1 /* 2 ** 2001 September 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 file contains C code routines that are called by the parser 13 ** to handle INSERT statements in SQLite. 14 */ 15 #include "sqliteInt.h" 16 17 /* 18 ** Generate code that will 19 ** 20 ** (1) acquire a lock for table pTab then 21 ** (2) open pTab as cursor iCur. 22 ** 23 ** If pTab is a WITHOUT ROWID table, then it is the PRIMARY KEY index 24 ** for that table that is actually opened. 25 */ 26 void sqlite3OpenTable( 27 Parse *pParse, /* Generate code into this VDBE */ 28 int iCur, /* The cursor number of the table */ 29 int iDb, /* The database index in sqlite3.aDb[] */ 30 Table *pTab, /* The table to be opened */ 31 int opcode /* OP_OpenRead or OP_OpenWrite */ 32 ){ 33 Vdbe *v; 34 assert( !IsVirtual(pTab) ); 35 v = sqlite3GetVdbe(pParse); 36 assert( opcode==OP_OpenWrite || opcode==OP_OpenRead ); 37 sqlite3TableLock(pParse, iDb, pTab->tnum, 38 (opcode==OP_OpenWrite)?1:0, pTab->zName); 39 if( HasRowid(pTab) ){ 40 sqlite3VdbeAddOp4Int(v, opcode, iCur, pTab->tnum, iDb, pTab->nCol); 41 VdbeComment((v, "%s", pTab->zName)); 42 }else{ 43 Index *pPk = sqlite3PrimaryKeyIndex(pTab); 44 assert( pPk!=0 ); 45 assert( pPk->tnum==pTab->tnum ); 46 sqlite3VdbeAddOp3(v, opcode, iCur, pPk->tnum, iDb); 47 sqlite3VdbeSetP4KeyInfo(pParse, pPk); 48 VdbeComment((v, "%s", pTab->zName)); 49 } 50 } 51 52 /* 53 ** Return a pointer to the column affinity string associated with index 54 ** pIdx. A column affinity string has one character for each column in 55 ** the table, according to the affinity of the column: 56 ** 57 ** Character Column affinity 58 ** ------------------------------ 59 ** 'A' BLOB 60 ** 'B' TEXT 61 ** 'C' NUMERIC 62 ** 'D' INTEGER 63 ** 'F' REAL 64 ** 65 ** An extra 'D' is appended to the end of the string to cover the 66 ** rowid that appears as the last column in every index. 67 ** 68 ** Memory for the buffer containing the column index affinity string 69 ** is managed along with the rest of the Index structure. It will be 70 ** released when sqlite3DeleteIndex() is called. 71 */ 72 const char *sqlite3IndexAffinityStr(sqlite3 *db, Index *pIdx){ 73 if( !pIdx->zColAff ){ 74 /* The first time a column affinity string for a particular index is 75 ** required, it is allocated and populated here. It is then stored as 76 ** a member of the Index structure for subsequent use. 77 ** 78 ** The column affinity string will eventually be deleted by 79 ** sqliteDeleteIndex() when the Index structure itself is cleaned 80 ** up. 81 */ 82 int n; 83 Table *pTab = pIdx->pTable; 84 pIdx->zColAff = (char *)sqlite3DbMallocRaw(0, pIdx->nColumn+1); 85 if( !pIdx->zColAff ){ 86 sqlite3OomFault(db); 87 return 0; 88 } 89 for(n=0; n<pIdx->nColumn; n++){ 90 i16 x = pIdx->aiColumn[n]; 91 if( x>=0 ){ 92 pIdx->zColAff[n] = pTab->aCol[x].affinity; 93 }else if( x==XN_ROWID ){ 94 pIdx->zColAff[n] = SQLITE_AFF_INTEGER; 95 }else{ 96 char aff; 97 assert( x==XN_EXPR ); 98 assert( pIdx->aColExpr!=0 ); 99 aff = sqlite3ExprAffinity(pIdx->aColExpr->a[n].pExpr); 100 if( aff==0 ) aff = SQLITE_AFF_BLOB; 101 pIdx->zColAff[n] = aff; 102 } 103 } 104 pIdx->zColAff[n] = 0; 105 } 106 107 return pIdx->zColAff; 108 } 109 110 /* 111 ** Compute the affinity string for table pTab, if it has not already been 112 ** computed. As an optimization, omit trailing SQLITE_AFF_BLOB affinities. 113 ** 114 ** If the affinity exists (if it is no entirely SQLITE_AFF_BLOB values) and 115 ** if iReg>0 then code an OP_Affinity opcode that will set the affinities 116 ** for register iReg and following. Or if affinities exists and iReg==0, 117 ** then just set the P4 operand of the previous opcode (which should be 118 ** an OP_MakeRecord) to the affinity string. 119 ** 120 ** A column affinity string has one character per column: 121 ** 122 ** Character Column affinity 123 ** ------------------------------ 124 ** 'A' BLOB 125 ** 'B' TEXT 126 ** 'C' NUMERIC 127 ** 'D' INTEGER 128 ** 'E' REAL 129 */ 130 void sqlite3TableAffinity(Vdbe *v, Table *pTab, int iReg){ 131 int i; 132 char *zColAff = pTab->zColAff; 133 if( zColAff==0 ){ 134 sqlite3 *db = sqlite3VdbeDb(v); 135 zColAff = (char *)sqlite3DbMallocRaw(0, pTab->nCol+1); 136 if( !zColAff ){ 137 sqlite3OomFault(db); 138 return; 139 } 140 141 for(i=0; i<pTab->nCol; i++){ 142 zColAff[i] = pTab->aCol[i].affinity; 143 } 144 do{ 145 zColAff[i--] = 0; 146 }while( i>=0 && zColAff[i]==SQLITE_AFF_BLOB ); 147 pTab->zColAff = zColAff; 148 } 149 i = sqlite3Strlen30(zColAff); 150 if( i ){ 151 if( iReg ){ 152 sqlite3VdbeAddOp4(v, OP_Affinity, iReg, i, 0, zColAff, i); 153 }else{ 154 sqlite3VdbeChangeP4(v, -1, zColAff, i); 155 } 156 } 157 } 158 159 /* 160 ** Return non-zero if the table pTab in database iDb or any of its indices 161 ** have been opened at any point in the VDBE program. This is used to see if 162 ** a statement of the form "INSERT INTO <iDb, pTab> SELECT ..." can 163 ** run without using a temporary table for the results of the SELECT. 164 */ 165 static int readsTable(Parse *p, int iDb, Table *pTab){ 166 Vdbe *v = sqlite3GetVdbe(p); 167 int i; 168 int iEnd = sqlite3VdbeCurrentAddr(v); 169 #ifndef SQLITE_OMIT_VIRTUALTABLE 170 VTable *pVTab = IsVirtual(pTab) ? sqlite3GetVTable(p->db, pTab) : 0; 171 #endif 172 173 for(i=1; i<iEnd; i++){ 174 VdbeOp *pOp = sqlite3VdbeGetOp(v, i); 175 assert( pOp!=0 ); 176 if( pOp->opcode==OP_OpenRead && pOp->p3==iDb ){ 177 Index *pIndex; 178 int tnum = pOp->p2; 179 if( tnum==pTab->tnum ){ 180 return 1; 181 } 182 for(pIndex=pTab->pIndex; pIndex; pIndex=pIndex->pNext){ 183 if( tnum==pIndex->tnum ){ 184 return 1; 185 } 186 } 187 } 188 #ifndef SQLITE_OMIT_VIRTUALTABLE 189 if( pOp->opcode==OP_VOpen && pOp->p4.pVtab==pVTab ){ 190 assert( pOp->p4.pVtab!=0 ); 191 assert( pOp->p4type==P4_VTAB ); 192 return 1; 193 } 194 #endif 195 } 196 return 0; 197 } 198 199 #ifndef SQLITE_OMIT_AUTOINCREMENT 200 /* 201 ** Locate or create an AutoincInfo structure associated with table pTab 202 ** which is in database iDb. Return the register number for the register 203 ** that holds the maximum rowid. Return zero if pTab is not an AUTOINCREMENT 204 ** table. (Also return zero when doing a VACUUM since we do not want to 205 ** update the AUTOINCREMENT counters during a VACUUM.) 206 ** 207 ** There is at most one AutoincInfo structure per table even if the 208 ** same table is autoincremented multiple times due to inserts within 209 ** triggers. A new AutoincInfo structure is created if this is the 210 ** first use of table pTab. On 2nd and subsequent uses, the original 211 ** AutoincInfo structure is used. 212 ** 213 ** Three memory locations are allocated: 214 ** 215 ** (1) Register to hold the name of the pTab table. 216 ** (2) Register to hold the maximum ROWID of pTab. 217 ** (3) Register to hold the rowid in sqlite_sequence of pTab 218 ** 219 ** The 2nd register is the one that is returned. That is all the 220 ** insert routine needs to know about. 221 */ 222 static int autoIncBegin( 223 Parse *pParse, /* Parsing context */ 224 int iDb, /* Index of the database holding pTab */ 225 Table *pTab /* The table we are writing to */ 226 ){ 227 int memId = 0; /* Register holding maximum rowid */ 228 if( (pTab->tabFlags & TF_Autoincrement)!=0 229 && (pParse->db->mDbFlags & DBFLAG_Vacuum)==0 230 ){ 231 Parse *pToplevel = sqlite3ParseToplevel(pParse); 232 AutoincInfo *pInfo; 233 234 pInfo = pToplevel->pAinc; 235 while( pInfo && pInfo->pTab!=pTab ){ pInfo = pInfo->pNext; } 236 if( pInfo==0 ){ 237 pInfo = sqlite3DbMallocRawNN(pParse->db, sizeof(*pInfo)); 238 if( pInfo==0 ) return 0; 239 pInfo->pNext = pToplevel->pAinc; 240 pToplevel->pAinc = pInfo; 241 pInfo->pTab = pTab; 242 pInfo->iDb = iDb; 243 pToplevel->nMem++; /* Register to hold name of table */ 244 pInfo->regCtr = ++pToplevel->nMem; /* Max rowid register */ 245 pToplevel->nMem++; /* Rowid in sqlite_sequence */ 246 } 247 memId = pInfo->regCtr; 248 } 249 return memId; 250 } 251 252 /* 253 ** This routine generates code that will initialize all of the 254 ** register used by the autoincrement tracker. 255 */ 256 void sqlite3AutoincrementBegin(Parse *pParse){ 257 AutoincInfo *p; /* Information about an AUTOINCREMENT */ 258 sqlite3 *db = pParse->db; /* The database connection */ 259 Db *pDb; /* Database only autoinc table */ 260 int memId; /* Register holding max rowid */ 261 Vdbe *v = pParse->pVdbe; /* VDBE under construction */ 262 263 /* This routine is never called during trigger-generation. It is 264 ** only called from the top-level */ 265 assert( pParse->pTriggerTab==0 ); 266 assert( sqlite3IsToplevel(pParse) ); 267 268 assert( v ); /* We failed long ago if this is not so */ 269 for(p = pParse->pAinc; p; p = p->pNext){ 270 static const int iLn = VDBE_OFFSET_LINENO(2); 271 static const VdbeOpList autoInc[] = { 272 /* 0 */ {OP_Null, 0, 0, 0}, 273 /* 1 */ {OP_Rewind, 0, 9, 0}, 274 /* 2 */ {OP_Column, 0, 0, 0}, 275 /* 3 */ {OP_Ne, 0, 7, 0}, 276 /* 4 */ {OP_Rowid, 0, 0, 0}, 277 /* 5 */ {OP_Column, 0, 1, 0}, 278 /* 6 */ {OP_Goto, 0, 9, 0}, 279 /* 7 */ {OP_Next, 0, 2, 0}, 280 /* 8 */ {OP_Integer, 0, 0, 0}, 281 /* 9 */ {OP_Close, 0, 0, 0} 282 }; 283 VdbeOp *aOp; 284 pDb = &db->aDb[p->iDb]; 285 memId = p->regCtr; 286 assert( sqlite3SchemaMutexHeld(db, 0, pDb->pSchema) ); 287 sqlite3OpenTable(pParse, 0, p->iDb, pDb->pSchema->pSeqTab, OP_OpenRead); 288 sqlite3VdbeLoadString(v, memId-1, p->pTab->zName); 289 aOp = sqlite3VdbeAddOpList(v, ArraySize(autoInc), autoInc, iLn); 290 if( aOp==0 ) break; 291 aOp[0].p2 = memId; 292 aOp[0].p3 = memId+1; 293 aOp[2].p3 = memId; 294 aOp[3].p1 = memId-1; 295 aOp[3].p3 = memId; 296 aOp[3].p5 = SQLITE_JUMPIFNULL; 297 aOp[4].p2 = memId+1; 298 aOp[5].p3 = memId; 299 aOp[8].p2 = memId; 300 } 301 } 302 303 /* 304 ** Update the maximum rowid for an autoincrement calculation. 305 ** 306 ** This routine should be called when the regRowid register holds a 307 ** new rowid that is about to be inserted. If that new rowid is 308 ** larger than the maximum rowid in the memId memory cell, then the 309 ** memory cell is updated. 310 */ 311 static void autoIncStep(Parse *pParse, int memId, int regRowid){ 312 if( memId>0 ){ 313 sqlite3VdbeAddOp2(pParse->pVdbe, OP_MemMax, memId, regRowid); 314 } 315 } 316 317 /* 318 ** This routine generates the code needed to write autoincrement 319 ** maximum rowid values back into the sqlite_sequence register. 