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 assert( zColAff!=0 ); 150 i = sqlite3Strlen30NN(zColAff); 151 if( i ){ 152 if( iReg ){ 153 sqlite3VdbeAddOp4(v, OP_Affinity, iReg, i, 0, zColAff, i); 154 }else{ 155 sqlite3VdbeChangeP4(v, -1, zColAff, i); 156 } 157 } 158 } 159 160 /* 161 ** Return non-zero if the table pTab in database iDb or any of its indices 162 ** have been opened at any point in the VDBE program. This is used to see if 163 ** a statement of the form "INSERT INTO <iDb, pTab> SELECT ..." can 164 ** run without using a temporary table for the results of the SELECT. 165 */ 166 static int readsTable(Parse *p, int iDb, Table *pTab){ 167 Vdbe *v = sqlite3GetVdbe(p); 168 int i; 169 int iEnd = sqlite3VdbeCurrentAddr(v); 170 #ifndef SQLITE_OMIT_VIRTUALTABLE 171 VTable *pVTab = IsVirtual(pTab) ? sqlite3GetVTable(p->db, pTab) : 0; 172 #endif 173 174 for(i=1; i<iEnd; i++){ 175 VdbeOp *pOp = sqlite3VdbeGetOp(v, i); 176 assert( pOp!=0 ); 177 if( pOp->opcode==OP_OpenRead && pOp->p3==iDb ){ 178 Index *pIndex; 179 int tnum = pOp->p2; 180 if( tnum==pTab->tnum ){ 181 return 1; 182 } 183 for(pIndex=pTab->pIndex; pIndex; pIndex=pIndex->pNext){ 184 if( tnum==pIndex->tnum ){ 185 return 1; 186 } 187 } 188 } 189 #ifndef SQLITE_OMIT_VIRTUALTABLE 190 if( pOp->opcode==OP_VOpen && pOp->p4.pVtab==pVTab ){ 191 assert( pOp->p4.pVtab!=0 ); 192 assert( pOp->p4type==P4_VTAB ); 193 return 1; 194 } 195 #endif 196 } 197 return 0; 198 } 199 200 #ifndef SQLITE_OMIT_AUTOINCREMENT 201 /* 202 ** Locate or create an AutoincInfo structure associated with table pTab 203 ** which is in database iDb. Return the register number for the register 204 ** that holds the maximum rowid. Return zero if pTab is not an AUTOINCREMENT 205 ** table. (Also return zero when doing a VACUUM since we do not want to 206 ** update the AUTOINCREMENT counters during a VACUUM.) 207 ** 208 ** There is at most one AutoincInfo structure per table even if the 209 ** same table is autoincremented multiple times due to inserts within 210 ** triggers. A new AutoincInfo structure is created if this is the 211 ** first use of table pTab. On 2nd and subsequent uses, the original 212 ** AutoincInfo structure is used. 213 ** 214 ** Four consecutive registers are allocated: 215 ** 216 ** (1) The name of the pTab table. 217 ** (2) The maximum ROWID of pTab. 218 ** (3) The rowid in sqlite_sequence of pTab 219 ** (4) The original value of the max ROWID in pTab, or NULL if none 220 ** 221 ** The 2nd register is the one that is returned. That is all the 222 ** insert routine needs to know about. 223 */ 224 static int autoIncBegin( 225 Parse *pParse, /* Parsing context */ 226 int iDb, /* Index of the database holding pTab */ 227 Table *pTab /* The table we are writing to */ 228 ){ 229 int memId = 0; /* Register holding maximum rowid */ 230 assert( pParse->db->aDb[iDb].pSchema!=0 ); 231 if( (pTab->tabFlags & TF_Autoincrement)!=0 232 && (pParse->db->mDbFlags & DBFLAG_Vacuum)==0 233 ){ 234 Parse *pToplevel = sqlite3ParseToplevel(pParse); 235 AutoincInfo *pInfo; 236 Table *pSeqTab = pParse->db->aDb[iDb].pSchema->pSeqTab; 237 238 /* Verify that the sqlite_sequence table exists and is an ordinary 239 ** rowid table with exactly two columns. 240 ** Ticket d8dc2b3a58cd5dc2918a1d4acb 2018-05-23 */ 241 if( pSeqTab==0 242 || !HasRowid(pSeqTab) 243 || IsVirtual(pSeqTab) 244 || pSeqTab->nCol!=2 245 ){ 246 pParse->nErr++; 247 pParse->rc = SQLITE_CORRUPT_SEQUENCE; 248 return 0; 249 } 250 251 pInfo = pToplevel->pAinc; 252 while( pInfo && pInfo->pTab!=pTab ){ pInfo = pInfo->pNext; } 253 if( pInfo==0 ){ 254 pInfo = sqlite3DbMallocRawNN(pParse->db, sizeof(*pInfo)); 255 if( pInfo==0 ) return 0; 256 pInfo->pNext = pToplevel->pAinc; 257 pToplevel->pAinc = pInfo; 258 pInfo->pTab = pTab; 259 pInfo->iDb = iDb; 260 pToplevel->nMem++; /* Register to hold name of table */ 261 pInfo->regCtr = ++pToplevel->nMem; /* Max rowid register */ 262 pToplevel->nMem +=2; /* Rowid in sqlite_sequence + orig max val */ 263 } 264 memId = pInfo->regCtr; 265 } 266 return memId; 267 } 268 269 /* 270 ** This routine generates code that will initialize all of the 271 ** register used by the autoincrement tracker. 272 */ 273 void sqlite3AutoincrementBegin(Parse *pParse){ 274 AutoincInfo *p; /* Information about an AUTOINCREMENT */ 275 sqlite3 *db = pParse->db; /* The database connection */ 276 Db *pDb; /* Database only autoinc table */ 277 int memId; /* Register holding max rowid */ 278 Vdbe *v = pParse->pVdbe; /* VDBE under construction */ 279 280 /* This routine is never called during trigger-generation. It is 281 ** only called from the top-level */ 282 assert( pParse->pTriggerTab==0 ); 283 assert( sqlite3IsToplevel(pParse) ); 284 285 assert( v ); /* We failed long ago if this is not so */ 286 for(p = pParse->pAinc; p; p = p->pNext){ 287 static const int iLn = VDBE_OFFSET_LINENO(2); 288 static const VdbeOpList autoInc[] = { 289 /* 0 */ {OP_Null, 0, 0, 0}, 290 /* 1 */ {OP_Rewind, 0, 10, 0}, 291 /* 2 */ {OP_Column, 0, 0, 0}, 292 /* 3 */ {OP_Ne, 0, 9, 0}, 293 /* 4 */ {OP_Rowid, 0, 0, 0}, 294 /* 5 */ {OP_Column, 0, 1, 0}, 295 /* 6 */ {OP_AddImm, 0, 0, 0}, 296 /* 7 */ {OP_Copy, 0, 0, 0}, 297 /* 8 */ {OP_Goto, 0, 11, 0}, 298 /* 9 */ {OP_Next, 0, 2, 0}, 299 /* 10 */ {OP_Integer, 0, 0, 0}, 300 /* 11 */ {OP_Close, 0, 0, 0} 301 }; 302 VdbeOp *aOp; 303 pDb = &db->aDb[p->iDb]; 304 memId = p->regCtr; 305 assert( sqlite3SchemaMutexHeld(db, 0, pDb->pSchema) ); 306 sqlite3OpenTable(pParse, 0, p->iDb, pDb->pSchema->pSeqTab, OP_OpenRead); 307 sqlite3VdbeLoadString(v, memId-1, p->pTab->zName); 308 aOp = sqlite3VdbeAddOpList(v, ArraySize(autoInc), autoInc, iLn); 309 if( aOp==0 ) break; 310 aOp[0].p2 = memId; 311 aOp[0].p3 = memId+2; 312 aOp[2].p3 = memId; 313 aOp[3].p1 = memId-1; 314 aOp[3].p3 = memId; 315 aOp[3].p5 = SQLITE_JUMPIFNULL; 316 aOp[4].p2 = memId+1; 317 aOp[5].p3 = memId; 318 aOp[6].p1 = memId; 319 aOp[7].p2 = memId+2; 320 aOp[7].p1 = memId; 321 aOp[10].p2 = memId; 322 if( pParse->nTab==0 ) pParse->nTab = 1; 323 } 324 } 325 326 /* 327 ** Update the maximum rowid for an autoincrement calculation. 328 ** 329 ** This routine should be called when the regRowid register holds a 330 ** new rowid that is about to be inserted. If that new rowid is 331 ** larger than the maximum rowid in the memId memory cell, then the 332 ** memory cell is updated. 333 */ 334 static void autoIncStep(Parse *pParse, int memId, int regRowid){ 335 if( memId>0 ){ 336 sqlite3VdbeAddOp2(pParse->pVdbe, OP_MemMax, memId, regRowid); 337 } 338 } 339 340 /* 341 ** This routine generates the code needed to write autoincrement 342 ** maximum rowid values back into the sqlite_sequence register. 343 ** Every statement that might do an INSERT into an autoincrement 344 ** table (either directly or through triggers) needs to call this 345 ** routine just before the "exit" code. 346 */ 347 static SQLITE_NOINLINE void autoIncrementEnd(Parse *pParse){ 348 AutoincInfo *p; 349 Vdbe *v = pParse->pVdbe; 350 sqlite3 *db = pParse->db; 351 352 assert( v ); 353 for(p = pParse->pAinc; p; p = p->pNext){ 354 static const int iLn = VDBE_OFFSET_LINENO(2); 355 static const VdbeOpList autoIncEnd[] = { 356 /* 0 */ {OP_NotNull, 0, 2, 0}, 357 /* 1 */ {OP_NewRowid, 0, 0, 0}, 358 /* 2 */ {OP_MakeRecord, 0, 2, 0}, 359 /* 3 */ {OP_Insert, 0, 0, 0}, 360 /* 4 */ {OP_Close, 0, 0, 0} 361 }; 362 VdbeOp *aOp; 363 Db *pDb = &db->aDb[p->iDb]; 364 int iRec; 365 int memId = p->regCtr; 366 367 iRec = sqlite3GetTempReg(pParse); 368 assert( sqlite3SchemaMutexHeld(db, 0, pDb->pSchema) ); 369 sqlite3VdbeAddOp3(v, OP_Le, memId+2, sqlite3VdbeCurrentAddr(v)+7, memId); 370 VdbeCoverage(v); 371 sqlite3OpenTable(pParse, 0, p->iDb, pDb->pSchema->pSeqTab, OP_OpenWrite); 372 aOp = sqlite3VdbeAddOpList(v, ArraySize(autoIncEnd), autoIncEnd, iLn); 373 if( aOp==0 ) break; 374 aOp[0].p1 = memId+1; 375 aOp[1].p2 = memId+1; 376 aOp[2].p1 = memId-1; 377 aOp[2].p3 = iRec; 378 aOp[3].p2 = iRec; 379 aOp[3].p3 = memId+1; 380 aOp[3].p5 = OPFLAG_APPEND; 381 sqlite3ReleaseTempReg(pParse, iRec); 382 } 383 } 384 void sqlite3AutoincrementEnd(Parse *pParse){ 385 if( pParse->pAinc ) autoIncrementEnd(pParse); 386 } 387 #else 388 /* 389 ** If SQLITE_OMIT_AUTOINCREMENT is defined, then the three routines 390 ** above are all no-ops 391 */ 392 # define autoIncBegin(A,B,C) (0) 393 # define autoIncStep(A,B,C) 394 #endif /* SQLITE_OMIT_AUTOINCREMENT */ 395 396 397 /* Forward declaration */ 398 static int xferOptimization( 399 Parse *pParse, /* Parser context */ 400 Table *pDest, /* The table we are inserting into */ 401 Select *pSelect, /* A SELECT statement to use as the data source */ 402 int onError, /* How to handle constraint errors */ 403 int iDbDest /* The database of pDest */ 404 ); 405 406 /* 407 ** This routine is called to handle SQL of the following forms: 408 ** 409 ** insert into TABLE (IDLIST) values(EXPRLIST),(EXPRLIST),... 410 ** insert into TABLE (IDLIST) select 411 ** insert into TABLE (IDLIST) default values 412 ** 413 ** The IDLIST following the table name is always optional. If omitted, 414 ** then a list of all (non-hidden) columns for the table is substituted. 415 ** The IDLIST appears in the pColumn parameter. pColumn is NULL if IDLIST 416 ** is omitted. 417 ** 418 ** For the pSelect parameter holds the values to be inserted for the 419 ** first two forms shown above. A VALUES clause is really just short-hand 420 ** for a SELECT statement that omits the FROM clause and everything else 421 ** that follows. If the pSelect parameter is NULL, that means that the 422 ** DEFAULT VALUES form of the INSERT statement is intended. 423 ** 424 ** The code generated follows one of four templates. For a simple 425 ** insert with data coming from a single-row VALUES clause, the code executes 426 ** once straight down through. Pseudo-code follows (we call this 427 ** the "1st template"): 428 ** 429 ** open write cursor to <table> and its indices 430 ** put VALUES clause expressions into registers 431 ** write the resulting record into <table> 432 ** cleanup 433 ** 434 ** The three remaining templates assume the statement is of the form 435 ** 436 ** INSERT INTO <table> SELECT ... 437 ** 438 ** If the SELECT clause is of the restricted form "SELECT * FROM <table2>" - 439 ** in other words if the SELECT pulls all columns from a single table 440 ** and there is no WHERE or LIMIT or GROUP BY or ORDER BY clauses, and 441 ** if <table2> and <table1> are distinct tables but have identical 442 ** schemas, including all the same indices, then a special optimization 443 ** is invoked that copies raw records from <table2> over to <table1>. 444 ** See the xferOptimization() function for the implementation of this 445 ** template. This is the 2nd template. 