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 open a table for reading. 19 */ 20 void sqlite3OpenTable( 21 Parse *p, /* Generate code into this VDBE */ 22 int iCur, /* The cursor number of the table */ 23 int iDb, /* The database index in sqlite3.aDb[] */ 24 Table *pTab, /* The table to be opened */ 25 int opcode /* OP_OpenRead or OP_OpenWrite */ 26 ){ 27 Vdbe *v; 28 if( IsVirtual(pTab) ) return; 29 v = sqlite3GetVdbe(p); 30 assert( opcode==OP_OpenWrite || opcode==OP_OpenRead ); 31 sqlite3TableLock(p, iDb, pTab->tnum, (opcode==OP_OpenWrite)?1:0, pTab->zName); 32 sqlite3VdbeAddOp3(v, opcode, iCur, pTab->tnum, iDb); 33 sqlite3VdbeChangeP4(v, -1, SQLITE_INT_TO_PTR(pTab->nCol), P4_INT32); 34 VdbeComment((v, "%s", pTab->zName)); 35 } 36 37 /* 38 ** Return a pointer to the column affinity string associated with index 39 ** pIdx. A column affinity string has one character for each column in 40 ** the table, according to the affinity of the column: 41 ** 42 ** Character Column affinity 43 ** ------------------------------ 44 ** 'a' TEXT 45 ** 'b' NONE 46 ** 'c' NUMERIC 47 ** 'd' INTEGER 48 ** 'e' REAL 49 ** 50 ** An extra 'd' is appended to the end of the string to cover the 51 ** rowid that appears as the last column in every index. 52 ** 53 ** Memory for the buffer containing the column index affinity string 54 ** is managed along with the rest of the Index structure. It will be 55 ** released when sqlite3DeleteIndex() is called. 56 */ 57 const char *sqlite3IndexAffinityStr(Vdbe *v, Index *pIdx){ 58 if( !pIdx->zColAff ){ 59 /* The first time a column affinity string for a particular index is 60 ** required, it is allocated and populated here. It is then stored as 61 ** a member of the Index structure for subsequent use. 62 ** 63 ** The column affinity string will eventually be deleted by 64 ** sqliteDeleteIndex() when the Index structure itself is cleaned 65 ** up. 66 */ 67 int n; 68 Table *pTab = pIdx->pTable; 69 sqlite3 *db = sqlite3VdbeDb(v); 70 pIdx->zColAff = (char *)sqlite3DbMallocRaw(0, pIdx->nColumn+2); 71 if( !pIdx->zColAff ){ 72 db->mallocFailed = 1; 73 return 0; 74 } 75 for(n=0; n<pIdx->nColumn; n++){ 76 pIdx->zColAff[n] = pTab->aCol[pIdx->aiColumn[n]].affinity; 77 } 78 pIdx->zColAff[n++] = SQLITE_AFF_INTEGER; 79 pIdx->zColAff[n] = 0; 80 } 81 82 return pIdx->zColAff; 83 } 84 85 /* 86 ** Set P4 of the most recently inserted opcode to a column affinity 87 ** string for table pTab. A column affinity string has one character 88 ** for each column indexed by the index, according to the affinity of the 89 ** column: 90 ** 91 ** Character Column affinity 92 ** ------------------------------ 93 ** 'a' TEXT 94 ** 'b' NONE 95 ** 'c' NUMERIC 96 ** 'd' INTEGER 97 ** 'e' REAL 98 */ 99 void sqlite3TableAffinityStr(Vdbe *v, Table *pTab){ 100 /* The first time a column affinity string for a particular table 101 ** is required, it is allocated and populated here. It is then 102 ** stored as a member of the Table structure for subsequent use. 103 ** 104 ** The column affinity string will eventually be deleted by 105 ** sqlite3DeleteTable() when the Table structure itself is cleaned up. 106 */ 107 if( !pTab->zColAff ){ 108 char *zColAff; 109 int i; 110 sqlite3 *db = sqlite3VdbeDb(v); 111 112 zColAff = (char *)sqlite3DbMallocRaw(0, pTab->nCol+1); 113 if( !zColAff ){ 114 db->mallocFailed = 1; 115 return; 116 } 117 118 for(i=0; i<pTab->nCol; i++){ 119 zColAff[i] = pTab->aCol[i].affinity; 120 } 121 zColAff[pTab->nCol] = '\0'; 122 123 pTab->zColAff = zColAff; 124 } 125 126 sqlite3VdbeChangeP4(v, -1, pTab->zColAff, P4_TRANSIENT); 127 } 128 129 /* 130 ** Return non-zero if the table pTab in database iDb or any of its indices 131 ** have been opened at any point in the VDBE program beginning at location 132 ** iStartAddr throught the end of the program. This is used to see if 133 ** a statement of the form "INSERT INTO <iDb, pTab> SELECT ..." can 134 ** run without using temporary table for the results of the SELECT. 135 */ 136 static int readsTable(Parse *p, int iStartAddr, int iDb, Table *pTab){ 137 Vdbe *v = sqlite3GetVdbe(p); 138 int i; 139 int iEnd = sqlite3VdbeCurrentAddr(v); 140 #ifndef SQLITE_OMIT_VIRTUALTABLE 141 VTable *pVTab = IsVirtual(pTab) ? sqlite3GetVTable(p->db, pTab) : 0; 142 #endif 143 144 for(i=iStartAddr; i<iEnd; i++){ 145 VdbeOp *pOp = sqlite3VdbeGetOp(v, i); 146 assert( pOp!=0 ); 147 if( pOp->opcode==OP_OpenRead && pOp->p3==iDb ){ 148 Index *pIndex; 149 int tnum = pOp->p2; 150 if( tnum==pTab->tnum ){ 151 return 1; 152 } 153 for(pIndex=pTab->pIndex; pIndex; pIndex=pIndex->pNext){ 154 if( tnum==pIndex->tnum ){ 155 return 1; 156 } 157 } 158 } 159 #ifndef SQLITE_OMIT_VIRTUALTABLE 160 if( pOp->opcode==OP_VOpen && pOp->p4.pVtab==pVTab ){ 161 assert( pOp->p4.pVtab!=0 ); 162 assert( pOp->p4type==P4_VTAB ); 163 return 1; 164 } 165 #endif 166 } 167 return 0; 168 } 169 170 #ifndef SQLITE_OMIT_AUTOINCREMENT 171 /* 172 ** Locate or create an AutoincInfo structure associated with table pTab 173 ** which is in database iDb. Return the register number for the register 174 ** that holds the maximum rowid. 175 ** 176 ** There is at most one AutoincInfo structure per table even if the 177 ** same table is autoincremented multiple times due to inserts within 178 ** triggers. A new AutoincInfo structure is created if this is the 179 ** first use of table pTab. On 2nd and subsequent uses, the original 180 ** AutoincInfo structure is used. 181 ** 182 ** Three memory locations are allocated: 183 ** 184 ** (1) Register to hold the name of the pTab table. 