1 2 #if !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) 3 #define __SQLITESESSION_H_ 1 4 5 /* 6 ** Make sure we can call this stuff from C++. 7 */ 8 #ifdef __cplusplus 9 extern "C" { 10 #endif 11 12 #include "sqlite3.h" 13 14 /* 15 ** CAPI3REF: Session Object Handle 16 ** 17 ** An instance of this object is a [session] that can be used to 18 ** record changes to a database. 19 */ 20 typedef struct sqlite3_session sqlite3_session; 21 22 /* 23 ** CAPI3REF: Changeset Iterator Handle 24 ** 25 ** An instance of this object acts as a cursor for iterating 26 ** over the elements of a [changeset] or [patchset]. 27 */ 28 typedef struct sqlite3_changeset_iter sqlite3_changeset_iter; 29 30 /* 31 ** CAPI3REF: Create A New Session Object 32 ** CONSTRUCTOR: sqlite3_session 33 ** 34 ** Create a new session object attached to database handle db. If successful, 35 ** a pointer to the new object is written to *ppSession and SQLITE_OK is 36 ** returned. If an error occurs, *ppSession is set to NULL and an SQLite 37 ** error code (e.g. SQLITE_NOMEM) is returned. 38 ** 39 ** It is possible to create multiple session objects attached to a single 40 ** database handle. 41 ** 42 ** Session objects created using this function should be deleted using the 43 ** [sqlite3session_delete()] function before the database handle that they 44 ** are attached to is itself closed. If the database handle is closed before 45 ** the session object is deleted, then the results of calling any session 46 ** module function, including [sqlite3session_delete()] on the session object 47 ** are undefined. 48 ** 49 ** Because the session module uses the [sqlite3_preupdate_hook()] API, it 50 ** is not possible for an application to register a pre-update hook on a 51 ** database handle that has one or more session objects attached. Nor is 52 ** it possible to create a session object attached to a database handle for 53 ** which a pre-update hook is already defined. The results of attempting 54 ** either of these things are undefined. 55 ** 56 ** The session object will be used to create changesets for tables in 57 ** database zDb, where zDb is either "main", or "temp", or the name of an 58 ** attached database. It is not an error if database zDb is not attached 59 ** to the database when the session object is created. 60 */ 61 int sqlite3session_create( 62 sqlite3 *db, /* Database handle */ 63 const char *zDb, /* Name of db (e.g. "main") */ 64 sqlite3_session **ppSession /* OUT: New session object */ 65 ); 66 67 /* 68 ** CAPI3REF: Delete A Session Object 69 ** DESTRUCTOR: sqlite3_session 70 ** 71 ** Delete a session object previously allocated using 72 ** [sqlite3session_create()]. Once a session object has been deleted, the 73 ** results of attempting to use pSession with any other session module 74 ** function are undefined. 75 ** 76 ** Session objects must be deleted before the database handle to which they 77 ** are attached is closed. Refer to the documentation for 78 ** [sqlite3session_create()] for details. 79 */ 80 void sqlite3session_delete(sqlite3_session *pSession); 81 82 83 /* 84 ** CAPI3REF: Enable Or Disable A Session Object 85 ** METHOD: sqlite3_session 86 ** 87 ** Enable or disable the recording of changes by a session object. When 88 ** enabled, a session object records changes made to the database. When 89 ** disabled - it does not. A newly created session object is enabled. 90 ** Refer to the documentation for [sqlite3session_changeset()] for further 91 ** details regarding how enabling and disabling a session object affects 92 ** the eventual changesets. 93 ** 94 ** Passing zero to this function disables the session. Passing a value 95 ** greater than zero enables it. Passing a value less than zero is a 96 ** no-op, and may be used to query the current state of the session. 97 ** 98 ** The return value indicates the final state of the session object: 0 if 99 ** the session is disabled, or 1 if it is enabled. 100 */ 101 int sqlite3session_enable(sqlite3_session *pSession, int bEnable); 102 103 /* 104 ** CAPI3REF: Set Or Clear the Indirect Change Flag 105 ** METHOD: sqlite3_session 106 ** 107 ** Each change recorded by a session object is marked as either direct or 108 ** indirect. A change is marked as indirect if either: 109 ** 110 ** <ul> 111 ** <li> The session object "indirect" flag is set when the change is 112 ** made, or 113 ** <li> The change is made by an SQL trigger or foreign key action 114 ** instead of directly as a result of a users SQL statement. 115 ** </ul> 116 ** 117 ** If a single row is affected by more than one operation within a session, 118 ** then the change is considered indirect if all operations meet the criteria 119 ** for an indirect change above, or direct otherwise. 120 ** 121 ** This function is used to set, clear or query the session object indirect 122 ** flag. If the second argument passed to this function is zero, then the 123 ** indirect flag is cleared. If it is greater than zero, the indirect flag 124 ** is set. Passing a value less than zero does not modify the current value 125 ** of the indirect flag, and may be used to query the current state of the 126 ** indirect flag for the specified session object. 127 ** 128 ** The return value indicates the final state of the indirect flag: 0 if 129 ** it is clear, or 1 if it is set. 130 */ 131 int sqlite3session_indirect(sqlite3_session *pSession, int bIndirect); 132 133 /* 134 ** CAPI3REF: Attach A Table To A Session Object 135 ** METHOD: sqlite3_session 136 ** 137 ** If argument zTab is not NULL, then it is the name of a table to attach 138 ** to the session object passed as the first argument. All subsequent changes 139 ** made to the table while the session object is enabled will be recorded. See 140 ** documentation for [sqlite3session_changeset()] for further details. 141 ** 142 ** Or, if argument zTab is NULL, then changes are recorded for all tables 143 ** in the database. If additional tables are added to the database (by 144 ** executing "CREATE TABLE" statements) after this call is made, changes for 145 ** the new tables are also recorded. 146 ** 147 ** Changes can only be recorded for tables that have a PRIMARY KEY explicitly 148 ** defined as part of their CREATE TABLE statement. It does not matter if the 149 ** PRIMARY KEY is an "INTEGER PRIMARY KEY" (rowid alias) or not. The PRIMARY 150 ** KEY may consist of a single column, or may be a composite key. 151 ** 152 ** It is not an error if the named table does not exist in the database. Nor 153 ** is it an error if the named table does not have a PRIMARY KEY. However, 154 ** no changes will be recorded in either of these scenarios. 155 ** 156 ** Changes are not recorded for individual rows that have NULL values stored 157 ** in one or more of their PRIMARY KEY columns. 158 ** 159 ** SQLITE_OK is returned if the call completes without error. Or, if an error 160 ** occurs, an SQLite error code (e.g. SQLITE_NOMEM) is returned. 161 ** 162 ** <h3>Special sqlite_stat1 Handling</h3> 163 ** 164 ** As of SQLite version 3.22.0, the "sqlite_stat1" table is an exception to 165 ** some of the rules above. In SQLite, the schema of sqlite_stat1 is: 166 ** <pre> 167 ** CREATE TABLE sqlite_stat1(tbl,idx,stat) 168 ** </pre> 169 ** 170 ** Even though sqlite_stat1 does not have a PRIMARY KEY, changes are 171 ** recorded for it as if the PRIMARY KEY is (tbl,idx). Additionally, changes 172 ** are recorded for rows for which (idx IS NULL) is true. However, for such 173 ** rows a zero-length blob (SQL value X'') is stored in the changeset or 174 ** patchset instead of a NULL value. This allows such changesets to be 175 ** manipulated by legacy implementations of sqlite3changeset_invert(), 176 ** concat() and similar. 177 ** 178 ** The sqlite3changeset_apply() function automatically converts the 179 ** zero-length blob back to a NULL value when updating the sqlite_stat1 180 ** table. However, if the application calls sqlite3changeset_new(), 181 ** sqlite3changeset_old() or sqlite3changeset_conflict on a changeset 182 ** iterator directly (including on a changeset iterator passed to a 183 ** conflict-handler callback) then the X'' value is returned. The application 184 ** must translate X'' to NULL itself if required. 185 ** 186 ** Legacy (older than 3.22.0) versions of the sessions module cannot capture 187 ** changes made to the sqlite_stat1 table. Legacy versions of the 188 ** sqlite3changeset_apply() function silently ignore any modifications to the 189 ** sqlite_stat1 table that are part of a changeset or patchset. 190 */ 191 int sqlite3session_attach( 192 sqlite3_session *pSession, /* Session object */ 193 const char *zTab /* Table name */ 194 ); 195 196 /* 197 ** CAPI3REF: Set a table filter on a Session Object. 198 ** METHOD: sqlite3_session 199 ** 200 ** The second argument (xFilter) is the "filter callback". For changes to rows 201 ** in tables that are not attached to the Session object, the filter is called 202 ** to determine whether changes to the table's rows should be tracked or not. 203 ** If xFilter returns 0, changes are not tracked. Note that once a table is 204 ** attached, xFilter will not be called again. 