320 ** Every statement that might do an INSERT into an autoincrement 321 ** table (either directly or through triggers) needs to call this 322 ** routine just before the "exit" code. 323 */ 324 static SQLITE_NOINLINE void autoIncrementEnd(Parse *pParse){ 325 AutoincInfo *p; 326 Vdbe *v = pParse->pVdbe; 327 sqlite3 *db = pParse->db; 328 329 assert( v ); 330 for(p = pParse->pAinc; p; p = p->pNext){ 331 static const int iLn = VDBE_OFFSET_LINENO(2); 332 static const VdbeOpList autoIncEnd[] = { 333 /* 0 */ {OP_NotNull, 0, 2, 0}, 334 /* 1 */ {OP_NewRowid, 0, 0, 0}, 335 /* 2 */ {OP_MakeRecord, 0, 2, 0}, 336 /* 3 */ {OP_Insert, 0, 0, 0}, 337 /* 4 */ {OP_Close, 0, 0, 0} 338 }; 339 VdbeOp *aOp; 340 Db *pDb = &db->aDb[p->iDb]; 341 int iRec; 342 int memId = p->regCtr; 343 344 iRec = sqlite3GetTempReg(pParse); 345 assert( sqlite3SchemaMutexHeld(db, 0, pDb->pSchema) ); 346 sqlite3OpenTable(pParse, 0, p->iDb, pDb->pSchema->pSeqTab, OP_OpenWrite); 347 aOp = sqlite3VdbeAddOpList(v, ArraySize(autoIncEnd), autoIncEnd, iLn); 348 if( aOp==0 ) break; 349 aOp[0].p1 = memId+1; 350 aOp[1].p2 = memId+1; 351 aOp[2].p1 = memId-1; 352 aOp[2].p3 = iRec; 353 aOp[3].p2 = iRec; 354 aOp[3].p3 = memId+1; 355 aOp[3].p5 = OPFLAG_APPEND; 356 sqlite3ReleaseTempReg(pParse, iRec); 357 } 358 } 359 void sqlite3AutoincrementEnd(Parse *pParse){ 360 if( pParse->pAinc ) autoIncrementEnd(pParse); 361 } 362 #else 363 /* 364 ** If SQLITE_OMIT_AUTOINCREMENT is defined, then the three routines 365 ** above are all no-ops 366 */ 367 # define autoIncBegin(A,B,C) (0) 368 # define autoIncStep(A,B,C) 369 #endif /* SQLITE_OMIT_AUTOINCREMENT */ 370 371 372 /* Forward declaration */ 373 static int xferOptimization( 374 Parse *pParse, /* Parser context */ 375 Table *pDest, /* The table we are inserting into */ 376 Select *pSelect, /* A SELECT statement to use as the data source */ 377 int onError, /* How to handle constraint errors */ 378 int iDbDest /* The database of pDest */ 379 ); 380 381 /* 382 ** This routine is called to handle SQL of the following forms: 383 ** 384 ** insert into TABLE (IDLIST) values(EXPRLIST),(EXPRLIST),... 385 ** insert into TABLE (IDLIST) select 386 ** insert into TABLE (IDLIST) default values 387 ** 388 ** The IDLIST following the table name is always optional. If omitted, 389 ** then a list of all (non-hidden) columns for the table is substituted. 390 ** The IDLIST appears in the pColumn parameter. pColumn is NULL if IDLIST 391 ** is omitted. 392 ** 393 ** For the pSelect parameter holds the values to be inserted for the 394 ** first two forms shown above. A VALUES clause is really just short-hand 395 ** for a SELECT statement that omits the FROM clause and everything else 396 ** that follows. If the pSelect parameter is NULL, that means that the 397 ** DEFAULT VALUES form of the INSERT statement is intended. 398 ** 399 ** The code generated follows one of four templates. For a simple 400 ** insert with data coming from a single-row VALUES clause, the code executes 401 ** once straight down through. Pseudo-code follows (we call this 402 ** the "1st template"): 403 ** 404 ** open write cursor to <table> and its indices 405 ** put VALUES clause expressions into registers 406 ** write the resulting record into <table> 407 ** cleanup 408 ** 409 ** The three remaining templates assume the statement is of the form 410 ** 411 ** INSERT INTO <table> SELECT ... 412 ** 413 ** If the SELECT clause is of the restricted form "SELECT * FROM <table2>" - 414 ** in other words if the SELECT pulls all columns from a single table 415 ** and there is no WHERE or LIMIT or GROUP BY or ORDER BY clauses, and 416 ** if <table2> and <table1> are distinct tables but have identical 417 ** schemas, including all the same indices, then a special optimization 418 ** is invoked that copies raw records from <table2> over to <table1>. 419 ** See the xferOptimization() function for the implementation of this 420 ** template. This is the 2nd template. 421 ** 422 ** open a write cursor to <table> 423 ** open read cursor on <table2> 424 ** transfer all records in <table2> over to <table> 425 ** close cursors 426 ** foreach index on <table> 427 ** open a write cursor on the <table> index 428 ** open a read cursor on the corresponding <table2> index 429 ** transfer all records from the read to the write cursors 430 ** close cursors 431 ** end foreach 432 ** 433 ** The 3rd template is for when the second template does not apply 434 ** and the SELECT clause does not read from <table> at any time. 435 ** The generated code follows this template: 436 ** 437 ** X <- A 438 ** goto B 439 ** A: setup for the SELECT 440 ** loop over the rows in the SELECT 441 ** load values into registers R..R+n 442 ** yield X 443 ** end loop 444 ** cleanup after the SELECT 445 ** end-coroutine X 446 ** B: open write cursor to <table> and its indices 447 ** C: yield X, at EOF goto D 448 ** insert the select result into <table> from R..R+n 449 ** goto C 450 ** D: cleanup 451 ** 452 ** The 4th template is used if the insert statement takes its 453 ** values from a SELECT but the data is being inserted into a table 454 ** that is also read as part of the SELECT. In the third form, 455 ** we have to use an intermediate table to store the results of 456 ** the select. The template is like this: 457 ** 458 ** X <- A 459 ** goto B 460 ** A: setup for the SELECT 461 ** loop over the tables in the SELECT 462 ** load value into register R..R+n 463 ** yield X 464 ** end loop 465 ** cleanup after the SELECT 466 ** end co-routine R 467 ** B: open temp table 468 ** L: yield X, at EOF goto M 469 ** insert row from R..R+n into temp table 470 ** goto L 471 ** M: open write cursor to <table> and its indices 472 ** rewind temp table 473 ** C: loop over rows of intermediate table 474 ** transfer values form intermediate table into <table> 475 ** end loop 476 ** D: cleanup 477 */ 478 void sqlite3Insert( 479 Parse *pParse, /* Parser context */ 480 SrcList *pTabList, /* Name of table into which we are inserting */ 481 Select *pSelect, /* A SELECT statement to use as the data source */ 482 IdList *pColumn, /* Column names corresponding to IDLIST. */ 483 int onError /* How to handle constraint errors */ 484 ){ 485 sqlite3 *db; /* The main database structure */ 486 Table *pTab; /* The table to insert into. aka TABLE */ 487 char *zTab; /* Name of the table into which we are inserting */ 488 int i, j; /* Loop counters */ 489 Vdbe *v; /* Generate code into this virtual machine */ 490 Index *pIdx; /* For looping over indices of the table */ 491 int nColumn; /* Number of columns in the data */ 492 int nHidden = 0; /* Number of hidden columns if TABLE is virtual */ 493 int iDataCur = 0; /* VDBE cursor that is the main data repository */ 494 int iIdxCur = 0; /* First index cursor */ 495 int ipkColumn = -1; /* Column that is the INTEGER PRIMARY KEY */ 496 int endOfLoop; /* Label for the end of the insertion loop */ 497 int srcTab = 0; /* Data comes from this temporary cursor if >=0 */ 498 int addrInsTop = 0; /* Jump to label "D" */ 499 int addrCont = 0; /* Top of insert loop. Label "C" in templates 3 and 4 */ 500 SelectDest dest; /* Destination for SELECT on rhs of INSERT */ 501 int iDb; /* Index of database holding TABLE */ 502 u8 useTempTable = 0; /* Store SELECT results in intermediate table */ 503 u8 appendFlag = 0; /* True if the insert is likely to be an append */ 504 u8 withoutRowid; /* 0 for normal table. 1 for WITHOUT ROWID table */ 505 u8 bIdListInOrder; /* True if IDLIST is in table order */ 506 ExprList *pList = 0; /* List of VALUES() to be inserted */ 507 508 /* Register allocations */ 509 int regFromSelect = 0;/* Base register for data coming from SELECT */ 510 int regAutoinc = 0; /* Register holding the AUTOINCREMENT counter */ 511 int regRowCount = 0; /* Memory cell used for the row counter */ 512 int regIns; /* Block of regs holding rowid+data being inserted */ 513 int regRowid; /* registers holding insert rowid */ 514 int regData; /* register holding first column to insert */ 515 int *aRegIdx = 0; /* One register allocated to each index */ 516 517 #ifndef SQLITE_OMIT_TRIGGER 518 int isView; /* True if attempting to insert into a view */ 519 Trigger *pTrigger; /* List of triggers on pTab, if required */ 520 int tmask; /* Mask of trigger times */ 521 #endif 522 523 db = pParse->db; 524 if( pParse->nErr || db->mallocFailed ){ 525 goto insert_cleanup; 526 } 527 dest.iSDParm = 0; /* Suppress a harmless compiler warning */ 528 529 /* If the Select object is really just a simple VALUES() list with a 530 ** single row (the common case) then keep that one row of values 531 ** and discard the other (unused) parts of the pSelect object 532 */ 533 if( pSelect && (pSelect->selFlags & SF_Values)!=0 && pSelect->pPrior==0 ){ 534 pList = pSelect->pEList; 535 pSelect->pEList = 0; 536 sqlite3SelectDelete(db, pSelect); 537 pSelect = 0; 538 } 539 540 /* Locate the table into which we will be inserting new information. 541 */ 542 assert( pTabList->nSrc==1 ); 543 zTab = pTabList->a[0].zName; 544 if( NEVER(zTab==0) ) goto insert_cleanup; 545 pTab = sqlite3SrcListLookup(pParse, pTabList); 546 if( pTab==0 ){ 547 goto insert_cleanup; 548 } 549 iDb = sqlite3SchemaToIndex(db, pTab->pSchema); 550 assert( iDb<db->nDb ); 551 if( sqlite3AuthCheck(pParse, SQLITE_INSERT, pTab->zName, 0, 552 db->aDb[iDb].zDbSName) ){ 553 goto insert_cleanup; 554 } 555 withoutRowid = !HasRowid(pTab); 556 557 /* Figure out if we have any triggers and if the table being 558 ** inserted into is a view 559 */ 560 #ifndef SQLITE_OMIT_TRIGGER 561 pTrigger = sqlite3TriggersExist(pParse, pTab, TK_INSERT, 0, &tmask); 562 isView = pTab->pSelect!=0; 563 #else 564 # define pTrigger 0 565 # define tmask 0 566 # define isView 0 567 #endif 568 #ifdef SQLITE_OMIT_VIEW 569 # undef isView 570 # define isView 0 571 #endif 572 assert( (pTrigger && tmask) || (pTrigger==0 && tmask==0) ); 573 574 /* If pTab is really a view, make sure it has been initialized. 575 ** ViewGetColumnNames() is a no-op if pTab is not a view. 576 */ 577 if( sqlite3ViewGetColumnNames(pParse, pTab) ){ 578 goto insert_cleanup; 579 } 580 581 /* Cannot insert into a read-only table. 582 */ 583 if( sqlite3IsReadOnly(pParse, pTab, tmask) ){ 584 goto insert_cleanup; 585 } 586 587 /* Allocate a VDBE 588 */ 589 v = sqlite3GetVdbe(pParse); 590 if( v==0 ) goto insert_cleanup; 591 if( pParse->nested==0 ) sqlite3VdbeCountChanges(v); 592 sqlite3BeginWriteOperation(pParse, pSelect || pTrigger, iDb); 593 594 #ifndef SQLITE_OMIT_XFER_OPT 595 /* If the statement is of the form 596 ** 597 ** INSERT INTO <table1> SELECT * FROM <table2>; 598 ** 599 ** Then special optimizations can be applied that make the transfer 600 ** very fast and which reduce fragmentation of indices. 601 ** 602 ** This is the 2nd template. 603 */ 604 if( pColumn==0 && xferOptimization(pParse, pTab, pSelect, onError, iDb) ){ 605 assert( !pTrigger ); 606 assert( pList==0 ); 607 goto insert_end; 608 } 609 #endif /* SQLITE_OMIT_XFER_OPT */ 610 611 /* If this is an AUTOINCREMENT table, look up the sequence number in the 612 ** sqlite_sequence table and store it in memory cell regAutoinc. 