185 ** (2) Register to hold the maximum ROWID of pTab. 186 ** (3) Register to hold the rowid in sqlite_sequence of pTab 187 ** 188 ** The 2nd register is the one that is returned. That is all the 189 ** insert routine needs to know about. 190 */ 191 static int autoIncBegin( 192 Parse *pParse, /* Parsing context */ 193 int iDb, /* Index of the database holding pTab */ 194 Table *pTab /* The table we are writing to */ 195 ){ 196 int memId = 0; /* Register holding maximum rowid */ 197 if( pTab->tabFlags & TF_Autoincrement ){ 198 Parse *pToplevel = sqlite3ParseToplevel(pParse); 199 AutoincInfo *pInfo; 200 201 pInfo = pToplevel->pAinc; 202 while( pInfo && pInfo->pTab!=pTab ){ pInfo = pInfo->pNext; } 203 if( pInfo==0 ){ 204 pInfo = sqlite3DbMallocRaw(pParse->db, sizeof(*pInfo)); 205 if( pInfo==0 ) return 0; 206 pInfo->pNext = pToplevel->pAinc; 207 pToplevel->pAinc = pInfo; 208 pInfo->pTab = pTab; 209 pInfo->iDb = iDb; 210 pToplevel->nMem++; /* Register to hold name of table */ 211 pInfo->regCtr = ++pToplevel->nMem; /* Max rowid register */ 212 pToplevel->nMem++; /* Rowid in sqlite_sequence */ 213 } 214 memId = pInfo->regCtr; 215 } 216 return memId; 217 } 218 219 /* 220 ** This routine generates code that will initialize all of the 221 ** register used by the autoincrement tracker. 222 */ 223 void sqlite3AutoincrementBegin(Parse *pParse){ 224 AutoincInfo *p; /* Information about an AUTOINCREMENT */ 225 sqlite3 *db = pParse->db; /* The database connection */ 226 Db *pDb; /* Database only autoinc table */ 227 int memId; /* Register holding max rowid */ 228 int addr; /* A VDBE address */ 229 Vdbe *v = pParse->pVdbe; /* VDBE under construction */ 230 231 /* This routine is never called during trigger-generation. It is 232 ** only called from the top-level */ 233 assert( pParse->pTriggerTab==0 ); 234 assert( pParse==sqlite3ParseToplevel(pParse) ); 235 236 assert( v ); /* We failed long ago if this is not so */ 237 for(p = pParse->pAinc; p; p = p->pNext){ 238 pDb = &db->aDb[p->iDb]; 239 memId = p->regCtr; 240 assert( sqlite3SchemaMutexHeld(db, 0, pDb->pSchema) ); 241 sqlite3OpenTable(pParse, 0, p->iDb, pDb->pSchema->pSeqTab, OP_OpenRead); 242 sqlite3VdbeAddOp3(v, OP_Null, 0, memId, memId+1); 243 addr = sqlite3VdbeCurrentAddr(v); 244 sqlite3VdbeAddOp4(v, OP_String8, 0, memId-1, 0, p->pTab->zName, 0); 245 sqlite3VdbeAddOp2(v, OP_Rewind, 0, addr+9); 246 sqlite3VdbeAddOp3(v, OP_Column, 0, 0, memId); 247 sqlite3VdbeAddOp3(v, OP_Ne, memId-1, addr+7, memId); 248 sqlite3VdbeChangeP5(v, SQLITE_JUMPIFNULL); 249 sqlite3VdbeAddOp2(v, OP_Rowid, 0, memId+1); 250 sqlite3VdbeAddOp3(v, OP_Column, 0, 1, memId); 251 sqlite3VdbeAddOp2(v, OP_Goto, 0, addr+9); 252 sqlite3VdbeAddOp2(v, OP_Next, 0, addr+2); 253 sqlite3VdbeAddOp2(v, OP_Integer, 0, memId); 254 sqlite3VdbeAddOp0(v, OP_Close); 255 } 256 } 257 258 /* 259 ** Update the maximum rowid for an autoincrement calculation. 260 ** 261 ** This routine should be called when the top of the stack holds a 262 ** new rowid that is about to be inserted. If that new rowid is 263 ** larger than the maximum rowid in the memId memory cell, then the 264 ** memory cell is updated. The stack is unchanged. 265 */ 266 static void autoIncStep(Parse *pParse, int memId, int regRowid){ 267 if( memId>0 ){ 268 sqlite3VdbeAddOp2(pParse->pVdbe, OP_MemMax, memId, regRowid); 269 } 270 } 271 272 /* 273 ** This routine generates the code needed to write autoincrement 274 ** maximum rowid values back into the sqlite_sequence register. 275 ** Every statement that might do an INSERT into an autoincrement 276 ** table (either directly or through triggers) needs to call this 277 ** routine just before the "exit" code. 278 */ 279 void sqlite3AutoincrementEnd(Parse *pParse){ 280 AutoincInfo *p; 281 Vdbe *v = pParse->pVdbe; 282 sqlite3 *db = pParse->db; 283 284 assert( v ); 285 for(p = pParse->pAinc; p; p = p->pNext){ 286 Db *pDb = &db->aDb[p->iDb]; 287 int j1, j2, j3, j4, j5; 288 int iRec; 289 int memId = p->regCtr; 290 291 iRec = sqlite3GetTempReg(pParse); 292 assert( sqlite3SchemaMutexHeld(db, 0, pDb->pSchema) ); 293 sqlite3OpenTable(pParse, 0, p->iDb, pDb->pSchema->pSeqTab, OP_OpenWrite); 294 j1 = sqlite3VdbeAddOp1(v, OP_NotNull, memId+1); 295 j2 = sqlite3VdbeAddOp0(v, OP_Rewind); 296 j3 = sqlite3VdbeAddOp3(v, OP_Column, 0, 0, iRec); 297 j4 = sqlite3VdbeAddOp3(v, OP_Eq, memId-1, 0, iRec); 298 sqlite3VdbeAddOp2(v, OP_Next, 0, j3); 299 sqlite3VdbeJumpHere(v, j2); 300 sqlite3VdbeAddOp2(v, OP_NewRowid, 0, memId+1); 301 j5 = sqlite3VdbeAddOp0(v, OP_Goto); 302 sqlite3VdbeJumpHere(v, j4); 303 sqlite3VdbeAddOp2(v, OP_Rowid, 0, memId+1); 304 sqlite3VdbeJumpHere(v, j1); 305 sqlite3VdbeJumpHere(v, j5); 306 sqlite3VdbeAddOp3(v, OP_MakeRecord, memId-1, 2, iRec); 307 sqlite3VdbeAddOp3(v, OP_Insert, 0, iRec, memId+1); 308 sqlite3VdbeChangeP5(v, OPFLAG_APPEND); 309 sqlite3VdbeAddOp0(v, OP_Close); 310 sqlite3ReleaseTempReg(pParse, iRec); 311 } 312 } 313 #else 314 /* 315 ** If SQLITE_OMIT_AUTOINCREMENT is defined, then the three routines 316 ** above are all no-ops 317 */ 318 # define autoIncBegin(A,B,C) (0) 319 # define autoIncStep(A,B,C) 320 #endif /* SQLITE_OMIT_AUTOINCREMENT */ 321 322 323 /* Forward declaration */ 324 static int xferOptimization( 325 Parse *pParse, /* Parser context */ 326 Table *pDest, /* The table we are inserting into */ 327 Select *pSelect, /* A SELECT statement to use as the data source */ 328 int onError, /* How to handle constraint errors */ 329 int iDbDest /* The database of pDest */ 330 ); 331 332 /* 333 ** This routine is call to handle SQL of the following forms: 334 ** 335 ** insert into TABLE (IDLIST) values(EXPRLIST) 336 ** insert into TABLE (IDLIST) select 337 ** 338 ** The IDLIST following the table name is always optional. If omitted, 339 ** then a list of all columns for the table is substituted. The IDLIST 340 ** appears in the pColumn parameter. pColumn is NULL if IDLIST is omitted. 