205 */ 206 void sqlite3session_table_filter( 207 sqlite3_session *pSession, /* Session object */ 208 int(*xFilter)( 209 void *pCtx, /* Copy of third arg to _filter_table() */ 210 const char *zTab /* Table name */ 211 ), 212 void *pCtx /* First argument passed to xFilter */ 213 ); 214 215 /* 216 ** CAPI3REF: Generate A Changeset From A Session Object 217 ** METHOD: sqlite3_session 218 ** 219 ** Obtain a changeset containing changes to the tables attached to the 220 ** session object passed as the first argument. If successful, 221 ** set *ppChangeset to point to a buffer containing the changeset 222 ** and *pnChangeset to the size of the changeset in bytes before returning 223 ** SQLITE_OK. If an error occurs, set both *ppChangeset and *pnChangeset to 224 ** zero and return an SQLite error code. 225 ** 226 ** A changeset consists of zero or more INSERT, UPDATE and/or DELETE changes, 227 ** each representing a change to a single row of an attached table. An INSERT 228 ** change contains the values of each field of a new database row. A DELETE 229 ** contains the original values of each field of a deleted database row. An 230 ** UPDATE change contains the original values of each field of an updated 231 ** database row along with the updated values for each updated non-primary-key 232 ** column. It is not possible for an UPDATE change to represent a change that 233 ** modifies the values of primary key columns. If such a change is made, it 234 ** is represented in a changeset as a DELETE followed by an INSERT. 235 ** 236 ** Changes are not recorded for rows that have NULL values stored in one or 237 ** more of their PRIMARY KEY columns. If such a row is inserted or deleted, 238 ** no corresponding change is present in the changesets returned by this 239 ** function. If an existing row with one or more NULL values stored in 240 ** PRIMARY KEY columns is updated so that all PRIMARY KEY columns are non-NULL, 241 ** only an INSERT is appears in the changeset. Similarly, if an existing row 242 ** with non-NULL PRIMARY KEY values is updated so that one or more of its 243 ** PRIMARY KEY columns are set to NULL, the resulting changeset contains a 244 ** DELETE change only. 245 ** 246 ** The contents of a changeset may be traversed using an iterator created 247 ** using the [sqlite3changeset_start()] API. A changeset may be applied to 248 ** a database with a compatible schema using the [sqlite3changeset_apply()] 249 ** API. 250 ** 251 ** Within a changeset generated by this function, all changes related to a 252 ** single table are grouped together. In other words, when iterating through 253 ** a changeset or when applying a changeset to a database, all changes related 254 ** to a single table are processed before moving on to the next table. Tables 255 ** are sorted in the same order in which they were attached (or auto-attached) 256 ** to the sqlite3_session object. The order in which the changes related to 257 ** a single table are stored is undefined. 258 ** 259 ** Following a successful call to this function, it is the responsibility of 260 ** the caller to eventually free the buffer that *ppChangeset points to using 261 ** [sqlite3_free()]. 262 ** 263 ** <h3>Changeset Generation</h3> 264 ** 265 ** Once a table has been attached to a session object, the session object 266 ** records the primary key values of all new rows inserted into the table. 267 ** It also records the original primary key and other column values of any 268 ** deleted or updated rows. For each unique primary key value, data is only 269 ** recorded once - the first time a row with said primary key is inserted, 270 ** updated or deleted in the lifetime of the session. 271 ** 272 ** There is one exception to the previous paragraph: when a row is inserted, 273 ** updated or deleted, if one or more of its primary key columns contain a 274 ** NULL value, no record of the change is made. 275 ** 276 ** The session object therefore accumulates two types of records - those 277 ** that consist of primary key values only (created when the user inserts 278 ** a new record) and those that consist of the primary key values and the 279 ** original values of other table columns (created when the users deletes 280 ** or updates a record). 281 ** 282 ** When this function is called, the requested changeset is created using 283 ** both the accumulated records and the current contents of the database 284 ** file. Specifically: 285 ** 286 ** <ul> 287 ** <li> For each record generated by an insert, the database is queried 288 ** for a row with a matching primary key. If one is found, an INSERT 289 ** change is added to the changeset. If no such row is found, no change 290 ** is added to the changeset. 291 ** 292 ** <li> For each record generated by an update or delete, the database is 293 ** queried for a row with a matching primary key. If such a row is 294 ** found and one or more of the non-primary key fields have been 295 ** modified from their original values, an UPDATE change is added to 296 ** the changeset. Or, if no such row is found in the table, a DELETE 297 ** change is added to the changeset. If there is a row with a matching 298 ** primary key in the database, but all fields contain their original 299 ** values, no change is added to the changeset. 300 ** </ul> 301 ** 302 ** This means, amongst other things, that if a row is inserted and then later 303 ** deleted while a session object is active, neither the insert nor the delete 304 ** will be present in the changeset. Or if a row is deleted and then later a 305 ** row with the same primary key values inserted while a session object is 306 ** active, the resulting changeset will contain an UPDATE change instead of 307 ** a DELETE and an INSERT. 308 ** 309 ** When a session object is disabled (see the [sqlite3session_enable()] API), 310 ** it does not accumulate records when rows are inserted, updated or deleted. 311 ** This may appear to have some counter-intuitive effects if a single row 312 ** is written to more than once during a session. For example, if a row 313 ** is inserted while a session object is enabled, then later deleted while 314 ** the same session object is disabled, no INSERT record will appear in the 315 ** changeset, even though the delete took place while the session was disabled. 316 ** Or, if one field of a row is updated while a session is disabled, and 317 ** another field of the same row is updated while the session is enabled, the 318 ** resulting changeset will contain an UPDATE change that updates both fields. 319 */ 320 int sqlite3session_changeset( 321 sqlite3_session *pSession, /* Session object */ 322 int *pnChangeset, /* OUT: Size of buffer at *ppChangeset */ 323 void **ppChangeset /* OUT: Buffer containing changeset */ 324 ); 325 326 /* 327 ** CAPI3REF: Load The Difference Between Tables Into A Session 328 ** METHOD: sqlite3_session 329 ** 330 ** If it is not already attached to the session object passed as the first 331 ** argument, this function attaches table zTbl in the same manner as the 332 ** [sqlite3session_attach()] function. If zTbl does not exist, or if it 333 ** does not have a primary key, this function is a no-op (but does not return 334 ** an error). 335 ** 336 ** Argument zFromDb must be the name of a database ("main", "temp" etc.) 337 ** attached to the same database handle as the session object that contains 338 ** a table compatible with the table attached to the session by this function. 339 ** A table is considered compatible if it: 340 ** 341 ** <ul> 342 ** <li> Has the same name, 343 ** <li> Has the same set of columns declared in the same order, and 344 ** <li> Has the same PRIMARY KEY definition. 345 ** </ul> 346 ** 347 ** If the tables are not compatible, SQLITE_SCHEMA is returned. If the tables 348 ** are compatible but do not have any PRIMARY KEY columns, it is not an error 349 ** but no changes are added to the session object. As with other session 350 ** APIs, tables without PRIMARY KEYs are simply ignored. 351 ** 352 ** This function adds a set of changes to the session object that could be 353 ** used to update the table in database zFrom (call this the "from-table") 354 ** so that its content is the same as the table attached to the session 355 ** object (call this the "to-table"). Specifically: 356 ** 357 ** <ul> 358 ** <li> For each row (primary key) that exists in the to-table but not in 359 ** the from-table, an INSERT record is added to the session object. 360 ** 361 ** <li> For each row (primary key) that exists in the to-table but not in 362 ** the from-table, a DELETE record is added to the session object. 363 ** 364 ** <li> For each row (primary key) that exists in both tables, but features 365 ** different non-PK values in each, an UPDATE record is added to the 366 ** session. 367 ** </ul> 368 ** 369 ** To clarify, if this function is called and then a changeset constructed 370 ** using [sqlite3session_changeset()], then after applying that changeset to 371 ** database zFrom the contents of the two compatible tables would be 372 ** identical. 373 ** 374 ** It an error if database zFrom does not exist or does not contain the 375 ** required compatible table. 376 ** 377 ** If the operation is successful, SQLITE_OK is returned. Otherwise, an SQLite 378 ** error code. In this case, if argument pzErrMsg is not NULL, *pzErrMsg 379 ** may be set to point to a buffer containing an English language error 380 ** message. It is the responsibility of the caller to free this buffer using 381 ** sqlite3_free(). 382 */ 383 int sqlite3session_diff( 384 sqlite3_session *pSession, 385 const char *zFromDb, 386 const char *zTbl, 387 char **pzErrMsg 388 ); 389 390 391 /* 392 ** CAPI3REF: Generate A Patchset From A Session Object 393 ** METHOD: sqlite3_session 394 ** 395 ** The differences between a patchset and a changeset are that: 396 ** 397 ** <ul> 398 ** <li> DELETE records consist of the primary key fields only. The 399 ** original values of other fields are omitted. 400 ** <li> The original values of any modified fields are omitted from 401 ** UPDATE records. 402 ** </ul> 403 ** 404 ** A patchset blob may be used with up to date versions of all 405 ** sqlite3changeset_xxx API functions except for sqlite3changeset_invert(), 406 ** which returns SQLITE_CORRUPT if it is passed a patchset. Similarly, 407 ** attempting to use a patchset blob with old versions of the 408 ** sqlite3changeset_xxx APIs also provokes an SQLITE_CORRUPT error. 409 ** 410 ** Because the non-primary key "old.