_CONFIG_STRMSIZE<dd> 12769 ** By default, the sessions module streaming interfaces attempt to input 12770 ** and output data in approximately 1 KiB chunks. This operand may be used 12771 ** to set and query the value of this configuration setting. The pointer 12772 ** passed as the second argument must point to a value of type (int). 12773 ** If this value is greater than 0, it is used as the new streaming data 12774 ** chunk size for both input and output. Before returning, the (int) value 12775 ** pointed to by pArg is set to the final value of the streaming interface 12776 ** chunk size. 12777 ** </dl> 12778 ** 12779 ** This function returns SQLITE_OK if successful, or an SQLite error code 12780 ** otherwise. 12781 */ 12782 SQLITE_API int sqlite3session_config(int op, void *pArg); 12783 12784 /* 12785 ** CAPI3REF: Values for sqlite3session_config(). 12786 */ 12787 #define SQLITE_SESSION_CONFIG_STRMSIZE 1 12788 12789 /* 12790 ** Make sure we can call this stuff from C++. 12791 */ 12792 #ifdef __cplusplus 12793 } 12794 #endif 12795 12796 #endif /* !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) */ 12797 12798 /******** End of sqlite3session.h *********/ 12799 /******** Begin file fts5.h *********/ 12800 /* 12801 ** 2014 May 31 12802 ** 12803 ** The author disclaims copyright to this source code. In place of 12804 ** a legal notice, here is a blessing: 12805 ** 12806 ** May you do good and not evil. 12807 ** May you find forgiveness for yourself and forgive others. 12808 ** May you share freely, never taking more than you give. 12809 ** 12810 ****************************************************************************** 12811 ** 12812 ** Interfaces to extend FTS5. Using the interfaces defined in this file, 12813 ** FTS5 may be extended with: 12814 ** 12815 ** * custom tokenizers, and 12816 ** * custom auxiliary functions. 12817 */ 12818 12819 12820 #ifndef _FTS5_H 12821 #define _FTS5_H 12822 12823 12824 #ifdef __cplusplus 12825 extern "C" { 12826 #endif 12827 12828 /************************************************************************* 12829 ** CUSTOM AUXILIARY FUNCTIONS 12830 ** 12831 ** Virtual table implementations may overload SQL functions by implementing 12832 ** the sqlite3_module.xFindFunction() method. 12833 */ 12834 12835 typedef struct Fts5ExtensionApi Fts5ExtensionApi; 12836 typedef struct Fts5Context Fts5Context; 12837 typedef struct Fts5PhraseIter Fts5PhraseIter; 12838 12839 typedef void (*fts5_extension_function)( 12840 const Fts5ExtensionApi *pApi, /* API offered by current FTS version */ 12841 Fts5Context *pFts, /* First arg to pass to pApi functions */ 12842 sqlite3_context *pCtx, /* Context for returning result/error */ 12843 int nVal, /* Number of values in apVal[] array */ 12844 sqlite3_value **apVal /* Array of trailing arguments */ 12845 ); 12846 12847 struct Fts5PhraseIter { 12848 const unsigned char *a; 12849 const unsigned char *b; 12850 }; 12851 12852 /* 12853 ** EXTENSION API FUNCTIONS 12854 ** 12855 ** xUserData(pFts): 12856 ** Return a copy of the pUserData pointer passed to the xCreateFunction() 12857 ** API when the extension function was registered. 12858 ** 12859 ** xColumnTotalSize(pFts, iCol, pnToken): 12860 ** If parameter iCol is less than zero, set output variable *pnToken 12861 ** to the total number of tokens in the FTS5 table. Or, if iCol is 12862 ** non-negative but less than the number of columns in the table, return 12863 ** the total number of tokens in column iCol, considering all rows in 12864 ** the FTS5 table. 12865 ** 12866 ** If parameter iCol is greater than or equal to the number of columns 12867 ** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g. 12868 ** an OOM condition or IO error), an appropriate SQLite error code is 12869 ** returned. 12870 ** 12871 ** xColumnCount(pFts): 12872 ** Return the number of columns in the table. 