341 ** 342 ** The pList parameter holds EXPRLIST in the first form of the INSERT 343 ** statement above, and pSelect is NULL. For the second form, pList is 344 ** NULL and pSelect is a pointer to the select statement used to generate 345 ** data for the insert. 346 ** 347 ** The code generated follows one of four templates. For a simple 348 ** select with data coming from a VALUES clause, the code executes 349 ** once straight down through. Pseudo-code follows (we call this 350 ** the "1st template"): 351 ** 352 ** open write cursor to <table> and its indices 353 ** puts VALUES clause expressions onto the stack 354 ** write the resulting record into <table> 355 ** cleanup 356 ** 357 ** The three remaining templates assume the statement is of the form 358 ** 359 ** INSERT INTO <table> SELECT ... 360 ** 361 ** If the SELECT clause is of the restricted form "SELECT * FROM <table2>" - 362 ** in other words if the SELECT pulls all columns from a single table 363 ** and there is no WHERE or LIMIT or GROUP BY or ORDER BY clauses, and 364 ** if <table2> and <table1> are distinct tables but have identical 365 ** schemas, including all the same indices, then a special optimization 366 ** is invoked that copies raw records from <table2> over to <table1>. 367 ** See the xferOptimization() function for the implementation of this 368 ** template. This is the 2nd template. 369 ** 370 ** open a write cursor to <table> 371 ** open read cursor on <table2> 372 ** transfer all records in <table2> over to <table> 373 ** close cursors 374 ** foreach index on <table> 375 ** open a write cursor on the <table> index 376 ** open a read cursor on the corresponding <table2> index 377 ** transfer all records from the read to the write cursors 378 ** close cursors 379 ** end foreach 380 ** 381 ** The 3rd template is for when the second template does not apply 382 ** and the SELECT clause does not read from <table> at any time. 383 ** The generated code follows this template: 384 ** 385 ** EOF <- 0 386 ** X <- A 387 ** goto B 388 ** A: setup for the SELECT 389 ** loop over the rows in the SELECT 390 ** load values into registers R..R+n 391 ** yield X 392 ** end loop 393 ** cleanup after the SELECT 394 ** EOF <- 1 395 ** yield X 396 ** goto A 397 ** B: open write cursor to <table> and its indices 398 ** C: yield X 399 ** if EOF goto D 400 ** insert the select result into <table> from R..R+n 401 ** goto C 402 ** D: cleanup 403 ** 404 ** The 4th template is used if the insert statement takes its 405 ** values from a SELECT but the data is being inserted into a table 406 ** that is also read as part of the SELECT. In the third form, 407 ** we have to use a intermediate table to store the results of 408 ** the select. The template is like this: 409 ** 410 ** EOF <- 0 411 ** X <- A 412 ** goto B 413 ** A: setup for the SELECT 414 ** loop over the tables in the SELECT 415 ** load value into register R..R+n 416 ** yield X 417 ** end loop 418 ** cleanup after the SELECT 419 ** EOF <- 1 420 ** yield X 421 ** halt-error 422 ** B: open temp table 423 ** L: yield X 424 ** if EOF goto M 425 ** insert row from R..R+n into temp table 426 ** goto L 427 ** M: open write cursor to <table> and its indices 428 ** rewind temp table 429 ** C: loop over rows of intermediate table 430 ** transfer values form intermediate table into <table> 431 ** end loop 432 ** D: cleanup 433 */ 434 void sqlite3Insert( 435 Parse *pParse, /* Parser context */ 436 SrcList *pTabList, /* Name of table into which we are inserting */ 437 ExprList *pList, /* List of values to be inserted */ 438 Select *pSelect, /* A SELECT statement to use as the data source */ 439 IdList *pColumn, /* Column names corresponding to IDLIST. */ 440 int onError /* How to handle constraint errors */ 441 ){ 442 sqlite3 *db; /* The main database structure */ 443 Table *pTab; /* The table to insert into. aka TABLE */ 444 char *zTab; /* Name of the table into which we are inserting */ 445 const char *zDb; /* Name of the database holding this table */ 446 int i, j, idx; /* Loop counters */ 447 Vdbe *v; /* Generate code into this virtual machine */ 448 Index *pIdx; /* For looping over indices of the table */ 449 int nColumn; /* Number of columns in the data */ 450 int nHidden = 0; /* Number of hidden columns if TABLE is virtual */ 451 int baseCur = 0; /* VDBE Cursor number for pTab */ 452 int keyColumn = -1; /* Column that is the INTEGER PRIMARY KEY */ 453 int endOfLoop; /* Label for the end of the insertion loop */ 454 int useTempTable = 0; /* Store SELECT results in intermediate table */ 455 int srcTab = 0; /* Data comes from this temporary cursor if >=0 */ 456 int addrInsTop = 0; /* Jump to label "D" */ 457 int addrCont = 0; /* Top of insert loop. Label "C" in templates 3 and 4 */ 458 int addrSelect = 0; /* Address of coroutine that implements the SELECT */ 459 SelectDest dest; /* Destination for SELECT on rhs of INSERT */ 460 int iDb; /* Index of database holding TABLE */ 461 Db *pDb; /* The database containing table being inserted into */ 462 int appendFlag = 0; /* True if the insert is likely to be an append */ 463 464 /* Register allocations */ 465 int regFromSelect = 0;/* Base register for data coming from SELECT */ 466 int regAutoinc = 0; /* Register holding the AUTOINCREMENT counter */ 467 int regRowCount = 0; /* Memory cell used for the row counter */ 468 int regIns; /* Block of regs holding rowid+data being inserted */ 469 int regRowid; /* registers holding insert rowid */ 470 int regData; /* register holding first column to insert */ 471 int regEof = 0; /* Register recording end of SELECT data */ 472 int *aRegIdx = 0; /* One register allocated to each index */ 473 474 #ifndef SQLITE_OMIT_TRIGGER 475 int isView; /* True if attempting to insert into a view */ 476 Trigger *pTrigger; /* List of triggers on pTab, if required */ 477 int tmask; /* Mask of trigger times */ 478 #endif 479 480 db = pParse->db; 481 memset(&dest, 0, sizeof(dest)); 482 if( pParse->nErr || db->mallocFailed ){ 483 goto insert_cleanup; 484 } 485 486 /* Locate the table into which we will be inserting new information. 487 */ 488 assert( pTabList->nSrc==1 ); 489 zTab = pTabList->a[0].zName; 490 if( NEVER(zTab==0) ) goto insert_cleanup; 491 pTab = sqlite3SrcListLookup(pParse, pTabList); 492 if( pTab==0 ){ 493 goto insert_cleanup; 494 } 495 iDb = sqlite3SchemaToIndex(db, pTab->pSchema); 496 assert( iDb<db->nDb ); 497 pDb = &db->aDb[iDb]; 498 zDb = pDb->zName; 499 if( sqlite3AuthCheck(pParse, SQLITE_INSERT, pTab->zName, 0, zDb) ){ 500 goto insert_cleanup; 501 } 502 503 /* Figure out if we have any triggers and if the table being 504 ** inserted into is a view 505 */ 506 #ifndef SQLITE_OMIT_TRIGGER 507 pTrigger = sqlite3TriggersExist(pParse, pTab, TK_INSERT, 0, &tmask); 508 isView = pTab->pSelect!=0; 509 #else 510 # define pTrigger 0 511 # define tmask 0 512 # define isView 0 513 #endif 514 #ifdef SQLITE_OMIT_VIEW 515 # undef isView 516 # define isView 0 517 #endif 518 assert( (pTrigger && tmask) || (pTrigger==0 && tmask==0) ); 519 520 /* If pTab is really a view, make sure it has been initialized. 521 ** ViewGetColumnNames() is a no-op if pTab is not a view (or virtual 522 ** module table). 523 */ 524 if( sqlite3ViewGetColumnNames(pParse, pTab) ){ 525 goto insert_cleanup; 526 } 527 528 /* Ensure that: 529 * (a) the table is not read-only, 530 * (b) that if it is a view then ON INSERT triggers exist 531 */ 532 if( sqlite3IsReadOnly(pParse, pTab, tmask) ){ 533 goto insert_cleanup; 534 } 535 536 /* Allocate a VDBE 537 */ 538 v = sqlite3GetVdbe(pParse); 539 if( v==0 ) goto insert_cleanup; 540 if( pParse->nested==0 ) sqlite3VdbeCountChanges(v); 541 sqlite3BeginWriteOperation(pParse, pSelect || pTrigger, iDb); 542 543 #ifndef SQLITE_OMIT_XFER_OPT 544 /* If the statement is of the form 545 ** 546 ** INSERT INTO <table1> SELECT * FROM <table2>; 547 ** 548 ** Then special optimizations can be applied that make the transfer 549 ** very fast and which reduce fragmentation of indices. 550 ** 551 ** This is the 2nd template. 552 */ 553 if( pColumn==0 && xferOptimization(pParse, pTab, pSelect, onError, iDb) ){ 554 assert( !pTrigger ); 555 assert( pList==0 ); 556 goto insert_end; 557 } 558 #endif /* SQLITE_OMIT_XFER_OPT */ 559 560 /* If this is an AUTOINCREMENT table, look up the sequence number in the 561 ** sqlite_sequence table and store it in memory cell regAutoinc. 562 */ 563 regAutoinc = autoIncBegin(pParse, iDb, pTab); 564 565 /* Figure out how many columns of data are supplied. If the data 566 ** is coming from a SELECT statement, then generate a co-routine that 567 ** produces a single row of the SELECT on each invocation. The 568 ** co-routine is the common header to the 3rd and 4th templates. 569 */ 570 if( pSelect ){ 571 /* Data is coming from a SELECT. Generate code to implement that SELECT 572 ** as a co-routine. The code is common to both the 3rd and 4th 573 ** templates: 574 ** 575 ** EOF <- 0 576 ** X <- A 577 ** goto B 578 ** A: setup for the SELECT 579 ** loop over the tables in the SELECT 580 ** load value into register R..R+n 581 ** yield X 582 ** end loop 583 ** cleanup after the SELECT 584 ** EOF <- 1 585 ** yield X 586 ** halt-error 587 ** 588 ** On each invocation of the co-routine, it puts a single row of the 589 ** SELECT result into registers dest.iMem...dest.iMem+dest.nMem-1. 590 ** (These output registers are allocated by sqlite3Select().) When 591 ** the SELECT completes, it sets the EOF flag stored in regEof. 592 */ 593 int rc, j1; 594 595 regEof = ++pParse->nMem; 596 sqlite3VdbeAddOp2(v, OP_Integer, 0, regEof); /* EOF <- 0 */ 597 VdbeComment((v, "SELECT eof flag")); 598 sqlite3SelectDestInit(&dest, SRT_Coroutine, ++pParse->nMem); 599 addrSelect = sqlite3VdbeCurrentAddr(v)+2; 600 sqlite3VdbeAddOp2(v, OP_Integer, addrSelect-1, dest.iParm); 601 j1 = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0); 602 VdbeComment((v, "Jump over SELECT coroutine")); 603 604 /* Resolve the expressions in the SELECT statement and execute it. */ 605 rc = sqlite3Select(pParse, pSelect, &dest); 606 assert( pParse->nErr==0 || rc ); 607 if( rc || NEVER(pParse->nErr) || db->mallocFailed ){ 608 goto insert_cleanup; 609 } 610 sqlite3VdbeAddOp2(v, OP_Integer, 1, regEof); /* EOF <- 1 */ 611 sqlite3VdbeAddOp1(v, OP_Yield, dest.iParm); /* yield X */ 612 sqlite3VdbeAddOp2(v, OP_Halt, SQLITE_INTERNAL, OE_Abort); 613 VdbeComment((v, "End of SELECT coroutine")); 614 sqlite3VdbeJumpHere(v, j1); /* label B: */ 615 616 regFromSelect = dest.iMem; 617 assert( pSelect->pEList ); 618 nColumn = pSelect->pEList->nExpr; 619 assert( dest.nMem==nColumn ); 620 621 /* Set useTempTable to TRUE if the result of the SELECT statement 622 ** should be written into a temporary table (template 4). Set to 623 ** FALSE if each* row of the SELECT can be written directly into 624 ** the destination table (template 3). 