*" fields are omitted, no 411 ** SQLITE_CHANGESET_DATA conflicts can be detected or reported if a patchset 412 ** is passed to the sqlite3changeset_apply() API. Other conflict types work 413 ** in the same way as for changesets. 414 ** 415 ** Changes within a patchset are ordered in the same way as for changesets 416 ** generated by the sqlite3session_changeset() function (i.e. all changes for 417 ** a single table are grouped together, tables appear in the order in which 418 ** they were attached to the session object). 419 */ 420 int sqlite3session_patchset( 421 sqlite3_session *pSession, /* Session object */ 422 int *pnPatchset, /* OUT: Size of buffer at *ppPatchset */ 423 void **ppPatchset /* OUT: Buffer containing patchset */ 424 ); 425 426 /* 427 ** CAPI3REF: Test if a changeset has recorded any changes. 428 ** 429 ** Return non-zero if no changes to attached tables have been recorded by 430 ** the session object passed as the first argument. Otherwise, if one or 431 ** more changes have been recorded, return zero. 432 ** 433 ** Even if this function returns zero, it is possible that calling 434 ** [sqlite3session_changeset()] on the session handle may still return a 435 ** changeset that contains no changes. This can happen when a row in 436 ** an attached table is modified and then later on the original values 437 ** are restored. However, if this function returns non-zero, then it is 438 ** guaranteed that a call to sqlite3session_changeset() will return a 439 ** changeset containing zero changes. 440 */ 441 int sqlite3session_isempty(sqlite3_session *pSession); 442 443 /* 444 ** CAPI3REF: Query for the amount of heap memory used by a session object. 445 ** 446 ** This API returns the total amount of heap memory in bytes currently 447 ** used by the session object passed as the only argument. 448 */ 449 sqlite3_int64 sqlite3session_memory_used(sqlite3_session *pSession); 450 451 /* 452 ** CAPI3REF: Create An Iterator To Traverse A Changeset 453 ** CONSTRUCTOR: sqlite3_changeset_iter 454 ** 455 ** Create an iterator used to iterate through the contents of a changeset. 456 ** If successful, *pp is set to point to the iterator handle and SQLITE_OK 457 ** is returned. Otherwise, if an error occurs, *pp is set to zero and an 458 ** SQLite error code is returned. 459 ** 460 ** The following functions can be used to advance and query a changeset 461 ** iterator created by this function: 462 ** 463 ** <ul> 464 ** <li> [sqlite3changeset_next()] 465 ** <li> [sqlite3changeset_op()] 466 ** <li> [sqlite3changeset_new()] 467 ** <li> [sqlite3changeset_old()] 468 ** </ul> 469 ** 470 ** It is the responsibility of the caller to eventually destroy the iterator 471 ** by passing it to [sqlite3changeset_finalize()]. The buffer containing the 472 ** changeset (pChangeset) must remain valid until after the iterator is 473 ** destroyed. 474 ** 475 ** Assuming the changeset blob was created by one of the 476 ** [sqlite3session_changeset()], [sqlite3changeset_concat()] or 477 ** [sqlite3changeset_invert()] functions, all changes within the changeset 478 ** that apply to a single table are grouped together. This means that when 479 ** an application iterates through a changeset using an iterator created by 480 ** this function, all changes that relate to a single table are visited 481 ** consecutively. There is no chance that the iterator will visit a change 482 ** the applies to table X, then one for table Y, and then later on visit 483 ** another change for table X. 484 ** 485 ** The behavior of sqlite3changeset_start_v2() and its streaming equivalent 486 ** may be modified by passing a combination of 487 ** [SQLITE_CHANGESETSTART_INVERT | supported flags] as the 4th parameter. 488 ** 489 ** Note that the sqlite3changeset_start_v2() API is still <b>experimental</b> 490 ** and therefore subject to change. 491 */ 492 int sqlite3changeset_start( 493 sqlite3_changeset_iter **pp, /* OUT: New changeset iterator handle */ 494 int nChangeset, /* Size of changeset blob in bytes */ 495 void *pChangeset /* Pointer to blob containing changeset */ 496 ); 497 int sqlite3changeset_start_v2( 498 sqlite3_changeset_iter **pp, /* OUT: New changeset iterator handle */ 499 int nChangeset, /* Size of changeset blob in bytes */ 500 void *pChangeset, /* Pointer to blob containing changeset */ 501 int flags /* SESSION_CHANGESETSTART_* flags */ 502 ); 503 504 /* 505 ** CAPI3REF: Flags for sqlite3changeset_start_v2 506 ** 507 ** The following flags may passed via the 4th parameter to 508 ** [sqlite3changeset_start_v2] and [sqlite3changeset_start_v2_strm]: 509 ** 510 ** <dt>SQLITE_CHANGESETAPPLY_INVERT <dd> 511 ** Invert the changeset while iterating through it. This is equivalent to 512 ** inverting a changeset using sqlite3changeset_invert() before applying it. 513 ** It is an error to specify this flag with a patchset. 514 */ 515 #define SQLITE_CHANGESETSTART_INVERT 0x0002 516 517 518 /* 519 ** CAPI3REF: Advance A Changeset Iterator 520 ** METHOD: sqlite3_changeset_iter 521 ** 522 ** This function may only be used with iterators created by the function 523 ** [sqlite3changeset_start()]. If it is called on an iterator passed to 524 ** a conflict-handler callback by [sqlite3changeset_apply()], SQLITE_MISUSE 525 ** is returned and the call has no effect. 526 ** 527 ** Immediately after an iterator is created by sqlite3changeset_start(), it 528 ** does not point to any change in the changeset. Assuming the changeset 529 ** is not empty, the first call to this function advances the iterator to 530 ** point to the first change in the changeset. Each subsequent call advances 531 ** the iterator to point to the next change in the changeset (if any). If 532 ** no error occurs and the iterator points to a valid change after a call 533 ** to sqlite3changeset_next() has advanced it, SQLITE_ROW is returned. 534 ** Otherwise, if all changes in the changeset have already been visited, 535 ** SQLITE_DONE is returned. 536 ** 537 ** If an error occurs, an SQLite error code is returned. Possible error 538 ** codes include SQLITE_CORRUPT (if the changeset buffer is corrupt) or 539 ** SQLITE_NOMEM. 540 */ 541 int sqlite3changeset_next(sqlite3_changeset_iter *pIter); 542 543 /* 544 ** CAPI3REF: Obtain The Current Operation From A Changeset Iterator 545 ** METHOD: sqlite3_changeset_iter 546 ** 547 ** The pIter argument passed to this function may either be an iterator 548 ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator 549 ** created by [sqlite3changeset_start()]. In the latter case, the most recent 550 ** call to [sqlite3changeset_next()] must have returned [SQLITE_ROW]. If this 551 ** is not the case, this function returns [SQLITE_MISUSE]. 552 ** 553 ** If argument pzTab is not NULL, then *pzTab is set to point to a 554 ** nul-terminated utf-8 encoded string containing the name of the table 555 ** affected by the current change. The buffer remains valid until either 556 ** sqlite3changeset_next() is called on the iterator or until the 557 ** conflict-handler function returns. If pnCol is not NULL, then *pnCol is 558 ** set to the number of columns in the table affected by the change. If 559 ** pbIndirect is not NULL, then *pbIndirect is set to true (1) if the change 560 ** is an indirect change, or false (0) otherwise. See the documentation for 561 ** [sqlite3session_indirect()] for a description of direct and indirect 562 ** changes. Finally, if pOp is not NULL, then *pOp is set to one of 563 ** [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE], depending on the 564 ** type of change that the iterator currently points to. 565 ** 566 ** If no error occurs, SQLITE_OK is returned. If an error does occur, an 567 ** SQLite error code is returned. The values of the output variables may not 568 ** be trusted in this case. 569 */ 570 int sqlite3changeset_op( 571 sqlite3_changeset_iter *pIter, /* Iterator object */ 572 const char **pzTab, /* OUT: Pointer to table name */ 573 int *pnCol, /* OUT: Number of columns in table */ 574 int *pOp, /* OUT: SQLITE_INSERT, DELETE or UPDATE */ 575 int *pbIndirect /* OUT: True for an 'indirect' change */ 576 ); 577 578 /* 579 ** CAPI3REF: Obtain The Primary Key Definition Of A Table 580 ** METHOD: sqlite3_changeset_iter 581 ** 582 ** For each modified table, a changeset includes the following: 583 ** 584 ** <ul> 585 ** <li> The number of columns in the table, and 586 ** <li> Which of those columns make up the tables PRIMARY KEY. 587 ** </ul> 588 ** 589 ** This function is used to find which columns comprise the PRIMARY KEY of 590 ** the table modified by the change that iterator pIter currently points to. 591 ** If successful, *pabPK is set to point to an array of nCol entries, where 592 ** nCol is the number of columns in the table. Elements of *pabPK are set to 593 ** 0x01 if the corresponding column is part of the tables primary key, or 594 ** 0x00 if it is not. 595 ** 596 ** If argument pnCol is not NULL, then *pnCol is set to the number of columns 597 ** in the table. 598 ** 599 ** If this function is called when the iterator does not point to a valid 600 ** entry, SQLITE_MISUSE is returned and the output variables zeroed. Otherwise, 601 ** SQLITE_OK is returned and the output variables populated as described 602 ** above. 603 */ 604 int sqlite3changeset_pk( 605 sqlite3_changeset_iter *pIter, /* Iterator object */ 606 unsigned char **pabPK, /* OUT: Array of boolean - true for PK cols */ 607 int *pnCol /* OUT: Number of entries in output array */ 608 ); 609 610 /* 611 ** CAPI3REF: Obtain old.