12873 ** 12874 ** xColumnSize(pFts, iCol, pnToken): 12875 ** If parameter iCol is less than zero, set output variable *pnToken 12876 ** to the total number of tokens in the current row. Or, if iCol is 12877 ** non-negative but less than the number of columns in the table, set 12878 ** *pnToken to the number of tokens in column iCol of the current row. 12879 ** 12880 ** If parameter iCol is greater than or equal to the number of columns 12881 ** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g. 12882 ** an OOM condition or IO error), an appropriate SQLite error code is 12883 ** returned. 12884 ** 12885 ** This function may be quite inefficient if used with an FTS5 table 12886 ** created with the "columnsize=0" option. 12887 ** 12888 ** xColumnText: 12889 ** If parameter iCol is less than zero, or greater than or equal to the 12890 ** number of columns in the table, SQLITE_RANGE is returned. 12891 ** 12892 ** Otherwise, this function attempts to retrieve the text of column iCol of 12893 ** the current document. If successful, (*pz) is set to point to a buffer 12894 ** containing the text in utf-8 encoding, (*pn) is set to the size in bytes 12895 ** (not characters) of the buffer and SQLITE_OK is returned. Otherwise, 12896 ** if an error occurs, an SQLite error code is returned and the final values 12897 ** of (*pz) and (*pn) are undefined. 12898 ** 12899 ** xPhraseCount: 12900 ** Returns the number of phrases in the current query expression. 12901 ** 12902 ** xPhraseSize: 12903 ** If parameter iCol is less than zero, or greater than or equal to the 12904 ** number of phrases in the current query, as returned by xPhraseCount, 12905 ** 0 is returned. Otherwise, this function returns the number of tokens in 12906 ** phrase iPhrase of the query. Phrases are numbered starting from zero. 12907 ** 12908 ** xInstCount: 12909 ** Set *pnInst to the total number of occurrences of all phrases within 12910 ** the query within the current row. Return SQLITE_OK if successful, or 12911 ** an error code (i.e. SQLITE_NOMEM) if an error occurs. 12912 ** 12913 ** This API can be quite slow if used with an FTS5 table created with the 12914 ** "detail=none" or "detail=column" option. If the FTS5 table is created 12915 ** with either "detail=none" or "detail=column" and "content=" option 12916 ** (i.e. if it is a contentless table), then this API always returns 0. 12917 ** 12918 ** xInst: 12919 ** Query for the details of phrase match iIdx within the current row. 12920 ** Phrase matches are numbered starting from zero, so the iIdx argument 12921 ** should be greater than or equal to zero and smaller than the value 12922 ** output by xInstCount(). If iIdx is less than zero or greater than 12923 ** or equal to the value returned by xInstCount(), SQLITE_RANGE is returned. 12924 ** 12925 ** Otherwise, output parameter *piPhrase is set to the phrase number, *piCol 12926 ** to the column in which it occurs and *piOff the token offset of the 12927 ** first token of the phrase. SQLITE_OK is returned if successful, or an 12928 ** error code (i.e. SQLITE_NOMEM) if an error occurs. 12929 ** 12930 ** This API can be quite slow if used with an FTS5 table created with the 12931 ** "detail=none" or "detail=column" option. 12932 ** 12933 ** xRowid: 12934 ** Returns the rowid of the current row. 12935 ** 12936 ** xTokenize: 12937 ** Tokenize text using the tokenizer belonging to the FTS5 table. 12938 ** 12939 ** xQueryPhrase(pFts5, iPhrase, pUserData, xCallback): 12940 ** This API function is used to query the FTS table for phrase iPhrase 12941 ** of the current query. Specifically, a query equivalent to: 12942 ** 12943 ** ... FROM ftstable WHERE ftstable MATCH $p ORDER BY rowid 12944 ** 12945 ** with $p set to a phrase equivalent to the phrase iPhrase of the 12946 ** current query is executed. Any column filter that applies to 12947 ** phrase iPhrase of the current query is included in $p. For each 12948 ** row visited, the callback function passed as the fourth argument 12949 ** is invoked. The context and API objects passed to the callback 12950 ** function may be used to access the properties of each matched row. 12951 ** Invoking Api.xUserData() returns a copy of the pointer passed as 12952 ** the third argument to pUserData. 