625 ** 626 ** A temp table must be used if the table being updated is also one 627 ** of the tables being read by the SELECT statement. Also use a 628 ** temp table in the case of row triggers. 629 */ 630 if( pTrigger || readsTable(pParse, addrSelect, iDb, pTab) ){ 631 useTempTable = 1; 632 } 633 634 if( useTempTable ){ 635 /* Invoke the coroutine to extract information from the SELECT 636 ** and add it to a transient table srcTab. The code generated 637 ** here is from the 4th template: 638 ** 639 ** B: open temp table 640 ** L: yield X 641 ** if EOF goto M 642 ** insert row from R..R+n into temp table 643 ** goto L 644 ** M: ... 645 */ 646 int regRec; /* Register to hold packed record */ 647 int regTempRowid; /* Register to hold temp table ROWID */ 648 int addrTop; /* Label "L" */ 649 int addrIf; /* Address of jump to M */ 650 651 srcTab = pParse->nTab++; 652 regRec = sqlite3GetTempReg(pParse); 653 regTempRowid = sqlite3GetTempReg(pParse); 654 sqlite3VdbeAddOp2(v, OP_OpenEphemeral, srcTab, nColumn); 655 addrTop = sqlite3VdbeAddOp1(v, OP_Yield, dest.iParm); 656 addrIf = sqlite3VdbeAddOp1(v, OP_If, regEof); 657 sqlite3VdbeAddOp3(v, OP_MakeRecord, regFromSelect, nColumn, regRec); 658 sqlite3VdbeAddOp2(v, OP_NewRowid, srcTab, regTempRowid); 659 sqlite3VdbeAddOp3(v, OP_Insert, srcTab, regRec, regTempRowid); 660 sqlite3VdbeAddOp2(v, OP_Goto, 0, addrTop); 661 sqlite3VdbeJumpHere(v, addrIf); 662 sqlite3ReleaseTempReg(pParse, regRec); 663 sqlite3ReleaseTempReg(pParse, regTempRowid); 664 } 665 }else{ 666 /* This is the case if the data for the INSERT is coming from a VALUES 667 ** clause 668 */ 669 NameContext sNC; 670 memset(&sNC, 0, sizeof(sNC)); 671 sNC.pParse = pParse; 672 srcTab = -1; 673 assert( useTempTable==0 ); 674 nColumn = pList ? pList->nExpr : 0; 675 for(i=0; i<nColumn; i++){ 676 if( sqlite3ResolveExprNames(&sNC, pList->a[i].pExpr) ){ 677 goto insert_cleanup; 678 } 679 } 680 } 681 682 /* Make sure the number of columns in the source data matches the number 683 ** of columns to be inserted into the table. 684 */ 685 if( IsVirtual(pTab) ){ 686 for(i=0; i<pTab->nCol; i++){ 687 nHidden += (IsHiddenColumn(&pTab->aCol[i]) ? 1 : 0); 688 } 689 } 690 if( pColumn==0 && nColumn && nColumn!=(pTab->nCol-nHidden) ){ 691 sqlite3ErrorMsg(pParse, 692 "table %S has %d columns but %d values were supplied", 693 pTabList, 0, pTab->nCol-nHidden, nColumn); 694 goto insert_cleanup; 695 } 696 if( pColumn!=0 && nColumn!=pColumn->nId ){ 697 sqlite3ErrorMsg(pParse, "%d values for %d columns", nColumn, pColumn->nId); 698 goto insert_cleanup; 699 } 700 701 /* If the INSERT statement included an IDLIST term, then make sure 702 ** all elements of the IDLIST really are columns of the table and 703 ** remember the column indices. 704 ** 705 ** If the table has an INTEGER PRIMARY KEY column and that column 706 ** is named in the IDLIST, then record in the keyColumn variable 707 ** the index into IDLIST of the primary key column. keyColumn is 708 ** the index of the primary key as it appears in IDLIST, not as 709 ** is appears in the original table. (The index of the primary 710 ** key in the original table is pTab->iPKey.) 711 */ 712 if( pColumn ){ 713 for(i=0; i<pColumn->nId; i++){ 714 pColumn->a[i].idx = -1; 715 } 716 for(i=0; i<pColumn->nId; i++){ 717 for(j=0; j<pTab->nCol; j++){ 718 if( sqlite3StrICmp(pColumn->a[i].zName, pTab->aCol[j].zName)==0 ){ 719 pColumn->a[i].idx = j; 720 if( j==pTab->iPKey ){ 721 keyColumn = i; 722 } 723 break; 724 } 725 } 726 if( j>=pTab->nCol ){ 727 if( sqlite3IsRowid(pColumn->a[i].zName) ){ 728 keyColumn = i; 729 }else{ 730 sqlite3ErrorMsg(pParse, "table %S has no column named %s", 731 pTabList, 0, pColumn->a[i].zName); 732 pParse->checkSchema = 1; 733 goto insert_cleanup; 734 } 735 } 736 } 737 } 738 739 /* If there is no IDLIST term but the table has an integer primary 740 ** key, the set the keyColumn variable to the primary key column index 741 ** in the original table definition. 742 */ 743 if( pColumn==0 && nColumn>0 ){ 744 keyColumn = pTab->iPKey; 745 } 746 747 /* Initialize the count of rows to be inserted 748 */ 749 if( db->flags & SQLITE_CountRows ){ 750 regRowCount = ++pParse->nMem; 751 sqlite3VdbeAddOp2(v, OP_Integer, 0, regRowCount); 752 } 753 754 /* If this is not a view, open the table and and all indices */ 755 if( !isView ){ 756 int nIdx; 757 758 baseCur = pParse->nTab; 759 nIdx = sqlite3OpenTableAndIndices(pParse, pTab, baseCur, OP_OpenWrite); 760 aRegIdx = sqlite3DbMallocRaw(db, sizeof(int)*(nIdx+1)); 761 if( aRegIdx==0 ){ 762 goto insert_cleanup; 763 } 764 for(i=0; i<nIdx; i++){ 765 aRegIdx[i] = ++pParse->nMem; 766 } 767 } 768 769 /* This is the top of the main insertion loop */ 770 if( useTempTable ){ 771 /* This block codes the top of loop only. The complete loop is the 772 ** following pseudocode (template 4): 773 ** 774 ** rewind temp table 775 ** C: loop over rows of intermediate table 776 ** transfer values form intermediate table into <table> 777 ** end loop 778 ** D: ... 