* Values From A Changeset Iterator 612 ** METHOD: sqlite3_changeset_iter 613 ** 614 ** The pIter argument passed to this function may either be an iterator 615 ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator 616 ** created by [sqlite3changeset_start()]. In the latter case, the most recent 617 ** call to [sqlite3changeset_next()] must have returned SQLITE_ROW. 618 ** Furthermore, it may only be called if the type of change that the iterator 619 ** currently points to is either [SQLITE_DELETE] or [SQLITE_UPDATE]. Otherwise, 620 ** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL. 621 ** 622 ** Argument iVal must be greater than or equal to 0, and less than the number 623 ** of columns in the table affected by the current change. Otherwise, 624 ** [SQLITE_RANGE] is returned and *ppValue is set to NULL. 625 ** 626 ** If successful, this function sets *ppValue to point to a protected 627 ** sqlite3_value object containing the iVal'th value from the vector of 628 ** original row values stored as part of the UPDATE or DELETE change and 629 ** returns SQLITE_OK. The name of the function comes from the fact that this 630 ** is similar to the "old.*" columns available to update or delete triggers. 631 ** 632 ** If some other error occurs (e.g. an OOM condition), an SQLite error code 633 ** is returned and *ppValue is set to NULL. 634 */ 635 int sqlite3changeset_old( 636 sqlite3_changeset_iter *pIter, /* Changeset iterator */ 637 int iVal, /* Column number */ 638 sqlite3_value **ppValue /* OUT: Old value (or NULL pointer) */ 639 ); 640 641 /* 642 ** CAPI3REF: Obtain new.* Values From A Changeset Iterator 643 ** METHOD: sqlite3_changeset_iter 644 ** 645 ** The pIter argument passed to this function may either be an iterator 646 ** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator 647 ** created by [sqlite3changeset_start()]. In the latter case, the most recent 648 ** call to [sqlite3changeset_next()] must have returned SQLITE_ROW. 649 ** Furthermore, it may only be called if the type of change that the iterator 650 ** currently points to is either [SQLITE_UPDATE] or [SQLITE_INSERT]. Otherwise, 651 ** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL. 652 ** 653 ** Argument iVal must be greater than or equal to 0, and less than the number 654 ** of columns in the table affected by the current change. Otherwise, 655 ** [SQLITE_RANGE] is returned and *ppValue is set to NULL. 656 ** 657 ** If successful, this function sets *ppValue to point to a protected 658 ** sqlite3_value object containing the iVal'th value from the vector of 659 ** new row values stored as part of the UPDATE or INSERT change and 660 ** returns SQLITE_OK. If the change is an UPDATE and does not include 661 ** a new value for the requested column, *ppValue is set to NULL and 662 ** SQLITE_OK returned. The name of the function comes from the fact that 663 ** this is similar to the "new.*" columns available to update or delete 664 ** triggers. 665 ** 666 ** If some other error occurs (e.g. an OOM condition), an SQLite error code 667 ** is returned and *ppValue is set to NULL. 668 */ 669 int sqlite3changeset_new( 670 sqlite3_changeset_iter *pIter, /* Changeset iterator */ 671 int iVal, /* Column number */ 672 sqlite3_value **ppValue /* OUT: New value (or NULL pointer) */ 673 ); 674 675 /* 676 ** CAPI3REF: Obtain Conflicting Row Values From A Changeset Iterator 677 ** METHOD: sqlite3_changeset_iter 678 ** 679 ** This function should only be used with iterator objects passed to a 680 ** conflict-handler callback by [sqlite3changeset_apply()] with either 681 ** [SQLITE_CHANGESET_DATA] or [SQLITE_CHANGESET_CONFLICT]. If this function 682 ** is called on any other iterator, [SQLITE_MISUSE] is returned and *ppValue 683 ** is set to NULL. 684 ** 685 ** Argument iVal must be greater than or equal to 0, and less than the number 686 ** of columns in the table affected by the current change. Otherwise, 687 ** [SQLITE_RANGE] is returned and *ppValue is set to NULL. 688 ** 689 ** If successful, this function sets *ppValue to point to a protected 690 ** sqlite3_value object containing the iVal'th value from the 691 ** "conflicting row" associated with the current conflict-handler callback 692 ** and returns SQLITE_OK. 693 ** 694 ** If some other error occurs (e.g. an OOM condition), an SQLite error code 695 ** is returned and *ppValue is set to NULL. 696 */ 697 int sqlite3changeset_conflict( 698 sqlite3_changeset_iter *pIter, /* Changeset iterator */ 699 int iVal, /* Column number */ 700 sqlite3_value **ppValue /* OUT: Value from conflicting row */ 701 ); 702 703 /* 704 ** CAPI3REF: Determine The Number Of Foreign Key Constraint Violations 705 ** METHOD: sqlite3_changeset_iter 706 ** 707 ** This function may only be called with an iterator passed to an 708 ** SQLITE_CHANGESET_FOREIGN_KEY conflict handler callback. In this case 709 ** it sets the output variable to the total number of known foreign key 710 ** violations in the destination database and returns SQLITE_OK. 711 ** 712 ** In all other cases this function returns SQLITE_MISUSE. 713 */ 714 int sqlite3changeset_fk_conflicts( 715 sqlite3_changeset_iter *pIter, /* Changeset iterator */ 716 int *pnOut /* OUT: Number of FK violations */ 717 ); 718 719 720 /* 721 ** CAPI3REF: Finalize A Changeset Iterator 722 ** METHOD: sqlite3_changeset_iter 723 ** 724 ** This function is used to finalize an iterator allocated with 725 ** [sqlite3changeset_start()]. 726 ** 727 ** This function should only be called on iterators created using the 728 ** [sqlite3changeset_start()] function. If an application calls this 729 ** function with an iterator passed to a conflict-handler by 730 ** [sqlite3changeset_apply()], [SQLITE_MISUSE] is immediately returned and the 731 ** call has no effect. 732 ** 733 ** If an error was encountered within a call to an sqlite3changeset_xxx() 734 ** function (for example an [SQLITE_CORRUPT] in [sqlite3changeset_next()] or an 735 ** [SQLITE_NOMEM] in [sqlite3changeset_new()]) then an error code corresponding 736 ** to that error is returned by this function. Otherwise, SQLITE_OK is 737 ** returned. This is to allow the following pattern (pseudo-code): 738 ** 739 ** <pre> 740 ** sqlite3changeset_start(); 741 ** while( SQLITE_ROW==sqlite3changeset_next() ){ 742 ** // Do something with change. 743 ** } 744 ** rc = sqlite3changeset_finalize(); 745 ** if( rc!=SQLITE_OK ){ 746 ** // An error has occurred 747 ** } 748 ** </pre> 749 */ 750 int sqlite3changeset_finalize(sqlite3_changeset_iter *pIter); 751 752 /* 753 ** CAPI3REF: Invert A Changeset 754 ** 755 ** This function is used to "invert" a changeset object. Applying an inverted 756 ** changeset to a database reverses the effects of applying the uninverted 757 ** changeset. Specifically: 758 ** 759 ** <ul> 760 ** <li> Each DELETE change is changed to an INSERT, and 761 ** <li> Each INSERT change is changed to a DELETE, and 762 ** <li> For each UPDATE change, the old.* and new.* values are exchanged. 763 ** </ul> 764 ** 765 ** This function does not change the order in which changes appear within 766 ** the changeset. It merely reverses the sense of each individual change. 767 ** 768 ** If successful, a pointer to a buffer containing the inverted changeset 769 ** is stored in *ppOut, the size of the same buffer is stored in *pnOut, and 770 ** SQLITE_OK is returned. If an error occurs, both *pnOut and *ppOut are 771 ** zeroed and an SQLite error code returned. 772 ** 773 ** It is the responsibility of the caller to eventually call sqlite3_free() 774 ** on the *ppOut pointer to free the buffer allocation following a successful 775 ** call to this function. 776 ** 777 ** WARNING/TODO: This function currently assumes that the input is a valid 778 ** changeset. If it is not, the results are undefined. 779 */ 780 int sqlite3changeset_invert( 781 int nIn, const void *pIn, /* Input changeset */ 782 int *pnOut, void **ppOut /* OUT: Inverse of input */ 783 ); 784 785 /* 786 ** CAPI3REF: Concatenate Two Changeset Objects 787 ** 788 ** This function is used to concatenate two changesets, A and B, into a 789 ** single changeset. The result is a changeset equivalent to applying 790 ** changeset A followed by changeset B. 791 ** 792 ** This function combines the two input changesets using an 793 ** sqlite3_changegroup object. Calling it produces similar results as the 794 ** following code fragment: 795 ** 796 ** <pre> 797 ** sqlite3_changegroup *pGrp; 798 ** rc = sqlite3_changegroup_new(&pGrp); 799 ** if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nA, pA); 800 ** if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nB, pB); 801 ** if( rc==SQLITE_OK ){ 802 ** rc = sqlite3changegroup_output(pGrp, pnOut, ppOut); 803 ** }else{ 804 ** *ppOut = 0; 805 ** *pnOut = 0; 806 ** } 807 ** </pre> 808 ** 809 ** Refer to the sqlite3_changegroup documentation below for details. 810 */ 811 int sqlite3changeset_concat( 812 int nA, /* Number of bytes in buffer pA */ 813 void *pA, /* Pointer to buffer containing changeset A */ 814 int nB, /* Number of bytes in buffer pB */ 815 void *pB, /* Pointer to buffer containing changeset B */ 816 int *pnOut, /* OUT: Number of bytes in output changeset */ 817 void **ppOut /* OUT: Buffer containing output changeset */ 818 ); 819 820 821 /* 822 ** CAPI3REF: Changegroup Handle 823 ** 824 ** A changegroup is an object used to combine two or more 825 ** [changesets] or [patchsets] 826 */ 827 typedef struct sqlite3_changegroup sqlite3_changegroup; 828 829 /* 830 ** CAPI3REF: Create A New Changegroup Object 831 ** CONSTRUCTOR: sqlite3_changegroup 832 ** 833 ** An sqlite3_changegroup object is used to combine two or more changesets 834 ** (or patchsets) into a single changeset (or patchset). A single changegroup 835 ** object may combine changesets or patchsets, but not both. The output is 836 ** always in the same format as the input. 837 ** 838 ** If successful, this function returns SQLITE_OK and populates (*pp) with 839 ** a pointer to a new sqlite3_changegroup object before returning. The caller 840 ** should eventually free the returned object using a call to 841 ** sqlite3changegroup_delete(). If an error occurs, an SQLite error code 842 ** (i.e. SQLITE_NOMEM) is returned and *pp is set to NULL. 843 ** 844 ** The usual usage pattern for an sqlite3_changegroup object is as follows: 845 ** 846 ** <ul> 847 ** <li> It is created using a call to sqlite3changegroup_new(). 