12953 ** 12954 ** If parameter iPhrase is less than zero, or greater than or equal to 12955 ** the number of phrases in the query, as returned by xPhraseCount(), 12956 ** this function returns SQLITE_RANGE. 12957 ** 12958 ** If the callback function returns any value other than SQLITE_OK, the 12959 ** query is abandoned and the xQueryPhrase function returns immediately. 12960 ** If the returned value is SQLITE_DONE, xQueryPhrase returns SQLITE_OK. 12961 ** Otherwise, the error code is propagated upwards. 12962 ** 12963 ** If the query runs to completion without incident, SQLITE_OK is returned. 12964 ** Or, if some error occurs before the query completes or is aborted by 12965 ** the callback, an SQLite error code is returned. 12966 ** 12967 ** 12968 ** xSetAuxdata(pFts5, pAux, xDelete) 12969 ** 12970 ** Save the pointer passed as the second argument as the extension function's 12971 ** "auxiliary data". The pointer may then be retrieved by the current or any 12972 ** future invocation of the same fts5 extension function made as part of 12973 ** the same MATCH query using the xGetAuxdata() API. 12974 ** 12975 ** Each extension function is allocated a single auxiliary data slot for 12976 ** each FTS query (MATCH expression). If the extension function is invoked 12977 ** more than once for a single FTS query, then all invocations share a 12978 ** single auxiliary data context. 12979 ** 12980 ** If there is already an auxiliary data pointer when this function is 12981 ** invoked, then it is replaced by the new pointer. If an xDelete callback 12982 ** was specified along with the original pointer, it is invoked at this 12983 ** point. 12984 ** 12985 ** The xDelete callback, if one is specified, is also invoked on the 12986 ** auxiliary data pointer after the FTS5 query has finished. 12987 ** 12988 ** If an error (e.g. an OOM condition) occurs within this function, 12989 ** the auxiliary data is set to NULL and an error code returned. If the 12990 ** xDelete parameter was not NULL, it is invoked on the auxiliary data 12991 ** pointer before returning. 12992 ** 12993 ** 12994 ** xGetAuxdata(pFts5, bClear) 12995 ** 12996 ** Returns the current auxiliary data pointer for the fts5 extension 12997 ** function. See the xSetAuxdata() method for details. 12998 ** 12999 ** If the bClear argument is non-zero, then the auxiliary data is cleared 13000 ** (set to NULL) before this function returns. In this case the xDelete, 13001 ** if any, is not invoked. 13002 ** 13003 ** 13004 ** xRowCount(pFts5, pnRow) 13005 ** 13006 ** This function is used to retrieve the total number of rows in the table. 13007 ** In other words, the same value that would be returned by: 13008 ** 13009 ** SELECT count(*) FROM ftstable; 13010 ** 13011 ** xPhraseFirst() 13012 ** This function is used, along with type Fts5PhraseIter and the xPhraseNext 13013 ** method, to iterate through all instances of a single query phrase within 13014 ** the current row. This is the same information as is accessible via the 13015 ** xInstCount/xInst APIs. While the xInstCount/xInst APIs are more convenient 13016 ** to use, this API may be faster under some circumstances. To iterate 13017 ** through instances of phrase iPhrase, use the following code: 13018 ** 13019 ** Fts5PhraseIter iter; 13020 ** int iCol, iOff; 13021 ** for(pApi->xPhraseFirst(pFts, iPhrase, &iter, &iCol, &iOff); 13022 ** iCol>=0; 13023 ** pApi->xPhraseNext(pFts, &iter, &iCol, &iOff) 13024 ** ){ 13025 ** // An instance of phrase iPhrase at offset iOff of column iCol 13026 ** } 13027 ** 13028 ** The Fts5PhraseIter structure is defined above. Applications should not 13029 ** modify this structure directly - it should only be used as shown above 13030 ** with the xPhraseFirst() and xPhraseNext() API methods (and by 13031 ** xPhraseFirstColumn() and xPhraseNextColumn() as illustrated below). 