779 */ 780 addrInsTop = sqlite3VdbeAddOp1(v, OP_Rewind, srcTab); 781 addrCont = sqlite3VdbeCurrentAddr(v); 782 }else if( pSelect ){ 783 /* This block codes the top of loop only. The complete loop is the 784 ** following pseudocode (template 3): 785 ** 786 ** C: yield X 787 ** if EOF goto D 788 ** insert the select result into <table> from R..R+n 789 ** goto C 790 ** D: ... 791 */ 792 addrCont = sqlite3VdbeAddOp1(v, OP_Yield, dest.iParm); 793 addrInsTop = sqlite3VdbeAddOp1(v, OP_If, regEof); 794 } 795 796 /* Allocate registers for holding the rowid of the new row, 797 ** the content of the new row, and the assemblied row record. 798 */ 799 regRowid = regIns = pParse->nMem+1; 800 pParse->nMem += pTab->nCol + 1; 801 if( IsVirtual(pTab) ){ 802 regRowid++; 803 pParse->nMem++; 804 } 805 regData = regRowid+1; 806 807 /* Run the BEFORE and INSTEAD OF triggers, if there are any 808 */ 809 endOfLoop = sqlite3VdbeMakeLabel(v); 810 if( tmask & TRIGGER_BEFORE ){ 811 int regCols = sqlite3GetTempRange(pParse, pTab->nCol+1); 812 813 /* build the NEW.* reference row. Note that if there is an INTEGER 814 ** PRIMARY KEY into which a NULL is being inserted, that NULL will be 815 ** translated into a unique ID for the row. But on a BEFORE trigger, 816 ** we do not know what the unique ID will be (because the insert has 817 ** not happened yet) so we substitute a rowid of -1 818 */ 819 if( keyColumn<0 ){ 820 sqlite3VdbeAddOp2(v, OP_Integer, -1, regCols); 821 }else{ 822 int j1; 823 if( useTempTable ){ 824 sqlite3VdbeAddOp3(v, OP_Column, srcTab, keyColumn, regCols); 825 }else{ 826 assert( pSelect==0 ); /* Otherwise useTempTable is true */ 827 sqlite3ExprCode(pParse, pList->a[keyColumn].pExpr, regCols); 828 } 829 j1 = sqlite3VdbeAddOp1(v, OP_NotNull, regCols); 830 sqlite3VdbeAddOp2(v, OP_Integer, -1, regCols); 831 sqlite3VdbeJumpHere(v, j1); 832 sqlite3VdbeAddOp1(v, OP_MustBeInt, regCols); 833 } 834 835 /* Cannot have triggers on a virtual table. If it were possible, 836 ** this block would have to account for hidden column. 837 */ 838 assert( !IsVirtual(pTab) ); 839 840 /* Create the new column data 841 */ 842 for(i=0; i<pTab->nCol; i++){ 843 if( pColumn==0 ){ 844 j = i; 845 }else{ 846 for(j=0; j<pColumn->nId; j++){ 847 if( pColumn->a[j].idx==i ) break; 848 } 849 } 850 if( (!useTempTable && !pList) || (pColumn && j>=pColumn->nId) ){ 851 sqlite3ExprCode(pParse, pTab->aCol[i].pDflt, regCols+i+1); 852 }else if( useTempTable ){ 853 sqlite3VdbeAddOp3(v, OP_Column, srcTab, j, regCols+i+1); 854 }else{ 855 assert( pSelect==0 ); /* Otherwise useTempTable is true */ 856 sqlite3ExprCodeAndCache(pParse, pList->a[j].pExpr, regCols+i+1); 857 } 858 } 859 860 /* If this is an INSERT on a view with an INSTEAD OF INSERT trigger, 861 ** do not attempt any conversions before assembling the record. 862 ** If this is a real table, attempt conversions as required by the 863 ** table column affinities. 864 */ 865 if( !isView ){ 866 sqlite3VdbeAddOp2(v, OP_Affinity, regCols+1, pTab->nCol); 867 sqlite3TableAffinityStr(v, pTab); 868 } 869 870 /* Fire BEFORE or INSTEAD OF triggers */ 871 sqlite3CodeRowTrigger(pParse, pTrigger, TK_INSERT, 0, TRIGGER_BEFORE, 872 pTab, regCols-pTab->nCol-1, onError, endOfLoop); 873 874 sqlite3ReleaseTempRange(pParse, regCols, pTab->nCol+1); 875 } 876 877 /* Push the record number for the new entry onto the stack. The 878 ** record number is a randomly generate integer created by NewRowid 879 ** except when the table has an INTEGER PRIMARY KEY column, in which 880 ** case the record number is the same as that column. 881 */ 882 if( !isView ){ 883 if( IsVirtual(pTab) ){ 884 /* The row that the VUpdate opcode will delete: none */ 885 sqlite3VdbeAddOp2(v, OP_Null, 0, regIns); 886 } 887 if( keyColumn>=0 ){ 888 if( useTempTable ){ 889 sqlite3VdbeAddOp3(v, OP_Column, srcTab, keyColumn, regRowid); 890 }else if( pSelect ){ 891 sqlite3VdbeAddOp2(v, OP_SCopy, regFromSelect+keyColumn, regRowid); 892 }else{ 893 VdbeOp *pOp; 894 sqlite3ExprCode(pParse, pList->a[keyColumn].pExpr, regRowid); 895 pOp = sqlite3VdbeGetOp(v, -1); 896 if( ALWAYS(pOp) && pOp->opcode==OP_Null && !IsVirtual(pTab) ){ 897 appendFlag = 1; 898 pOp->opcode = OP_NewRowid; 899 pOp->p1 = baseCur; 900 pOp->p2 = regRowid; 901 pOp->p3 = regAutoinc; 902 } 903 } 904 /* If the PRIMARY KEY expression is NULL, then use OP_NewRowid 905 ** to generate a unique primary key value. 906 */ 907 if( !appendFlag ){ 908 int j1; 909 if( !IsVirtual(pTab) ){ 910 j1 = sqlite3VdbeAddOp1(v, OP_NotNull, regRowid); 911 sqlite3VdbeAddOp3(v, OP_NewRowid, baseCur, regRowid, regAutoinc); 912 sqlite3VdbeJumpHere(v, j1); 913 }else{ 914 j1 = sqlite3VdbeCurrentAddr(v); 915 sqlite3VdbeAddOp2(v, OP_IsNull, regRowid, j1+2); 916 } 917 sqlite3VdbeAddOp1(v, OP_MustBeInt, regRowid); 918 } 919 }else if( IsVirtual(pTab) ){ 920 sqlite3VdbeAddOp2(v, OP_Null, 0, regRowid); 921 }else{ 922 sqlite3VdbeAddOp3(v, OP_NewRowid, baseCur, regRowid, regAutoinc); 923 appendFlag = 1; 924 } 925 autoIncStep(pParse, regAutoinc, regRowid); 926 927 /* Push onto the stack, data for all columns of the new entry, beginning 928 ** with the first column. 