446 ** 447 ** open a write cursor to <table> 448 ** open read cursor on <table2> 449 ** transfer all records in <table2> over to <table> 450 ** close cursors 451 ** foreach index on <table> 452 ** open a write cursor on the <table> index 453 ** open a read cursor on the corresponding <table2> index 454 ** transfer all records from the read to the write cursors 455 ** close cursors 456 ** end foreach 457 ** 458 ** The 3rd template is for when the second template does not apply 459 ** and the SELECT clause does not read from <table> at any time. 460 ** The generated code follows this template: 461 ** 462 ** X <- A 463 ** goto B 464 ** A: setup for the SELECT 465 ** loop over the rows in the SELECT 466 ** load values into registers R..R+n 467 ** yield X 468 ** end loop 469 ** cleanup after the SELECT 470 ** end-coroutine X 471 ** B: open write cursor to <table> and its indices 472 ** C: yield X, at EOF goto D 473 ** insert the select result into <table> from R..R+n 474 ** goto C 475 ** D: cleanup 476 ** 477 ** The 4th template is used if the insert statement takes its 478 ** values from a SELECT but the data is being inserted into a table 479 ** that is also read as part of the SELECT. In the third form, 480 ** we have to use an intermediate table to store the results of 481 ** the select. The template is like this: 482 ** 483 ** X <- A 484 ** goto B 485 ** A: setup for the SELECT 486 ** loop over the tables in the SELECT 487 ** load value into register R..R+n 488 ** yield X 489 ** end loop 490 ** cleanup after the SELECT 491 ** end co-routine R 492 ** B: open temp table 493 ** L: yield X, at EOF goto M 494 ** insert row from R..R+n into temp table 495 ** goto L 496 ** M: open write cursor to <table> and its indices 497 ** rewind temp table 498 ** C: loop over rows of intermediate table 499 ** transfer values form intermediate table into <table> 500 ** end loop 501 ** D: cleanup 502 */ 503 void sqlite3Insert( 504 Parse *pParse, /* Parser context */ 505 SrcList *pTabList, /* Name of table into which we are inserting */ 506 Select *pSelect, /* A SELECT statement to use as the data source */ 507 IdList *pColumn, /* Column names corresponding to IDLIST. */ 508 int onError, /* How to handle constraint errors */ 509 Upsert *pUpsert /* ON CONFLICT clauses for upsert, or NULL */ 510 ){ 511 sqlite3 *db; /* The main database structure */ 512 Table *pTab; /* The table to insert into. aka TABLE */ 513 int i, j; /* Loop counters */ 514 Vdbe *v; /* Generate code into this virtual machine */ 515 Index *pIdx; /* For looping over indices of the table */ 516 int nColumn; /* Number of columns in the data */ 517 int nHidden = 0; /* Number of hidden columns if TABLE is virtual */ 518 int iDataCur = 0; /* VDBE cursor that is the main data repository */ 519 int iIdxCur = 0; /* First index cursor */ 520 int ipkColumn = -1; /* Column that is the INTEGER PRIMARY KEY */ 521 int endOfLoop; /* Label for the end of the insertion loop */ 522 int srcTab = 0; /* Data comes from this temporary cursor if >=0 */ 523 int addrInsTop = 0; /* Jump to label "D" */ 524 int addrCont = 0; /* Top of insert loop. Label "C" in templates 3 and 4 */ 525 SelectDest dest; /* Destination for SELECT on rhs of INSERT */ 526 int iDb; /* Index of database holding TABLE */ 527 u8 useTempTable = 0; /* Store SELECT results in intermediate table */ 528 u8 appendFlag = 0; /* True if the insert is likely to be an append */ 529 u8 withoutRowid; /* 0 for normal table. 1 for WITHOUT ROWID table */ 530 u8 bIdListInOrder; /* True if IDLIST is in table order */ 531 ExprList *pList = 0; /* List of VALUES() to be inserted */ 532 533 /* Register allocations */ 534 int regFromSelect = 0;/* Base register for data coming from SELECT */ 535 int regAutoinc = 0; /* Register holding the AUTOINCREMENT counter */ 536 int regRowCount = 0; /* Memory cell used for the row counter */ 537 int regIns; /* Block of regs holding rowid+data being inserted */ 538 int regRowid; /* registers holding insert rowid */ 539 int regData; /* register holding first column to insert */ 540 int *aRegIdx = 0; /* One register allocated to each index */ 541 542 #ifndef SQLITE_OMIT_TRIGGER 543 int isView; /* True if attempting to insert into a view */ 544 Trigger *pTrigger; /* List of triggers on pTab, if required */ 545 int tmask; /* Mask of trigger times */ 546 #endif 547 548 db = pParse->db; 549 if( pParse->nErr || db->mallocFailed ){ 550 goto insert_cleanup; 551 } 552 dest.iSDParm = 0; /* Suppress a harmless compiler warning */ 553 554 /* If the Select object is really just a simple VALUES() list with a 555 ** single row (the common case) then keep that one row of values 556 ** and discard the other (unused) parts of the pSelect object 557 */ 558 if( pSelect && (pSelect->selFlags & SF_Values)!=0 && pSelect->pPrior==0 ){ 559 pList = pSelect->pEList; 560 pSelect->pEList = 0; 561 sqlite3SelectDelete(db, pSelect); 562 pSelect = 0; 563 } 564 565 /* Locate the table into which we will be inserting new information. 566 */ 567 assert( pTabList->nSrc==1 ); 568 pTab = sqlite3SrcListLookup(pParse, pTabList); 569 if( pTab==0 ){ 570 goto insert_cleanup; 571 } 572 iDb = sqlite3SchemaToIndex(db, pTab->pSchema); 573 assert( iDb<db->nDb ); 574 if( sqlite3AuthCheck(pParse, SQLITE_INSERT, pTab->zName, 0, 575 db->aDb[iDb].zDbSName) ){ 576 goto insert_cleanup; 577 } 578 withoutRowid = !HasRowid(pTab); 579 580 /* Figure out if we have any triggers and if the table being 581 ** inserted into is a view 582 */ 583 #ifndef SQLITE_OMIT_TRIGGER 584 pTrigger = sqlite3TriggersExist(pParse, pTab, TK_INSERT, 0, &tmask); 585 isView = pTab->pSelect!=0; 586 #else 587 # define pTrigger 0 588 # define tmask 0 589 # define isView 0 590 #endif 591 #ifdef SQLITE_OMIT_VIEW 592 # undef isView 593 # define isView 0 594 #endif 595 assert( (pTrigger && tmask) || (pTrigger==0 && tmask==0) ); 596 597 /* If pTab is really a view, make sure it has been initialized. 598 ** ViewGetColumnNames() is a no-op if pTab is not a view. 599 */ 600 if( sqlite3ViewGetColumnNames(pParse, pTab) ){ 601 goto insert_cleanup; 602 } 603 604 /* Cannot insert into a read-only table. 605 */ 606 if( sqlite3IsReadOnly(pParse, pTab, tmask) ){ 607 goto insert_cleanup; 608 } 609 610 /* Allocate a VDBE 611 */ 612 v = sqlite3GetVdbe(pParse); 613 if( v==0 ) goto insert_cleanup; 614 if( pParse->nested==0 ) sqlite3VdbeCountChanges(v); 615 sqlite3BeginWriteOperation(pParse, pSelect || pTrigger, iDb); 616 617 #ifndef SQLITE_OMIT_XFER_OPT 618 /* If the statement is of the form 619 ** 620 ** INSERT INTO <table1> SELECT * FROM <table2>; 621 ** 622 ** Then special optimizations can be applied that make the transfer 623 ** very fast and which reduce fragmentation of indices. 624 ** 625 ** This is the 2nd template. 626 */ 627 if( pColumn==0 && xferOptimization(pParse, pTab, pSelect, onError, iDb) ){ 628 assert( !pTrigger ); 629 assert( pList==0 ); 630 goto insert_end; 631 } 632 #endif /* SQLITE_OMIT_XFER_OPT */ 633 634 /* If this is an AUTOINCREMENT table, look up the sequence number in the 635 ** sqlite_sequence table and store it in memory cell regAutoinc. 636 */ 637 regAutoinc = autoIncBegin(pParse, iDb, pTab); 638 639 /* Allocate registers for holding the rowid of the new row, 640 ** the content of the new row, and the assembled row record. 641 */ 642 regRowid = regIns = pParse->nMem+1; 643 pParse->nMem += pTab->nCol + 1; 644 if( IsVirtual(pTab) ){ 645 regRowid++; 646 pParse->nMem++; 647 } 648 regData = regRowid+1; 649 650 /* If the INSERT statement included an IDLIST term, then make sure 651 ** all elements of the IDLIST really are columns of the table and 652 ** remember the column indices. 653 ** 654 ** If the table has an INTEGER PRIMARY KEY column and that column 655 ** is named in the IDLIST, then record in the ipkColumn variable 656 ** the index into IDLIST of the primary key column. ipkColumn is 657 ** the index of the primary key as it appears in IDLIST, not as 658 ** is appears in the original table. (The index of the INTEGER 659 ** PRIMARY KEY in the original table is pTab->iPKey.) 660 */ 661 bIdListInOrder = (pTab->tabFlags & TF_OOOHidden)==0; 662 if( pColumn ){ 663 for(i=0; i<pColumn->nId; i++){ 664 pColumn->a[i].idx = -1; 665 } 666 for(i=0; i<pColumn->nId; i++){ 667 for(j=0; j<pTab->nCol; j++){ 668 if( sqlite3StrICmp(pColumn->a[i].zName, pTab->aCol[j].zName)==0 ){ 669 pColumn->a[i].idx = j; 670 if( i!=j ) bIdListInOrder = 0; 671 if( j==pTab->iPKey ){ 672 ipkColumn = i; assert( !withoutRowid ); 673 } 674 break; 675 } 676 } 677 if( j>=pTab->nCol ){ 678 if( sqlite3IsRowid(pColumn->a[i].zName) && !withoutRowid ){ 679 ipkColumn = i; 680 bIdListInOrder = 0; 681 }else{ 682 sqlite3ErrorMsg(pParse, "table %S has no column named %s", 683 pTabList, 0, pColumn->a[i].zName); 684 pParse->checkSchema = 1; 685 goto insert_cleanup; 686 } 687 } 688 } 689 } 690 691 /* Figure out how many columns of data are supplied. If the data 692 ** is coming from a SELECT statement, then generate a co-routine that 693 ** produces a single row of the SELECT on each invocation. The 694 ** co-routine is the common header to the 3rd and 4th templates. 695 */ 696 if( pSelect ){ 697 /* Data is coming from a SELECT or from a multi-row VALUES clause. 698 ** Generate a co-routine to run the SELECT. */ 699 int regYield; /* Register holding co-routine entry-point */ 700 int addrTop; /* Top of the co-routine */ 701 int rc; /* Result code */ 702 703 regYield = ++pParse->nMem; 704 addrTop = sqlite3VdbeCurrentAddr(v) + 1; 705 sqlite3VdbeAddOp3(v, OP_InitCoroutine, regYield, 0, addrTop); 706 sqlite3SelectDestInit(&dest, SRT_Coroutine, regYield); 707 dest.iSdst = bIdListInOrder ? regData : 0; 708 dest.nSdst = pTab->nCol; 709 rc = sqlite3Select(pParse, pSelect, &dest); 710 regFromSelect = dest.iSdst; 711 if( rc || db->mallocFailed || pParse->nErr ) goto insert_cleanup; 712 sqlite3VdbeEndCoroutine(v, regYield); 713 sqlite3VdbeJumpHere(v, addrTop - 1); /* label B: */ 714 assert( pSelect->pEList ); 715 nColumn = pSelect->pEList->nExpr; 716 717 /* Set useTempTable to TRUE if the result of the SELECT statement 718 ** should be written into a temporary table (template 4). Set to 719 ** FALSE if each output row of the SELECT can be written directly into 720 ** the destination table (template 3). 721 ** 722 ** A temp table must be used if the table being updated is also one 723 ** of the tables being read by the SELECT statement. Also use a 724 ** temp table in the case of row triggers. 725 */ 726 if( pTrigger || readsTable(pParse, iDb, pTab) ){ 727 useTempTable = 1; 728 } 729 730 if( useTempTable ){ 731 /* Invoke the coroutine to extract information from the SELECT 732 ** and add it to a transient table srcTab. The code generated 733 ** here is from the 4th template: 734 ** 735 ** B: open temp table 736 ** L: yield X, goto M at EOF 737 ** insert row from R..R+n into temp table 738 ** goto L 739 ** M: ... 