848 ** 849 ** <li> Zero or more changesets (or patchsets) are added to the object 850 ** by calling sqlite3changegroup_add(). 851 ** 852 ** <li> The result of combining all input changesets together is obtained 853 ** by the application via a call to sqlite3changegroup_output(). 854 ** 855 ** <li> The object is deleted using a call to sqlite3changegroup_delete(). 856 ** </ul> 857 ** 858 ** Any number of calls to add() and output() may be made between the calls to 859 ** new() and delete(), and in any order. 860 ** 861 ** As well as the regular sqlite3changegroup_add() and 862 ** sqlite3changegroup_output() functions, also available are the streaming 863 ** versions sqlite3changegroup_add_strm() and sqlite3changegroup_output_strm(). 864 */ 865 int sqlite3changegroup_new(sqlite3_changegroup **pp); 866 867 /* 868 ** CAPI3REF: Add A Changeset To A Changegroup 869 ** METHOD: sqlite3_changegroup 870 ** 871 ** Add all changes within the changeset (or patchset) in buffer pData (size 872 ** nData bytes) to the changegroup. 873 ** 874 ** If the buffer contains a patchset, then all prior calls to this function 875 ** on the same changegroup object must also have specified patchsets. Or, if 876 ** the buffer contains a changeset, so must have the earlier calls to this 877 ** function. Otherwise, SQLITE_ERROR is returned and no changes are added 878 ** to the changegroup. 879 ** 880 ** Rows within the changeset and changegroup are identified by the values in 881 ** their PRIMARY KEY columns. A change in the changeset is considered to 882 ** apply to the same row as a change already present in the changegroup if 883 ** the two rows have the same primary key. 884 ** 885 ** Changes to rows that do not already appear in the changegroup are 886 ** simply copied into it. Or, if both the new changeset and the changegroup 887 ** contain changes that apply to a single row, the final contents of the 888 ** changegroup depends on the type of each change, as follows: 889 ** 890 ** <table border=1 style="margin-left:8ex;margin-right:8ex"> 891 ** <tr><th style="white-space:pre">Existing Change </th> 892 ** <th style="white-space:pre">New Change </th> 893 ** <th>Output Change 894 ** <tr><td>INSERT <td>INSERT <td> 895 ** The new change is ignored. This case does not occur if the new 896 ** changeset was recorded immediately after the changesets already 897 ** added to the changegroup. 898 ** <tr><td>INSERT <td>UPDATE <td> 899 ** The INSERT change remains in the changegroup. The values in the 900 ** INSERT change are modified as if the row was inserted by the 901 ** existing change and then updated according to the new change. 902 ** <tr><td>INSERT <td>DELETE <td> 903 ** The existing INSERT is removed from the changegroup. The DELETE is 904 ** not added. 905 ** <tr><td>UPDATE <td>INSERT <td> 906 ** The new change is ignored. This case does not occur if the new 907 ** changeset was recorded immediately after the changesets already 908 ** added to the changegroup. 909 ** <tr><td>UPDATE <td>UPDATE <td> 910 ** The existing UPDATE remains within the changegroup. It is amended 911 ** so that the accompanying values are as if the row was updated once 912 ** by the existing change and then again by the new change. 913 ** <tr><td>UPDATE <td>DELETE <td> 914 ** The existing UPDATE is replaced by the new DELETE within the 915 ** changegroup. 916 ** <tr><td>DELETE <td>INSERT <td> 917 ** If one or more of the column values in the row inserted by the 918 ** new change differ from those in the row deleted by the existing 919 ** change, the existing DELETE is replaced by an UPDATE within the 920 ** changegroup. Otherwise, if the inserted row is exactly the same 921 ** as the deleted row, the existing DELETE is simply discarded. 922 ** <tr><td>DELETE <td>UPDATE <td> 923 ** The new change is ignored. This case does not occur if the new 924 ** changeset was recorded immediately after the changesets already 925 ** added to the changegroup. 926 ** <tr><td>DELETE <td>DELETE <td> 927 ** The new change is ignored. This case does not occur if the new 928 ** changeset was recorded immediately after the changesets already 929 ** added to the changegroup. 930 ** </table> 931 ** 932 ** If the new changeset contains changes to a table that is already present 933 ** in the changegroup, then the number of columns and the position of the 934 ** primary key columns for the table must be consistent. If this is not the 935 ** case, this function fails with SQLITE_SCHEMA. If the input changeset 936 ** appears to be corrupt and the corruption is detected, SQLITE_CORRUPT is 937 ** returned. Or, if an out-of-memory condition occurs during processing, this 938 ** function returns SQLITE_NOMEM. In all cases, if an error occurs the state 939 ** of the final contents of the changegroup is undefined. 940 ** 941 ** If no error occurs, SQLITE_OK is returned. 942 */ 943 int sqlite3changegroup_add(sqlite3_changegroup*, int nData, void *pData); 944 945 /* 946 ** CAPI3REF: Obtain A Composite Changeset From A Changegroup 947 ** METHOD: sqlite3_changegroup 948 ** 949 ** Obtain a buffer containing a changeset (or patchset) representing the 950 ** current contents of the changegroup. If the inputs to the changegroup 951 ** were themselves changesets, the output is a changeset. Or, if the 952 ** inputs were patchsets, the output is also a patchset. 953 ** 954 ** As with the output of the sqlite3session_changeset() and 955 ** sqlite3session_patchset() functions, all changes related to a single 956 ** table are grouped together in the output of this function. Tables appear 957 ** in the same order as for the very first changeset added to the changegroup. 958 ** If the second or subsequent changesets added to the changegroup contain 959 ** changes for tables that do not appear in the first changeset, they are 960 ** appended onto the end of the output changeset, again in the order in 961 ** which they are first encountered. 962 ** 963 ** If an error occurs, an SQLite error code is returned and the output 964 ** variables (*pnData) and (*ppData) are set to 0. Otherwise, SQLITE_OK 965 ** is returned and the output variables are set to the size of and a 966 ** pointer to the output buffer, respectively. In this case it is the 967 ** responsibility of the caller to eventually free the buffer using a 968 ** call to sqlite3_free(). 969 */ 970 int sqlite3changegroup_output( 971 sqlite3_changegroup*, 972 int *pnData, /* OUT: Size of output buffer in bytes */ 973 void **ppData /* OUT: Pointer to output buffer */ 974 ); 975 976 /* 977 ** CAPI3REF: Delete A Changegroup Object 978 ** DESTRUCTOR: sqlite3_changegroup 979 */ 980 void sqlite3changegroup_delete(sqlite3_changegroup*); 981 982 /* 983 ** CAPI3REF: Apply A Changeset To A Database 984 ** 985 ** Apply a changeset or patchset to a database. These functions attempt to 986 ** update the "main" database attached to handle db with the changes found in 987 ** the changeset passed via the second and third arguments. 988 ** 989 ** The fourth argument (xFilter) passed to these functions is the "filter 990 ** callback". If it is not NULL, then for each table affected by at least one 991 ** change in the changeset, the filter callback is invoked with 992 ** the table name as the second argument, and a copy of the context pointer 993 ** passed as the sixth argument as the first. If the "filter callback" 994 ** returns zero, then no attempt is made to apply any changes to the table. 995 ** Otherwise, if the return value is non-zero or the xFilter argument to 996 ** is NULL, all changes related to the table are attempted. 997 ** 998 ** For each table that is not excluded by the filter callback, this function 999 ** tests that the target database contains a compatible table. A table is 1000 ** considered compatible if all of the following are true: 1001 ** 1002 ** <ul> 1003 ** <li> The table has the same name as the name recorded in the 1004 ** changeset, and 1005 ** <li> The table has at least as many columns as recorded in the 1006 ** changeset, and 1007 ** <li> The table has primary key columns in the same position as 1008 ** recorded in the changeset. 1009 ** </ul> 1010 ** 1011 ** If there is no compatible table, it is not an error, but none of the 1012 ** changes associated with the table are applied. A warning message is issued 1013 ** via the sqlite3_log() mechanism with the error code SQLITE_SCHEMA. At most 1014 ** one such warning is issued for each table in the changeset. 1015 ** 1016 ** For each change for which there is a compatible table, an attempt is made 1017 ** to modify the table contents according to the UPDATE, INSERT or DELETE 1018 ** change. If a change cannot be applied cleanly, the conflict handler 1019 ** function passed as the fifth argument to sqlite3changeset_apply() may be 1020 ** invoked. A description of exactly when the conflict handler is invoked for 1021 ** each type of change is below. 1022 ** 1023 ** Unlike the xFilter argument, xConflict may not be passed NULL. The results 1024 ** of passing anything other than a valid function pointer as the xConflict 1025 ** argument are undefined. 1026 ** 1027 ** Each time the conflict handler function is invoked, it must return one 1028 ** of [SQLITE_CHANGESET_OMIT], [SQLITE_CHANGESET_ABORT] or 1029 ** [SQLITE_CHANGESET_REPLACE]. SQLITE_CHANGESET_REPLACE may only be returned 1030 ** if the second argument passed to the conflict handler is either 1031 ** SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If the conflict-handler 1032 ** returns an illegal value, any changes already made are rolled back and 1033 ** the call to sqlite3changeset_apply() returns SQLITE_MISUSE. Different 1034 ** actions are taken by sqlite3changeset_apply() depending on the value 1035 ** returned by each invocation of the conflict-handler function. Refer to 1036 ** the documentation for the three 1037 ** [SQLITE_CHANGESET_OMIT|available return values] for details. 