613 */ 614 regAutoinc = autoIncBegin(pParse, iDb, pTab); 615 616 /* Allocate registers for holding the rowid of the new row, 617 ** the content of the new row, and the assembled row record. 618 */ 619 regRowid = regIns = pParse->nMem+1; 620 pParse->nMem += pTab->nCol + 1; 621 if( IsVirtual(pTab) ){ 622 regRowid++; 623 pParse->nMem++; 624 } 625 regData = regRowid+1; 626 627 /* If the INSERT statement included an IDLIST term, then make sure 628 ** all elements of the IDLIST really are columns of the table and 629 ** remember the column indices. 630 ** 631 ** If the table has an INTEGER PRIMARY KEY column and that column 632 ** is named in the IDLIST, then record in the ipkColumn variable 633 ** the index into IDLIST of the primary key column. ipkColumn is 634 ** the index of the primary key as it appears in IDLIST, not as 635 ** is appears in the original table. (The index of the INTEGER 636 ** PRIMARY KEY in the original table is pTab->iPKey.) 637 */ 638 bIdListInOrder = (pTab->tabFlags & TF_OOOHidden)==0; 639 if( pColumn ){ 640 for(i=0; i<pColumn->nId; i++){ 641 pColumn->a[i].idx = -1; 642 } 643 for(i=0; i<pColumn->nId; i++){ 644 for(j=0; j<pTab->nCol; j++){ 645 if( sqlite3StrICmp(pColumn->a[i].zName, pTab->aCol[j].zName)==0 ){ 646 pColumn->a[i].idx = j; 647 if( i!=j ) bIdListInOrder = 0; 648 if( j==pTab->iPKey ){ 649 ipkColumn = i; assert( !withoutRowid ); 650 } 651 break; 652 } 653 } 654 if( j>=pTab->nCol ){ 655 if( sqlite3IsRowid(pColumn->a[i].zName) && !withoutRowid ){ 656 ipkColumn = i; 657 bIdListInOrder = 0; 658 }else{ 659 sqlite3ErrorMsg(pParse, "table %S has no column named %s", 660 pTabList, 0, pColumn->a[i].zName); 661 pParse->checkSchema = 1; 662 goto insert_cleanup; 663 } 664 } 665 } 666 } 667 668 /* Figure out how many columns of data are supplied. If the data 669 ** is coming from a SELECT statement, then generate a co-routine that 670 ** produces a single row of the SELECT on each invocation. The 671 ** co-routine is the common header to the 3rd and 4th templates. 672 */ 673 if( pSelect ){ 674 /* Data is coming from a SELECT or from a multi-row VALUES clause. 675 ** Generate a co-routine to run the SELECT. */ 676 int regYield; /* Register holding co-routine entry-point */ 677 int addrTop; /* Top of the co-routine */ 678 int rc; /* Result code */ 679 680 regYield = ++pParse->nMem; 681 addrTop = sqlite3VdbeCurrentAddr(v) + 1; 682 sqlite3VdbeAddOp3(v, OP_InitCoroutine, regYield, 0, addrTop); 683 sqlite3SelectDestInit(&dest, SRT_Coroutine, regYield); 684 dest.iSdst = bIdListInOrder ? regData : 0; 685 dest.nSdst = pTab->nCol; 686 rc = sqlite3Select(pParse, pSelect, &dest); 687 regFromSelect = dest.iSdst; 688 if( rc || db->mallocFailed || pParse->nErr ) goto insert_cleanup; 689 sqlite3VdbeEndCoroutine(v, regYield); 690 sqlite3VdbeJumpHere(v, addrTop - 1); /* label B: */ 691 assert( pSelect->pEList ); 692 nColumn = pSelect->pEList->nExpr; 693 694 /* Set useTempTable to TRUE if the result of the SELECT statement 695 ** should be written into a temporary table (template 4). Set to 696 ** FALSE if each output row of the SELECT can be written directly into 697 ** the destination table (template 3). 698 ** 699 ** A temp table must be used if the table being updated is also one 700 ** of the tables being read by the SELECT statement. Also use a 701 ** temp table in the case of row triggers. 702 */ 703 if( pTrigger || readsTable(pParse, iDb, pTab) ){ 704 useTempTable = 1; 705 } 706 707 if( useTempTable ){ 708 /* Invoke the coroutine to extract information from the SELECT 709 ** and add it to a transient table srcTab. The code generated 710 ** here is from the 4th template: 711 ** 712 ** B: open temp table 713 ** L: yield X, goto M at EOF 714 ** insert row from R..R+n into temp table 715 ** goto L 716 ** M: ... 717 */ 718 int regRec; /* Register to hold packed record */ 719 int regTempRowid; /* Register to hold temp table ROWID */ 720 int addrL; /* Label "L" */ 721 722 srcTab = pParse->nTab++; 723 regRec = sqlite3GetTempReg(pParse); 724 regTempRowid = sqlite3GetTempReg(pParse); 725 sqlite3VdbeAddOp2(v, OP_OpenEphemeral, srcTab, nColumn); 726 addrL = sqlite3VdbeAddOp1(v, OP_Yield, dest.iSDParm); VdbeCoverage(v); 727 sqlite3VdbeAddOp3(v, OP_MakeRecord, regFromSelect, nColumn, regRec); 728 sqlite3VdbeAddOp2(v, OP_NewRowid, srcTab, regTempRowid); 729 sqlite3VdbeAddOp3(v, OP_Insert, srcTab, regRec, regTempRowid); 730 sqlite3VdbeGoto(v, addrL); 731 sqlite3VdbeJumpHere(v, addrL); 732 sqlite3ReleaseTempReg(pParse, regRec); 733 sqlite3ReleaseTempReg(pParse, regTempRowid); 734 } 735 }else{ 736 /* This is the case if the data for the INSERT is coming from a 737 ** single-row VALUES clause 738 */ 739 NameContext sNC; 740 memset(&sNC, 0, sizeof(sNC)); 741 sNC.pParse = pParse; 742 srcTab = -1; 743 assert( useTempTable==0 ); 744 if( pList ){ 745 nColumn = pList->nExpr; 746 if( sqlite3ResolveExprListNames(&sNC, pList) ){ 747 goto insert_cleanup; 748 } 749 }else{ 750 nColumn = 0; 751 } 752 } 753 754 /* If there is no IDLIST term but the table has an integer primary 755 ** key, the set the ipkColumn variable to the integer primary key 756 ** column index in the original table definition. 757 */ 758 if( pColumn==0 && nColumn>0 ){ 759 ipkColumn = pTab->iPKey; 760 } 761 762 /* Make sure the number of columns in the source data matches the number 763 ** of columns to be inserted into the table. 764 */ 765 for(i=0; i<pTab->nCol; i++){ 766 nHidden += (IsHiddenColumn(&pTab->aCol[i]) ? 1 : 0); 767 } 768 if( pColumn==0 && nColumn && nColumn!=(pTab->nCol-nHidden) ){ 769 sqlite3ErrorMsg(pParse, 770 "table %S has %d columns but %d values were supplied", 771 pTabList, 0, pTab->nCol-nHidden, nColumn); 772 goto insert_cleanup; 773 } 774 if( pColumn!=0 && nColumn!=pColumn->nId ){ 775 sqlite3ErrorMsg(pParse, "%d values for %d columns", nColumn, pColumn->nId); 776 goto insert_cleanup; 777 } 778 779 /* Initialize the count of rows to be inserted 780 */ 781 if( db->flags & SQLITE_CountRows ){ 782 regRowCount = ++pParse->nMem; 783 sqlite3VdbeAddOp2(v, OP_Integer, 0, regRowCount); 784 } 785 786 /* If this is not a view, open the table and and all indices */ 787 if( !isView ){ 788 int nIdx; 789 nIdx = sqlite3OpenTableAndIndices(pParse, pTab, OP_OpenWrite, 0, -1, 0, 790 &iDataCur, &iIdxCur); 791 aRegIdx = sqlite3DbMallocRawNN(db, sizeof(int)*(nIdx+1)); 792 if( aRegIdx==0 ){ 793 goto insert_cleanup; 794 } 795 for(i=0, pIdx=pTab->pIndex; i<nIdx; pIdx=pIdx->pNext, i++){ 796 assert( pIdx ); 797 aRegIdx[i] = ++pParse->nMem; 798 pParse->nMem += pIdx->nColumn; 799 } 800 } 801 802 /* This is the top of the main insertion loop */ 803 if( useTempTable ){ 804 /* This block codes the top of loop only. The complete loop is the 805 ** following pseudocode (template 4): 806 ** 807 ** rewind temp table, if empty goto D 808 ** C: loop over rows of intermediate table 809 ** transfer values form intermediate table into <table> 810 ** end loop 811 ** D: ... 812 */ 813 addrInsTop = sqlite3VdbeAddOp1(v, OP_Rewind, srcTab); VdbeCoverage(v); 814 addrCont = sqlite3VdbeCurrentAddr(v); 815 }else if( pSelect ){ 816 /* This block codes the top of loop only. The complete loop is the 817 ** following pseudocode (template 3): 818 ** 819 ** C: yield X, at EOF goto D 820 ** insert the select result into <table> from R..R+n 821 ** goto C 822 ** D: ... 823 */ 824 addrInsTop = addrCont = sqlite3VdbeAddOp1(v, OP_Yield, dest.iSDParm); 825 VdbeCoverage(v); 826 } 827 828 /* Run the BEFORE and INSTEAD OF triggers, if there are any 829 */ 830 endOfLoop = sqlite3VdbeMakeLabel(v); 831 if( tmask & TRIGGER_BEFORE ){ 832 int regCols = sqlite3GetTempRange(pParse, pTab->nCol+1); 833 834 /* build the NEW.* reference row. Note that if there is an INTEGER 835 ** PRIMARY KEY into which a NULL is being inserted, that NULL will be 836 ** translated into a unique ID for the row. But on a BEFORE trigger, 837 ** we do not know what the unique ID will be (because the insert has 838 ** not happened yet) so we substitute a rowid of -1 839 */ 840 if( ipkColumn<0 ){ 841 sqlite3VdbeAddOp2(v, OP_Integer, -1, regCols); 842 }else{ 843 int addr1; 844 assert( !withoutRowid ); 845 if( useTempTable ){ 846 sqlite3VdbeAddOp3(v, OP_Column, srcTab, ipkColumn, regCols); 847 }else{ 848 assert( pSelect==0 ); /* Otherwise useTempTable is true */ 849 sqlite3ExprCode(pParse, pList->a[ipkColumn].pExpr, regCols); 850 } 851 addr1 = sqlite3VdbeAddOp1(v, OP_NotNull, regCols); VdbeCoverage(v); 852 sqlite3VdbeAddOp2(v, OP_Integer, -1, regCols); 853 sqlite3VdbeJumpHere(v, addr1); 854 sqlite3VdbeAddOp1(v, OP_MustBeInt, regCols); VdbeCoverage(v); 855 } 856 857 /* Cannot have triggers on a virtual table. If it were possible, 858 ** this block would have to account for hidden column. 859 */ 860 assert( !IsVirtual(pTab) ); 861 862 /* Create the new column data 863 */ 864 for(i=j=0; i<pTab->nCol; i++){ 865 if( pColumn ){ 866 for(j=0; j<pColumn->nId; j++){ 867 if( pColumn->a[j].idx==i ) break; 868 } 869 } 870 if( (!useTempTable && !pList) || (pColumn && j>=pColumn->nId) 871 || (pColumn==0 && IsOrdinaryHiddenColumn(&pTab->aCol[i])) ){ 872 sqlite3ExprCode(pParse, pTab->aCol[i].pDflt, regCols+i+1); 873 }else if( useTempTable ){ 874 sqlite3VdbeAddOp3(v, OP_Column, srcTab, j, regCols+i+1); 875 }else{ 876 assert( pSelect==0 ); /* Otherwise useTempTable is true */ 877 sqlite3ExprCodeAndCache(pParse, pList->a[j].pExpr, regCols+i+1); 878 } 879 if( pColumn==0 && !IsOrdinaryHiddenColumn(&pTab->aCol[i]) ) j++; 880 } 881 882 /* If this is an INSERT on a view with an INSTEAD OF INSERT trigger, 883 ** do not attempt any conversions before assembling the record. 884 ** If this is a real table, attempt conversions as required by the 885 ** table column affinities. 886 */ 887 if( !isView ){ 888 sqlite3TableAffinity(v, pTab, regCols+1); 889 } 890 891 /* Fire BEFORE or INSTEAD OF triggers */ 892 sqlite3CodeRowTrigger(pParse, pTrigger, TK_INSERT, 0, TRIGGER_BEFORE, 893 pTab, regCols-pTab->nCol-1, onError, endOfLoop); 894 895 sqlite3ReleaseTempRange(pParse, regCols, pTab->nCol+1); 896 } 897 898 /* Compute the content of the next row to insert into a range of 899 ** registers beginning at regIns. 