929 */ 930 nHidden = 0; 931 for(i=0; i<pTab->nCol; i++){ 932 int iRegStore = regRowid+1+i; 933 if( i==pTab->iPKey ){ 934 /* The value of the INTEGER PRIMARY KEY column is always a NULL. 935 ** Whenever this column is read, the record number will be substituted 936 ** in its place. So will fill this column with a NULL to avoid 937 ** taking up data space with information that will never be used. */ 938 sqlite3VdbeAddOp2(v, OP_Null, 0, iRegStore); 939 continue; 940 } 941 if( pColumn==0 ){ 942 if( IsHiddenColumn(&pTab->aCol[i]) ){ 943 assert( IsVirtual(pTab) ); 944 j = -1; 945 nHidden++; 946 }else{ 947 j = i - nHidden; 948 } 949 }else{ 950 for(j=0; j<pColumn->nId; j++){ 951 if( pColumn->a[j].idx==i ) break; 952 } 953 } 954 if( j<0 || nColumn==0 || (pColumn && j>=pColumn->nId) ){ 955 sqlite3ExprCode(pParse, pTab->aCol[i].pDflt, iRegStore); 956 }else if( useTempTable ){ 957 sqlite3VdbeAddOp3(v, OP_Column, srcTab, j, iRegStore); 958 }else if( pSelect ){ 959 sqlite3VdbeAddOp2(v, OP_SCopy, regFromSelect+j, iRegStore); 960 }else{ 961 sqlite3ExprCode(pParse, pList->a[j].pExpr, iRegStore); 962 } 963 } 964 965 /* Generate code to check constraints and generate index keys and 966 ** do the insertion. 967 */ 968 #ifndef SQLITE_OMIT_VIRTUALTABLE 969 if( IsVirtual(pTab) ){ 970 const char *pVTab = (const char *)sqlite3GetVTable(db, pTab); 971 sqlite3VtabMakeWritable(pParse, pTab); 972 sqlite3VdbeAddOp4(v, OP_VUpdate, 1, pTab->nCol+2, regIns, pVTab, P4_VTAB); 973 sqlite3VdbeChangeP5(v, onError==OE_Default ? OE_Abort : onError); 974 sqlite3MayAbort(pParse); 975 }else 976 #endif 977 { 978 int isReplace; /* Set to true if constraints may cause a replace */ 979 sqlite3GenerateConstraintChecks(pParse, pTab, baseCur, regIns, aRegIdx, 980 keyColumn>=0, 0, onError, endOfLoop, &isReplace 981 ); 982 sqlite3FkCheck(pParse, pTab, 0, regIns); 983 sqlite3CompleteInsertion( 984 pParse, pTab, baseCur, regIns, aRegIdx, 0, appendFlag, isReplace==0 985 ); 986 } 987 } 988 989 /* Update the count of rows that are inserted 990 */ 991 if( (db->flags & SQLITE_CountRows)!=0 ){ 992 sqlite3VdbeAddOp2(v, OP_AddImm, regRowCount, 1); 993 } 994 995 if( pTrigger ){ 996 /* Code AFTER triggers */ 997 sqlite3CodeRowTrigger(pParse, pTrigger, TK_INSERT, 0, TRIGGER_AFTER, 998 pTab, regData-2-pTab->nCol, onError, endOfLoop); 999 } 1000 1001 /* The bottom of the main insertion loop, if the data source 1002 ** is a SELECT statement. 1003 */ 1004 sqlite3VdbeResolveLabel(v, endOfLoop); 1005 if( useTempTable ){ 1006 sqlite3VdbeAddOp2(v, OP_Next, srcTab, addrCont); 1007 sqlite3VdbeJumpHere(v, addrInsTop); 1008 sqlite3VdbeAddOp1(v, OP_Close, srcTab); 1009 }else if( pSelect ){ 1010 sqlite3VdbeAddOp2(v, OP_Goto, 0, addrCont); 1011 sqlite3VdbeJumpHere(v, addrInsTop); 1012 } 1013 1014 if( !IsVirtual(pTab) && !isView ){ 1015 /* Close all tables opened */ 1016 sqlite3VdbeAddOp1(v, OP_Close, baseCur); 1017 for(idx=1, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, idx++){ 1018 sqlite3VdbeAddOp1(v, OP_Close, idx+baseCur); 1019 } 1020 } 1021 1022 insert_end: 1023 /* Update the sqlite_sequence table by storing the content of the 1024 ** maximum rowid counter values recorded while inserting into 1025 ** autoincrement tables. 1026 */ 1027 if( pParse->nested==0 && pParse->pTriggerTab==0 ){ 1028 sqlite3AutoincrementEnd(pParse); 1029 } 1030 1031 /* 1032 ** Return the number of rows inserted. If this routine is 1033 ** generating code because of a call to sqlite3NestedParse(), do not 1034 ** invoke the callback function. 1035 */ 1036 if( (db->flags&SQLITE_CountRows) && !pParse->nested && !pParse->pTriggerTab ){ 1037 sqlite3VdbeAddOp2(v, OP_ResultRow, regRowCount, 1); 1038 sqlite3VdbeSetNumCols(v, 1); 1039 sqlite3VdbeSetColName(v, 0, COLNAME_NAME, "rows inserted", SQLITE_STATIC); 1040 } 1041 1042 insert_cleanup: 1043 sqlite3SrcListDelete(db, pTabList); 1044 sqlite3ExprListDelete(db, pList); 1045 sqlite3SelectDelete(db, pSelect); 1046 sqlite3IdListDelete(db, pColumn); 1047 sqlite3DbFree(db, aRegIdx); 1048 } 1049 1050 /* Make sure "isView" and other macros defined above are undefined. Otherwise 1051 ** thely may interfere with compilation of other functions in this file 1052 ** (or in another file, if this file becomes part of the amalgamation). */ 1053 #ifdef isView 1054 #undef isView 1055 #endif 1056 #ifdef pTrigger 1057 #undef pTrigger 1058 #endif 1059 #ifdef tmask 1060 #undef tmask 1061 #endif 1062 1063 1064 /* 1065 ** Generate code to do constraint checks prior to an INSERT or an UPDATE. 1066 ** 1067 ** The input is a range of consecutive registers as follows: 1068 ** 1069 ** 1. The rowid of the row after the update. 1070 ** 1071 ** 2. The data in the first column of the entry after the update. 1072 ** 1073 ** i. Data from middle columns... 1074 ** 1075 ** N. The data in the last column of the entry after the update. 1076 ** 1077 ** The regRowid parameter is the index of the register containing (1). 1078 ** 1079 ** If isUpdate is true and rowidChng is non-zero, then rowidChng contains 1080 ** the address of a register containing the rowid before the update takes 1081 ** place. isUpdate is true for UPDATEs and false for INSERTs. If isUpdate 1082 ** is false, indicating an INSERT statement, then a non-zero rowidChng 1083 ** indicates that the rowid was explicitly specified as part of the 1084 ** INSERT statement. If rowidChng is false, it means that the rowid is 1085 ** computed automatically in an insert or that the rowid value is not 1086 ** modified by an update. 