1038 ** 1039 ** <dl> 1040 ** <dt>DELETE Changes<dd> 1041 ** For each DELETE change, the function checks if the target database 1042 ** contains a row with the same primary key value (or values) as the 1043 ** original row values stored in the changeset. If it does, and the values 1044 ** stored in all non-primary key columns also match the values stored in 1045 ** the changeset the row is deleted from the target database. 1046 ** 1047 ** If a row with matching primary key values is found, but one or more of 1048 ** the non-primary key fields contains a value different from the original 1049 ** row value stored in the changeset, the conflict-handler function is 1050 ** invoked with [SQLITE_CHANGESET_DATA] as the second argument. If the 1051 ** database table has more columns than are recorded in the changeset, 1052 ** only the values of those non-primary key fields are compared against 1053 ** the current database contents - any trailing database table columns 1054 ** are ignored. 1055 ** 1056 ** If no row with matching primary key values is found in the database, 1057 ** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND] 1058 ** passed as the second argument. 1059 ** 1060 ** If the DELETE operation is attempted, but SQLite returns SQLITE_CONSTRAINT 1061 ** (which can only happen if a foreign key constraint is violated), the 1062 ** conflict-handler function is invoked with [SQLITE_CHANGESET_CONSTRAINT] 1063 ** passed as the second argument. This includes the case where the DELETE 1064 ** operation is attempted because an earlier call to the conflict handler 1065 ** function returned [SQLITE_CHANGESET_REPLACE]. 1066 ** 1067 ** <dt>INSERT Changes<dd> 1068 ** For each INSERT change, an attempt is made to insert the new row into 1069 ** the database. If the changeset row contains fewer fields than the 1070 ** database table, the trailing fields are populated with their default 1071 ** values. 1072 ** 1073 ** If the attempt to insert the row fails because the database already 1074 ** contains a row with the same primary key values, the conflict handler 1075 ** function is invoked with the second argument set to 1076 ** [SQLITE_CHANGESET_CONFLICT]. 1077 ** 1078 ** If the attempt to insert the row fails because of some other constraint 1079 ** violation (e.g. NOT NULL or UNIQUE), the conflict handler function is 1080 ** invoked with the second argument set to [SQLITE_CHANGESET_CONSTRAINT]. 1081 ** This includes the case where the INSERT operation is re-attempted because 1082 ** an earlier call to the conflict handler function returned 1083 ** [SQLITE_CHANGESET_REPLACE]. 1084 ** 1085 ** <dt>UPDATE Changes<dd> 1086 ** For each UPDATE change, the function checks if the target database 1087 ** contains a row with the same primary key value (or values) as the 1088 ** original row values stored in the changeset. If it does, and the values 1089 ** stored in all modified non-primary key columns also match the values 1090 ** stored in the changeset the row is updated within the target database. 1091 ** 1092 ** If a row with matching primary key values is found, but one or more of 1093 ** the modified non-primary key fields contains a value different from an 1094 ** original row value stored in the changeset, the conflict-handler function 1095 ** is invoked with [SQLITE_CHANGESET_DATA] as the second argument. Since 1096 ** UPDATE changes only contain values for non-primary key fields that are 1097 ** to be modified, only those fields need to match the original values to 1098 ** avoid the SQLITE_CHANGESET_DATA conflict-handler callback. 1099 ** 1100 ** If no row with matching primary key values is found in the database, 1101 ** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND] 1102 ** passed as the second argument. 1103 ** 1104 ** If the UPDATE operation is attempted, but SQLite returns 1105 ** SQLITE_CONSTRAINT, the conflict-handler function is invoked with 1106 ** [SQLITE_CHANGESET_CONSTRAINT] passed as the second argument. 1107 ** This includes the case where the UPDATE operation is attempted after 1108 ** an earlier call to the conflict handler function returned 1109 ** [SQLITE_CHANGESET_REPLACE]. 1110 ** </dl> 1111 ** 1112 ** It is safe to execute SQL statements, including those that write to the 1113 ** table that the callback related to, from within the xConflict callback. 1114 ** This can be used to further customize the application's conflict 1115 ** resolution strategy. 1116 ** 1117 ** All changes made by these functions are enclosed in a savepoint transaction. 1118 ** If any other error (aside from a constraint failure when attempting to 1119 ** write to the target database) occurs, then the savepoint transaction is 1120 ** rolled back, restoring the target database to its original state, and an 1121 ** SQLite error code returned. 1122 ** 1123 ** If the output parameters (ppRebase) and (pnRebase) are non-NULL and 1124 ** the input is a changeset (not a patchset), then sqlite3changeset_apply_v2() 1125 ** may set (*ppRebase) to point to a "rebase" that may be used with the 1126 ** sqlite3_rebaser APIs buffer before returning. In this case (*pnRebase) 1127 ** is set to the size of the buffer in bytes. It is the responsibility of the 1128 ** caller to eventually free any such buffer using sqlite3_free(). The buffer 1129 ** is only allocated and populated if one or more conflicts were encountered 1130 ** while applying the patchset. See comments surrounding the sqlite3_rebaser 1131 ** APIs for further details. 1132 ** 1133 ** The behavior of sqlite3changeset_apply_v2() and its streaming equivalent 1134 ** may be modified by passing a combination of 1135 ** [SQLITE_CHANGESETAPPLY_NOSAVEPOINT | supported flags] as the 9th parameter. 1136 ** 1137 ** Note that the sqlite3changeset_apply_v2() API is still <b>experimental</b> 1138 ** and therefore subject to change. 1139 */ 1140 int sqlite3changeset_apply( 1141 sqlite3 *db, /* Apply change to "main" db of this handle */ 1142 int nChangeset, /* Size of changeset in bytes */ 1143 void *pChangeset, /* Changeset blob */ 1144 int(*xFilter)( 1145 void *pCtx, /* Copy of sixth arg to _apply() */ 1146 const char *zTab /* Table name */ 1147 ), 1148 int(*xConflict)( 1149 void *pCtx, /* Copy of sixth arg to _apply() */ 1150 int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ 1151 sqlite3_changeset_iter *p /* Handle describing change and conflict */ 1152 ), 1153 void *pCtx /* First argument passed to xConflict */ 1154 ); 1155 int sqlite3changeset_apply_v2( 1156 sqlite3 *db, /* Apply change to "main" db of this handle */ 1157 int nChangeset, /* Size of changeset in bytes */ 1158 void *pChangeset, /* Changeset blob */ 1159 int(*xFilter)( 1160 void *pCtx, /* Copy of sixth arg to _apply() */ 1161 const char *zTab /* Table name */ 1162 ), 1163 int(*xConflict)( 1164 void *pCtx, /* Copy of sixth arg to _apply() */ 1165 int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ 1166 sqlite3_changeset_iter *p /* Handle describing change and conflict */ 1167 ), 1168 void *pCtx, /* First argument passed to xConflict */ 1169 void **ppRebase, int *pnRebase, /* OUT: Rebase data */ 1170 int flags /* SESSION_CHANGESETAPPLY_* flags */ 1171 ); 1172 1173 /* 1174 ** CAPI3REF: Flags for sqlite3changeset_apply_v2 1175 ** 1176 ** The following flags may passed via the 9th parameter to 1177 ** [sqlite3changeset_apply_v2] and [sqlite3changeset_apply_v2_strm]: 1178 ** 1179 ** <dl> 1180 ** <dt>SQLITE_CHANGESETAPPLY_NOSAVEPOINT <dd> 1181 ** Usually, the sessions module encloses all operations performed by 1182 ** a single call to apply_v2() or apply_v2_strm() in a [SAVEPOINT]. The 1183 ** SAVEPOINT is committed if the changeset or patchset is successfully 1184 ** applied, or rolled back if an error occurs. Specifying this flag 1185 ** causes the sessions module to omit this savepoint. In this case, if the 1186 ** caller has an open transaction or savepoint when apply_v2() is called, 1187 ** it may revert the partially applied changeset by rolling it back. 1188 ** 1189 ** <dt>SQLITE_CHANGESETAPPLY_INVERT <dd> 1190 ** Invert the changeset before applying it. This is equivalent to inverting 1191 ** a changeset using sqlite3changeset_invert() before applying it. It is 1192 ** an error to specify this flag with a patchset. 1193 */ 1194 #define SQLITE_CHANGESETAPPLY_NOSAVEPOINT 0x0001 1195 #define SQLITE_CHANGESETAPPLY_INVERT 0x0002 1196 1197 /* 1198 ** CAPI3REF: Constants Passed To The Conflict Handler 1199 ** 1200 ** Values that may be passed as the second argument to a conflict-handler. 1201 ** 1202 ** <dl> 1203 ** <dt>SQLITE_CHANGESET_DATA<dd> 1204 ** The conflict handler is invoked with CHANGESET_DATA as the second argument 1205 ** when processing a DELETE or UPDATE change if a row with the required 1206 ** PRIMARY KEY fields is present in the database, but one or more other 1207 ** (non primary-key) fields modified by the update do not contain the 1208 ** expected "before" values. 1209 ** 1210 ** The conflicting row, in this case, is the database row with the matching 1211 ** primary key. 1212 ** 1213 ** <dt>SQLITE_CHANGESET_NOTFOUND<dd> 1214 ** The conflict handler is invoked with CHANGESET_NOTFOUND as the second 1215 ** argument when processing a DELETE or UPDATE change if a row with the 1216 ** required PRIMARY KEY fields is not present in the database. 1217 ** 1218 ** There is no conflicting row in this case. The results of invoking the 1219 ** sqlite3changeset_conflict() API are undefined. 1220 ** 1221 ** <dt>SQLITE_CHANGESET_CONFLICT<dd> 1222 ** CHANGESET_CONFLICT is passed as the second argument to the conflict 1223 ** handler while processing an INSERT change if the operation would result 1224 ** in duplicate primary key values. 