900 */ 901 if( !isView ){ 902 if( IsVirtual(pTab) ){ 903 /* The row that the VUpdate opcode will delete: none */ 904 sqlite3VdbeAddOp2(v, OP_Null, 0, regIns); 905 } 906 if( ipkColumn>=0 ){ 907 if( useTempTable ){ 908 sqlite3VdbeAddOp3(v, OP_Column, srcTab, ipkColumn, regRowid); 909 }else if( pSelect ){ 910 sqlite3VdbeAddOp2(v, OP_Copy, regFromSelect+ipkColumn, regRowid); 911 }else{ 912 VdbeOp *pOp; 913 sqlite3ExprCode(pParse, pList->a[ipkColumn].pExpr, regRowid); 914 pOp = sqlite3VdbeGetOp(v, -1); 915 if( ALWAYS(pOp) && pOp->opcode==OP_Null && !IsVirtual(pTab) ){ 916 appendFlag = 1; 917 pOp->opcode = OP_NewRowid; 918 pOp->p1 = iDataCur; 919 pOp->p2 = regRowid; 920 pOp->p3 = regAutoinc; 921 } 922 } 923 /* If the PRIMARY KEY expression is NULL, then use OP_NewRowid 924 ** to generate a unique primary key value. 925 */ 926 if( !appendFlag ){ 927 int addr1; 928 if( !IsVirtual(pTab) ){ 929 addr1 = sqlite3VdbeAddOp1(v, OP_NotNull, regRowid); VdbeCoverage(v); 930 sqlite3VdbeAddOp3(v, OP_NewRowid, iDataCur, regRowid, regAutoinc); 931 sqlite3VdbeJumpHere(v, addr1); 932 }else{ 933 addr1 = sqlite3VdbeCurrentAddr(v); 934 sqlite3VdbeAddOp2(v, OP_IsNull, regRowid, addr1+2); VdbeCoverage(v); 935 } 936 sqlite3VdbeAddOp1(v, OP_MustBeInt, regRowid); VdbeCoverage(v); 937 } 938 }else if( IsVirtual(pTab) || withoutRowid ){ 939 sqlite3VdbeAddOp2(v, OP_Null, 0, regRowid); 940 }else{ 941 sqlite3VdbeAddOp3(v, OP_NewRowid, iDataCur, regRowid, regAutoinc); 942 appendFlag = 1; 943 } 944 autoIncStep(pParse, regAutoinc, regRowid); 945 946 /* Compute data for all columns of the new entry, beginning 947 ** with the first column. 948 */ 949 nHidden = 0; 950 for(i=0; i<pTab->nCol; i++){ 951 int iRegStore = regRowid+1+i; 952 if( i==pTab->iPKey ){ 953 /* The value of the INTEGER PRIMARY KEY column is always a NULL. 954 ** Whenever this column is read, the rowid will be substituted 955 ** in its place. Hence, fill this column with a NULL to avoid 956 ** taking up data space with information that will never be used. 957 ** As there may be shallow copies of this value, make it a soft-NULL */ 958 sqlite3VdbeAddOp1(v, OP_SoftNull, iRegStore); 959 continue; 960 } 961 if( pColumn==0 ){ 962 if( IsHiddenColumn(&pTab->aCol[i]) ){ 963 j = -1; 964 nHidden++; 965 }else{ 966 j = i - nHidden; 967 } 968 }else{ 969 for(j=0; j<pColumn->nId; j++){ 970 if( pColumn->a[j].idx==i ) break; 971 } 972 } 973 if( j<0 || nColumn==0 || (pColumn && j>=pColumn->nId) ){ 974 sqlite3ExprCodeFactorable(pParse, pTab->aCol[i].pDflt, iRegStore); 975 }else if( useTempTable ){ 976 sqlite3VdbeAddOp3(v, OP_Column, srcTab, j, iRegStore); 977 }else if( pSelect ){ 978 if( regFromSelect!=regData ){ 979 sqlite3VdbeAddOp2(v, OP_SCopy, regFromSelect+j, iRegStore); 980 } 981 }else{ 982 sqlite3ExprCode(pParse, pList->a[j].pExpr, iRegStore); 983 } 984 } 985 986 /* Generate code to check constraints and generate index keys and 987 ** do the insertion. 988 */ 989 #ifndef SQLITE_OMIT_VIRTUALTABLE 990 if( IsVirtual(pTab) ){ 991 const char *pVTab = (const char *)sqlite3GetVTable(db, pTab); 992 sqlite3VtabMakeWritable(pParse, pTab); 993 sqlite3VdbeAddOp4(v, OP_VUpdate, 1, pTab->nCol+2, regIns, pVTab, P4_VTAB); 994 sqlite3VdbeChangeP5(v, onError==OE_Default ? OE_Abort : onError); 995 sqlite3MayAbort(pParse); 996 }else 997 #endif 998 { 999 int isReplace; /* Set to true if constraints may cause a replace */ 1000 int bUseSeek; /* True to use OPFLAG_SEEKRESULT */ 1001 sqlite3GenerateConstraintChecks(pParse, pTab, aRegIdx, iDataCur, iIdxCur, 1002 regIns, 0, ipkColumn>=0, onError, endOfLoop, &isReplace, 0 1003 ); 1004 sqlite3FkCheck(pParse, pTab, 0, regIns, 0, 0); 1005 1006 /* Set the OPFLAG_USESEEKRESULT flag if either (a) there are no REPLACE 1007 ** constraints or (b) there are no triggers and this table is not a 1008 ** parent table in a foreign key constraint. It is safe to set the 1009 ** flag in the second case as if any REPLACE constraint is hit, an 1010 ** OP_Delete or OP_IdxDelete instruction will be executed on each 1011 ** cursor that is disturbed. And these instructions both clear the 1012 ** VdbeCursor.seekResult variable, disabling the OPFLAG_USESEEKRESULT 1013 ** functionality. */ 1014 bUseSeek = (isReplace==0 || (pTrigger==0 && 1015 ((db->flags & SQLITE_ForeignKeys)==0 || sqlite3FkReferences(pTab)==0) 1016 )); 1017 sqlite3CompleteInsertion(pParse, pTab, iDataCur, iIdxCur, 1018 regIns, aRegIdx, 0, appendFlag, bUseSeek 1019 ); 1020 } 1021 } 1022 1023 /* Update the count of rows that are inserted 1024 */ 1025 if( (db->flags & SQLITE_CountRows)!=0 ){ 1026 sqlite3VdbeAddOp2(v, OP_AddImm, regRowCount, 1); 1027 } 1028 1029 if( pTrigger ){ 1030 /* Code AFTER triggers */ 1031 sqlite3CodeRowTrigger(pParse, pTrigger, TK_INSERT, 0, TRIGGER_AFTER, 1032 pTab, regData-2-pTab->nCol, onError, endOfLoop); 1033 } 1034 1035 /* The bottom of the main insertion loop, if the data source 1036 ** is a SELECT statement. 1037 */ 1038 sqlite3VdbeResolveLabel(v, endOfLoop); 1039 if( useTempTable ){ 1040 sqlite3VdbeAddOp2(v, OP_Next, srcTab, addrCont); VdbeCoverage(v); 1041 sqlite3VdbeJumpHere(v, addrInsTop); 1042 sqlite3VdbeAddOp1(v, OP_Close, srcTab); 1043 }else if( pSelect ){ 1044 sqlite3VdbeGoto(v, addrCont); 1045 sqlite3VdbeJumpHere(v, addrInsTop); 1046 } 1047 1048 insert_end: 1049 /* Update the sqlite_sequence table by storing the content of the 1050 ** maximum rowid counter values recorded while inserting into 1051 ** autoincrement tables. 1052 */ 1053 if( pParse->nested==0 && pParse->pTriggerTab==0 ){ 1054 sqlite3AutoincrementEnd(pParse); 1055 } 1056 1057 /* 1058 ** Return the number of rows inserted. If this routine is 1059 ** generating code because of a call to sqlite3NestedParse(), do not 1060 ** invoke the callback function. 1061 */ 1062 if( (db->flags&SQLITE_CountRows) && !pParse->nested && !pParse->pTriggerTab ){ 1063 sqlite3VdbeAddOp2(v, OP_ResultRow, regRowCount, 1); 1064 sqlite3VdbeSetNumCols(v, 1); 1065 sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows inserted", SQLITE_STATIC); 1066 } 1067 1068 insert_cleanup: 1069 sqlite3SrcListDelete(db, pTabList); 1070 sqlite3ExprListDelete(db, pList); 1071 sqlite3SelectDelete(db, pSelect); 1072 sqlite3IdListDelete(db, pColumn); 1073 sqlite3DbFree(db, aRegIdx); 1074 } 1075 1076 /* Make sure "isView" and other macros defined above are undefined. Otherwise 1077 ** they may interfere with compilation of other functions in this file 1078 ** (or in another file, if this file becomes part of the amalgamation). */ 1079 #ifdef isView 1080 #undef isView 1081 #endif 1082 #ifdef pTrigger 1083 #undef pTrigger 1084 #endif 1085 #ifdef tmask 1086 #undef tmask 1087 #endif 1088 1089 /* 1090 ** Meanings of bits in of pWalker->eCode for checkConstraintUnchanged() 1091 */ 1092 #define CKCNSTRNT_COLUMN 0x01 /* CHECK constraint uses a changing column */ 1093 #define CKCNSTRNT_ROWID 0x02 /* CHECK constraint references the ROWID */ 1094 1095 /* This is the Walker callback from checkConstraintUnchanged(). Set 1096 ** bit 0x01 of pWalker->eCode if 1097 ** pWalker->eCode to 0 if this expression node references any of the 1098 ** columns that are being modifed by an UPDATE statement. 1099 */ 1100 static int checkConstraintExprNode(Walker *pWalker, Expr *pExpr){ 1101 if( pExpr->op==TK_COLUMN ){ 1102 assert( pExpr->iColumn>=0 || pExpr->iColumn==-1 ); 1103 if( pExpr->iColumn>=0 ){ 1104 if( pWalker->u.aiCol[pExpr->iColumn]>=0 ){ 1105 pWalker->eCode |= CKCNSTRNT_COLUMN; 1106 } 1107 }else{ 1108 pWalker->eCode |= CKCNSTRNT_ROWID; 1109 } 1110 } 1111 return WRC_Continue; 1112 } 1113 1114 /* 1115 ** pExpr is a CHECK constraint on a row that is being UPDATE-ed. The 1116 ** only columns that are modified by the UPDATE are those for which 1117 ** aiChng[i]>=0, and also the ROWID is modified if chngRowid is true. 1118 ** 1119 ** Return true if CHECK constraint pExpr does not use any of the 1120 ** changing columns (or the rowid if it is changing). In other words, 1121 ** return true if this CHECK constraint can be skipped when validating 1122 ** the new row in the UPDATE statement. 1123 */ 1124 static int checkConstraintUnchanged(Expr *pExpr, int *aiChng, int chngRowid){ 1125 Walker w; 1126 memset(&w, 0, sizeof(w)); 1127 w.eCode = 0; 1128 w.xExprCallback = checkConstraintExprNode; 1129 w.u.aiCol = aiChng; 1130 sqlite3WalkExpr(&w, pExpr); 1131 if( !chngRowid ){ 1132 testcase( (w.eCode & CKCNSTRNT_ROWID)!=0 ); 1133 w.eCode &= ~CKCNSTRNT_ROWID; 1134 } 1135 testcase( w.eCode==0 ); 1136 testcase( w.eCode==CKCNSTRNT_COLUMN ); 1137 testcase( w.eCode==CKCNSTRNT_ROWID ); 1138 testcase( w.eCode==(CKCNSTRNT_ROWID|CKCNSTRNT_COLUMN) ); 1139 return !w.eCode; 1140 } 1141 1142 /* 1143 ** Generate code to do constraint checks prior to an INSERT or an UPDATE 1144 ** on table pTab. 1145 ** 1146 ** The regNewData parameter is the first register in a range that contains 1147 ** the data to be inserted or the data after the update. There will be 1148 ** pTab->nCol+1 registers in this range. The first register (the one 1149 ** that regNewData points to) will contain the new rowid, or NULL in the 1150 ** case of a WITHOUT ROWID table. The second register in the range will 1151 ** contain the content of the first table column. The third register will 1152 ** contain the content of the second table column. And so forth. 1153 ** 1154 ** The regOldData parameter is similar to regNewData except that it contains 1155 ** the data prior to an UPDATE rather than afterwards. regOldData is zero 1156 ** for an INSERT. This routine can distinguish between UPDATE and INSERT by 1157 ** checking regOldData for zero. 1158 ** 1159 ** For an UPDATE, the pkChng boolean is true if the true primary key (the 1160 ** rowid for a normal table or the PRIMARY KEY for a WITHOUT ROWID table) 1161 ** might be modified by the UPDATE. If pkChng is false, then the key of 1162 ** the iDataCur content table is guaranteed to be unchanged by the UPDATE. 1163 ** 1164 ** For an INSERT, the pkChng boolean indicates whether or not the rowid 1165 ** was explicitly specified as part of the INSERT statement. If pkChng 1166 ** is zero, it means that the either rowid is computed automatically or 1167 ** that the table is a WITHOUT ROWID table and has no rowid. On an INSERT, 1168 ** pkChng will only be true if the INSERT statement provides an integer 1169 ** value for either the rowid column or its INTEGER PRIMARY KEY alias. 1170 ** 1171 ** The code generated by this routine will store new index entries into 1172 ** registers identified by aRegIdx[]. No index entry is created for 1173 ** indices where aRegIdx[i]==0. The order of indices in aRegIdx[] is 1174 ** the same as the order of indices on the linked list of indices 1175 ** at pTab->pIndex. 