740 */ 741 int regRec; /* Register to hold packed record */ 742 int regTempRowid; /* Register to hold temp table ROWID */ 743 int addrL; /* Label "L" */ 744 745 srcTab = pParse->nTab++; 746 regRec = sqlite3GetTempReg(pParse); 747 regTempRowid = sqlite3GetTempReg(pParse); 748 sqlite3VdbeAddOp2(v, OP_OpenEphemeral, srcTab, nColumn); 749 addrL = sqlite3VdbeAddOp1(v, OP_Yield, dest.iSDParm); VdbeCoverage(v); 750 sqlite3VdbeAddOp3(v, OP_MakeRecord, regFromSelect, nColumn, regRec); 751 sqlite3VdbeAddOp2(v, OP_NewRowid, srcTab, regTempRowid); 752 sqlite3VdbeAddOp3(v, OP_Insert, srcTab, regRec, regTempRowid); 753 sqlite3VdbeGoto(v, addrL); 754 sqlite3VdbeJumpHere(v, addrL); 755 sqlite3ReleaseTempReg(pParse, regRec); 756 sqlite3ReleaseTempReg(pParse, regTempRowid); 757 } 758 }else{ 759 /* This is the case if the data for the INSERT is coming from a 760 ** single-row VALUES clause 761 */ 762 NameContext sNC; 763 memset(&sNC, 0, sizeof(sNC)); 764 sNC.pParse = pParse; 765 srcTab = -1; 766 assert( useTempTable==0 ); 767 if( pList ){ 768 nColumn = pList->nExpr; 769 if( sqlite3ResolveExprListNames(&sNC, pList) ){ 770 goto insert_cleanup; 771 } 772 }else{ 773 nColumn = 0; 774 } 775 } 776 777 /* If there is no IDLIST term but the table has an integer primary 778 ** key, the set the ipkColumn variable to the integer primary key 779 ** column index in the original table definition. 780 */ 781 if( pColumn==0 && nColumn>0 ){ 782 ipkColumn = pTab->iPKey; 783 } 784 785 /* Make sure the number of columns in the source data matches the number 786 ** of columns to be inserted into the table. 787 */ 788 for(i=0; i<pTab->nCol; i++){ 789 nHidden += (IsHiddenColumn(&pTab->aCol[i]) ? 1 : 0); 790 } 791 if( pColumn==0 && nColumn && nColumn!=(pTab->nCol-nHidden) ){ 792 sqlite3ErrorMsg(pParse, 793 "table %S has %d columns but %d values were supplied", 794 pTabList, 0, pTab->nCol-nHidden, nColumn); 795 goto insert_cleanup; 796 } 797 if( pColumn!=0 && nColumn!=pColumn->nId ){ 798 sqlite3ErrorMsg(pParse, "%d values for %d columns", nColumn, pColumn->nId); 799 goto insert_cleanup; 800 } 801 802 /* Initialize the count of rows to be inserted 803 */ 804 if( (db->flags & SQLITE_CountRows)!=0 805 && !pParse->nested 806 && !pParse->pTriggerTab 807 ){ 808 regRowCount = ++pParse->nMem; 809 sqlite3VdbeAddOp2(v, OP_Integer, 0, regRowCount); 810 } 811 812 /* If this is not a view, open the table and and all indices */ 813 if( !isView ){ 814 int nIdx; 815 nIdx = sqlite3OpenTableAndIndices(pParse, pTab, OP_OpenWrite, 0, -1, 0, 816 &iDataCur, &iIdxCur); 817 aRegIdx = sqlite3DbMallocRawNN(db, sizeof(int)*(nIdx+1)); 818 if( aRegIdx==0 ){ 819 goto insert_cleanup; 820 } 821 for(i=0, pIdx=pTab->pIndex; i<nIdx; pIdx=pIdx->pNext, i++){ 822 assert( pIdx ); 823 aRegIdx[i] = ++pParse->nMem; 824 pParse->nMem += pIdx->nColumn; 825 } 826 } 827 #ifndef SQLITE_OMIT_UPSERT 828 if( pUpsert ){ 829 if( IsVirtual(pTab) ){ 830 sqlite3ErrorMsg(pParse, "UPSERT not implemented for virtual table \"%s\"", 831 pTab->zName); 832 goto insert_cleanup; 833 } 834 pTabList->a[0].iCursor = iDataCur; 835 pUpsert->pUpsertSrc = pTabList; 836 pUpsert->regData = regData; 837 pUpsert->iDataCur = iDataCur; 838 pUpsert->iIdxCur = iIdxCur; 839 if( pUpsert->pUpsertTarget ){ 840 sqlite3UpsertAnalyzeTarget(pParse, pTabList, pUpsert); 841 } 842 } 843 #endif 844 845 846 /* This is the top of the main insertion loop */ 847 if( useTempTable ){ 848 /* This block codes the top of loop only. The complete loop is the 849 ** following pseudocode (template 4): 850 ** 851 ** rewind temp table, if empty goto D 852 ** C: loop over rows of intermediate table 853 ** transfer values form intermediate table into <table> 854 ** end loop 855 ** D: ... 856 */ 857 addrInsTop = sqlite3VdbeAddOp1(v, OP_Rewind, srcTab); VdbeCoverage(v); 858 addrCont = sqlite3VdbeCurrentAddr(v); 859 }else if( pSelect ){ 860 /* This block codes the top of loop only. The complete loop is the 861 ** following pseudocode (template 3): 862 ** 863 ** C: yield X, at EOF goto D 864 ** insert the select result into <table> from R..R+n 865 ** goto C 866 ** D: ... 867 */ 868 addrInsTop = addrCont = sqlite3VdbeAddOp1(v, OP_Yield, dest.iSDParm); 869 VdbeCoverage(v); 870 } 871 872 /* Run the BEFORE and INSTEAD OF triggers, if there are any 873 */ 874 endOfLoop = sqlite3VdbeMakeLabel(pParse); 875 if( tmask & TRIGGER_BEFORE ){ 876 int regCols = sqlite3GetTempRange(pParse, pTab->nCol+1); 877 878 /* build the NEW.* reference row. Note that if there is an INTEGER 879 ** PRIMARY KEY into which a NULL is being inserted, that NULL will be 880 ** translated into a unique ID for the row. But on a BEFORE trigger, 881 ** we do not know what the unique ID will be (because the insert has 882 ** not happened yet) so we substitute a rowid of -1 883 */ 884 if( ipkColumn<0 ){ 885 sqlite3VdbeAddOp2(v, OP_Integer, -1, regCols); 886 }else{ 887 int addr1; 888 assert( !withoutRowid ); 889 if( useTempTable ){ 890 sqlite3VdbeAddOp3(v, OP_Column, srcTab, ipkColumn, regCols); 891 }else{ 892 assert( pSelect==0 ); /* Otherwise useTempTable is true */ 893 sqlite3ExprCode(pParse, pList->a[ipkColumn].pExpr, regCols); 894 } 895 addr1 = sqlite3VdbeAddOp1(v, OP_NotNull, regCols); VdbeCoverage(v); 896 sqlite3VdbeAddOp2(v, OP_Integer, -1, regCols); 897 sqlite3VdbeJumpHere(v, addr1); 898 sqlite3VdbeAddOp1(v, OP_MustBeInt, regCols); VdbeCoverage(v); 899 } 900 901 /* Cannot have triggers on a virtual table. If it were possible, 902 ** this block would have to account for hidden column. 903 */ 904 assert( !IsVirtual(pTab) ); 905 906 /* Create the new column data 907 */ 908 for(i=j=0; i<pTab->nCol; i++){ 909 if( pColumn ){ 910 for(j=0; j<pColumn->nId; j++){ 911 if( pColumn->a[j].idx==i ) break; 912 } 913 } 914 if( (!useTempTable && !pList) || (pColumn && j>=pColumn->nId) 915 || (pColumn==0 && IsOrdinaryHiddenColumn(&pTab->aCol[i])) ){ 916 sqlite3ExprCode(pParse, pTab->aCol[i].pDflt, regCols+i+1); 917 }else if( useTempTable ){ 918 sqlite3VdbeAddOp3(v, OP_Column, srcTab, j, regCols+i+1); 919 }else{ 920 assert( pSelect==0 ); /* Otherwise useTempTable is true */ 921 sqlite3ExprCodeAndCache(pParse, pList->a[j].pExpr, regCols+i+1); 922 } 923 if( pColumn==0 && !IsOrdinaryHiddenColumn(&pTab->aCol[i]) ) j++; 924 } 925 926 /* If this is an INSERT on a view with an INSTEAD OF INSERT trigger, 927 ** do not attempt any conversions before assembling the record. 928 ** If this is a real table, attempt conversions as required by the 929 ** table column affinities. 930 */ 931 if( !isView ){ 932 sqlite3TableAffinity(v, pTab, regCols+1); 933 } 934 935 /* Fire BEFORE or INSTEAD OF triggers */ 936 sqlite3CodeRowTrigger(pParse, pTrigger, TK_INSERT, 0, TRIGGER_BEFORE, 937 pTab, regCols-pTab->nCol-1, onError, endOfLoop); 938 939 sqlite3ReleaseTempRange(pParse, regCols, pTab->nCol+1); 940 } 941 942 /* Compute the content of the next row to insert into a range of 943 ** registers beginning at regIns. 944 */ 945 if( !isView ){ 946 if( IsVirtual(pTab) ){ 947 /* The row that the VUpdate opcode will delete: none */ 948 sqlite3VdbeAddOp2(v, OP_Null, 0, regIns); 949 } 950 if( ipkColumn>=0 ){ 951 if( useTempTable ){ 952 sqlite3VdbeAddOp3(v, OP_Column, srcTab, ipkColumn, regRowid); 953 }else if( pSelect ){ 954 sqlite3VdbeAddOp2(v, OP_Copy, regFromSelect+ipkColumn, regRowid); 955 }else{ 956 Expr *pIpk = pList->a[ipkColumn].pExpr; 957 if( pIpk->op==TK_NULL && !IsVirtual(pTab) ){ 958 sqlite3VdbeAddOp3(v, OP_NewRowid, iDataCur, regRowid, regAutoinc); 959 appendFlag = 1; 960 }else{ 961 sqlite3ExprCode(pParse, pList->a[ipkColumn].pExpr, regRowid); 962 } 963 } 964 /* If the PRIMARY KEY expression is NULL, then use OP_NewRowid 965 ** to generate a unique primary key value. 966 */ 967 if( !appendFlag ){ 968 int addr1; 969 if( !IsVirtual(pTab) ){ 970 addr1 = sqlite3VdbeAddOp1(v, OP_NotNull, regRowid); VdbeCoverage(v); 971 sqlite3VdbeAddOp3(v, OP_NewRowid, iDataCur, regRowid, regAutoinc); 972 sqlite3VdbeJumpHere(v, addr1); 973 }else{ 974 addr1 = sqlite3VdbeCurrentAddr(v); 975 sqlite3VdbeAddOp2(v, OP_IsNull, regRowid, addr1+2); VdbeCoverage(v); 976 } 977 sqlite3VdbeAddOp1(v, OP_MustBeInt, regRowid); VdbeCoverage(v); 978 } 979 }else if( IsVirtual(pTab) || withoutRowid ){ 980 sqlite3VdbeAddOp2(v, OP_Null, 0, regRowid); 981 }else{ 982 sqlite3VdbeAddOp3(v, OP_NewRowid, iDataCur, regRowid, regAutoinc); 983 appendFlag = 1; 984 } 985 autoIncStep(pParse, regAutoinc, regRowid); 986 987 /* Compute data for all columns of the new entry, beginning 988 ** with the first column. 989 */ 990 nHidden = 0; 991 for(i=0; i<pTab->nCol; i++){ 992 int iRegStore = regRowid+1+i; 993 if( i==pTab->iPKey ){ 994 /* The value of the INTEGER PRIMARY KEY column is always a NULL. 995 ** Whenever this column is read, the rowid will be substituted 996 ** in its place. Hence, fill this column with a NULL to avoid 997 ** taking up data space with information that will never be used. 998 ** As there may be shallow copies of this value, make it a soft-NULL */ 999 sqlite3VdbeAddOp1(v, OP_SoftNull, iRegStore); 1000 continue; 1001 } 1002 if( pColumn==0 ){ 1003 if( IsHiddenColumn(&pTab->aCol[i]) ){ 1004 j = -1; 1005 nHidden++; 1006 }else{ 1007 j = i - nHidden; 1008 } 1009 }else{ 1010 for(j=0; j<pColumn->nId; j++){ 1011 if( pColumn->a[j].idx==i ) break; 1012 } 1013 } 1014 if( j<0 || nColumn==0 || (pColumn && j>=pColumn->nId) ){ 1015 sqlite3ExprCodeFactorable(pParse, pTab->aCol[i].pDflt, iRegStore); 1016 }else if( useTempTable ){ 1017 sqlite3VdbeAddOp3(v, OP_Column, srcTab, j, iRegStore); 1018 }else if( pSelect ){ 1019 if( regFromSelect!=regData ){ 1020 sqlite3VdbeAddOp2(v, OP_SCopy, regFromSelect+j, iRegStore); 1021 } 1022 }else{ 1023 sqlite3ExprCode(pParse, pList->a[j].pExpr, iRegStore); 1024 } 1025 } 1026 1027 /* Generate code to check constraints and generate index keys and 1028 ** do the insertion. 1029 */ 1030 #ifndef SQLITE_OMIT_VIRTUALTABLE 1031 if( IsVirtual(pTab) ){ 1032 const char *pVTab = (const char *)sqlite3GetVTable(db, pTab); 1033 sqlite3VtabMakeWritable(pParse, pTab); 1034 sqlite3VdbeAddOp4(v, OP_VUpdate, 1, pTab->nCol+2, regIns, pVTab, P4_VTAB); 1035 sqlite3VdbeChangeP5(v, onError==OE_Default ? OE_Abort : onError); 1036 sqlite3MayAbort(pParse); 1037 }else 1038 #endif 1039 { 1040 int isReplace; /* Set to true if constraints may cause a replace */ 1041 int bUseSeek; /* True to use OPFLAG_SEEKRESULT */ 1042 sqlite3GenerateConstraintChecks(pParse, pTab, aRegIdx, iDataCur, iIdxCur, 1043 regIns, 0, ipkColumn>=0, onError, endOfLoop, &isReplace, 0, pUpsert 1044 ); 1045 sqlite3FkCheck(pParse, pTab, 0, regIns, 0, 0); 1046 1047 /* Set the OPFLAG_USESEEKRESULT flag if either (a) there are no REPLACE 1048 ** constraints or (b) there are no triggers and this table is not a 1049 ** parent table in a foreign key constraint. It is safe to set the 1050 ** flag in the second case as if any REPLACE constraint is hit, an 1051 ** OP_Delete or OP_IdxDelete instruction will be executed on each 1052 ** cursor that is disturbed. And these instructions both clear the 1053 ** VdbeCursor.seekResult variable, disabling the OPFLAG_USESEEKRESULT 1054 ** functionality. */ 1055 bUseSeek = (isReplace==0 || (pTrigger==0 && 1056 ((db->flags & SQLITE_ForeignKeys)==0 || sqlite3FkReferences(pTab)==0) 1057 )); 1058 sqlite3CompleteInsertion(pParse, pTab, iDataCur, iIdxCur, 1059 regIns, aRegIdx, 0, appendFlag, bUseSeek 1060 ); 1061 } 1062 } 1063 1064 /* Update the count of rows that are inserted 1065 */ 1066 if( regRowCount ){ 1067 sqlite3VdbeAddOp2(v, OP_AddImm, regRowCount, 1); 1068 } 1069 1070 if( pTrigger ){ 1071 /* Code AFTER triggers */ 1072 sqlite3CodeRowTrigger(pParse, pTrigger, TK_INSERT, 0, TRIGGER_AFTER, 1073 pTab, regData-2-pTab->nCol, onError, endOfLoop); 1074 } 1075 1076 /* The bottom of the main insertion loop, if the data source 1077 ** is a SELECT statement. 