1225 ** 1226 ** The conflicting row in this case is the database row with the matching 1227 ** primary key. 1228 ** 1229 ** <dt>SQLITE_CHANGESET_FOREIGN_KEY<dd> 1230 ** If foreign key handling is enabled, and applying a changeset leaves the 1231 ** database in a state containing foreign key violations, the conflict 1232 ** handler is invoked with CHANGESET_FOREIGN_KEY as the second argument 1233 ** exactly once before the changeset is committed. If the conflict handler 1234 ** returns CHANGESET_OMIT, the changes, including those that caused the 1235 ** foreign key constraint violation, are committed. Or, if it returns 1236 ** CHANGESET_ABORT, the changeset is rolled back. 1237 ** 1238 ** No current or conflicting row information is provided. The only function 1239 ** it is possible to call on the supplied sqlite3_changeset_iter handle 1240 ** is sqlite3changeset_fk_conflicts(). 1241 ** 1242 ** <dt>SQLITE_CHANGESET_CONSTRAINT<dd> 1243 ** If any other constraint violation occurs while applying a change (i.e. 1244 ** a UNIQUE, CHECK or NOT NULL constraint), the conflict handler is 1245 ** invoked with CHANGESET_CONSTRAINT as the second argument. 1246 ** 1247 ** There is no conflicting row in this case. The results of invoking the 1248 ** sqlite3changeset_conflict() API are undefined. 1249 ** 1250 ** </dl> 1251 */ 1252 #define SQLITE_CHANGESET_DATA 1 1253 #define SQLITE_CHANGESET_NOTFOUND 2 1254 #define SQLITE_CHANGESET_CONFLICT 3 1255 #define SQLITE_CHANGESET_CONSTRAINT 4 1256 #define SQLITE_CHANGESET_FOREIGN_KEY 5 1257 1258 /* 1259 ** CAPI3REF: Constants Returned By The Conflict Handler 1260 ** 1261 ** A conflict handler callback must return one of the following three values. 1262 ** 1263 ** <dl> 1264 ** <dt>SQLITE_CHANGESET_OMIT<dd> 1265 ** If a conflict handler returns this value no special action is taken. The 1266 ** change that caused the conflict is not applied. The session module 1267 ** continues to the next change in the changeset. 1268 ** 1269 ** <dt>SQLITE_CHANGESET_REPLACE<dd> 1270 ** This value may only be returned if the second argument to the conflict 1271 ** handler was SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If this 1272 ** is not the case, any changes applied so far are rolled back and the 1273 ** call to sqlite3changeset_apply() returns SQLITE_MISUSE. 1274 ** 1275 ** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_DATA conflict 1276 ** handler, then the conflicting row is either updated or deleted, depending 1277 ** on the type of change. 1278 ** 1279 ** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_CONFLICT conflict 1280 ** handler, then the conflicting row is removed from the database and a 1281 ** second attempt to apply the change is made. If this second attempt fails, 1282 ** the original row is restored to the database before continuing. 1283 ** 1284 ** <dt>SQLITE_CHANGESET_ABORT<dd> 1285 ** If this value is returned, any changes applied so far are rolled back 1286 ** and the call to sqlite3changeset_apply() returns SQLITE_ABORT. 1287 ** </dl> 1288 */ 1289 #define SQLITE_CHANGESET_OMIT 0 1290 #define SQLITE_CHANGESET_REPLACE 1 1291 #define SQLITE_CHANGESET_ABORT 2 1292 1293 /* 1294 ** CAPI3REF: Rebasing changesets 1295 ** EXPERIMENTAL 1296 ** 1297 ** Suppose there is a site hosting a database in state S0. And that 1298 ** modifications are made that move that database to state S1 and a 1299 ** changeset recorded (the "local" changeset). Then, a changeset based 1300 ** on S0 is received from another site (the "remote" changeset) and 1301 ** applied to the database. The database is then in state 1302 ** (S1+"remote"), where the exact state depends on any conflict 1303 ** resolution decisions (OMIT or REPLACE) made while applying "remote". 1304 ** Rebasing a changeset is to update it to take those conflict 1305 ** resolution decisions into account, so that the same conflicts 1306 ** do not have to be resolved elsewhere in the network. 1307 ** 1308 ** For example, if both the local and remote changesets contain an 1309 ** INSERT of the same key on "CREATE TABLE t1(a PRIMARY KEY, b)": 1310 ** 1311 ** local: INSERT INTO t1 VALUES(1, 'v1'); 1312 ** remote: INSERT INTO t1 VALUES(1, 'v2'); 1313 ** 1314 ** and the conflict resolution is REPLACE, then the INSERT change is 1315 ** removed from the local changeset (it was overridden). Or, if the 1316 ** conflict resolution was "OMIT", then the local changeset is modified 1317 ** to instead contain: 1318 ** 1319 ** UPDATE t1 SET b = 'v2' WHERE a=1; 1320 ** 1321 ** Changes within the local changeset are rebased as follows: 1322 ** 1323 ** <dl> 1324 ** <dt>Local INSERT<dd> 1325 ** This may only conflict with a remote INSERT. If the conflict 1326 ** resolution was OMIT, then add an UPDATE change to the rebased 1327 ** changeset. Or, if the conflict resolution was REPLACE, add 1328 ** nothing to the rebased changeset. 1329 ** 1330 ** <dt>Local DELETE<dd> 1331 ** This may conflict with a remote UPDATE or DELETE. In both cases the 1332 ** only possible resolution is OMIT. If the remote operation was a 1333 ** DELETE, then add no change to the rebased changeset. If the remote 1334 ** operation was an UPDATE, then the old.* fields of change are updated 1335 ** to reflect the new.* values in the UPDATE. 1336 ** 1337 ** <dt>Local UPDATE<dd> 1338 ** This may conflict with a remote UPDATE or DELETE. If it conflicts 1339 ** with a DELETE, and the conflict resolution was OMIT, then the update 1340 ** is changed into an INSERT. Any undefined values in the new.* record 1341 ** from the update change are filled in using the old.* values from 1342 ** the conflicting DELETE. Or, if the conflict resolution was REPLACE, 1343 ** the UPDATE change is simply omitted from the rebased changeset. 1344 ** 1345 ** If conflict is with a remote UPDATE and the resolution is OMIT, then 1346 ** the old.* values are rebased using the new.* values in the remote 1347 ** change. Or, if the resolution is REPLACE, then the change is copied 1348 ** into the rebased changeset with updates to columns also updated by 1349 ** the conflicting remote UPDATE removed. If this means no columns would 1350 ** be updated, the change is omitted. 1351 ** </dl> 1352 ** 1353 ** A local change may be rebased against multiple remote changes 1354 ** simultaneously. If a single key is modified by multiple remote 1355 ** changesets, they are combined as follows before the local changeset 1356 ** is rebased: 1357 ** 1358 ** <ul> 1359 ** <li> If there has been one or more REPLACE resolutions on a 1360 ** key, it is rebased according to a REPLACE. 1361 ** 1362 ** <li> If there have been no REPLACE resolutions on a key, then 1363 ** the local changeset is rebased according to the most recent 1364 ** of the OMIT resolutions. 1365 ** </ul> 1366 ** 1367 ** Note that conflict resolutions from multiple remote changesets are 1368 ** combined on a per-field basis, not per-row. This means that in the 1369 ** case of multiple remote UPDATE operations, some fields of a single 1370 ** local change may be rebased for REPLACE while others are rebased for 1371 ** OMIT. 1372 ** 1373 ** In order to rebase a local changeset, the remote changeset must first 1374 ** be applied to the local database using sqlite3changeset_apply_v2() and 1375 ** the buffer of rebase information captured. Then: 1376 ** 1377 ** <ol> 1378 ** <li> An sqlite3_rebaser object is created by calling 1379 ** sqlite3rebaser_create(). 1380 ** <li> The new object is configured with the rebase buffer obtained from 1381 ** sqlite3changeset_apply_v2() by calling sqlite3rebaser_configure(). 1382 ** If the local changeset is to be rebased against multiple remote 1383 ** changesets, then sqlite3rebaser_configure() should be called 1384 ** multiple times, in the same order that the multiple 1385 ** sqlite3changeset_apply_v2() calls were made. 1386 ** <li> Each local changeset is rebased by calling sqlite3rebaser_rebase(). 1387 ** <li> The sqlite3_rebaser object is deleted by calling 1388 ** sqlite3rebaser_delete(). 1389 ** </ol> 1390 */ 1391 typedef struct sqlite3_rebaser sqlite3_rebaser; 1392 1393 /* 1394 ** CAPI3REF: Create a changeset rebaser object. 1395 ** EXPERIMENTAL 1396 ** 1397 ** Allocate a new changeset rebaser object. If successful, set (*ppNew) to 1398 ** point to the new object and return SQLITE_OK. Otherwise, if an error 1399 ** occurs, return an SQLite error code (e.g. SQLITE_NOMEM) and set (*ppNew) 1400 ** to NULL. 1401 */ 1402 int sqlite3rebaser_create(sqlite3_rebaser **ppNew); 1403 1404 /* 1405 ** CAPI3REF: Configure a changeset rebaser object. 1406 ** EXPERIMENTAL 1407 ** 1408 ** Configure the changeset rebaser object to rebase changesets according 1409 ** to the conflict resolutions described by buffer pRebase (size nRebase 1410 ** bytes), which must have been obtained from a previous call to 1411 ** sqlite3changeset_apply_v2(). 1412 */ 1413 int sqlite3rebaser_configure( 1414 sqlite3_rebaser*, 1415 int nRebase, const void *pRebase 1416 ); 1417 1418 /* 1419 ** CAPI3REF: Rebase a changeset 1420 ** EXPERIMENTAL 1421 ** 1422 ** Argument pIn must point to a buffer containing a changeset nIn bytes 1423 ** in size. This function allocates and populates a buffer with a copy 1424 ** of the changeset rebased according to the configuration of the 1425 ** rebaser object passed as the first argument. If successful, (*ppOut) 1426 ** is set to point to the new buffer containing the rebased changeset and 1427 ** (*pnOut) to its size in bytes and SQLITE_OK returned. It is the 1428 ** responsibility of the caller to eventually free the new buffer using 1429 ** sqlite3_free(). Otherwise, if an error occurs, (*ppOut) and (*pnOut) 1430 ** are set to zero and an SQLite error code returned. 1431 */ 1432 int sqlite3rebaser_rebase( 1433 sqlite3_rebaser*, 1434 int nIn, const void *pIn, 1435 int *pnOut, void **ppOut 1436 ); 1437 1438 /* 1439 ** CAPI3REF: Delete a changeset rebaser object. 