1176 ** 1177 ** The caller must have already opened writeable cursors on the main 1178 ** table and all applicable indices (that is to say, all indices for which 1179 ** aRegIdx[] is not zero). iDataCur is the cursor for the main table when 1180 ** inserting or updating a rowid table, or the cursor for the PRIMARY KEY 1181 ** index when operating on a WITHOUT ROWID table. iIdxCur is the cursor 1182 ** for the first index in the pTab->pIndex list. Cursors for other indices 1183 ** are at iIdxCur+N for the N-th element of the pTab->pIndex list. 1184 ** 1185 ** This routine also generates code to check constraints. NOT NULL, 1186 ** CHECK, and UNIQUE constraints are all checked. If a constraint fails, 1187 ** then the appropriate action is performed. There are five possible 1188 ** actions: ROLLBACK, ABORT, FAIL, REPLACE, and IGNORE. 1189 ** 1190 ** Constraint type Action What Happens 1191 ** --------------- ---------- ---------------------------------------- 1192 ** any ROLLBACK The current transaction is rolled back and 1193 ** sqlite3_step() returns immediately with a 1194 ** return code of SQLITE_CONSTRAINT. 1195 ** 1196 ** any ABORT Back out changes from the current command 1197 ** only (do not do a complete rollback) then 1198 ** cause sqlite3_step() to return immediately 1199 ** with SQLITE_CONSTRAINT. 1200 ** 1201 ** any FAIL Sqlite3_step() returns immediately with a 1202 ** return code of SQLITE_CONSTRAINT. The 1203 ** transaction is not rolled back and any 1204 ** changes to prior rows are retained. 1205 ** 1206 ** any IGNORE The attempt in insert or update the current 1207 ** row is skipped, without throwing an error. 1208 ** Processing continues with the next row. 1209 ** (There is an immediate jump to ignoreDest.) 1210 ** 1211 ** NOT NULL REPLACE The NULL value is replace by the default 1212 ** value for that column. If the default value 1213 ** is NULL, the action is the same as ABORT. 1214 ** 1215 ** UNIQUE REPLACE The other row that conflicts with the row 1216 ** being inserted is removed. 1217 ** 1218 ** CHECK REPLACE Illegal. The results in an exception. 1219 ** 1220 ** Which action to take is determined by the overrideError parameter. 1221 ** Or if overrideError==OE_Default, then the pParse->onError parameter 1222 ** is used. Or if pParse->onError==OE_Default then the onError value 1223 ** for the constraint is used. 1224 */ 1225 void sqlite3GenerateConstraintChecks( 1226 Parse *pParse, /* The parser context */ 1227 Table *pTab, /* The table being inserted or updated */ 1228 int *aRegIdx, /* Use register aRegIdx[i] for index i. 0 for unused */ 1229 int iDataCur, /* Canonical data cursor (main table or PK index) */ 1230 int iIdxCur, /* First index cursor */ 1231 int regNewData, /* First register in a range holding values to insert */ 1232 int regOldData, /* Previous content. 0 for INSERTs */ 1233 u8 pkChng, /* Non-zero if the rowid or PRIMARY KEY changed */ 1234 u8 overrideError, /* Override onError to this if not OE_Default */ 1235 int ignoreDest, /* Jump to this label on an OE_Ignore resolution */ 1236 int *pbMayReplace, /* OUT: Set to true if constraint may cause a replace */ 1237 int *aiChng /* column i is unchanged if aiChng[i]<0 */ 1238 ){ 1239 Vdbe *v; /* VDBE under constrution */ 1240 Index *pIdx; /* Pointer to one of the indices */ 1241 Index *pPk = 0; /* The PRIMARY KEY index */ 1242 sqlite3 *db; /* Database connection */ 1243 int i; /* loop counter */ 1244 int ix; /* Index loop counter */ 1245 int nCol; /* Number of columns */ 1246 int onError; /* Conflict resolution strategy */ 1247 int addr1; /* Address of jump instruction */ 1248 int seenReplace = 0; /* True if REPLACE is used to resolve INT PK conflict */ 1249 int nPkField; /* Number of fields in PRIMARY KEY. 1 for ROWID tables */ 1250 int ipkTop = 0; /* Top of the rowid change constraint check */ 1251 int ipkBottom = 0; /* Bottom of the rowid change constraint check */ 1252 u8 isUpdate; /* True if this is an UPDATE operation */ 1253 u8 bAffinityDone = 0; /* True if the OP_Affinity operation has been run */ 1254 1255 isUpdate = regOldData!=0; 1256 db = pParse->db; 1257 v = sqlite3GetVdbe(pParse); 1258 assert( v!=0 ); 1259 assert( pTab->pSelect==0 ); /* This table is not a VIEW */ 1260 nCol = pTab->nCol; 1261 1262 /* pPk is the PRIMARY KEY index for WITHOUT ROWID tables and NULL for 1263 ** normal rowid tables. nPkField is the number of key fields in the 1264 ** pPk index or 1 for a rowid table. In other words, nPkField is the 1265 ** number of fields in the true primary key of the table. */ 1266 if( HasRowid(pTab) ){ 1267 pPk = 0; 1268 nPkField = 1; 1269 }else{ 1270 pPk = sqlite3PrimaryKeyIndex(pTab); 1271 nPkField = pPk->nKeyCol; 1272 } 1273 1274 /* Record that this module has started */ 1275 VdbeModuleComment((v, "BEGIN: GenCnstCks(%d,%d,%d,%d,%d)", 1276 iDataCur, iIdxCur, regNewData, regOldData, pkChng)); 1277 1278 /* Test all NOT NULL constraints. 1279 */ 1280 for(i=0; i<nCol; i++){ 1281 if( i==pTab->iPKey ){ 1282 continue; /* ROWID is never NULL */ 1283 } 1284 if( aiChng && aiChng[i]<0 ){ 1285 /* Don't bother checking for NOT NULL on columns that do not change */ 1286 continue; 1287 } 1288 onError = pTab->aCol[i].notNull; 1289 if( onError==OE_None ) continue; /* This column is allowed to be NULL */ 1290 if( overrideError!=OE_Default ){ 1291 onError = overrideError; 1292 }else if( onError==OE_Default ){ 1293 onError = OE_Abort; 1294 } 1295 if( onError==OE_Replace && pTab->aCol[i].pDflt==0 ){ 1296 onError = OE_Abort; 1297 } 1298 assert( onError==OE_Rollback || onError==OE_Abort || onError==OE_Fail 1299 || onError==OE_Ignore || onError==OE_Replace ); 1300 switch( onError ){ 1301 case OE_Abort: 1302 sqlite3MayAbort(pParse); 1303 /* Fall through */ 1304 case OE_Rollback: 1305 case OE_Fail: { 1306 char *zMsg = sqlite3MPrintf(db, "%s.%s", pTab->zName, 1307 pTab->aCol[i].zName); 1308 sqlite3VdbeAddOp3(v, OP_HaltIfNull, SQLITE_CONSTRAINT_NOTNULL, onError, 1309 regNewData+1+i); 1310 sqlite3VdbeAppendP4(v, zMsg, P4_DYNAMIC); 1311 sqlite3VdbeChangeP5(v, P5_ConstraintNotNull); 1312 VdbeCoverage(v); 1313 break; 1314 } 1315 case OE_Ignore: { 1316 sqlite3VdbeAddOp2(v, OP_IsNull, regNewData+1+i, ignoreDest); 1317 VdbeCoverage(v); 1318 break; 1319 } 1320 default: { 1321 assert( onError==OE_Replace ); 1322 addr1 = sqlite3VdbeAddOp1(v, OP_NotNull, regNewData+1+i); 1323 VdbeCoverage(v); 1324 sqlite3ExprCode(pParse, pTab->aCol[i].pDflt, regNewData+1+i); 1325 sqlite3VdbeJumpHere(v, addr1); 1326 break; 1327 } 1328 } 1329 } 1330 1331 /* Test all CHECK constraints 1332 */ 1333 #ifndef SQLITE_OMIT_CHECK 1334 if( pTab->pCheck && (db->flags & SQLITE_IgnoreChecks)==0 ){ 1335 ExprList *pCheck = pTab->pCheck; 1336 pParse->iSelfTab = -(regNewData+1); 1337 onError = overrideError!=OE_Default ? overrideError : OE_Abort; 1338 for(i=0; i<pCheck->nExpr; i++){ 1339 int allOk; 1340 Expr *pExpr = pCheck->a[i].pExpr; 1341 if( aiChng && checkConstraintUnchanged(pExpr, aiChng, pkChng) ) continue; 1342 allOk = sqlite3VdbeMakeLabel(v); 1343 sqlite3ExprIfTrue(pParse, pExpr, allOk, SQLITE_JUMPIFNULL); 1344 if( onError==OE_Ignore ){ 1345 sqlite3VdbeGoto(v, ignoreDest); 1346 }else{ 1347 char *zName = pCheck->a[i].zName; 1348 if( zName==0 ) zName = pTab->zName; 1349 if( onError==OE_Replace ) onError = OE_Abort; /* IMP: R-15569-63625 */ 1350 sqlite3HaltConstraint(pParse, SQLITE_CONSTRAINT_CHECK, 1351 onError, zName, P4_TRANSIENT, 1352 P5_ConstraintCheck); 1353 } 1354 sqlite3VdbeResolveLabel(v, allOk); 1355 } 1356 pParse->iSelfTab = 0; 1357 } 1358 #endif /* !defined(SQLITE_OMIT_CHECK) */ 1359 1360 /* If rowid is changing, make sure the new rowid does not previously 1361 ** exist in the table. 1362 */ 1363 if( pkChng && pPk==0 ){ 1364 int addrRowidOk = sqlite3VdbeMakeLabel(v); 1365 1366 /* Figure out what action to take in case of a rowid collision */ 1367 onError = pTab->keyConf; 1368 if( overrideError!=OE_Default ){ 1369 onError = overrideError; 1370 }else if( onError==OE_Default ){ 1371 onError = OE_Abort; 1372 } 1373 1374 if( isUpdate ){ 1375 /* pkChng!=0 does not mean that the rowid has changed, only that 1376 ** it might have changed. Skip the conflict logic below if the rowid 1377 ** is unchanged. */ 1378 sqlite3VdbeAddOp3(v, OP_Eq, regNewData, addrRowidOk, regOldData); 1379 sqlite3VdbeChangeP5(v, SQLITE_NOTNULL); 1380 VdbeCoverage(v); 1381 } 1382 1383 /* If the response to a rowid conflict is REPLACE but the response 1384 ** to some other UNIQUE constraint is FAIL or IGNORE, then we need 1385 ** to defer the running of the rowid conflict checking until after 1386 ** the UNIQUE constraints have run. 1387 */ 1388 if( onError==OE_Replace && overrideError!=OE_Replace ){ 1389 for(pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext){ 1390 if( pIdx->onError==OE_Ignore || pIdx->onError==OE_Fail ){ 1391 ipkTop = sqlite3VdbeAddOp0(v, OP_Goto); 1392 break; 1393 } 1394 } 1395 } 1396 1397 /* Check to see if the new rowid already exists in the table. Skip 1398 ** the following conflict logic if it does not. */ 1399 sqlite3VdbeAddOp3(v, OP_NotExists, iDataCur, addrRowidOk, regNewData); 1400 VdbeCoverage(v); 1401 1402 /* Generate code that deals with a rowid collision */ 1403 switch( onError ){ 1404 default: { 1405 onError = OE_Abort; 1406 /* Fall thru into the next case */ 1407 } 1408 case OE_Rollback: 1409 case OE_Abort: 1410 case OE_Fail: { 1411 sqlite3RowidConstraint(pParse, onError, pTab); 1412 break; 1413 } 1414 case OE_Replace: { 1415 /* If there are DELETE triggers on this table and the 1416 ** recursive-triggers flag is set, call GenerateRowDelete() to 1417 ** remove the conflicting row from the table. This will fire 1418 ** the triggers and remove both the table and index b-tree entries. 1419 ** 1420 ** Otherwise, if there are no triggers or the recursive-triggers 1421 ** flag is not set, but the table has one or more indexes, call 1422 ** GenerateRowIndexDelete(). This removes the index b-tree entries 1423 ** only. The table b-tree entry will be replaced by the new entry 1424 ** when it is inserted. 1425 ** 1426 ** If either GenerateRowDelete() or GenerateRowIndexDelete() is called, 1427 ** also invoke MultiWrite() to indicate that this VDBE may require 1428 ** statement rollback (if the statement is aborted after the delete 1429 ** takes place). Earlier versions called sqlite3MultiWrite() regardless, 1430 ** but being more selective here allows statements like: 1431 ** 1432 ** REPLACE INTO t(rowid) VALUES($newrowid) 1433 ** 1434 ** to run without a statement journal if there are no indexes on the 1435 ** table. 