1078 */ 1079 sqlite3VdbeResolveLabel(v, endOfLoop); 1080 if( useTempTable ){ 1081 sqlite3VdbeAddOp2(v, OP_Next, srcTab, addrCont); VdbeCoverage(v); 1082 sqlite3VdbeJumpHere(v, addrInsTop); 1083 sqlite3VdbeAddOp1(v, OP_Close, srcTab); 1084 }else if( pSelect ){ 1085 sqlite3VdbeGoto(v, addrCont); 1086 sqlite3VdbeJumpHere(v, addrInsTop); 1087 } 1088 1089 insert_end: 1090 /* Update the sqlite_sequence table by storing the content of the 1091 ** maximum rowid counter values recorded while inserting into 1092 ** autoincrement tables. 1093 */ 1094 if( pParse->nested==0 && pParse->pTriggerTab==0 ){ 1095 sqlite3AutoincrementEnd(pParse); 1096 } 1097 1098 /* 1099 ** Return the number of rows inserted. If this routine is 1100 ** generating code because of a call to sqlite3NestedParse(), do not 1101 ** invoke the callback function. 1102 */ 1103 if( regRowCount ){ 1104 sqlite3VdbeAddOp2(v, OP_ResultRow, regRowCount, 1); 1105 sqlite3VdbeSetNumCols(v, 1); 1106 sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows inserted", SQLITE_STATIC); 1107 } 1108 1109 insert_cleanup: 1110 sqlite3SrcListDelete(db, pTabList); 1111 sqlite3ExprListDelete(db, pList); 1112 sqlite3UpsertDelete(db, pUpsert); 1113 sqlite3SelectDelete(db, pSelect); 1114 sqlite3IdListDelete(db, pColumn); 1115 sqlite3DbFree(db, aRegIdx); 1116 } 1117 1118 /* Make sure "isView" and other macros defined above are undefined. Otherwise 1119 ** they may interfere with compilation of other functions in this file 1120 ** (or in another file, if this file becomes part of the amalgamation). */ 1121 #ifdef isView 1122 #undef isView 1123 #endif 1124 #ifdef pTrigger 1125 #undef pTrigger 1126 #endif 1127 #ifdef tmask 1128 #undef tmask 1129 #endif 1130 1131 /* 1132 ** Meanings of bits in of pWalker->eCode for 1133 ** sqlite3ExprReferencesUpdatedColumn() 1134 */ 1135 #define CKCNSTRNT_COLUMN 0x01 /* CHECK constraint uses a changing column */ 1136 #define CKCNSTRNT_ROWID 0x02 /* CHECK constraint references the ROWID */ 1137 1138 /* This is the Walker callback from sqlite3ExprReferencesUpdatedColumn(). 1139 * Set bit 0x01 of pWalker->eCode if pWalker->eCode to 0 and if this 1140 ** expression node references any of the 1141 ** columns that are being modifed by an UPDATE statement. 1142 */ 1143 static int checkConstraintExprNode(Walker *pWalker, Expr *pExpr){ 1144 if( pExpr->op==TK_COLUMN ){ 1145 assert( pExpr->iColumn>=0 || pExpr->iColumn==-1 ); 1146 if( pExpr->iColumn>=0 ){ 1147 if( pWalker->u.aiCol[pExpr->iColumn]>=0 ){ 1148 pWalker->eCode |= CKCNSTRNT_COLUMN; 1149 } 1150 }else{ 1151 pWalker->eCode |= CKCNSTRNT_ROWID; 1152 } 1153 } 1154 return WRC_Continue; 1155 } 1156 1157 /* 1158 ** pExpr is a CHECK constraint on a row that is being UPDATE-ed. The 1159 ** only columns that are modified by the UPDATE are those for which 1160 ** aiChng[i]>=0, and also the ROWID is modified if chngRowid is true. 1161 ** 1162 ** Return true if CHECK constraint pExpr uses any of the 1163 ** changing columns (or the rowid if it is changing). In other words, 1164 ** return true if this CHECK constraint must be validated for 1165 ** the new row in the UPDATE statement. 1166 ** 1167 ** 2018-09-15: pExpr might also be an expression for an index-on-expressions. 1168 ** The operation of this routine is the same - return true if an only if 1169 ** the expression uses one or more of columns identified by the second and 1170 ** third arguments. 1171 */ 1172 int sqlite3ExprReferencesUpdatedColumn( 1173 Expr *pExpr, /* The expression to be checked */ 1174 int *aiChng, /* aiChng[x]>=0 if column x changed by the UPDATE */ 1175 int chngRowid /* True if UPDATE changes the rowid */ 1176 ){ 1177 Walker w; 1178 memset(&w, 0, sizeof(w)); 1179 w.eCode = 0; 1180 w.xExprCallback = checkConstraintExprNode; 1181 w.u.aiCol = aiChng; 1182 sqlite3WalkExpr(&w, pExpr); 1183 if( !chngRowid ){ 1184 testcase( (w.eCode & CKCNSTRNT_ROWID)!=0 ); 1185 w.eCode &= ~CKCNSTRNT_ROWID; 1186 } 1187 testcase( w.eCode==0 ); 1188 testcase( w.eCode==CKCNSTRNT_COLUMN ); 1189 testcase( w.eCode==CKCNSTRNT_ROWID ); 1190 testcase( w.eCode==(CKCNSTRNT_ROWID|CKCNSTRNT_COLUMN) ); 1191 return w.eCode!=0; 1192 } 1193 1194 /* 1195 ** Generate code to do constraint checks prior to an INSERT or an UPDATE 1196 ** on table pTab. 1197 ** 1198 ** The regNewData parameter is the first register in a range that contains 1199 ** the data to be inserted or the data after the update. There will be 1200 ** pTab->nCol+1 registers in this range. The first register (the one 1201 ** that regNewData points to) will contain the new rowid, or NULL in the 1202 ** case of a WITHOUT ROWID table. The second register in the range will 1203 ** contain the content of the first table column. The third register will 1204 ** contain the content of the second table column. And so forth. 1205 ** 1206 ** The regOldData parameter is similar to regNewData except that it contains 1207 ** the data prior to an UPDATE rather than afterwards. regOldData is zero 1208 ** for an INSERT. This routine can distinguish between UPDATE and INSERT by 1209 ** checking regOldData for zero. 1210 ** 1211 ** For an UPDATE, the pkChng boolean is true if the true primary key (the 1212 ** rowid for a normal table or the PRIMARY KEY for a WITHOUT ROWID table) 1213 ** might be modified by the UPDATE. If pkChng is false, then the key of 1214 ** the iDataCur content table is guaranteed to be unchanged by the UPDATE. 1215 ** 1216 ** For an INSERT, the pkChng boolean indicates whether or not the rowid 1217 ** was explicitly specified as part of the INSERT statement. If pkChng 1218 ** is zero, it means that the either rowid is computed automatically or 1219 ** that the table is a WITHOUT ROWID table and has no rowid. On an INSERT, 1220 ** pkChng will only be true if the INSERT statement provides an integer 1221 ** value for either the rowid column or its INTEGER PRIMARY KEY alias. 1222 ** 1223 ** The code generated by this routine will store new index entries into 1224 ** registers identified by aRegIdx[]. No index entry is created for 1225 ** indices where aRegIdx[i]==0. The order of indices in aRegIdx[] is 1226 ** the same as the order of indices on the linked list of indices 1227 ** at pTab->pIndex. 1228 ** 1229 ** The caller must have already opened writeable cursors on the main 1230 ** table and all applicable indices (that is to say, all indices for which 1231 ** aRegIdx[] is not zero). iDataCur is the cursor for the main table when 1232 ** inserting or updating a rowid table, or the cursor for the PRIMARY KEY 1233 ** index when operating on a WITHOUT ROWID table. iIdxCur is the cursor 1234 ** for the first index in the pTab->pIndex list. Cursors for other indices 1235 ** are at iIdxCur+N for the N-th element of the pTab->pIndex list. 1236 ** 1237 ** This routine also generates code to check constraints. NOT NULL, 1238 ** CHECK, and UNIQUE constraints are all checked. If a constraint fails, 1239 ** then the appropriate action is performed. There are five possible 1240 ** actions: ROLLBACK, ABORT, FAIL, REPLACE, and IGNORE. 1241 ** 1242 ** Constraint type Action What Happens 1243 ** --------------- ---------- ---------------------------------------- 1244 ** any ROLLBACK The current transaction is rolled back and 1245 ** sqlite3_step() returns immediately with a 1246 ** return code of SQLITE_CONSTRAINT. 1247 ** 1248 ** any ABORT Back out changes from the current command 1249 ** only (do not do a complete rollback) then 1250 ** cause sqlite3_step() to return immediately 1251 ** with SQLITE_CONSTRAINT. 1252 ** 1253 ** any FAIL Sqlite3_step() returns immediately with a 1254 ** return code of SQLITE_CONSTRAINT. The 1255 ** transaction is not rolled back and any 1256 ** changes to prior rows are retained. 1257 ** 1258 ** any IGNORE The attempt in insert or update the current 1259 ** row is skipped, without throwing an error. 1260 ** Processing continues with the next row. 1261 ** (There is an immediate jump to ignoreDest.) 1262 ** 1263 ** NOT NULL REPLACE The NULL value is replace by the default 1264 ** value for that column. If the default value 1265 ** is NULL, the action is the same as ABORT. 1266 ** 1267 ** UNIQUE REPLACE The other row that conflicts with the row 1268 ** being inserted is removed. 1269 ** 1270 ** CHECK REPLACE Illegal. The results in an exception. 1271 ** 1272 ** Which action to take is determined by the overrideError parameter. 1273 ** Or if overrideError==OE_Default, then the pParse->onError parameter 1274 ** is used. Or if pParse->onError==OE_Default then the onError value 1275 ** for the constraint is used. 1276 */ 1277 void sqlite3GenerateConstraintChecks( 1278 Parse *pParse, /* The parser context */ 1279 Table *pTab, /* The table being inserted or updated */ 1280 int *aRegIdx, /* Use register aRegIdx[i] for index i. 0 for unused */ 1281 int iDataCur, /* Canonical data cursor (main table or PK index) */ 1282 int iIdxCur, /* First index cursor */ 1283 int regNewData, /* First register in a range holding values to insert */ 1284 int regOldData, /* Previous content. 0 for INSERTs */ 1285 u8 pkChng, /* Non-zero if the rowid or PRIMARY KEY changed */ 1286 u8 overrideError, /* Override onError to this if not OE_Default */ 1287 int ignoreDest, /* Jump to this label on an OE_Ignore resolution */ 1288 int *pbMayReplace, /* OUT: Set to true if constraint may cause a replace */ 1289 int *aiChng, /* column i is unchanged if aiChng[i]<0 */ 1290 Upsert *pUpsert /* ON CONFLICT clauses, if any. NULL otherwise */ 1291 ){ 1292 Vdbe *v; /* VDBE under constrution */ 1293 Index *pIdx; /* Pointer to one of the indices */ 1294 Index *pPk = 0; /* The PRIMARY KEY index */ 1295 sqlite3 *db; /* Database connection */ 1296 int i; /* loop counter */ 1297 int ix; /* Index loop counter */ 1298 int nCol; /* Number of columns */ 1299 int onError; /* Conflict resolution strategy */ 1300 int addr1; /* Address of jump instruction */ 1301 int seenReplace = 0; /* True if REPLACE is used to resolve INT PK conflict */ 1302 int nPkField; /* Number of fields in PRIMARY KEY. 1 for ROWID tables */ 1303 Index *pUpIdx = 0; /* Index to which to apply the upsert */ 1304 u8 isUpdate; /* True if this is an UPDATE operation */ 1305 u8 bAffinityDone = 0; /* True if the OP_Affinity operation has been run */ 1306 int upsertBypass = 0; /* Address of Goto to bypass upsert subroutine */ 1307 int upsertJump = 0; /* Address of Goto that jumps into upsert subroutine */ 1308 int ipkTop = 0; /* Top of the IPK uniqueness check */ 1309 int ipkBottom = 0; /* OP_Goto at the end of the IPK uniqueness check */ 1310 1311 isUpdate = regOldData!