13032 ** 13033 ** This API can be quite slow if used with an FTS5 table created with the 13034 ** "detail=none" or "detail=column" option. If the FTS5 table is created 13035 ** with either "detail=none" or "detail=column" and "content=" option 13036 ** (i.e. if it is a contentless table), then this API always iterates 13037 ** through an empty set (all calls to xPhraseFirst() set iCol to -1). 13038 ** 13039 ** xPhraseNext() 13040 ** See xPhraseFirst above. 13041 ** 13042 ** xPhraseFirstColumn() 13043 ** This function and xPhraseNextColumn() are similar to the xPhraseFirst() 13044 ** and xPhraseNext() APIs described above. The difference is that instead 13045 ** of iterating through all instances of a phrase in the current row, these 13046 ** APIs are used to iterate through the set of columns in the current row 13047 ** that contain one or more instances of a specified phrase. For example: 13048 ** 13049 ** Fts5PhraseIter iter; 13050 ** int iCol; 13051 ** for(pApi->xPhraseFirstColumn(pFts, iPhrase, &iter, &iCol); 13052 ** iCol>=0; 13053 ** pApi->xPhraseNextColumn(pFts, &iter, &iCol) 13054 ** ){ 13055 ** // Column iCol contains at least one instance of phrase iPhrase 13056 ** } 13057 ** 13058 ** This API can be quite slow if used with an FTS5 table created with the 13059 ** "detail=none" option. If the FTS5 table is created with either 13060 ** "detail=none" "content=" option (i.e. if it is a contentless table), 13061 ** then this API always iterates through an empty set (all calls to 13062 ** xPhraseFirstColumn() set iCol to -1). 13063 ** 13064 ** The information accessed using this API and its companion 13065 ** xPhraseFirstColumn() may also be obtained using xPhraseFirst/xPhraseNext 13066 ** (or xInst/xInstCount). The chief advantage of this API is that it is 13067 ** significantly more efficient than those alternatives when used with 13068 ** "detail=column" tables. 13069 ** 13070 ** xPhraseNextColumn() 13071 ** See xPhraseFirstColumn above. 13072 ** 13073 ** xQueryToken(pFts5, iPhrase, iToken, ppToken, pnToken) 13074 ** This is used to access token iToken of phrase iPhrase of the current 13075 ** query. Before returning, output parameter *ppToken is set to point 13076 ** to a buffer containing the requested token, and *pnToken to the 13077 ** size of this buffer in bytes. 13078 ** 13079 ** If iPhrase or iToken are less than zero, or if iPhrase is greater than 13080 ** or equal to the number of phrases in the query as reported by 13081 ** xPhraseCount(), or if iToken is equal to or greater than the number of 13082 ** tokens in the phrase, SQLITE_RANGE is returned and *ppToken and *pnToken 13083 are both zeroed. 13084 ** 13085 ** The output text is not a copy of the query text that specified the 13086 ** token. It is the output of the tokenizer module. For tokendata=1 13087 ** tables, this includes any embedded 0x00 and trailing data. 13088 ** 13089 ** xInstToken(pFts5, iIdx, iToken, ppToken, pnToken) 13090 ** This is used to access token iToken of phrase hit iIdx within the 13091 ** current row. If iIdx is less than zero or greater than or equal to the 13092 ** value returned by xInstCount(), SQLITE_RANGE is returned. Otherwise, 13093 ** output variable (*ppToken) is set to point to a buffer containing the 13094 ** matching document token, and (*pnToken) to the size of that buffer in 13095 ** bytes. This API is not available if the specified token matches a 13096 ** prefix query term. In that case both output variables are always set 13097 ** to 0. 