1436 */ 1437 Trigger *pTrigger = 0; 1438 if( db->flags&SQLITE_RecTriggers ){ 1439 pTrigger = sqlite3TriggersExist(pParse, pTab, TK_DELETE, 0, 0); 1440 } 1441 if( pTrigger || sqlite3FkRequired(pParse, pTab, 0, 0) ){ 1442 sqlite3MultiWrite(pParse); 1443 sqlite3GenerateRowDelete(pParse, pTab, pTrigger, iDataCur, iIdxCur, 1444 regNewData, 1, 0, OE_Replace, 1, -1); 1445 }else{ 1446 #ifdef SQLITE_ENABLE_PREUPDATE_HOOK 1447 if( HasRowid(pTab) ){ 1448 /* This OP_Delete opcode fires the pre-update-hook only. It does 1449 ** not modify the b-tree. It is more efficient to let the coming 1450 ** OP_Insert replace the existing entry than it is to delete the 1451 ** existing entry and then insert a new one. */ 1452 sqlite3VdbeAddOp2(v, OP_Delete, iDataCur, OPFLAG_ISNOOP); 1453 sqlite3VdbeAppendP4(v, pTab, P4_TABLE); 1454 } 1455 #endif /* SQLITE_ENABLE_PREUPDATE_HOOK */ 1456 if( pTab->pIndex ){ 1457 sqlite3MultiWrite(pParse); 1458 sqlite3GenerateRowIndexDelete(pParse, pTab, iDataCur, iIdxCur,0,-1); 1459 } 1460 } 1461 seenReplace = 1; 1462 break; 1463 } 1464 case OE_Ignore: { 1465 /*assert( seenReplace==0 );*/ 1466 sqlite3VdbeGoto(v, ignoreDest); 1467 break; 1468 } 1469 } 1470 sqlite3VdbeResolveLabel(v, addrRowidOk); 1471 if( ipkTop ){ 1472 ipkBottom = sqlite3VdbeAddOp0(v, OP_Goto); 1473 sqlite3VdbeJumpHere(v, ipkTop); 1474 } 1475 } 1476 1477 /* Test all UNIQUE constraints by creating entries for each UNIQUE 1478 ** index and making sure that duplicate entries do not already exist. 1479 ** Compute the revised record entries for indices as we go. 1480 ** 1481 ** This loop also handles the case of the PRIMARY KEY index for a 1482 ** WITHOUT ROWID table. 1483 */ 1484 for(ix=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, ix++){ 1485 int regIdx; /* Range of registers hold conent for pIdx */ 1486 int regR; /* Range of registers holding conflicting PK */ 1487 int iThisCur; /* Cursor for this UNIQUE index */ 1488 int addrUniqueOk; /* Jump here if the UNIQUE constraint is satisfied */ 1489 1490 if( aRegIdx[ix]==0 ) continue; /* Skip indices that do not change */ 1491 if( bAffinityDone==0 ){ 1492 sqlite3TableAffinity(v, pTab, regNewData+1); 1493 bAffinityDone = 1; 1494 } 1495 iThisCur = iIdxCur+ix; 1496 addrUniqueOk = sqlite3VdbeMakeLabel(v); 1497 1498 /* Skip partial indices for which the WHERE clause is not true */ 1499 if( pIdx->pPartIdxWhere ){ 1500 sqlite3VdbeAddOp2(v, OP_Null, 0, aRegIdx[ix]); 1501 pParse->iSelfTab = -(regNewData+1); 1502 sqlite3ExprIfFalseDup(pParse, pIdx->pPartIdxWhere, addrUniqueOk, 1503 SQLITE_JUMPIFNULL); 1504 pParse->iSelfTab = 0; 1505 } 1506 1507 /* Create a record for this index entry as it should appear after 1508 ** the insert or update. Store that record in the aRegIdx[ix] register 1509 */ 1510 regIdx = aRegIdx[ix]+1; 1511 for(i=0; i<pIdx->nColumn; i++){ 1512 int iField = pIdx->aiColumn[i]; 1513 int x; 1514 if( iField==XN_EXPR ){ 1515 pParse->iSelfTab = -(regNewData+1); 1516 sqlite3ExprCodeCopy(pParse, pIdx->aColExpr->a[i].pExpr, regIdx+i); 1517 pParse->iSelfTab = 0; 1518 VdbeComment((v, "%s column %d", pIdx->zName, i)); 1519 }else{ 1520 if( iField==XN_ROWID || iField==pTab->iPKey ){ 1521 x = regNewData; 1522 }else{ 1523 x = iField + regNewData + 1; 1524 } 1525 sqlite3VdbeAddOp2(v, iField<0 ? OP_IntCopy : OP_SCopy, x, regIdx+i); 1526 VdbeComment((v, "%s", iField<0 ? "rowid" : pTab->aCol[iField].zName)); 1527 } 1528 } 1529 sqlite3VdbeAddOp3(v, OP_MakeRecord, regIdx, pIdx->nColumn, aRegIdx[ix]); 1530 VdbeComment((v, "for %s", pIdx->zName)); 1531 #ifdef SQLITE_ENABLE_NULL_TRIM 1532 if( pIdx->idxType==2 ) sqlite3SetMakeRecordP5(v, pIdx->pTable); 1533 #endif 1534 1535 /* In an UPDATE operation, if this index is the PRIMARY KEY index 1536 ** of a WITHOUT ROWID table and there has been no change the 1537 ** primary key, then no collision is possible. The collision detection 1538 ** logic below can all be skipped. */ 1539 if( isUpdate && pPk==pIdx && pkChng==0 ){ 1540 sqlite3VdbeResolveLabel(v, addrUniqueOk); 1541 continue; 1542 } 1543 1544 /* Find out what action to take in case there is a uniqueness conflict */ 1545 onError = pIdx->onError; 1546 if( onError==OE_None ){ 1547 sqlite3VdbeResolveLabel(v, addrUniqueOk); 1548 continue; /* pIdx is not a UNIQUE index */ 1549 } 1550 if( overrideError!=OE_Default ){ 1551 onError = overrideError; 1552 }else if( onError==OE_Default ){ 1553 onError = OE_Abort; 1554 } 1555 1556 /* Collision detection may be omitted if all of the following are true: 1557 ** (1) The conflict resolution algorithm is REPLACE 1558 ** (2) The table is a WITHOUT ROWID table 1559 ** (3) There are no secondary indexes on the table 1560 ** (4) No delete triggers need to be fired if there is a conflict 1561 ** (5) No FK constraint counters need to be updated if a conflict occurs. 1562 */ 1563 if( (ix==0 && pIdx->pNext==0) /* Condition 3 */ 1564 && pPk==pIdx /* Condition 2 */ 1565 && onError==OE_Replace /* Condition 1 */ 1566 && ( 0==(db->flags&SQLITE_RecTriggers) || /* Condition 4 */ 1567 0==sqlite3TriggersExist(pParse, pTab, TK_DELETE, 0, 0)) 1568 && ( 0==(db->flags&SQLITE_ForeignKeys) || /* Condition 5 */ 1569 (0==pTab->pFKey && 0==sqlite3FkReferences(pTab))) 1570 ){ 1571 sqlite3VdbeResolveLabel(v, addrUniqueOk); 1572 continue; 1573 } 1574 1575 /* Check to see if the new index entry will be unique */ 1576 sqlite3VdbeAddOp4Int(v, OP_NoConflict, iThisCur, addrUniqueOk, 1577 regIdx, pIdx->nKeyCol); VdbeCoverage(v); 1578 1579 /* Generate code to handle collisions */ 1580 regR = (pIdx==pPk) ? regIdx : sqlite3GetTempRange(pParse, nPkField); 1581 if( isUpdate || onError==OE_Replace ){ 1582 if( HasRowid(pTab) ){ 1583 sqlite3VdbeAddOp2(v, OP_IdxRowid, iThisCur, regR); 1584 /* Conflict only if the rowid of the existing index entry 1585 ** is different from old-rowid */ 1586 if( isUpdate ){ 1587 sqlite3VdbeAddOp3(v, OP_Eq, regR, addrUniqueOk, regOldData); 1588 sqlite3VdbeChangeP5(v, SQLITE_NOTNULL); 1589 VdbeCoverage(v); 1590 } 1591 }else{ 1592 int x; 1593 /* Extract the PRIMARY KEY from the end of the index entry and 1594 ** store it in registers regR..regR+nPk-1 */ 1595 if( pIdx!=pPk ){ 1596 for(i=0; i<pPk->nKeyCol; i++){ 1597 assert( pPk->aiColumn[i]>=0 ); 1598 x = sqlite3ColumnOfIndex(pIdx, pPk->aiColumn[i]); 1599 sqlite3VdbeAddOp3(v, OP_Column, iThisCur, x, regR+i); 1600 VdbeComment((v, "%s.%s", pTab->zName, 1601 pTab->aCol[pPk->aiColumn[i]].zName)); 1602 } 1603 } 1604 if( isUpdate ){ 1605 /* If currently processing the PRIMARY KEY of a WITHOUT ROWID 1606 ** table, only conflict if the new PRIMARY KEY values are actually 1607 ** different from the old. 1608 ** 1609 ** For a UNIQUE index, only conflict if the PRIMARY KEY values 1610 ** of the matched index row are different from the original PRIMARY 1611 ** KEY values of this row before the update. */ 1612 int addrJump = sqlite3VdbeCurrentAddr(v)+pPk->nKeyCol; 1613 int op = OP_Ne; 1614 int regCmp = (IsPrimaryKeyIndex(pIdx) ? regIdx : regR); 1615 1616 for(i=0; i<pPk->nKeyCol; i++){ 1617 char *p4 = (char*)sqlite3LocateCollSeq(pParse, pPk->azColl[i]); 1618 x = pPk->aiColumn[i]; 1619 assert( x>=0 ); 1620 if( i==(pPk->nKeyCol-1) ){ 1621 addrJump = addrUniqueOk; 1622 op = OP_Eq; 1623 } 1624 sqlite3VdbeAddOp4(v, op, 1625 regOldData+1+x, addrJump, regCmp+i, p4, P4_COLLSEQ 1626 ); 1627 sqlite3VdbeChangeP5(v, SQLITE_NOTNULL); 1628 VdbeCoverageIf(v, op==OP_Eq); 1629 VdbeCoverageIf(v, op==OP_Ne); 1630 } 1631 } 1632 } 1633 } 1634 1635 /* Generate code that executes if the new index entry is not unique */ 1636 assert( onError==OE_Rollback || onError==OE_Abort || onError==OE_Fail 1637 || onError==OE_Ignore || onError==OE_Replace ); 1638 switch( onError ){ 1639 case OE_Rollback: 1640 case OE_Abort: 1641 case OE_Fail: { 1642 sqlite3UniqueConstraint(pParse, onError, pIdx); 1643 break; 1644 } 1645 case OE_Ignore: { 1646 sqlite3VdbeGoto(v, ignoreDest); 1647 break; 1648 } 1649 default: { 1650 Trigger *pTrigger = 0; 1651 assert( onError==OE_Replace ); 1652 sqlite3MultiWrite(pParse); 1653 if( db->flags&SQLITE_RecTriggers ){ 1654 pTrigger = sqlite3TriggersExist(pParse, pTab, TK_DELETE, 0, 0); 1655 } 1656 sqlite3GenerateRowDelete(pParse, pTab, pTrigger, iDataCur, iIdxCur, 1657 regR, nPkField, 0, OE_Replace, 1658 (pIdx==pPk ? ONEPASS_SINGLE : ONEPASS_OFF), iThisCur); 1659 seenReplace = 1; 1660 break; 1661 } 1662 } 1663 sqlite3VdbeResolveLabel(v, addrUniqueOk); 1664 if( regR!=regIdx ) sqlite3ReleaseTempRange(pParse, regR, nPkField); 1665 } 1666 if( ipkTop ){ 1667 sqlite3VdbeGoto(v, ipkTop+1); 1668 sqlite3VdbeJumpHere(v, ipkBottom); 1669 } 1670 1671 *pbMayReplace = seenReplace; 1672 VdbeModuleComment((v, "END: GenCnstCks(%d)", seenReplace)); 1673 } 1674 1675 #ifdef SQLITE_ENABLE_NULL_TRIM 1676 /* 1677 ** Change the P5 operand on the last opcode (which should be an OP_MakeRecord) 1678 ** to be the number of columns in table pTab that must not be NULL-trimmed. 1679 ** 1680 ** Or if no columns of pTab may be NULL-trimmed, leave P5 at zero. 1681 */ 1682 void sqlite3SetMakeRecordP5(Vdbe *v, Table *pTab){ 1683 u16 i; 1684 1685 /* Records with omitted columns are only allowed for schema format 1686 ** version 2 and later (SQLite version 3.1.4, 2005-02-20). */ 1687 if( pTab->pSchema->file_format<2 ) return; 1688 1689 for(i=pTab->nCol-1; i>0; i--){ 1690 if( pTab->aCol[i].pDflt!=0 ) break; 1691 if( pTab->aCol[i].colFlags & COLFLAG_PRIMKEY ) break; 1692 } 1693 sqlite3VdbeChangeP5(v, i+1); 1694 } 1695 #endif 1696 1697 /* 1698 ** This routine generates code to finish the INSERT or UPDATE operation 1699 ** that was started by a prior call to sqlite3GenerateConstraintChecks. 1700 ** A consecutive range of registers starting at regNewData contains the 1701 ** rowid and the content to be inserted. 1702 ** 1703 ** The arguments to this routine should be the same as the first six 1704 ** arguments to sqlite3GenerateConstraintChecks. 1705 */ 1706 void sqlite3CompleteInsertion( 1707 Parse *pParse, /* The parser context */ 1708 Table *pTab, /* the table into which we are inserting */ 1709 int iDataCur, /* Cursor of the canonical data source */ 1710 int iIdxCur, /* First index cursor */ 1711 int regNewData, /* Range of content */ 1712 int *aRegIdx, /* Register used by each index. 0 for unused indices */ 1713 int update_flags, /* True for UPDATE, False for INSERT */ 1714 int appendBias, /* True if this is likely to be an append */ 1715 int useSeekResult /* True to set the USESEEKRESULT flag on OP_[Idx]Insert */ 1716 ){ 1717 Vdbe *v; /* Prepared statements under construction */ 1718 Index *pIdx; /* An index being inserted or updated */ 1719 u8 pik_flags; /* flag values passed to the btree insert */ 1720 int regData; /* Content registers (after the rowid) */ 1721 int regRec; /* Register holding assembled record for the table */ 1722 int i; /* Loop counter */ 1723 u8 bAffinityDone = 0; /* True if OP_Affinity has been run already */ 1724 1725 assert( update_flags==0 1726 || update_flags==OPFLAG_ISUPDATE 1727 || update_flags==(OPFLAG_ISUPDATE|OPFLAG_SAVEPOSITION) 1728 ); 1729 1730 v = sqlite3GetVdbe(pParse); 1731 assert( v!