=0; 1312 db = pParse->db; 1313 v = sqlite3GetVdbe(pParse); 1314 assert( v!=0 ); 1315 assert( pTab->pSelect==0 ); /* This table is not a VIEW */ 1316 nCol = pTab->nCol; 1317 1318 /* pPk is the PRIMARY KEY index for WITHOUT ROWID tables and NULL for 1319 ** normal rowid tables. nPkField is the number of key fields in the 1320 ** pPk index or 1 for a rowid table. In other words, nPkField is the 1321 ** number of fields in the true primary key of the table. */ 1322 if( HasRowid(pTab) ){ 1323 pPk = 0; 1324 nPkField = 1; 1325 }else{ 1326 pPk = sqlite3PrimaryKeyIndex(pTab); 1327 nPkField = pPk->nKeyCol; 1328 } 1329 1330 /* Record that this module has started */ 1331 VdbeModuleComment((v, "BEGIN: GenCnstCks(%d,%d,%d,%d,%d)", 1332 iDataCur, iIdxCur, regNewData, regOldData, pkChng)); 1333 1334 /* Test all NOT NULL constraints. 1335 */ 1336 for(i=0; i<nCol; i++){ 1337 if( i==pTab->iPKey ){ 1338 continue; /* ROWID is never NULL */ 1339 } 1340 if( aiChng && aiChng[i]<0 ){ 1341 /* Don't bother checking for NOT NULL on columns that do not change */ 1342 continue; 1343 } 1344 onError = pTab->aCol[i].notNull; 1345 if( onError==OE_None ) continue; /* This column is allowed to be NULL */ 1346 if( overrideError!=OE_Default ){ 1347 onError = overrideError; 1348 }else if( onError==OE_Default ){ 1349 onError = OE_Abort; 1350 } 1351 if( onError==OE_Replace && pTab->aCol[i].pDflt==0 ){ 1352 onError = OE_Abort; 1353 } 1354 assert( onError==OE_Rollback || onError==OE_Abort || onError==OE_Fail 1355 || onError==OE_Ignore || onError==OE_Replace ); 1356 addr1 = 0; 1357 switch( onError ){ 1358 case OE_Replace: { 1359 assert( onError==OE_Replace ); 1360 addr1 = sqlite3VdbeMakeLabel(pParse); 1361 sqlite3VdbeAddOp2(v, OP_NotNull, regNewData+1+i, addr1); 1362 VdbeCoverage(v); 1363 sqlite3ExprCode(pParse, pTab->aCol[i].pDflt, regNewData+1+i); 1364 sqlite3VdbeAddOp2(v, OP_NotNull, regNewData+1+i, addr1); 1365 VdbeCoverage(v); 1366 onError = OE_Abort; 1367 /* Fall through into the OE_Abort case to generate code that runs 1368 ** if both the input and the default value are NULL */ 1369 } 1370 case OE_Abort: 1371 sqlite3MayAbort(pParse); 1372 /* Fall through */ 1373 case OE_Rollback: 1374 case OE_Fail: { 1375 char *zMsg = sqlite3MPrintf(db, "%s.%s", pTab->zName, 1376 pTab->aCol[i].zName); 1377 sqlite3VdbeAddOp3(v, OP_HaltIfNull, SQLITE_CONSTRAINT_NOTNULL, onError, 1378 regNewData+1+i); 1379 sqlite3VdbeAppendP4(v, zMsg, P4_DYNAMIC); 1380 sqlite3VdbeChangeP5(v, P5_ConstraintNotNull); 1381 VdbeCoverage(v); 1382 if( addr1 ) sqlite3VdbeResolveLabel(v, addr1); 1383 break; 1384 } 1385 default: { 1386 assert( onError==OE_Ignore ); 1387 sqlite3VdbeAddOp2(v, OP_IsNull, regNewData+1+i, ignoreDest); 1388 VdbeCoverage(v); 1389 break; 1390 } 1391 } 1392 } 1393 1394 /* Test all CHECK constraints 1395 */ 1396 #ifndef SQLITE_OMIT_CHECK 1397 if( pTab->pCheck && (db->flags & SQLITE_IgnoreChecks)==0 ){ 1398 ExprList *pCheck = pTab->pCheck; 1399 pParse->iSelfTab = -(regNewData+1); 1400 onError = overrideError!=OE_Default ? overrideError : OE_Abort; 1401 for(i=0; i<pCheck->nExpr; i++){ 1402 int allOk; 1403 Expr *pExpr = pCheck->a[i].pExpr; 1404 if( aiChng 1405 && !sqlite3ExprReferencesUpdatedColumn(pExpr, aiChng, pkChng) 1406 ){ 1407 /* The check constraints do not reference any of the columns being 1408 ** updated so there is no point it verifying the check constraint */ 1409 continue; 1410 } 1411 allOk = sqlite3VdbeMakeLabel(pParse); 1412 sqlite3VdbeVerifyAbortable(v, onError); 1413 sqlite3ExprIfTrue(pParse, pExpr, allOk, SQLITE_JUMPIFNULL); 1414 if( onError==OE_Ignore ){ 1415 sqlite3VdbeGoto(v, ignoreDest); 1416 }else{ 1417 char *zName = pCheck->a[i].zName; 1418 if( zName==0 ) zName = pTab->zName; 1419 if( onError==OE_Replace ) onError = OE_Abort; /* IMP: R-15569-63625 */ 1420 sqlite3HaltConstraint(pParse, SQLITE_CONSTRAINT_CHECK, 1421 onError, zName, P4_TRANSIENT, 1422 P5_ConstraintCheck); 1423 } 1424 sqlite3VdbeResolveLabel(v, allOk); 1425 } 1426 pParse->iSelfTab = 0; 1427 } 1428 #endif /* !defined(SQLITE_OMIT_CHECK) */ 1429 1430 /* UNIQUE and PRIMARY KEY constraints should be handled in the following 1431 ** order: 1432 ** 1433 ** (1) OE_Update 1434 ** (2) OE_Abort, OE_Fail, OE_Rollback, OE_Ignore 1435 ** (3) OE_Replace 1436 ** 1437 ** OE_Fail and OE_Ignore must happen before any changes are made. 1438 ** OE_Update guarantees that only a single row will change, so it 1439 ** must happen before OE_Replace. Technically, OE_Abort and OE_Rollback 1440 ** could happen in any order, but they are grouped up front for 1441 ** convenience. 1442 ** 1443 ** 2018-08-14: Ticket https://www.sqlite.org/src/info/908f001483982c43 1444 ** The order of constraints used to have OE_Update as (2) and OE_Abort 1445 ** and so forth as (1). But apparently PostgreSQL checks the OE_Update 1446 ** constraint before any others, so it had to be moved. 1447 ** 1448 ** Constraint checking code is generated in this order: 1449 ** (A) The rowid constraint 1450 ** (B) Unique index constraints that do not have OE_Replace as their 1451 ** default conflict resolution strategy 1452 ** (C) Unique index that do use OE_Replace by default. 1453 ** 1454 ** The ordering of (2) and (3) is accomplished by making sure the linked 1455 ** list of indexes attached to a table puts all OE_Replace indexes last 1456 ** in the list. See sqlite3CreateIndex() for where that happens. 1457 */ 1458 1459 if( pUpsert ){ 1460 if( pUpsert->pUpsertTarget==0 ){ 1461 /* An ON CONFLICT DO NOTHING clause, without a constraint-target. 1462 ** Make all unique constraint resolution be OE_Ignore */ 1463 assert( pUpsert->pUpsertSet==0 ); 1464 overrideError = OE_Ignore; 1465 pUpsert = 0; 1466 }else if( (pUpIdx = pUpsert->pUpsertIdx)!=0 ){ 1467 /* If the constraint-target uniqueness check must be run first. 1468 ** Jump to that uniqueness check now */ 1469 upsertJump = sqlite3VdbeAddOp0(v, OP_Goto); 1470 VdbeComment((v, "UPSERT constraint goes first")); 1471 } 1472 } 1473 1474 /* If rowid is changing, make sure the new rowid does not previously 1475 ** exist in the table. 1476 */ 1477 if( pkChng && pPk==0 ){ 1478 int addrRowidOk = sqlite3VdbeMakeLabel(pParse); 1479 1480 /* Figure out what action to take in case of a rowid collision */ 1481 onError = pTab->keyConf; 1482 if( overrideError!=OE_Default ){ 1483 onError = overrideError; 1484 }else if( onError==OE_Default ){ 1485 onError = OE_Abort; 1486 } 1487 1488 /* figure out whether or not upsert applies in this case */ 1489 if( pUpsert && pUpsert->pUpsertIdx==0 ){ 1490 if( pUpsert->pUpsertSet==0 ){ 1491 onError = OE_Ignore; /* DO NOTHING is the same as INSERT OR IGNORE */ 1492 }else{ 1493 onError = OE_Update; /* DO UPDATE */ 1494 } 1495 } 1496 1497 /* If the response to a rowid conflict is REPLACE but the response 1498 ** to some other UNIQUE constraint is FAIL or IGNORE, then we need 1499 ** to defer the running of the rowid conflict checking until after 1500 ** the UNIQUE constraints have run. 1501 */ 1502 if( onError==OE_Replace /* IPK rule is REPLACE */ 1503 && onError!=overrideError /* Rules for other contraints are different */ 1504 && pTab->pIndex /* There exist other constraints */ 1505 ){ 1506 ipkTop = sqlite3VdbeAddOp0(v, OP_Goto)+1; 1507 VdbeComment((v, "defer IPK REPLACE until last")); 1508 } 1509 1510 if( isUpdate ){ 1511 /* pkChng!=0 does not mean that the rowid has changed, only that 1512 ** it might have changed. Skip the conflict logic below if the rowid 1513 ** is unchanged. */ 1514 sqlite3VdbeAddOp3(v, OP_Eq, regNewData, addrRowidOk, regOldData); 1515 sqlite3VdbeChangeP5(v, SQLITE_NOTNULL); 1516 VdbeCoverage(v); 1517 } 1518 1519 /* Check to see if the new rowid already exists in the table. Skip 1520 ** the following conflict logic if it does not. */ 1521 VdbeNoopComment((v, "uniqueness check for ROWID")); 1522 sqlite3VdbeVerifyAbortable(v, onError); 1523 sqlite3VdbeAddOp3(v, OP_NotExists, iDataCur, addrRowidOk, regNewData); 1524 VdbeCoverage(v); 1525 1526 switch( onError ){ 1527 default: { 1528 onError = OE_Abort; 1529 /* Fall thru into the next case */ 1530 } 1531 case OE_Rollback: 1532 case OE_Abort: 1533 case OE_Fail: { 1534 testcase( onError==OE_Rollback ); 1535 testcase( onError==OE_Abort ); 1536 testcase( onError==OE_Fail ); 1537 sqlite3RowidConstraint(pParse, onError, pTab); 1538 break; 1539 } 1540 case OE_Replace: { 1541 /* If there are DELETE triggers on this table and the 1542 ** recursive-triggers flag is set, call GenerateRowDelete() to 1543 ** remove the conflicting row from the table. This will fire 1544 ** the triggers and remove both the table and index b-tree entries. 1545 ** 1546 ** Otherwise, if there are no triggers or the recursive-triggers 1547 ** flag is not set, but the table has one or more indexes, call 1548 ** GenerateRowIndexDelete(). This removes the index b-tree entries 1549 ** only. The table b-tree entry will be replaced by the new entry 1550 ** when it is inserted. 1551 ** 1552 ** If either GenerateRowDelete() or GenerateRowIndexDelete() is called, 1553 ** also invoke MultiWrite() to indicate that this VDBE may require 1554 ** statement rollback (if the statement is aborted after the delete 1555 ** takes place). Earlier versions called sqlite3MultiWrite() regardless, 1556 ** but being more selective here allows statements like: 1557 ** 1558 ** REPLACE INTO t(rowid) VALUES($newrowid) 1559 ** 1560 ** to run without a statement journal if there are no indexes on the 1561 ** table. 1562 */ 1563 Trigger *pTrigger = 0; 1564 if( db->flags&SQLITE_RecTriggers ){ 1565 pTrigger = sqlite3TriggersExist(pParse, pTab, TK_DELETE, 0, 0); 1566 } 1567 if( pTrigger || sqlite3FkRequired(pParse, pTab, 0, 0) ){ 1568 sqlite3MultiWrite(pParse); 1569 sqlite3GenerateRowDelete(pParse, pTab, pTrigger, iDataCur, iIdxCur, 1570 regNewData, 1, 0, OE_Replace, 1, -1); 1571 }else{ 1572 #ifdef SQLITE_ENABLE_PREUPDATE_HOOK 1573 assert( HasRowid(pTab) ); 1574 /* This OP_Delete opcode fires the pre-update-hook only. It does 1575 ** not modify the b-tree. It is more efficient to let the coming 1576 ** OP_Insert replace the existing entry than it is to delete the 1577 ** existing entry and then insert a new one. */ 1578 sqlite3VdbeAddOp2(v, OP_Delete, iDataCur, OPFLAG_ISNOOP); 1579 sqlite3VdbeAppendP4(v, pTab, P4_TABLE); 1580 #endif /* SQLITE_ENABLE_PREUPDATE_HOOK */ 1581 if( pTab->pIndex ){ 1582 sqlite3MultiWrite(pParse); 1583 sqlite3GenerateRowIndexDelete(pParse, pTab, iDataCur, iIdxCur,0,-1); 1584 } 1585 } 1586 seenReplace = 1; 1587 break; 1588 } 1589 #ifndef SQLITE_OMIT_UPSERT 1590 case OE_Update: { 1591 sqlite3UpsertDoUpdate(pParse, pUpsert, pTab, 0, iDataCur); 1592 /* Fall through */ 1593 } 1594 #endif 1595 case OE_Ignore: { 1596 testcase( onError==OE_Ignore ); 1597 sqlite3VdbeGoto(v, ignoreDest); 1598 break; 1599 } 1600 } 1601 sqlite3VdbeResolveLabel(v, addrRowidOk); 1602 if( ipkTop ){ 1603 ipkBottom = sqlite3VdbeAddOp0(v, OP_Goto); 1604 sqlite3VdbeJumpHere(v, ipkTop-1); 1605 } 1606 } 1607 1608 /* Test all UNIQUE constraints by creating entries for each UNIQUE 1609 ** index and making sure that duplicate entries do not already exist. 