13098 ** 13099 ** The output text is not a copy of the document text that was tokenized. 13100 ** It is the output of the tokenizer module. For tokendata=1 tables, this 13101 ** includes any embedded 0x00 and trailing data. 13102 ** 13103 ** This API can be quite slow if used with an FTS5 table created with the 13104 ** "detail=none" or "detail=column" option. 13105 */ 13106 struct Fts5ExtensionApi { 13107 int iVersion; /* Currently always set to 3 */ 13108 13109 void *(*xUserData)(Fts5Context*); 13110 13111 int (*xColumnCount)(Fts5Context*); 13112 int (*xRowCount)(Fts5Context*, sqlite3_int64 *pnRow); 13113 int (*xColumnTotalSize)(Fts5Context*, int iCol, sqlite3_int64 *pnToken); 13114 13115 int (*xTokenize)(Fts5Context*, 13116 const char *pText, int nText, /* Text to tokenize */ 13117 void *pCtx, /* Context passed to xToken() */ 13118 int (*xToken)(void*, int, const char*, int, int, int) /* Callback */ 13119 ); 13120 13121 int (*xPhraseCount)(Fts5Context*); 13122 int (*xPhraseSize)(Fts5Context*, int iPhrase); 13123 13124 int (*xInstCount)(Fts5Context*, int *pnInst); 13125 int (*xInst)(Fts5Context*, int iIdx, int *piPhrase, int *piCol, int *piOff); 13126 13127 sqlite3_int64 (*xRowid)(Fts5Context*); 13128 int (*xColumnText)(Fts5Context*, int iCol, const char **pz, int *pn); 13129 int (*xColumnSize)(Fts5Context*, int iCol, int *pnToken); 13130 13131 int (*xQueryPhrase)(Fts5Context*, int iPhrase, void *pUserData, 13132 int(*)(const Fts5ExtensionApi*,Fts5Context*,void*) 13133 ); 13134 int (*xSetAuxdata)(Fts5Context*, void *pAux, void(*xDelete)(void*)); 13135 void *(*xGetAuxdata)(Fts5Context*, int bClear); 13136 13137 int (*xPhraseFirst)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*, int*); 13138 void (*xPhraseNext)(Fts5Context*, Fts5PhraseIter*, int *piCol, int *piOff); 13139 13140 int (*xPhraseFirstColumn)(Fts5Context*, int iPhrase, Fts5PhraseIter*, int*); 13141 void (*xPhraseNextColumn)(Fts5Context*, Fts5PhraseIter*, int *piCol); 13142 13143 /* Below this point are iVersion>=3 only */ 13144 int (*xQueryToken)(Fts5Context*, 13145 int iPhrase, int iToken, 13146 const char **ppToken, int *pnToken 13147 ); 13148 int (*xInstToken)(Fts5Context*, int iIdx, int iToken, const char**, int*); 13149 }; 13150 13151 /* 13152 ** CUSTOM AUXILIARY FUNCTIONS 13153 *************************************************************************/ 13154 13155 /************************************************************************* 13156 ** CUSTOM TOKENIZERS 13157 ** 13158 ** Applications may also register custom tokenizer types. A tokenizer 13159 ** is registered by providing fts5 with a populated instance of the 13160 ** following structure. All structure methods must be defined, setting 13161 ** any member of the fts5_tokenizer struct to NULL leads to undefined 13162 ** behaviour. The structure methods are expected to function as follows: 13163 ** 13164 ** xCreate: 13165 ** This function is used to allocate and initialize a tokenizer instance. 13166 ** A tokenizer instance is required to actually tokenize text. 13167 ** 13168 ** The first argument passed to this function is a copy of the (void*) 13169 ** pointer provided by the application when the fts5_tokenizer object 13170 ** was registered with FTS5 (the third argument to xCreateTokenizer()). 13171 ** The second and third arguments are an array of nul-terminated strings 13172 ** containing the tokenizer arguments, if any, specified following the 13173 ** tokenizer name as part of the CREATE VIRTUAL TABLE statement used 13174 ** to create the FTS5 table. 13175 ** 13176 ** The final argument is an output variable. If successful, (*ppOut) 13177 ** should be set to point to the new tokenizer handle and SQLITE_OK 13178 ** returned. If an error occurs, some value other than SQLITE_OK should 13179 ** be returned. In this case, fts5 assumes that the final value of *ppOut 13180 ** is undefined. 