1440 ** EXPERIMENTAL 1441 ** 1442 ** Delete the changeset rebaser object and all associated resources. There 1443 ** should be one call to this function for each successful invocation 1444 ** of sqlite3rebaser_create(). 1445 */ 1446 void sqlite3rebaser_delete(sqlite3_rebaser *p); 1447 1448 /* 1449 ** CAPI3REF: Streaming Versions of API functions. 1450 ** 1451 ** The six streaming API xxx_strm() functions serve similar purposes to the 1452 ** corresponding non-streaming API functions: 1453 ** 1454 ** <table border=1 style="margin-left:8ex;margin-right:8ex"> 1455 ** <tr><th>Streaming function<th>Non-streaming equivalent</th> 1456 ** <tr><td>sqlite3changeset_apply_strm<td>[sqlite3changeset_apply] 1457 ** <tr><td>sqlite3changeset_apply_strm_v2<td>[sqlite3changeset_apply_v2] 1458 ** <tr><td>sqlite3changeset_concat_strm<td>[sqlite3changeset_concat] 1459 ** <tr><td>sqlite3changeset_invert_strm<td>[sqlite3changeset_invert] 1460 ** <tr><td>sqlite3changeset_start_strm<td>[sqlite3changeset_start] 1461 ** <tr><td>sqlite3session_changeset_strm<td>[sqlite3session_changeset] 1462 ** <tr><td>sqlite3session_patchset_strm<td>[sqlite3session_patchset] 1463 ** </table> 1464 ** 1465 ** Non-streaming functions that accept changesets (or patchsets) as input 1466 ** require that the entire changeset be stored in a single buffer in memory. 1467 ** Similarly, those that return a changeset or patchset do so by returning 1468 ** a pointer to a single large buffer allocated using sqlite3_malloc(). 1469 ** Normally this is convenient. However, if an application running in a 1470 ** low-memory environment is required to handle very large changesets, the 1471 ** large contiguous memory allocations required can become onerous. 1472 ** 1473 ** In order to avoid this problem, instead of a single large buffer, input 1474 ** is passed to a streaming API functions by way of a callback function that 1475 ** the sessions module invokes to incrementally request input data as it is 1476 ** required. In all cases, a pair of API function parameters such as 1477 ** 1478 ** <pre> 1479 ** int nChangeset, 1480 ** void *pChangeset, 1481 ** </pre> 1482 ** 1483 ** Is replaced by: 1484 ** 1485 ** <pre> 1486 ** int (*xInput)(void *pIn, void *pData, int *pnData), 1487 ** void *pIn, 1488 ** </pre> 1489 ** 1490 ** Each time the xInput callback is invoked by the sessions module, the first 1491 ** argument passed is a copy of the supplied pIn context pointer. The second 1492 ** argument, pData, points to a buffer (*pnData) bytes in size. Assuming no 1493 ** error occurs the xInput method should copy up to (*pnData) bytes of data 1494 ** into the buffer and set (*pnData) to the actual number of bytes copied 1495 ** before returning SQLITE_OK. If the input is completely exhausted, (*pnData) 1496 ** should be set to zero to indicate this. Or, if an error occurs, an SQLite 1497 ** error code should be returned. In all cases, if an xInput callback returns 1498 ** an error, all processing is abandoned and the streaming API function 1499 ** returns a copy of the error code to the caller. 1500 ** 1501 ** In the case of sqlite3changeset_start_strm(), the xInput callback may be 1502 ** invoked by the sessions module at any point during the lifetime of the 1503 ** iterator. If such an xInput callback returns an error, the iterator enters 1504 ** an error state, whereby all subsequent calls to iterator functions 1505 ** immediately fail with the same error code as returned by xInput. 1506 ** 1507 ** Similarly, streaming API functions that return changesets (or patchsets) 1508 ** return them in chunks by way of a callback function instead of via a 1509 ** pointer to a single large buffer. In this case, a pair of parameters such 1510 ** as: 1511 ** 1512 ** <pre> 1513 ** int *pnChangeset, 1514 ** void **ppChangeset, 1515 ** </pre> 1516 ** 1517 ** Is replaced by: 1518 ** 1519 ** <pre> 1520 ** int (*xOutput)(void *pOut, const void *pData, int nData), 1521 ** void *pOut 1522 ** </pre> 1523 ** 1524 ** The xOutput callback is invoked zero or more times to return data to 1525 ** the application. The first parameter passed to each call is a copy of the 1526 ** pOut pointer supplied by the application. The second parameter, pData, 1527 ** points to a buffer nData bytes in size containing the chunk of output 1528 ** data being returned. If the xOutput callback successfully processes the 1529 ** supplied data, it should return SQLITE_OK to indicate success. Otherwise, 1530 ** it should return some other SQLite error code. In this case processing 1531 ** is immediately abandoned and the streaming API function returns a copy 1532 ** of the xOutput error code to the application. 1533 ** 1534 ** The sessions module never invokes an xOutput callback with the third 1535 ** parameter set to a value less than or equal to zero. Other than this, 1536 ** no guarantees are made as to the size of the chunks of data returned. 1537 */ 1538 int sqlite3changeset_apply_strm( 1539 sqlite3 *db, /* Apply change to "main" db of this handle */ 1540 int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */ 1541 void *pIn, /* First arg for xInput */ 1542 int(*xFilter)( 1543 void *pCtx, /* Copy of sixth arg to _apply() */ 1544 const char *zTab /* Table name */ 1545 ), 1546 int(*xConflict)( 1547 void *pCtx, /* Copy of sixth arg to _apply() */ 1548 int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ 1549 sqlite3_changeset_iter *p /* Handle describing change and conflict */ 1550 ), 1551 void *pCtx /* First argument passed to xConflict */ 1552 ); 1553 int sqlite3changeset_apply_v2_strm( 1554 sqlite3 *db, /* Apply change to "main" db of this handle */ 1555 int (*xInput)(void *pIn, void *pData, int *pnData), /* Input function */ 1556 void *pIn, /* First arg for xInput */ 1557 int(*xFilter)( 1558 void *pCtx, /* Copy of sixth arg to _apply() */ 1559 const char *zTab /* Table name */ 1560 ), 1561 int(*xConflict)( 1562 void *pCtx, /* Copy of sixth arg to _apply() */ 1563 int eConflict, /* DATA, MISSING, CONFLICT, CONSTRAINT */ 1564 sqlite3_changeset_iter *p /* Handle describing change and conflict */ 1565 ), 1566 void *pCtx, /* First argument passed to xConflict */ 1567 void **ppRebase, int *pnRebase, 1568 int flags 1569 ); 1570 int sqlite3changeset_concat_strm( 1571 int (*xInputA)(void *pIn, void *pData, int *pnData), 1572 void *pInA, 1573 int (*xInputB)(void *pIn, void *pData, int *pnData), 1574 void *pInB, 1575 int (*xOutput)(void *pOut, const void *pData, int nData), 1576 void *pOut 1577 ); 1578 int sqlite3changeset_invert_strm( 1579 int (*xInput)(void *pIn, void *pData, int *pnData), 1580 void *pIn, 1581 int (*xOutput)(void *pOut, const void *pData, int nData), 1582 void *pOut 1583 ); 1584 int sqlite3changeset_start_strm( 1585 sqlite3_changeset_iter **pp, 1586 int (*xInput)(void *pIn, void *pData, int *pnData), 1587 void *pIn 1588 ); 1589 int sqlite3changeset_start_v2_strm( 1590 sqlite3_changeset_iter **pp, 1591 int (*xInput)(void *pIn, void *pData, int *pnData), 1592 void *pIn, 1593 int flags 1594 ); 1595 int sqlite3session_changeset_strm( 1596 sqlite3_session *pSession, 1597 int (*xOutput)(void *pOut, const void *pData, int nData), 1598 void *pOut 1599 ); 1600 int sqlite3session_patchset_strm( 1601 sqlite3_session *pSession, 1602 int (*xOutput)(void *pOut, const void *pData, int nData), 1603 void *pOut 1604 ); 1605 int sqlite3changegroup_add_strm(sqlite3_changegroup*, 1606 int (*xInput)(void *pIn, void *pData, int *pnData), 1607 void *pIn 1608 ); 1609 int sqlite3changegroup_output_strm(sqlite3_changegroup*, 1610 int (*xOutput)(void *pOut, const void *pData, int nData), 1611 void *pOut 1612 ); 1613 int sqlite3rebaser_rebase_strm( 1614 sqlite3_rebaser *pRebaser, 1615 int (*xInput)(void *pIn, void *pData, int *pnData), 1616 void *pIn, 1617 int (*xOutput)(void *pOut, const void *pData, int nData), 1618 void *pOut 1619 ); 1620 1621 /* 1622 ** CAPI3REF: Configure global parameters 1623 ** 1624 ** The sqlite3session_config() interface is used to make global configuration 1625 ** changes to the sessions module in order to tune it to the specific needs 1626 ** of the application. 1627 ** 1628 ** The sqlite3session_config() interface is not threadsafe. If it is invoked 1629 ** while any other thread is inside any other sessions method then the 1630 ** results are undefined. Furthermore, if it is invoked after any sessions 1631 ** related objects have been created, the results are also undefined. 1632 ** 1633 ** The first argument to the sqlite3session_config() function must be one 1634 ** of the SQLITE_SESSION_CONFIG_XXX constants defined below. The 1635 ** interpretation of the (void*) value passed as the second parameter and 1636 ** the effect of calling this function depends on the value of the first 1637 ** parameter. 1638 ** 1639 ** <dl> 1640 ** <dt>SQLITE_SESSION_CONFIG_STRMSIZE<dd> 1641 ** By default, the sessions module streaming interfaces attempt to input 1642 ** and output data in approximately 1 KiB chunks. This operand may be used 1643 ** to set and query the value of this configuration setting. The pointer 1644 ** passed as the second argument must point to a value of type (int). 1645 ** If this value is greater than 0, it is used as the new streaming data 1646 ** chunk size for both input and output. Before returning, the (int) value 1647 ** pointed to by pArg is set to the final value of the streaming interface 1648 ** chunk size. 1649 ** </dl> 1650 ** 1651 ** This function returns SQLITE_OK if successful, or an SQLite error code 1652 ** otherwise. 1653 */ 1654 int sqlite3session_config(int op, void *pArg); 1655 1656 /* 1657 ** CAPI3REF: Values for sqlite3session_config(). 1658 */ 1659 #define SQLITE_SESSION_CONFIG_STRMSIZE 1 1660 1661 /* 1662 ** Make sure we can call this stuff from C++. 1663 */ 1664 #ifdef __cplusplus 1665 } 1666 #endif 1667 1668 #endif /* !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) */ 1669