1610 ** Compute the revised record entries for indices as we go. 1611 ** 1612 ** This loop also handles the case of the PRIMARY KEY index for a 1613 ** WITHOUT ROWID table. 1614 */ 1615 for(ix=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, ix++){ 1616 int regIdx; /* Range of registers hold conent for pIdx */ 1617 int regR; /* Range of registers holding conflicting PK */ 1618 int iThisCur; /* Cursor for this UNIQUE index */ 1619 int addrUniqueOk; /* Jump here if the UNIQUE constraint is satisfied */ 1620 1621 if( aRegIdx[ix]==0 ) continue; /* Skip indices that do not change */ 1622 if( pUpIdx==pIdx ){ 1623 addrUniqueOk = upsertJump+1; 1624 upsertBypass = sqlite3VdbeGoto(v, 0); 1625 VdbeComment((v, "Skip upsert subroutine")); 1626 sqlite3VdbeJumpHere(v, upsertJump); 1627 }else{ 1628 addrUniqueOk = sqlite3VdbeMakeLabel(pParse); 1629 } 1630 if( bAffinityDone==0 && (pUpIdx==0 || pUpIdx==pIdx) ){ 1631 sqlite3TableAffinity(v, pTab, regNewData+1); 1632 bAffinityDone = 1; 1633 } 1634 VdbeNoopComment((v, "uniqueness check for %s", pIdx->zName)); 1635 iThisCur = iIdxCur+ix; 1636 1637 1638 /* Skip partial indices for which the WHERE clause is not true */ 1639 if( pIdx->pPartIdxWhere ){ 1640 sqlite3VdbeAddOp2(v, OP_Null, 0, aRegIdx[ix]); 1641 pParse->iSelfTab = -(regNewData+1); 1642 sqlite3ExprIfFalseDup(pParse, pIdx->pPartIdxWhere, addrUniqueOk, 1643 SQLITE_JUMPIFNULL); 1644 pParse->iSelfTab = 0; 1645 } 1646 1647 /* Create a record for this index entry as it should appear after 1648 ** the insert or update. Store that record in the aRegIdx[ix] register 1649 */ 1650 regIdx = aRegIdx[ix]+1; 1651 for(i=0; i<pIdx->nColumn; i++){ 1652 int iField = pIdx->aiColumn[i]; 1653 int x; 1654 if( iField==XN_EXPR ){ 1655 pParse->iSelfTab = -(regNewData+1); 1656 sqlite3ExprCodeCopy(pParse, pIdx->aColExpr->a[i].pExpr, regIdx+i); 1657 pParse->iSelfTab = 0; 1658 VdbeComment((v, "%s column %d", pIdx->zName, i)); 1659 }else{ 1660 if( iField==XN_ROWID || iField==pTab->iPKey ){ 1661 x = regNewData; 1662 }else{ 1663 x = iField + regNewData + 1; 1664 } 1665 sqlite3VdbeAddOp2(v, iField<0 ? OP_IntCopy : OP_SCopy, x, regIdx+i); 1666 VdbeComment((v, "%s", iField<0 ? "rowid" : pTab->aCol[iField].zName)); 1667 } 1668 } 1669 sqlite3VdbeAddOp3(v, OP_MakeRecord, regIdx, pIdx->nColumn, aRegIdx[ix]); 1670 VdbeComment((v, "for %s", pIdx->zName)); 1671 #ifdef SQLITE_ENABLE_NULL_TRIM 1672 if( pIdx->idxType==SQLITE_IDXTYPE_PRIMARYKEY ){ 1673 sqlite3SetMakeRecordP5(v, pIdx->pTable); 1674 } 1675 #endif 1676 1677 /* In an UPDATE operation, if this index is the PRIMARY KEY index 1678 ** of a WITHOUT ROWID table and there has been no change the 1679 ** primary key, then no collision is possible. The collision detection 1680 ** logic below can all be skipped. */ 1681 if( isUpdate && pPk==pIdx && pkChng==0 ){ 1682 sqlite3VdbeResolveLabel(v, addrUniqueOk); 1683 continue; 1684 } 1685 1686 /* Find out what action to take in case there is a uniqueness conflict */ 1687 onError = pIdx->onError; 1688 if( onError==OE_None ){ 1689 sqlite3VdbeResolveLabel(v, addrUniqueOk); 1690 continue; /* pIdx is not a UNIQUE index */ 1691 } 1692 if( overrideError!=OE_Default ){ 1693 onError = overrideError; 1694 }else if( onError==OE_Default ){ 1695 onError = OE_Abort; 1696 } 1697 1698 /* Figure out if the upsert clause applies to this index */ 1699 if( pUpIdx==pIdx ){ 1700 if( pUpsert->pUpsertSet==0 ){ 1701 onError = OE_Ignore; /* DO NOTHING is the same as INSERT OR IGNORE */ 1702 }else{ 1703 onError = OE_Update; /* DO UPDATE */ 1704 } 1705 } 1706 1707 /* Collision detection may be omitted if all of the following are true: 1708 ** (1) The conflict resolution algorithm is REPLACE 1709 ** (2) The table is a WITHOUT ROWID table 1710 ** (3) There are no secondary indexes on the table 1711 ** (4) No delete triggers need to be fired if there is a conflict 1712 ** (5) No FK constraint counters need to be updated if a conflict occurs. 1713 ** 1714 ** This is not possible for ENABLE_PREUPDATE_HOOK builds, as the row 1715 ** must be explicitly deleted in order to ensure any pre-update hook 1716 ** is invoked. */ 1717 #ifndef SQLITE_ENABLE_PREUPDATE_HOOK 1718 if( (ix==0 && pIdx->pNext==0) /* Condition 3 */ 1719 && pPk==pIdx /* Condition 2 */ 1720 && onError==OE_Replace /* Condition 1 */ 1721 && ( 0==(db->flags&SQLITE_RecTriggers) || /* Condition 4 */ 1722 0==sqlite3TriggersExist(pParse, pTab, TK_DELETE, 0, 0)) 1723 && ( 0==(db->flags&SQLITE_ForeignKeys) || /* Condition 5 */ 1724 (0==pTab->pFKey && 0==sqlite3FkReferences(pTab))) 1725 ){ 1726 sqlite3VdbeResolveLabel(v, addrUniqueOk); 1727 continue; 1728 } 1729 #endif /* ifndef SQLITE_ENABLE_PREUPDATE_HOOK */ 1730 1731 /* Check to see if the new index entry will be unique */ 1732 sqlite3VdbeVerifyAbortable(v, onError); 1733 sqlite3VdbeAddOp4Int(v, OP_NoConflict, iThisCur, addrUniqueOk, 1734 regIdx, pIdx->nKeyCol); VdbeCoverage(v); 1735 1736 /* Generate code to handle collisions */ 1737 regR = (pIdx==pPk) ? regIdx : sqlite3GetTempRange(pParse, nPkField); 1738 if( isUpdate || onError==OE_Replace ){ 1739 if( HasRowid(pTab) ){ 1740 sqlite3VdbeAddOp2(v, OP_IdxRowid, iThisCur, regR); 1741 /* Conflict only if the rowid of the existing index entry 1742 ** is different from old-rowid */ 1743 if( isUpdate ){ 1744 sqlite3VdbeAddOp3(v, OP_Eq, regR, addrUniqueOk, regOldData); 1745 sqlite3VdbeChangeP5(v, SQLITE_NOTNULL); 1746 VdbeCoverage(v); 1747 } 1748 }else{ 1749 int x; 1750 /* Extract the PRIMARY KEY from the end of the index entry and 1751 ** store it in registers regR..regR+nPk-1 */ 1752 if( pIdx!=pPk ){ 1753 for(i=0; i<pPk->nKeyCol; i++){ 1754 assert( pPk->aiColumn[i]>=0 ); 1755 x = sqlite3ColumnOfIndex(pIdx, pPk->aiColumn[i]); 1756 sqlite3VdbeAddOp3(v, OP_Column, iThisCur, x, regR+i); 1757 VdbeComment((v, "%s.%s", pTab->zName, 1758 pTab->aCol[pPk->aiColumn[i]].zName)); 1759 } 1760 } 1761 if( isUpdate ){ 1762 /* If currently processing the PRIMARY KEY of a WITHOUT ROWID 1763 ** table, only conflict if the new PRIMARY KEY values are actually 1764 ** different from the old. 1765 ** 1766 ** For a UNIQUE index, only conflict if the PRIMARY KEY values 1767 ** of the matched index row are different from the original PRIMARY 1768 ** KEY values of this row before the update. */ 1769 int addrJump = sqlite3VdbeCurrentAddr(v)+pPk->nKeyCol; 1770 int op = OP_Ne; 1771 int regCmp = (IsPrimaryKeyIndex(pIdx) ? regIdx : regR); 1772 1773 for(i=0; i<pPk->nKeyCol; i++){ 1774 char *p4 = (char*)sqlite3LocateCollSeq(pParse, pPk->azColl[i]); 1775 x = pPk->aiColumn[i]; 1776 assert( x>=0 ); 1777 if( i==(pPk->nKeyCol-1) ){ 1778 addrJump = addrUniqueOk; 1779 op = OP_Eq; 1780 } 1781 sqlite3VdbeAddOp4(v, op, 1782 regOldData+1+x, addrJump, regCmp+i, p4, P4_COLLSEQ 1783 ); 1784 sqlite3VdbeChangeP5(v, SQLITE_NOTNULL); 1785 VdbeCoverageIf(v, op==OP_Eq); 1786 VdbeCoverageIf(v, op==OP_Ne); 1787 } 1788 } 1789 } 1790 } 1791 1792 /* Generate code that executes if the new index entry is not unique */ 1793 assert( onError==OE_Rollback || onError==OE_Abort || onError==OE_Fail 1794 || onError==OE_Ignore || onError==OE_Replace || onError==OE_Update ); 1795 switch( onError ){ 1796 case OE_Rollback: 1797 case OE_Abort: 1798 case OE_Fail: { 1799 testcase( onError==OE_Rollback ); 1800 testcase( onError==OE_Abort ); 1801 testcase( onError==OE_Fail ); 1802 sqlite3UniqueConstraint(pParse, onError, pIdx); 1803 break; 1804 } 1805 #ifndef SQLITE_OMIT_UPSERT 1806 case OE_Update: { 1807 sqlite3UpsertDoUpdate(pParse, pUpsert, pTab, pIdx, iIdxCur+ix); 1808 /* Fall through */ 1809 } 1810 #endif 1811 case OE_Ignore: { 1812 testcase( onError==OE_Ignore ); 1813 sqlite3VdbeGoto(v, ignoreDest); 1814 break; 1815 } 1816 default: { 1817 Trigger *pTrigger = 0; 1818 assert( onError==OE_Replace ); 1819 if( db->flags&SQLITE_RecTriggers ){ 1820 pTrigger = sqlite3TriggersExist(pParse, pTab, TK_DELETE, 0, 0); 1821 } 1822 if( pTrigger || sqlite3FkRequired(pParse, pTab, 0, 0) ){ 1823 sqlite3MultiWrite(pParse); 1824 } 1825 sqlite3GenerateRowDelete(pParse, pTab, pTrigger, iDataCur, iIdxCur, 1826 regR, nPkField, 0, OE_Replace, 1827 (pIdx==pPk ? ONEPASS_SINGLE : ONEPASS_OFF), iThisCur); 1828 seenReplace = 1; 1829 break; 1830 } 1831 } 1832 if( pUpIdx==pIdx ){ 1833 sqlite3VdbeGoto(v, upsertJump+1); 1834 sqlite3VdbeJumpHere(v, upsertBypass); 1835 }else{ 1836 sqlite3VdbeResolveLabel(v, addrUniqueOk); 1837 } 1838 if( regR!=regIdx ) sqlite3ReleaseTempRange(pParse, regR, nPkField); 1839 } 1840 1841 /* If the IPK constraint is a REPLACE, run it last */ 1842 if( ipkTop ){ 1843 sqlite3VdbeGoto(v, ipkTop); 1844 VdbeComment((v, "Do IPK REPLACE")); 1845 sqlite3VdbeJumpHere(v, ipkBottom); 1846 } 1847 1848 *pbMayReplace = seenReplace; 1849 VdbeModuleComment((v, "END: GenCnstCks(%d)", seenReplace)); 1850 } 1851 1852 #ifdef SQLITE_ENABLE_NULL_TRIM 1853 /* 1854 ** Change the P5 operand on the last opcode (which should be an OP_MakeRecord) 1855 ** to be the number of columns in table pTab that must not be NULL-trimmed. 1856 ** 1857 ** Or if no columns of pTab may be NULL-trimmed, leave P5 at zero. 1858 */ 1859 void sqlite3SetMakeRecordP5(Vdbe *v, Table *pTab){ 1860 u16 i; 1861 1862 /* Records with omitted columns are only allowed for schema format 1863 ** version 2 and later (SQLite version 3.1.4, 2005-02-20). */ 1864 if( pTab->pSchema->file_format<2 ) return; 1865 1866 for(i=pTab->nCol-1; i>0; i--){ 1867 if( pTab->aCol[i].pDflt!=0 ) break; 1868 if( pTab->aCol[i].colFlags & COLFLAG_PRIMKEY ) break; 1869 } 1870 sqlite3VdbeChangeP5(v, i+1); 1871 } 1872 #endif 1873 1874 /* 1875 ** This routine generates code to finish the INSERT or UPDATE operation 1876 ** that was started by a prior call to sqlite3GenerateConstraintChecks. 1877 ** A consecutive range of registers starting at regNewData contains the 1878 ** rowid and the content to be inserted. 1879 ** 1880 ** The arguments to this routine should be the same as the first six 1881 ** arguments to sqlite3GenerateConstraintChecks. 1882 */ 1883 void sqlite3CompleteInsertion( 1884 Parse *pParse, /* The parser context */ 1885 Table *pTab, /* the table into which we are inserting */ 1886 int iDataCur, /* Cursor of the canonical data source */ 1887 int iIdxCur, /* First index cursor */ 1888 int regNewData, /* Range of content */ 1889 int *aRegIdx, /* Register used by each index. 0 for unused indices */ 1890 int update_flags, /* True for UPDATE, False for INSERT */ 1891 int appendBias, /* True if this is likely to be an append */ 1892 int useSeekResult /* True to set the USESEEKRESULT flag on OP_[Idx]Insert */ 1893 ){ 1894 Vdbe *v; /* Prepared statements under construction */ 1895 Index *pIdx; /* An index being inserted or updated */ 1896 u8 pik_flags; /* flag values passed to the btree insert */ 1897 int regData; /* Content registers (after the rowid) */ 1898 int regRec; /* Register holding assembled record for the table */ 1899 int i; /* Loop counter */ 1900 u8 bAffinityDone = 0; /* True if OP_Affinity has been run already */ 1901 1902 assert( update_flags==0 1903 || update_flags==OPFLAG_ISUPDATE 1904 || update_flags==(OPFLAG_ISUPDATE|OPFLAG_SAVEPOSITION) 1905 ); 1906 1907 v = sqlite3GetVdbe(pParse); 1908 assert( v!