=0 ); 1732 assert( pTab->pSelect==0 ); /* This table is not a VIEW */ 1733 for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){ 1734 if( aRegIdx[i]==0 ) continue; 1735 bAffinityDone = 1; 1736 if( pIdx->pPartIdxWhere ){ 1737 sqlite3VdbeAddOp2(v, OP_IsNull, aRegIdx[i], sqlite3VdbeCurrentAddr(v)+2); 1738 VdbeCoverage(v); 1739 } 1740 pik_flags = (useSeekResult ? OPFLAG_USESEEKRESULT : 0); 1741 if( IsPrimaryKeyIndex(pIdx) && !HasRowid(pTab) ){ 1742 assert( pParse->nested==0 ); 1743 pik_flags |= OPFLAG_NCHANGE; 1744 pik_flags |= (update_flags & OPFLAG_SAVEPOSITION); 1745 #ifdef SQLITE_ENABLE_PREUPDATE_HOOK 1746 if( update_flags==0 ){ 1747 sqlite3VdbeAddOp4(v, OP_InsertInt, 1748 iIdxCur+i, aRegIdx[i], 0, (char*)pTab, P4_TABLE 1749 ); 1750 sqlite3VdbeChangeP5(v, OPFLAG_ISNOOP); 1751 } 1752 #endif 1753 } 1754 sqlite3VdbeAddOp4Int(v, OP_IdxInsert, iIdxCur+i, aRegIdx[i], 1755 aRegIdx[i]+1, 1756 pIdx->uniqNotNull ? pIdx->nKeyCol: pIdx->nColumn); 1757 sqlite3VdbeChangeP5(v, pik_flags); 1758 } 1759 if( !HasRowid(pTab) ) return; 1760 regData = regNewData + 1; 1761 regRec = sqlite3GetTempReg(pParse); 1762 sqlite3VdbeAddOp3(v, OP_MakeRecord, regData, pTab->nCol, regRec); 1763 sqlite3SetMakeRecordP5(v, pTab); 1764 if( !bAffinityDone ){ 1765 sqlite3TableAffinity(v, pTab, 0); 1766 sqlite3ExprCacheAffinityChange(pParse, regData, pTab->nCol); 1767 } 1768 if( pParse->nested ){ 1769 pik_flags = 0; 1770 }else{ 1771 pik_flags = OPFLAG_NCHANGE; 1772 pik_flags |= (update_flags?update_flags:OPFLAG_LASTROWID); 1773 } 1774 if( appendBias ){ 1775 pik_flags |= OPFLAG_APPEND; 1776 } 1777 if( useSeekResult ){ 1778 pik_flags |= OPFLAG_USESEEKRESULT; 1779 } 1780 sqlite3VdbeAddOp3(v, OP_Insert, iDataCur, regRec, regNewData); 1781 if( !pParse->nested ){ 1782 sqlite3VdbeAppendP4(v, pTab, P4_TABLE); 1783 } 1784 sqlite3VdbeChangeP5(v, pik_flags); 1785 } 1786 1787 /* 1788 ** Allocate cursors for the pTab table and all its indices and generate 1789 ** code to open and initialized those cursors. 1790 ** 1791 ** The cursor for the object that contains the complete data (normally 1792 ** the table itself, but the PRIMARY KEY index in the case of a WITHOUT 1793 ** ROWID table) is returned in *piDataCur. The first index cursor is 1794 ** returned in *piIdxCur. The number of indices is returned. 1795 ** 1796 ** Use iBase as the first cursor (either the *piDataCur for rowid tables 1797 ** or the first index for WITHOUT ROWID tables) if it is non-negative. 1798 ** If iBase is negative, then allocate the next available cursor. 1799 ** 1800 ** For a rowid table, *piDataCur will be exactly one less than *piIdxCur. 1801 ** For a WITHOUT ROWID table, *piDataCur will be somewhere in the range 1802 ** of *piIdxCurs, depending on where the PRIMARY KEY index appears on the 1803 ** pTab->pIndex list. 1804 ** 1805 ** If pTab is a virtual table, then this routine is a no-op and the 1806 ** *piDataCur and *piIdxCur values are left uninitialized. 1807 */ 1808 int sqlite3OpenTableAndIndices( 1809 Parse *pParse, /* Parsing context */ 1810 Table *pTab, /* Table to be opened */ 1811 int op, /* OP_OpenRead or OP_OpenWrite */ 1812 u8 p5, /* P5 value for OP_Open* opcodes (except on WITHOUT ROWID) */ 1813 int iBase, /* Use this for the table cursor, if there is one */ 1814 u8 *aToOpen, /* If not NULL: boolean for each table and index */ 1815 int *piDataCur, /* Write the database source cursor number here */ 1816 int *piIdxCur /* Write the first index cursor number here */ 1817 ){ 1818 int i; 1819 int iDb; 1820 int iDataCur; 1821 Index *pIdx; 1822 Vdbe *v; 1823 1824 assert( op==OP_OpenRead || op==OP_OpenWrite ); 1825 assert( op==OP_OpenWrite || p5==0 ); 1826 if( IsVirtual(pTab) ){ 1827 /* This routine is a no-op for virtual tables. Leave the output 1828 ** variables *piDataCur and *piIdxCur uninitialized so that valgrind 1829 ** can detect if they are used by mistake in the caller. */ 1830 return 0; 1831 } 1832 iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema); 1833 v = sqlite3GetVdbe(pParse); 1834 assert( v!=0 ); 1835 if( iBase<0 ) iBase = pParse->nTab; 1836 iDataCur = iBase++; 1837 if( piDataCur ) *piDataCur = iDataCur; 1838 if( HasRowid(pTab) && (aToOpen==0 || aToOpen[0]) ){ 1839 sqlite3OpenTable(pParse, iDataCur, iDb, pTab, op); 1840 }else{ 1841 sqlite3TableLock(pParse, iDb, pTab->tnum, op==OP_OpenWrite, pTab->zName); 1842 } 1843 if( piIdxCur ) *piIdxCur = iBase; 1844 for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){ 1845 int iIdxCur = iBase++; 1846 assert( pIdx->pSchema==pTab->pSchema ); 1847 if( IsPrimaryKeyIndex(pIdx) && !HasRowid(pTab) ){ 1848 if( piDataCur ) *piDataCur = iIdxCur; 1849 p5 = 0; 1850 } 1851 if( aToOpen==0 || aToOpen[i+1] ){ 1852 sqlite3VdbeAddOp3(v, op, iIdxCur, pIdx->tnum, iDb); 1853 sqlite3VdbeSetP4KeyInfo(pParse, pIdx); 1854 sqlite3VdbeChangeP5(v, p5); 1855 VdbeComment((v, "%s", pIdx->zName)); 1856 } 1857 } 1858 if( iBase>pParse->nTab ) pParse->nTab = iBase; 1859 return i; 1860 } 1861 1862 1863 #ifdef SQLITE_TEST 1864 /* 1865 ** The following global variable is incremented whenever the 1866 ** transfer optimization is used. This is used for testing 1867 ** purposes only - to make sure the transfer optimization really 1868 ** is happening when it is supposed to. 1869 */ 1870 int sqlite3_xferopt_count; 1871 #endif /* SQLITE_TEST */ 1872 1873 1874 #ifndef SQLITE_OMIT_XFER_OPT 1875 /* 1876 ** Check to see if index pSrc is compatible as a source of data 1877 ** for index pDest in an insert transfer optimization. The rules 1878 ** for a compatible index: 1879 ** 1880 ** * The index is over the same set of columns 1881 ** * The same DESC and ASC markings occurs on all columns 1882 ** * The same onError processing (OE_Abort, OE_Ignore, etc) 1883 ** * The same collating sequence on each column 1884 ** * The index has the exact same WHERE clause 1885 */ 1886 static int xferCompatibleIndex(Index *pDest, Index *pSrc){ 1887 int i; 1888 assert( pDest && pSrc ); 1889 assert( pDest->pTable!=pSrc->pTable ); 1890 if( pDest->nKeyCol!=pSrc->nKeyCol ){ 1891 return 0; /* Different number of columns */ 1892 } 1893 if( pDest->onError!=pSrc->onError ){ 1894 return 0; /* Different conflict resolution strategies */ 1895 } 1896 for(i=0; i<pSrc->nKeyCol; i++){ 1897 if( pSrc->aiColumn[i]!=pDest->aiColumn[i] ){ 1898 return 0; /* Different columns indexed */ 1899 } 1900 if( pSrc->aiColumn[i]==XN_EXPR ){ 1901 assert( pSrc->aColExpr!=0 && pDest->aColExpr!=0 ); 1902 if( sqlite3ExprCompare(0, pSrc->aColExpr->a[i].pExpr, 1903 pDest->aColExpr->a[i].pExpr, -1)!=0 ){ 1904 return 0; /* Different expressions in the index */ 1905 } 1906 } 1907 if( pSrc->aSortOrder[i]!=pDest->aSortOrder[i] ){ 1908 return 0; /* Different sort orders */ 1909 } 1910 if( sqlite3_stricmp(pSrc->azColl[i],pDest->azColl[i])!=0 ){ 1911 return 0; /* Different collating sequences */ 1912 } 1913 } 1914 if( sqlite3ExprCompare(0, pSrc->pPartIdxWhere, pDest->pPartIdxWhere, -1) ){ 1915 return 0; /* Different WHERE clauses */ 1916 } 1917 1918 /* If no test above fails then the indices must be compatible */ 1919 return 1; 1920 } 1921 1922 /* 1923 ** Attempt the transfer optimization on INSERTs of the form 1924 ** 1925 ** INSERT INTO tab1 SELECT * FROM tab2; 1926 ** 1927 ** The xfer optimization transfers raw records from tab2 over to tab1. 1928 ** Columns are not decoded and reassembled, which greatly improves 1929 ** performance. Raw index records are transferred in the same way. 1930 ** 1931 ** The xfer optimization is only attempted if tab1 and tab2 are compatible. 1932 ** There are lots of rules for determining compatibility - see comments 1933 ** embedded in the code for details. 1934 ** 1935 ** This routine returns TRUE if the optimization is guaranteed to be used. 1936 ** Sometimes the xfer optimization will only work if the destination table 1937 ** is empty - a factor that can only be determined at run-time. In that 1938 ** case, this routine generates code for the xfer optimization but also 1939 ** does a test to see if the destination table is empty and jumps over the 1940 ** xfer optimization code if the test fails. In that case, this routine 1941 ** returns FALSE so that the caller will know to go ahead and generate 1942 ** an unoptimized transfer. This routine also returns FALSE if there 1943 ** is no chance that the xfer optimization can be applied. 1944 ** 1945 ** This optimization is particularly useful at making VACUUM run faster. 1946 */ 1947 static int xferOptimization( 1948 Parse *pParse, /* Parser context */ 1949 Table *pDest, /* The table we are inserting into */ 1950 Select *pSelect, /* A SELECT statement to use as the data source */ 1951 int onError, /* How to handle constraint errors */ 1952 int iDbDest /* The database of pDest */ 1953 ){ 1954 sqlite3 *db = pParse->db; 1955 ExprList *pEList; /* The result set of the SELECT */ 1956 Table *pSrc; /* The table in the FROM clause of SELECT */ 1957 Index *pSrcIdx, *pDestIdx; /* Source and destination indices */ 1958 struct SrcList_item *pItem; /* An element of pSelect->pSrc */ 1959 int i; /* Loop counter */ 1960 int iDbSrc; /* The database of pSrc */ 1961 int iSrc, iDest; /* Cursors from source and destination */ 1962 int addr1, addr2; /* Loop addresses */ 1963 int emptyDestTest = 0; /* Address of test for empty pDest */ 1964 int emptySrcTest = 0; /* Address of test for empty pSrc */ 1965 Vdbe *v; /* The VDBE we are building */ 1966 int regAutoinc; /* Memory register used by AUTOINC */ 1967 int destHasUniqueIdx = 0; /* True if pDest has a UNIQUE index */ 1968 int regData, regRowid; /* Registers holding data and rowid */ 1969 1970 if( pSelect==0 ){ 1971 return 0; /* Must be of the form INSERT INTO ... SELECT ... */ 1972 } 1973 if( pParse->pWith || pSelect->pWith ){ 1974 /* Do not attempt to process this query if there are an WITH clauses 1975 ** attached to it. Proceeding may generate a false "no such table: xxx" 1976 ** error if pSelect reads from a CTE named "xxx". */ 1977 return 0; 1978 } 1979 if( sqlite3TriggerList(pParse, pDest) ){ 1980 return 0; /* tab1 must not have triggers */ 1981 } 1982 #ifndef SQLITE_OMIT_VIRTUALTABLE 1983 if( IsVirtual(pDest) ){ 1984 return 0; /* tab1 must not be a virtual table */ 1985 } 1986 #endif 1987 if( onError==OE_Default ){ 1988 if( pDest->iPKey>=0 ) onError = pDest->keyConf; 1989 if( onError==OE_Default ) onError = OE_Abort; 1990 } 1991 assert(pSelect->pSrc); /* allocated even if there is no FROM clause */ 1992 if( pSelect->pSrc->nSrc!