13181 ** 13182 ** xDelete: 13183 ** This function is invoked to delete a tokenizer handle previously 13184 ** allocated using xCreate(). Fts5 guarantees that this function will 13185 ** be invoked exactly once for each successful call to xCreate(). 13186 ** 13187 ** xTokenize: 13188 ** This function is expected to tokenize the nText byte string indicated 13189 ** by argument pText. pText may or may not be nul-terminated. The first 13190 ** argument passed to this function is a pointer to an Fts5Tokenizer object 13191 ** returned by an earlier call to xCreate(). 13192 ** 13193 ** The second argument indicates the reason that FTS5 is requesting 13194 ** tokenization of the supplied text. This is always one of the following 13195 ** four values: 13196 ** 13197 ** <ul><li> <b>FTS5_TOKENIZE_DOCUMENT</b> - A document is being inserted into 13198 ** or removed from the FTS table. The tokenizer is being invoked to 13199 ** determine the set of tokens to add to (or delete from) the 13200 ** FTS index. 13201 ** 13202 ** <li> <b>FTS5_TOKENIZE_QUERY</b> - A MATCH query is being executed 13203 ** against the FTS index. The tokenizer is being called to tokenize 13204 ** a bareword or quoted string specified as part of the query. 13205 ** 13206 ** <li> <b>(FTS5_TOKENIZE_QUERY | FTS5_TOKENIZE_PREFIX)</b> - Same as 13207 ** FTS5_TOKENIZE_QUERY, except that the bareword or quoted string is 13208 ** followed by a "*" character, indicating that the last token 13209 ** returned by the tokenizer will be treated as a token prefix. 13210 ** 13211 ** <li> <b>FTS5_TOKENIZE_AUX</b> - The tokenizer is being invoked to 13212 ** satisfy an fts5_api.xTokenize() request made by an auxiliary 13213 ** function. Or an fts5_api.xColumnSize() request made by the same 13214 ** on a columnsize=0 database. 13215 ** </ul> 13216 ** 13217 ** For each token in the input string, the supplied callback xToken() must 13218 ** be invoked. The first argument to it should be a copy of the pointer 13219 ** passed as the second argument to xTokenize(). The third and fourth 13220 ** arguments are a pointer to a buffer containing the token text, and the 13221 ** size of the token in bytes. The 4th and 5th arguments are the byte offsets 13222 ** of the first byte of and first byte immediately following the text from 13223 ** which the token is derived within the input. 13224 ** 13225 ** The second argument passed to the xToken() callback ("tflags") should 13226 ** normally be set to 0. The exception is if the tokenizer supports 13227 ** synonyms. In this case see the discussion below for details. 13228 ** 13229 ** FTS5 assumes the xToken() callback is invoked for each token in the 13230 ** order that they occur within the input text. 13231 ** 13232 ** If an xToken() callback returns any value other than SQLITE_OK, then 13233 ** the tokenization should be abandoned and the xTokenize() method should 13234 ** immediately return a copy of the xToken() return value. Or, if the 13235 ** input buffer is exhausted, xTokenize() should return SQLITE_OK. Finally, 13236 ** if an error occurs with the xTokenize() implementation itself, it 13237 ** may abandon the tokenization and return any error code other than 13238 ** SQLITE_OK or SQLITE_DONE. 13239 ** 13240 ** SYNONYM SUPPORT 13241 ** 13242 ** Custom tokenizers may also support synonyms. Consider a case in which a 13243 ** user wishes to query for a phrase such as "first place". Using the 13244 ** built-in tokenizers, the FTS5 query 'first + place' will match instances 13245 ** of "first place" within the document set, but not alternative forms 13246 ** such as "1st place". In some applications, it would be better to match 13247 ** all instances of "first place" or "1st place" regardless of which form 13248 ** the user specified in the MATCH query text. 13249 ** 13250 ** There are several ways to approach this in FTS5: 13251 ** 13252 ** <ol><li> By mapping all synonyms to a single token. In this case, using 13253 ** the above example, this means that the tokenizer returns the 13254 ** same token for inputs "first" and "1st". Say that token is in 13255 ** fact "first", so that when the user inserts the document "I won 13256 ** 1st place" entries are added to the index for tokens "i", "won", 13257 ** "first" and "place". If the user then queries for '1st + place', 13258 ** the tokenizer substitutes "first" for "1st" and the query works 13259 ** as expected. 13260 ** 13261 ** <li> By querying the index for all synonyms of each query term 13262 ** separately. In this case, when tokenizing query text, the 13263 ** tokenizer may provide multiple synonyms for a single term 13264 ** within the document. FTS5 then queries the index for each 13265 ** synonym individually. For example, faced with the query: 13266 ** 13267 ** <codeblock> 13268 ** ... MATCH 'first place'</codeblock> 13269 ** 13270 ** the tokenizer offers both "1st" and "first" as synonyms for the 13271 ** first token in the MATCH query and FTS5 effectively runs a query 13272 ** similar to: 13273 ** 13274 ** <codeblock> 13275 ** ... MATCH '(first OR 1st) place'</codeblock> 13276 ** 13277 ** except that, for the purposes of auxiliary functions, the query 13278 ** still appears to contain just two phrases - "(first OR 1st)" 13279 ** being treated as a single phrase. 13280 ** 13281 ** <li> By adding multiple synonyms for a single term to the FTS index. 13282 ** Using this method, when tokenizing document text, the tokenizer 13283 ** provides multiple synonyms for each token. So that when a 13284 ** document such as "I won first place" is tokenized, entries are 13285 ** added to the FTS index for "i", "won", "first", "1st" and 13286 ** "place". 13287 ** 13288 ** This way, even if the tokenizer does not provide synonyms 13289 ** when tokenizing query text (it should not - to do so would be 13290 ** inefficient), it doesn't matter if the user queries for 13291 ** 'first + place' or '1st + place', as there are entries in the 13292 ** FTS index corresponding to both forms of the first token. 13293 ** </ol> 13294 ** 13295 ** Whether it is parsing document or query text, any call to xToken that 13296 ** specifies a <i>tflags</i> argument with the FTS5_TOKEN_COLOCATED bit 13297 ** is considered to supply a synonym for the previous token. For example, 13298 ** when parsing the document "I won first place", a tokenizer that supports 13299 ** synonyms would call xToken() 5 times, as follows: 13300 ** 13301 ** <codeblock> 13302 ** xToken(pCtx, 0, "i", 1, 0, 1); 13303 ** xToken(pCtx, 0, "won", 3, 2, 5); 13304 ** xToken(pCtx, 0, "first", 5, 6, 11); 13305 ** xToken(pCtx, FTS5_TOKEN_COLOCATED, "1st", 3, 6, 11); 13306 ** xToken(pCtx, 0, "place", 5, 12, 17); 13307 **</codeblock> 13308 ** 13309 ** It is an error to specify the FTS5_TOKEN_COLOCATED flag the first time 13310 ** xToken() is called. Multiple synonyms may be specified for a single token 13311 ** by making multiple calls to xToken(FTS5_TOKEN_COLOCATED) in sequence. 13312 ** There is no limit to the number of synonyms that may be provided for a 13313 ** single token. 13314 ** 13315 ** In many cases, method (1) above is the best approach. It does not add 13316 ** extra data to the FTS index or require FTS5 to query for multiple terms, 13317 ** so it is efficient in terms of disk space and query speed. However, it 13318 ** does not support prefix queries very well. If, as suggested above, the 13319 ** token "first" is substituted for "1st" by the tokenizer, then the query: 13320 ** 13321 ** <codeblock> 13322 ** ... MATCH '1s*'</codeblock> 13323 ** 13324 ** will not match documents that contain the token "1st" (as the tokenizer 13325 ** will probably not map "1s" to any prefix of "first"). 