=0 ); 1909 assert( pTab->pSelect==0 ); /* This table is not a VIEW */ 1910 for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){ 1911 if( aRegIdx[i]==0 ) continue; 1912 bAffinityDone = 1; 1913 if( pIdx->pPartIdxWhere ){ 1914 sqlite3VdbeAddOp2(v, OP_IsNull, aRegIdx[i], sqlite3VdbeCurrentAddr(v)+2); 1915 VdbeCoverage(v); 1916 } 1917 pik_flags = (useSeekResult ? OPFLAG_USESEEKRESULT : 0); 1918 if( IsPrimaryKeyIndex(pIdx) && !HasRowid(pTab) ){ 1919 assert( pParse->nested==0 ); 1920 pik_flags |= OPFLAG_NCHANGE; 1921 pik_flags |= (update_flags & OPFLAG_SAVEPOSITION); 1922 #ifdef SQLITE_ENABLE_PREUPDATE_HOOK 1923 if( update_flags==0 ){ 1924 int r = sqlite3GetTempReg(pParse); 1925 sqlite3VdbeAddOp2(v, OP_Integer, 0, r); 1926 sqlite3VdbeAddOp4(v, OP_Insert, 1927 iIdxCur+i, aRegIdx[i], r, (char*)pTab, P4_TABLE 1928 ); 1929 sqlite3VdbeChangeP5(v, OPFLAG_ISNOOP); 1930 sqlite3ReleaseTempReg(pParse, r); 1931 } 1932 #endif 1933 } 1934 sqlite3VdbeAddOp4Int(v, OP_IdxInsert, iIdxCur+i, aRegIdx[i], 1935 aRegIdx[i]+1, 1936 pIdx->uniqNotNull ? pIdx->nKeyCol: pIdx->nColumn); 1937 sqlite3VdbeChangeP5(v, pik_flags); 1938 } 1939 if( !HasRowid(pTab) ) return; 1940 regData = regNewData + 1; 1941 regRec = sqlite3GetTempReg(pParse); 1942 sqlite3VdbeAddOp3(v, OP_MakeRecord, regData, pTab->nCol, regRec); 1943 sqlite3SetMakeRecordP5(v, pTab); 1944 if( !bAffinityDone ){ 1945 sqlite3TableAffinity(v, pTab, 0); 1946 } 1947 if( pParse->nested ){ 1948 pik_flags = 0; 1949 }else{ 1950 pik_flags = OPFLAG_NCHANGE; 1951 pik_flags |= (update_flags?update_flags:OPFLAG_LASTROWID); 1952 } 1953 if( appendBias ){ 1954 pik_flags |= OPFLAG_APPEND; 1955 } 1956 if( useSeekResult ){ 1957 pik_flags |= OPFLAG_USESEEKRESULT; 1958 } 1959 sqlite3VdbeAddOp3(v, OP_Insert, iDataCur, regRec, regNewData); 1960 if( !pParse->nested ){ 1961 sqlite3VdbeAppendP4(v, pTab, P4_TABLE); 1962 } 1963 sqlite3VdbeChangeP5(v, pik_flags); 1964 } 1965 1966 /* 1967 ** Allocate cursors for the pTab table and all its indices and generate 1968 ** code to open and initialized those cursors. 1969 ** 1970 ** The cursor for the object that contains the complete data (normally 1971 ** the table itself, but the PRIMARY KEY index in the case of a WITHOUT 1972 ** ROWID table) is returned in *piDataCur. The first index cursor is 1973 ** returned in *piIdxCur. The number of indices is returned. 1974 ** 1975 ** Use iBase as the first cursor (either the *piDataCur for rowid tables 1976 ** or the first index for WITHOUT ROWID tables) if it is non-negative. 1977 ** If iBase is negative, then allocate the next available cursor. 1978 ** 1979 ** For a rowid table, *piDataCur will be exactly one less than *piIdxCur. 1980 ** For a WITHOUT ROWID table, *piDataCur will be somewhere in the range 1981 ** of *piIdxCurs, depending on where the PRIMARY KEY index appears on the 1982 ** pTab->pIndex list. 1983 ** 1984 ** If pTab is a virtual table, then this routine is a no-op and the 1985 ** *piDataCur and *piIdxCur values are left uninitialized. 1986 */ 1987 int sqlite3OpenTableAndIndices( 1988 Parse *pParse, /* Parsing context */ 1989 Table *pTab, /* Table to be opened */ 1990 int op, /* OP_OpenRead or OP_OpenWrite */ 1991 u8 p5, /* P5 value for OP_Open* opcodes (except on WITHOUT ROWID) */ 1992 int iBase, /* Use this for the table cursor, if there is one */ 1993 u8 *aToOpen, /* If not NULL: boolean for each table and index */ 1994 int *piDataCur, /* Write the database source cursor number here */ 1995 int *piIdxCur /* Write the first index cursor number here */ 1996 ){ 1997 int i; 1998 int iDb; 1999 int iDataCur; 2000 Index *pIdx; 2001 Vdbe *v; 2002 2003 assert( op==OP_OpenRead || op==OP_OpenWrite ); 2004 assert( op==OP_OpenWrite || p5==0 ); 2005 if( IsVirtual(pTab) ){ 2006 /* This routine is a no-op for virtual tables. Leave the output 2007 ** variables *piDataCur and *piIdxCur uninitialized so that valgrind 2008 ** can detect if they are used by mistake in the caller. */ 2009 return 0; 2010 } 2011 iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema); 2012 v = sqlite3GetVdbe(pParse); 2013 assert( v!=0 ); 2014 if( iBase<0 ) iBase = pParse->nTab; 2015 iDataCur = iBase++; 2016 if( piDataCur ) *piDataCur = iDataCur; 2017 if( HasRowid(pTab) && (aToOpen==0 || aToOpen[0]) ){ 2018 sqlite3OpenTable(pParse, iDataCur, iDb, pTab, op); 2019 }else{ 2020 sqlite3TableLock(pParse, iDb, pTab->tnum, op==OP_OpenWrite, pTab->zName); 2021 } 2022 if( piIdxCur ) *piIdxCur = iBase; 2023 for(i=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){ 2024 int iIdxCur = iBase++; 2025 assert( pIdx->pSchema==pTab->pSchema ); 2026 if( IsPrimaryKeyIndex(pIdx) && !HasRowid(pTab) ){ 2027 if( piDataCur ) *piDataCur = iIdxCur; 2028 p5 = 0; 2029 } 2030 if( aToOpen==0 || aToOpen[i+1] ){ 2031 sqlite3VdbeAddOp3(v, op, iIdxCur, pIdx->tnum, iDb); 2032 sqlite3VdbeSetP4KeyInfo(pParse, pIdx); 2033 sqlite3VdbeChangeP5(v, p5); 2034 VdbeComment((v, "%s", pIdx->zName)); 2035 } 2036 } 2037 if( iBase>pParse->nTab ) pParse->nTab = iBase; 2038 return i; 2039 } 2040 2041 2042 #ifdef SQLITE_TEST 2043 /* 2044 ** The following global variable is incremented whenever the 2045 ** transfer optimization is used. This is used for testing 2046 ** purposes only - to make sure the transfer optimization really 2047 ** is happening when it is supposed to. 2048 */ 2049 int sqlite3_xferopt_count; 2050 #endif /* SQLITE_TEST */ 2051 2052 2053 #ifndef SQLITE_OMIT_XFER_OPT 2054 /* 2055 ** Check to see if index pSrc is compatible as a source of data 2056 ** for index pDest in an insert transfer optimization. The rules 2057 ** for a compatible index: 2058 ** 2059 ** * The index is over the same set of columns 2060 ** * The same DESC and ASC markings occurs on all columns 2061 ** * The same onError processing (OE_Abort, OE_Ignore, etc) 2062 ** * The same collating sequence on each column 2063 ** * The index has the exact same WHERE clause 2064 */ 2065 static int xferCompatibleIndex(Index *pDest, Index *pSrc){ 2066 int i; 2067 assert( pDest && pSrc ); 2068 assert( pDest->pTable!=pSrc->pTable ); 2069 if( pDest->nKeyCol!=pSrc->nKeyCol ){ 2070 return 0; /* Different number of columns */ 2071 } 2072 if( pDest->onError!=pSrc->onError ){ 2073 return 0; /* Different conflict resolution strategies */ 2074 } 2075 for(i=0; i<pSrc->nKeyCol; i++){ 2076 if( pSrc->aiColumn[i]!=pDest->aiColumn[i] ){ 2077 return 0; /* Different columns indexed */ 2078 } 2079 if( pSrc->aiColumn[i]==XN_EXPR ){ 2080 assert( pSrc->aColExpr!=0 && pDest->aColExpr!=0 ); 2081 if( sqlite3ExprCompare(0, pSrc->aColExpr->a[i].pExpr, 2082 pDest->aColExpr->a[i].pExpr, -1)!=0 ){ 2083 return 0; /* Different expressions in the index */ 2084 } 2085 } 2086 if( pSrc->aSortOrder[i]!=pDest->aSortOrder[i] ){ 2087 return 0; /* Different sort orders */ 2088 } 2089 if( sqlite3_stricmp(pSrc->azColl[i],pDest->azColl[i])!=0 ){ 2090 return 0; /* Different collating sequences */ 2091 } 2092 } 2093 if( sqlite3ExprCompare(0, pSrc->pPartIdxWhere, pDest->pPartIdxWhere, -1) ){ 2094 return 0; /* Different WHERE clauses */ 2095 } 2096 2097 /* If no test above fails then the indices must be compatible */ 2098 return 1; 2099 } 2100 2101 /* 2102 ** Attempt the transfer optimization on INSERTs of the form 2103 ** 2104 ** INSERT INTO tab1 SELECT * FROM tab2; 2105 ** 2106 ** The xfer optimization transfers raw records from tab2 over to tab1. 2107 ** Columns are not decoded and reassembled, which greatly improves 2108 ** performance. Raw index records are transferred in the same way. 2109 ** 2110 ** The xfer optimization is only attempted if tab1 and tab2 are compatible. 2111 ** There are lots of rules for determining compatibility - see comments 2112 ** embedded in the code for details. 2113 ** 2114 ** This routine returns TRUE if the optimization is guaranteed to be used. 2115 ** Sometimes the xfer optimization will only work if the destination table 2116 ** is empty - a factor that can only be determined at run-time. In that 2117 ** case, this routine generates code for the xfer optimization but also 2118 ** does a test to see if the destination table is empty and jumps over the 2119 ** xfer optimization code if the test fails. In that case, this routine 2120 ** returns FALSE so that the caller will know to go ahead and generate 2121 ** an unoptimized transfer. This routine also returns FALSE if there 2122 ** is no chance that the xfer optimization can be applied. 2123 ** 2124 ** This optimization is particularly useful at making VACUUM run faster. 2125 */ 2126 static int xferOptimization( 2127 Parse *pParse, /* Parser context */ 2128 Table *pDest, /* The table we are inserting into */ 2129 Select *pSelect, /* A SELECT statement to use as the data source */ 2130 int onError, /* How to handle constraint errors */ 2131 int iDbDest /* The database of pDest */ 2132 ){ 2133 sqlite3 *db = pParse->db; 2134 ExprList *pEList; /* The result set of the SELECT */ 2135 Table *pSrc; /* The table in the FROM clause of SELECT */ 2136 Index *pSrcIdx, *pDestIdx; /* Source and destination indices */ 2137 struct SrcList_item *pItem; /* An element of pSelect->pSrc */ 2138 int i; /* Loop counter */ 2139 int iDbSrc; /* The database of pSrc */ 2140 int iSrc, iDest; /* Cursors from source and destination */ 2141 int addr1, addr2; /* Loop addresses */ 2142 int emptyDestTest = 0; /* Address of test for empty pDest */ 2143 int emptySrcTest = 0; /* Address of test for empty pSrc */ 2144 Vdbe *v; /* The VDBE we are building */ 2145 int regAutoinc; /* Memory register used by AUTOINC */ 2146 int destHasUniqueIdx = 0; /* True if pDest has a UNIQUE index */ 2147 int regData, regRowid; /* Registers holding data and rowid */ 2148 2149 if( pSelect==0 ){ 2150 return 0; /* Must be of the form INSERT INTO ... SELECT ... */ 2151 } 2152 if( pParse->pWith || pSelect->pWith ){ 2153 /* Do not attempt to process this query if there are an WITH clauses 2154 ** attached to it. Proceeding may generate a false "no such table: xxx" 2155 ** error if pSelect reads from a CTE named "xxx". */ 2156 return 0; 2157 } 2158 if( sqlite3TriggerList(pParse, pDest) ){ 2159 return 0; /* tab1 must not have triggers */ 2160 } 2161 #ifndef SQLITE_OMIT_VIRTUALTABLE 2162 if( IsVirtual(pDest) ){ 2163 return 0; /* tab1 must not be a virtual table */ 2164 } 2165 #endif 2166 if( onError==OE_Default ){ 2167 if( pDest->iPKey>=0 ) onError = pDest->keyConf; 2168 if( onError==OE_Default ) onError = OE_Abort; 2169 } 2170 assert(pSelect->pSrc); /* allocated even if there is no FROM clause */ 2171 if( pSelect->pSrc->nSrc!