=1 ){ 1993 return 0; /* FROM clause must have exactly one term */ 1994 } 1995 if( pSelect->pSrc->a[0].pSelect ){ 1996 return 0; /* FROM clause cannot contain a subquery */ 1997 } 1998 if( pSelect->pWhere ){ 1999 return 0; /* SELECT may not have a WHERE clause */ 2000 } 2001 if( pSelect->pOrderBy ){ 2002 return 0; /* SELECT may not have an ORDER BY clause */ 2003 } 2004 /* Do not need to test for a HAVING clause. If HAVING is present but 2005 ** there is no ORDER BY, we will get an error. */ 2006 if( pSelect->pGroupBy ){ 2007 return 0; /* SELECT may not have a GROUP BY clause */ 2008 } 2009 if( pSelect->pLimit ){ 2010 return 0; /* SELECT may not have a LIMIT clause */ 2011 } 2012 assert( pSelect->pOffset==0 ); /* Must be so if pLimit==0 */ 2013 if( pSelect->pPrior ){ 2014 return 0; /* SELECT may not be a compound query */ 2015 } 2016 if( pSelect->selFlags & SF_Distinct ){ 2017 return 0; /* SELECT may not be DISTINCT */ 2018 } 2019 pEList = pSelect->pEList; 2020 assert( pEList!=0 ); 2021 if( pEList->nExpr!=1 ){ 2022 return 0; /* The result set must have exactly one column */ 2023 } 2024 assert( pEList->a[0].pExpr ); 2025 if( pEList->a[0].pExpr->op!=TK_ASTERISK ){ 2026 return 0; /* The result set must be the special operator "*" */ 2027 } 2028 2029 /* At this point we have established that the statement is of the 2030 ** correct syntactic form to participate in this optimization. Now 2031 ** we have to check the semantics. 2032 */ 2033 pItem = pSelect->pSrc->a; 2034 pSrc = sqlite3LocateTableItem(pParse, 0, pItem); 2035 if( pSrc==0 ){ 2036 return 0; /* FROM clause does not contain a real table */ 2037 } 2038 if( pSrc==pDest ){ 2039 return 0; /* tab1 and tab2 may not be the same table */ 2040 } 2041 if( HasRowid(pDest)!=HasRowid(pSrc) ){ 2042 return 0; /* source and destination must both be WITHOUT ROWID or not */ 2043 } 2044 #ifndef SQLITE_OMIT_VIRTUALTABLE 2045 if( IsVirtual(pSrc) ){ 2046 return 0; /* tab2 must not be a virtual table */ 2047 } 2048 #endif 2049 if( pSrc->pSelect ){ 2050 return 0; /* tab2 may not be a view */ 2051 } 2052 if( pDest->nCol!=pSrc->nCol ){ 2053 return 0; /* Number of columns must be the same in tab1 and tab2 */ 2054 } 2055 if( pDest->iPKey!=pSrc->iPKey ){ 2056 return 0; /* Both tables must have the same INTEGER PRIMARY KEY */ 2057 } 2058 for(i=0; i<pDest->nCol; i++){ 2059 Column *pDestCol = &pDest->aCol[i]; 2060 Column *pSrcCol = &pSrc->aCol[i]; 2061 #ifdef SQLITE_ENABLE_HIDDEN_COLUMNS 2062 if( (db->mDbFlags & DBFLAG_Vacuum)==0 2063 && (pDestCol->colFlags | pSrcCol->colFlags) & COLFLAG_HIDDEN 2064 ){ 2065 return 0; /* Neither table may have __hidden__ columns */ 2066 } 2067 #endif 2068 if( pDestCol->affinity!=pSrcCol->affinity ){ 2069 return 0; /* Affinity must be the same on all columns */ 2070 } 2071 if( sqlite3_stricmp(pDestCol->zColl, pSrcCol->zColl)!=0 ){ 2072 return 0; /* Collating sequence must be the same on all columns */ 2073 } 2074 if( pDestCol->notNull && !pSrcCol->notNull ){ 2075 return 0; /* tab2 must be NOT NULL if tab1 is */ 2076 } 2077 /* Default values for second and subsequent columns need to match. */ 2078 if( i>0 ){ 2079 assert( pDestCol->pDflt==0 || pDestCol->pDflt->op==TK_SPAN ); 2080 assert( pSrcCol->pDflt==0 || pSrcCol->pDflt->op==TK_SPAN ); 2081 if( (pDestCol->pDflt==0)!=(pSrcCol->pDflt==0) 2082 || (pDestCol->pDflt && strcmp(pDestCol->pDflt->u.zToken, 2083 pSrcCol->pDflt->u.zToken)!=0) 2084 ){ 2085 return 0; /* Default values must be the same for all columns */ 2086 } 2087 } 2088 } 2089 for(pDestIdx=pDest->pIndex; pDestIdx; pDestIdx=pDestIdx->pNext){ 2090 if( IsUniqueIndex(pDestIdx) ){ 2091 destHasUniqueIdx = 1; 2092 } 2093 for(pSrcIdx=pSrc->pIndex; pSrcIdx; pSrcIdx=pSrcIdx->pNext){ 2094 if( xferCompatibleIndex(pDestIdx, pSrcIdx) ) break; 2095 } 2096 if( pSrcIdx==0 ){ 2097 return 0; /* pDestIdx has no corresponding index in pSrc */ 2098 } 2099 } 2100 #ifndef SQLITE_OMIT_CHECK 2101 if( pDest->pCheck && sqlite3ExprListCompare(pSrc->pCheck,pDest->pCheck,-1) ){ 2102 return 0; /* Tables have different CHECK constraints. Ticket #2252 */ 2103 } 2104 #endif 2105 #ifndef SQLITE_OMIT_FOREIGN_KEY 2106 /* Disallow the transfer optimization if the destination table constains 2107 ** any foreign key constraints. This is more restrictive than necessary. 2108 ** But the main beneficiary of the transfer optimization is the VACUUM 2109 ** command, and the VACUUM command disables foreign key constraints. So 2110 ** the extra complication to make this rule less restrictive is probably 2111 ** not worth the effort. Ticket [6284df89debdfa61db8073e062908af0c9b6118e] 2112 */ 2113 if( (db->flags & SQLITE_ForeignKeys)!=0 && pDest->pFKey!=0 ){ 2114 return 0; 2115 } 2116 #endif 2117 if( (db->flags & SQLITE_CountRows)!=0 ){ 2118 return 0; /* xfer opt does not play well with PRAGMA count_changes */ 2119 } 2120 2121 /* If we get this far, it means that the xfer optimization is at 2122 ** least a possibility, though it might only work if the destination 2123 ** table (tab1) is initially empty. 2124 */ 2125 #ifdef SQLITE_TEST 2126 sqlite3_xferopt_count++; 2127 #endif 2128 iDbSrc = sqlite3SchemaToIndex(db, pSrc->pSchema); 2129 v = sqlite3GetVdbe(pParse); 2130 sqlite3CodeVerifySchema(pParse, iDbSrc); 2131 iSrc = pParse->nTab++; 2132 iDest = pParse->nTab++; 2133 regAutoinc = autoIncBegin(pParse, iDbDest, pDest); 2134 regData = sqlite3GetTempReg(pParse); 2135 regRowid = sqlite3GetTempReg(pParse); 2136 sqlite3OpenTable(pParse, iDest, iDbDest, pDest, OP_OpenWrite); 2137 assert( HasRowid(pDest) || destHasUniqueIdx ); 2138 if( (db->mDbFlags & DBFLAG_Vacuum)==0 && ( 2139 (pDest->iPKey<0 && pDest->pIndex!=0) /* (1) */ 2140 || destHasUniqueIdx /* (2) */ 2141 || (onError!=OE_Abort && onError!=OE_Rollback) /* (3) */ 2142 )){ 2143 /* In some circumstances, we are able to run the xfer optimization 2144 ** only if the destination table is initially empty. Unless the 2145 ** DBFLAG_Vacuum flag is set, this block generates code to make 2146 ** that determination. If DBFLAG_Vacuum is set, then the destination 2147 ** table is always empty. 2148 ** 2149 ** Conditions under which the destination must be empty: 2150 ** 2151 ** (1) There is no INTEGER PRIMARY KEY but there are indices. 2152 ** (If the destination is not initially empty, the rowid fields 2153 ** of index entries might need to change.) 2154 ** 2155 ** (2) The destination has a unique index. (The xfer optimization 2156 ** is unable to test uniqueness.) 2157 ** 2158 ** (3) onError is something other than OE_Abort and OE_Rollback. 2159 */ 2160 addr1 = sqlite3VdbeAddOp2(v, OP_Rewind, iDest, 0); VdbeCoverage(v); 2161 emptyDestTest = sqlite3VdbeAddOp0(v, OP_Goto); 2162 sqlite3VdbeJumpHere(v, addr1); 2163 } 2164 if( HasRowid(pSrc) ){ 2165 u8 insFlags; 2166 sqlite3OpenTable(pParse, iSrc, iDbSrc, pSrc, OP_OpenRead); 2167 emptySrcTest = sqlite3VdbeAddOp2(v, OP_Rewind, iSrc, 0); VdbeCoverage(v); 2168 if( pDest->iPKey>=0 ){ 2169 addr1 = sqlite3VdbeAddOp2(v, OP_Rowid, iSrc, regRowid); 2170 addr2 = sqlite3VdbeAddOp3(v, OP_NotExists, iDest, 0, regRowid); 2171 VdbeCoverage(v); 2172 sqlite3RowidConstraint(pParse, onError, pDest); 2173 sqlite3VdbeJumpHere(v, addr2); 2174 autoIncStep(pParse, regAutoinc, regRowid); 2175 }else if( pDest->pIndex==0 ){ 2176 addr1 = sqlite3VdbeAddOp2(v, OP_NewRowid, iDest, regRowid); 2177 }else{ 2178 addr1 = sqlite3VdbeAddOp2(v, OP_Rowid, iSrc, regRowid); 2179 assert( (pDest->tabFlags & TF_Autoincrement)==0 ); 2180 } 2181 sqlite3VdbeAddOp3(v, OP_RowData, iSrc, regData, 1); 2182 if( db->mDbFlags & DBFLAG_Vacuum ){ 2183 sqlite3VdbeAddOp1(v, OP_SeekEnd, iDest); 2184 insFlags = OPFLAG_NCHANGE|OPFLAG_LASTROWID| 2185 OPFLAG_APPEND|OPFLAG_USESEEKRESULT; 2186 }else{ 2187 insFlags = OPFLAG_NCHANGE|OPFLAG_LASTROWID|OPFLAG_APPEND; 2188 } 2189 sqlite3VdbeAddOp4(v, OP_Insert, iDest, regData, regRowid, 2190 (char*)pDest, P4_TABLE); 2191 sqlite3VdbeChangeP5(v, insFlags); 2192 sqlite3VdbeAddOp2(v, OP_Next, iSrc, addr1); VdbeCoverage(v); 2193 sqlite3VdbeAddOp2(v, OP_Close, iSrc, 0); 2194 sqlite3VdbeAddOp2(v, OP_Close, iDest, 0); 2195 }else{ 2196 sqlite3TableLock(pParse, iDbDest, pDest->tnum, 1, pDest->zName); 2197 sqlite3TableLock(pParse, iDbSrc, pSrc->tnum, 0, pSrc->zName); 2198 } 2199 for(pDestIdx=pDest->pIndex; pDestIdx; pDestIdx=pDestIdx->pNext){ 2200 u8 idxInsFlags = 0; 2201 for(pSrcIdx=pSrc->pIndex; ALWAYS(pSrcIdx); pSrcIdx=pSrcIdx->pNext){ 2202 if( xferCompatibleIndex(pDestIdx, pSrcIdx) ) break; 2203 } 2204 assert( pSrcIdx ); 2205 sqlite3VdbeAddOp3(v, OP_OpenRead, iSrc, pSrcIdx->tnum, iDbSrc); 2206 sqlite3VdbeSetP4KeyInfo(pParse, pSrcIdx); 2207 VdbeComment((v, "%s", pSrcIdx->zName)); 2208 sqlite3VdbeAddOp3(v, OP_OpenWrite, iDest, pDestIdx->tnum, iDbDest); 2209 sqlite3VdbeSetP4KeyInfo(pParse, pDestIdx); 2210 sqlite3VdbeChangeP5(v, OPFLAG_BULKCSR); 2211 VdbeComment((v, "%s", pDestIdx->zName)); 2212 addr1 = sqlite3VdbeAddOp2(v, OP_Rewind, iSrc, 0); VdbeCoverage(v); 2213 sqlite3VdbeAddOp3(v, OP_RowData, iSrc, regData, 1); 2214 if( db->mDbFlags & DBFLAG_Vacuum ){ 2215 /* This INSERT command is part of a VACUUM operation, which guarantees 2216 ** that the destination table is empty. If all indexed columns use 2217 ** collation sequence BINARY, then it can also be assumed that the 2218 ** index will be populated by inserting keys in strictly sorted 2219 ** order. In this case, instead of seeking within the b-tree as part 2220 ** of every OP_IdxInsert opcode, an OP_SeekEnd is added before the 2221 ** OP_IdxInsert to seek to the point within the b-tree where each key 2222 ** should be inserted. This is faster. 2223 ** 2224 ** If any of the indexed columns use a collation sequence other than 2225 ** BINARY, this optimization is disabled. This is because the user 2226 ** might change the definition of a collation sequence and then run 2227 ** a VACUUM command. In that case keys may not be written in strictly 2228 ** sorted order. */ 2229 for(i=0; i<pSrcIdx->nColumn; i++){ 2230 const char *zColl = pSrcIdx->azColl[i]; 2231 if( sqlite3_stricmp(sqlite3StrBINARY, zColl) ) break; 2232 } 2233 if( i==pSrcIdx->nColumn ){ 2234 idxInsFlags = OPFLAG_USESEEKRESULT; 2235 sqlite3VdbeAddOp1(v, OP_SeekEnd, iDest); 2236 } 2237 } 2238 if( !HasRowid(pSrc) && pDestIdx->idxType==2 ){ 2239 idxInsFlags |= OPFLAG_NCHANGE; 2240 } 2241 sqlite3VdbeAddOp2(v, OP_IdxInsert, iDest, regData); 2242 sqlite3VdbeChangeP5(v, idxInsFlags|OPFLAG_APPEND); 2243 sqlite3VdbeAddOp2(v, OP_Next, iSrc, addr1+1); VdbeCoverage(v); 2244 sqlite3VdbeJumpHere(v, addr1); 2245 sqlite3VdbeAddOp2(v, OP_Close, iSrc, 0); 2246 sqlite3VdbeAddOp2(v, OP_Close, iDest, 0); 2247 } 2248 if( emptySrcTest ) sqlite3VdbeJumpHere(v, emptySrcTest); 2249 sqlite3ReleaseTempReg(pParse, regRowid); 2250 sqlite3ReleaseTempReg(pParse, regData); 2251 if( emptyDestTest ){ 2252 sqlite3AutoincrementEnd(pParse); 2253 sqlite3VdbeAddOp2(v, OP_Halt, SQLITE_OK, 0); 2254 sqlite3VdbeJumpHere(v, emptyDestTest); 2255 sqlite3VdbeAddOp2(v, OP_Close, iDest, 0); 2256 return 0; 2257 }else{ 2258 return 1; 2259 } 2260 } 2261 #endif /* SQLITE_OMIT_XFER_OPT */ 2262