13326 ** 13327 ** For full prefix support, method (3) may be preferred. In this case, 13328 ** because the index contains entries for both "first" and "1st", prefix 13329 ** queries such as 'fi*' or '1s*' will match correctly. However, because 13330 ** extra entries are added to the FTS index, this method uses more space 13331 ** within the database. 13332 ** 13333 ** Method (2) offers a midpoint between (1) and (3). Using this method, 13334 ** a query such as '1s*' will match documents that contain the literal 13335 ** token "1st", but not "first" (assuming the tokenizer is not able to 13336 ** provide synonyms for prefixes). However, a non-prefix query like '1st' 13337 ** will match against "1st" and "first". This method does not require 13338 ** extra disk space, as no extra entries are added to the FTS index. 13339 ** On the other hand, it may require more CPU cycles to run MATCH queries, 13340 ** as separate queries of the FTS index are required for each synonym. 13341 ** 13342 ** When using methods (2) or (3), it is important that the tokenizer only 13343 ** provide synonyms when tokenizing document text (method (3)) or query 13344 ** text (method (2)), not both. Doing so will not cause any errors, but is 13345 ** inefficient. 13346 */ 13347 typedef struct Fts5Tokenizer Fts5Tokenizer; 13348 typedef struct fts5_tokenizer fts5_tokenizer; 13349 struct fts5_tokenizer { 13350 int (*xCreate)(void*, const char **azArg, int nArg, Fts5Tokenizer **ppOut); 13351 void (*xDelete)(Fts5Tokenizer*); 13352 int (*xTokenize)(Fts5Tokenizer*, 13353 void *pCtx, 13354 int flags, /* Mask of FTS5_TOKENIZE_* flags */ 13355 const char *pText, int nText, 13356 int (*xToken)( 13357 void *pCtx, /* Copy of 2nd argument to xTokenize() */ 13358 int tflags, /* Mask of FTS5_TOKEN_* flags */ 13359 const char *pToken, /* Pointer to buffer containing token */ 13360 int nToken, /* Size of token in bytes */ 13361 int iStart, /* Byte offset of token within input text */ 13362 int iEnd /* Byte offset of end of token within input text */ 13363 ) 13364 ); 13365 }; 13366 13367 /* Flags that may be passed as the third argument to xTokenize() */ 13368 #define FTS5_TOKENIZE_QUERY 0x0001 13369 #define FTS5_TOKENIZE_PREFIX 0x0002 13370 #define FTS5_TOKENIZE_DOCUMENT 0x0004 13371 #define FTS5_TOKENIZE_AUX 0x0008 13372 13373 /* Flags that may be passed by the tokenizer implementation back to FTS5 13374 ** as the third argument to the supplied xToken callback. */ 13375 #define FTS5_TOKEN_COLOCATED 0x0001 /* Same position as prev. token */ 13376 13377 /* 13378 ** END OF CUSTOM TOKENIZERS 13379 *************************************************************************/ 13380 13381 /************************************************************************* 13382 ** FTS5 EXTENSION REGISTRATION API 13383 */ 13384 typedef struct fts5_api fts5_api; 13385 struct fts5_api { 13386 int iVersion; /* Currently always set to 2 */ 13387 13388 /* Create a new tokenizer */ 13389 int (*xCreateTokenizer)( 13390 fts5_api *pApi, 13391 const char *zName, 13392 void *pUserData, 13393 fts5_tokenizer *pTokenizer, 13394 void (*xDestroy)(void*) 13395 ); 13396 13397 /* Find an existing tokenizer */ 13398 int (*xFindTokenizer)( 13399 fts5_api *pApi, 13400 const char *zName, 13401 void **ppUserData, 13402 fts5_tokenizer *pTokenizer 13403 ); 13404 13405 /* Create a new auxiliary function */ 13406 int (*xCreateFunction)( 13407 fts5_api *pApi, 13408 const char *zName, 13409 void *pUserData, 13410 fts5_extension_function xFunction, 13411 void (*xDestroy)(void*) 13412 ); 13413 }; 13414 13415 /* 13416 ** END OF REGISTRATION API 13417 *************************************************************************/ 13418 13419 #ifdef __cplusplus 13420 } /* end of the 'extern "C"' block */ 13421 #endif 13422 13423 #endif /* _FTS5_H */ 13424 13425 /******** End of fts5.h *********/ 13426