=1 ){ 2172 return 0; /* FROM clause must have exactly one term */ 2173 } 2174 if( pSelect->pSrc->a[0].pSelect ){ 2175 return 0; /* FROM clause cannot contain a subquery */ 2176 } 2177 if( pSelect->pWhere ){ 2178 return 0; /* SELECT may not have a WHERE clause */ 2179 } 2180 if( pSelect->pOrderBy ){ 2181 return 0; /* SELECT may not have an ORDER BY clause */ 2182 } 2183 /* Do not need to test for a HAVING clause. If HAVING is present but 2184 ** there is no ORDER BY, we will get an error. */ 2185 if( pSelect->pGroupBy ){ 2186 return 0; /* SELECT may not have a GROUP BY clause */ 2187 } 2188 if( pSelect->pLimit ){ 2189 return 0; /* SELECT may not have a LIMIT clause */ 2190 } 2191 if( pSelect->pPrior ){ 2192 return 0; /* SELECT may not be a compound query */ 2193 } 2194 if( pSelect->selFlags & SF_Distinct ){ 2195 return 0; /* SELECT may not be DISTINCT */ 2196 } 2197 pEList = pSelect->pEList; 2198 assert( pEList!=0 ); 2199 if( pEList->nExpr!=1 ){ 2200 return 0; /* The result set must have exactly one column */ 2201 } 2202 assert( pEList->a[0].pExpr ); 2203 if( pEList->a[0].pExpr->op!=TK_ASTERISK ){ 2204 return 0; /* The result set must be the special operator "*" */ 2205 } 2206 2207 /* At this point we have established that the statement is of the 2208 ** correct syntactic form to participate in this optimization. Now 2209 ** we have to check the semantics. 2210 */ 2211 pItem = pSelect->pSrc->a; 2212 pSrc = sqlite3LocateTableItem(pParse, 0, pItem); 2213 if( pSrc==0 ){ 2214 return 0; /* FROM clause does not contain a real table */ 2215 } 2216 if( pSrc->tnum==pDest->tnum && pSrc->pSchema==pDest->pSchema ){ 2217 testcase( pSrc!=pDest ); /* Possible due to bad sqlite_master.rootpage */ 2218 return 0; /* tab1 and tab2 may not be the same table */ 2219 } 2220 if( HasRowid(pDest)!=HasRowid(pSrc) ){ 2221 return 0; /* source and destination must both be WITHOUT ROWID or not */ 2222 } 2223 #ifndef SQLITE_OMIT_VIRTUALTABLE 2224 if( IsVirtual(pSrc) ){ 2225 return 0; /* tab2 must not be a virtual table */ 2226 } 2227 #endif 2228 if( pSrc->pSelect ){ 2229 return 0; /* tab2 may not be a view */ 2230 } 2231 if( pDest->nCol!=pSrc->nCol ){ 2232 return 0; /* Number of columns must be the same in tab1 and tab2 */ 2233 } 2234 if( pDest->iPKey!=pSrc->iPKey ){ 2235 return 0; /* Both tables must have the same INTEGER PRIMARY KEY */ 2236 } 2237 for(i=0; i<pDest->nCol; i++){ 2238 Column *pDestCol = &pDest->aCol[i]; 2239 Column *pSrcCol = &pSrc->aCol[i]; 2240 #ifdef SQLITE_ENABLE_HIDDEN_COLUMNS 2241 if( (db->mDbFlags & DBFLAG_Vacuum)==0 2242 && (pDestCol->colFlags | pSrcCol->colFlags) & COLFLAG_HIDDEN 2243 ){ 2244 return 0; /* Neither table may have __hidden__ columns */ 2245 } 2246 #endif 2247 if( pDestCol->affinity!=pSrcCol->affinity ){ 2248 return 0; /* Affinity must be the same on all columns */ 2249 } 2250 if( sqlite3_stricmp(pDestCol->zColl, pSrcCol->zColl)!=0 ){ 2251 return 0; /* Collating sequence must be the same on all columns */ 2252 } 2253 if( pDestCol->notNull && !pSrcCol->notNull ){ 2254 return 0; /* tab2 must be NOT NULL if tab1 is */ 2255 } 2256 /* Default values for second and subsequent columns need to match. */ 2257 if( i>0 ){ 2258 assert( pDestCol->pDflt==0 || pDestCol->pDflt->op==TK_SPAN ); 2259 assert( pSrcCol->pDflt==0 || pSrcCol->pDflt->op==TK_SPAN ); 2260 if( (pDestCol->pDflt==0)!=(pSrcCol->pDflt==0) 2261 || (pDestCol->pDflt && strcmp(pDestCol->pDflt->u.zToken, 2262 pSrcCol->pDflt->u.zToken)!=0) 2263 ){ 2264 return 0; /* Default values must be the same for all columns */ 2265 } 2266 } 2267 } 2268 for(pDestIdx=pDest->pIndex; pDestIdx; pDestIdx=pDestIdx->pNext){ 2269 if( IsUniqueIndex(pDestIdx) ){ 2270 destHasUniqueIdx = 1; 2271 } 2272 for(pSrcIdx=pSrc->pIndex; pSrcIdx; pSrcIdx=pSrcIdx->pNext){ 2273 if( xferCompatibleIndex(pDestIdx, pSrcIdx) ) break; 2274 } 2275 if( pSrcIdx==0 ){ 2276 return 0; /* pDestIdx has no corresponding index in pSrc */ 2277 } 2278 } 2279 #ifndef SQLITE_OMIT_CHECK 2280 if( pDest->pCheck && sqlite3ExprListCompare(pSrc->pCheck,pDest->pCheck,-1) ){ 2281 return 0; /* Tables have different CHECK constraints. Ticket #2252 */ 2282 } 2283 #endif 2284 #ifndef SQLITE_OMIT_FOREIGN_KEY 2285 /* Disallow the transfer optimization if the destination table constains 2286 ** any foreign key constraints. This is more restrictive than necessary. 2287 ** But the main beneficiary of the transfer optimization is the VACUUM 2288 ** command, and the VACUUM command disables foreign key constraints. So 2289 ** the extra complication to make this rule less restrictive is probably 2290 ** not worth the effort. Ticket [6284df89debdfa61db8073e062908af0c9b6118e] 2291 */ 2292 if( (db->flags & SQLITE_ForeignKeys)!=0 && pDest->pFKey!=0 ){ 2293 return 0; 2294 } 2295 #endif 2296 if( (db->flags & SQLITE_CountRows)!=0 ){ 2297 return 0; /* xfer opt does not play well with PRAGMA count_changes */ 2298 } 2299 2300 /* If we get this far, it means that the xfer optimization is at 2301 ** least a possibility, though it might only work if the destination 2302 ** table (tab1) is initially empty. 2303 */ 2304 #ifdef SQLITE_TEST 2305 sqlite3_xferopt_count++; 2306 #endif 2307 iDbSrc = sqlite3SchemaToIndex(db, pSrc->pSchema); 2308 v = sqlite3GetVdbe(pParse); 2309 sqlite3CodeVerifySchema(pParse, iDbSrc); 2310 iSrc = pParse->nTab++; 2311 iDest = pParse->nTab++; 2312 regAutoinc = autoIncBegin(pParse, iDbDest, pDest); 2313 regData = sqlite3GetTempReg(pParse); 2314 regRowid = sqlite3GetTempReg(pParse); 2315 sqlite3OpenTable(pParse, iDest, iDbDest, pDest, OP_OpenWrite); 2316 assert( HasRowid(pDest) || destHasUniqueIdx ); 2317 if( (db->mDbFlags & DBFLAG_Vacuum)==0 && ( 2318 (pDest->iPKey<0 && pDest->pIndex!=0) /* (1) */ 2319 || destHasUniqueIdx /* (2) */ 2320 || (onError!=OE_Abort && onError!=OE_Rollback) /* (3) */ 2321 )){ 2322 /* In some circumstances, we are able to run the xfer optimization 2323 ** only if the destination table is initially empty. Unless the 2324 ** DBFLAG_Vacuum flag is set, this block generates code to make 2325 ** that determination. If DBFLAG_Vacuum is set, then the destination 2326 ** table is always empty. 2327 ** 2328 ** Conditions under which the destination must be empty: 2329 ** 2330 ** (1) There is no INTEGER PRIMARY KEY but there are indices. 2331 ** (If the destination is not initially empty, the rowid fields 2332 ** of index entries might need to change.) 2333 ** 2334 ** (2) The destination has a unique index. (The xfer optimization 2335 ** is unable to test uniqueness.) 2336 ** 2337 ** (3) onError is something other than OE_Abort and OE_Rollback. 2338 */ 2339 addr1 = sqlite3VdbeAddOp2(v, OP_Rewind, iDest, 0); VdbeCoverage(v); 2340 emptyDestTest = sqlite3VdbeAddOp0(v, OP_Goto); 2341 sqlite3VdbeJumpHere(v, addr1); 2342 } 2343 if( HasRowid(pSrc) ){ 2344 u8 insFlags; 2345 sqlite3OpenTable(pParse, iSrc, iDbSrc, pSrc, OP_OpenRead); 2346 emptySrcTest = sqlite3VdbeAddOp2(v, OP_Rewind, iSrc, 0); VdbeCoverage(v); 2347 if( pDest->iPKey>=0 ){ 2348 addr1 = sqlite3VdbeAddOp2(v, OP_Rowid, iSrc, regRowid); 2349 sqlite3VdbeVerifyAbortable(v, onError); 2350 addr2 = sqlite3VdbeAddOp3(v, OP_NotExists, iDest, 0, regRowid); 2351 VdbeCoverage(v); 2352 sqlite3RowidConstraint(pParse, onError, pDest); 2353 sqlite3VdbeJumpHere(v, addr2); 2354 autoIncStep(pParse, regAutoinc, regRowid); 2355 }else if( pDest->pIndex==0 && !(db->mDbFlags & DBFLAG_Vacuum) ){ 2356 addr1 = sqlite3VdbeAddOp2(v, OP_NewRowid, iDest, regRowid); 2357 }else{ 2358 addr1 = sqlite3VdbeAddOp2(v, OP_Rowid, iSrc, regRowid); 2359 assert( (pDest->tabFlags & TF_Autoincrement)==0 ); 2360 } 2361 sqlite3VdbeAddOp3(v, OP_RowData, iSrc, regData, 1); 2362 if( db->mDbFlags & DBFLAG_Vacuum ){ 2363 sqlite3VdbeAddOp1(v, OP_SeekEnd, iDest); 2364 insFlags = OPFLAG_NCHANGE|OPFLAG_LASTROWID| 2365 OPFLAG_APPEND|OPFLAG_USESEEKRESULT; 2366 }else{ 2367 insFlags = OPFLAG_NCHANGE|OPFLAG_LASTROWID|OPFLAG_APPEND; 2368 } 2369 sqlite3VdbeAddOp4(v, OP_Insert, iDest, regData, regRowid, 2370 (char*)pDest, P4_TABLE); 2371 sqlite3VdbeChangeP5(v, insFlags); 2372 sqlite3VdbeAddOp2(v, OP_Next, iSrc, addr1); VdbeCoverage(v); 2373 sqlite3VdbeAddOp2(v, OP_Close, iSrc, 0); 2374 sqlite3VdbeAddOp2(v, OP_Close, iDest, 0); 2375 }else{ 2376 sqlite3TableLock(pParse, iDbDest, pDest->tnum, 1, pDest->zName); 2377 sqlite3TableLock(pParse, iDbSrc, pSrc->tnum, 0, pSrc->zName); 2378 } 2379 for(pDestIdx=pDest->pIndex; pDestIdx; pDestIdx=pDestIdx->pNext){ 2380 u8 idxInsFlags = 0; 2381 for(pSrcIdx=pSrc->pIndex; ALWAYS(pSrcIdx); pSrcIdx=pSrcIdx->pNext){ 2382 if( xferCompatibleIndex(pDestIdx, pSrcIdx) ) break; 2383 } 2384 assert( pSrcIdx ); 2385 sqlite3VdbeAddOp3(v, OP_OpenRead, iSrc, pSrcIdx->tnum, iDbSrc); 2386 sqlite3VdbeSetP4KeyInfo(pParse, pSrcIdx); 2387 VdbeComment((v, "%s", pSrcIdx->zName)); 2388 sqlite3VdbeAddOp3(v, OP_OpenWrite, iDest, pDestIdx->tnum, iDbDest); 2389 sqlite3VdbeSetP4KeyInfo(pParse, pDestIdx); 2390 sqlite3VdbeChangeP5(v, OPFLAG_BULKCSR); 2391 VdbeComment((v, "%s", pDestIdx->zName)); 2392 addr1 = sqlite3VdbeAddOp2(v, OP_Rewind, iSrc, 0); VdbeCoverage(v); 2393 sqlite3VdbeAddOp3(v, OP_RowData, iSrc, regData, 1); 2394 if( db->mDbFlags & DBFLAG_Vacuum ){ 2395 /* This INSERT command is part of a VACUUM operation, which guarantees 2396 ** that the destination table is empty. If all indexed columns use 2397 ** collation sequence BINARY, then it can also be assumed that the 2398 ** index will be populated by inserting keys in strictly sorted 2399 ** order. In this case, instead of seeking within the b-tree as part 2400 ** of every OP_IdxInsert opcode, an OP_SeekEnd is added before the 2401 ** OP_IdxInsert to seek to the point within the b-tree where each key 2402 ** should be inserted. This is faster. 2403 ** 2404 ** If any of the indexed columns use a collation sequence other than 2405 ** BINARY, this optimization is disabled. This is because the user 2406 ** might change the definition of a collation sequence and then run 2407 ** a VACUUM command. In that case keys may not be written in strictly 2408 ** sorted order. */ 2409 for(i=0; i<pSrcIdx->nColumn; i++){ 2410 const char *zColl = pSrcIdx->azColl[i]; 2411 if( sqlite3_stricmp(sqlite3StrBINARY, zColl) ) break; 2412 } 2413 if( i==pSrcIdx->nColumn ){ 2414 idxInsFlags = OPFLAG_USESEEKRESULT; 2415 sqlite3VdbeAddOp1(v, OP_SeekEnd, iDest); 2416 } 2417 } 2418 if( !HasRowid(pSrc) && pDestIdx->idxType==SQLITE_IDXTYPE_PRIMARYKEY ){ 2419 idxInsFlags |= OPFLAG_NCHANGE; 2420 } 2421 sqlite3VdbeAddOp2(v, OP_IdxInsert, iDest, regData); 2422 sqlite3VdbeChangeP5(v, idxInsFlags|OPFLAG_APPEND); 2423 sqlite3VdbeAddOp2(v, OP_Next, iSrc, addr1+1); VdbeCoverage(v); 2424 sqlite3VdbeJumpHere(v, addr1); 2425 sqlite3VdbeAddOp2(v, OP_Close, iSrc, 0); 2426 sqlite3VdbeAddOp2(v, OP_Close, iDest, 0); 2427 } 2428 if( emptySrcTest ) sqlite3VdbeJumpHere(v, emptySrcTest); 2429 sqlite3ReleaseTempReg(pParse, regRowid); 2430 sqlite3ReleaseTempReg(pParse, regData); 2431 if( emptyDestTest ){ 2432 sqlite3AutoincrementEnd(pParse); 2433 sqlite3VdbeAddOp2(v, OP_Halt, SQLITE_OK, 0); 2434 sqlite3VdbeJumpHere(v, emptyDestTest); 2435 sqlite3VdbeAddOp2(v, OP_Close, iDest, 0); 2436 return 0; 2437 }else{ 2438 return 1; 2439 } 2440 } 2441 #endif /* SQLITE_OMIT_XFER_OPT */ 2442