1087 ** 1088 ** The code generated by this routine store new index entries into 1089 ** registers identified by aRegIdx[]. No index entry is created for 1090 ** indices where aRegIdx[i]==0. The order of indices in aRegIdx[] is 1091 ** the same as the order of indices on the linked list of indices 1092 ** attached to the table. 1093 ** 1094 ** This routine also generates code to check constraints. NOT NULL, 1095 ** CHECK, and UNIQUE constraints are all checked. If a constraint fails, 1096 ** then the appropriate action is performed. There are five possible 1097 ** actions: ROLLBACK, ABORT, FAIL, REPLACE, and IGNORE. 1098 ** 1099 ** Constraint type Action What Happens 1100 ** --------------- ---------- ---------------------------------------- 1101 ** any ROLLBACK The current transaction is rolled back and 1102 ** sqlite3_exec() returns immediately with a 1103 ** return code of SQLITE_CONSTRAINT. 1104 ** 1105 ** any ABORT Back out changes from the current command 1106 ** only (do not do a complete rollback) then 1107 ** cause sqlite3_exec() to return immediately 1108 ** with SQLITE_CONSTRAINT. 1109 ** 1110 ** any FAIL Sqlite3_exec() returns immediately with a 1111 ** return code of SQLITE_CONSTRAINT. The 1112 ** transaction is not rolled back and any 1113 ** prior changes are retained. 1114 ** 1115 ** any IGNORE The record number and data is popped from 1116 ** the stack and there is an immediate jump 1117 ** to label ignoreDest. 1118 ** 1119 ** NOT NULL REPLACE The NULL value is replace by the default 1120 ** value for that column. If the default value 1121 ** is NULL, the action is the same as ABORT. 1122 ** 1123 ** UNIQUE REPLACE The other row that conflicts with the row 1124 ** being inserted is removed. 1125 ** 1126 ** CHECK REPLACE Illegal. The results in an exception. 1127 ** 1128 ** Which action to take is determined by the overrideError parameter. 1129 ** Or if overrideError==OE_Default, then the pParse->onError parameter 1130 ** is used. Or if pParse->onError==OE_Default then the onError value 1131 ** for the constraint is used. 1132 ** 1133 ** The calling routine must open a read/write cursor for pTab with 1134 ** cursor number "baseCur". All indices of pTab must also have open 1135 ** read/write cursors with cursor number baseCur+i for the i-th cursor. 1136 ** Except, if there is no possibility of a REPLACE action then 1137 ** cursors do not need to be open for indices where aRegIdx[i]==0. 1138 */ 1139 void sqlite3GenerateConstraintChecks( 1140 Parse *pParse, /* The parser context */ 1141 Table *pTab, /* the table into which we are inserting */ 1142 int baseCur, /* Index of a read/write cursor pointing at pTab */ 1143 int regRowid, /* Index of the range of input registers */ 1144 int *aRegIdx, /* Register used by each index. 0 for unused indices */ 1145 int rowidChng, /* True if the rowid might collide with existing entry */ 1146 int isUpdate, /* True for UPDATE, False for INSERT */ 1147 int overrideError, /* Override onError to this if not OE_Default */ 1148 int ignoreDest, /* Jump to this label on an OE_Ignore resolution */ 1149 int *pbMayReplace /* OUT: Set to true if constraint may cause a replace */ 1150 ){ 1151 int i; /* loop counter */ 1152 Vdbe *v; /* VDBE under constrution */ 1153 int nCol; /* Number of columns */ 1154 int onError; /* Conflict resolution strategy */ 1155 int j1; /* Addresss of jump instruction */ 1156 int j2 = 0, j3; /* Addresses of jump instructions */ 1157 int regData; /* Register containing first data column */ 1158 int iCur; /* Table cursor number */ 1159 Index *pIdx; /* Pointer to one of the indices */ 1160 sqlite3 *db; /* Database connection */ 1161 int seenReplace = 0; /* True if REPLACE is used to resolve INT PK conflict */ 1162 int regOldRowid = (rowidChng && isUpdate) ? rowidChng : regRowid; 1163 1164 db = pParse->db; 1165 v = sqlite3GetVdbe(pParse); 1166 assert( v!=0 ); 1167 assert( pTab->pSelect==0 ); /* This table is not a VIEW */ 1168 nCol = pTab->nCol; 1169 regData = regRowid + 1; 1170 1171 /* Test all NOT NULL constraints. 1172 */ 1173 for(i=0; i<nCol; i++){ 1174 if( i==pTab->iPKey ){ 1175 continue; 1176 } 1177 onError = pTab->aCol[i].notNull; 1178 if( onError==OE_None ) continue; 1179 if( overrideError!=OE_Default ){ 1180 onError = overrideError; 1181 }else if( onError==OE_Default ){ 1182 onError = OE_Abort; 1183 } 1184 if( onError==OE_Replace && pTab->aCol[i].pDflt==0 ){ 1185 onError = OE_Abort; 1186 } 1187 assert( onError==OE_Rollback || onError==OE_Abort || onError==OE_Fail 1188 || onError==OE_Ignore || onError==OE_Replace ); 1189 switch( onError ){ 1190 case OE_Abort: 1191 sqlite3MayAbort(pParse); 1192 case OE_Rollback: 1193 case OE_Fail: { 1194 char *zMsg; 1195 sqlite3VdbeAddOp3(v, OP_HaltIfNull, 1196 SQLITE_CONSTRAINT, onError, regData+i); 1197 zMsg = sqlite3MPrintf(db, "%s.%s may not be NULL", 1198 pTab->zName, pTab->aCol[i].zName); 1199 sqlite3VdbeChangeP4(v, -1, zMsg, P4_DYNAMIC); 1200 break; 1201 } 1202 case OE_Ignore: { 1203 sqlite3VdbeAddOp2(v, OP_IsNull, regData+i, ignoreDest); 1204 break; 1205 } 1206 default: { 1207 assert( onError==OE_Replace ); 1208 j1 = sqlite3VdbeAddOp1(v, OP_NotNull, regData+i); 1209 sqlite3ExprCode(pParse, pTab->aCol[i].pDflt, regData+i); 1210 sqlite3VdbeJumpHere(v, j1); 1211 break; 1212 } 1213 } 1214 } 1215 1216 /* Test all CHECK constraints 1217 */ 1218 #ifndef SQLITE_OMIT_CHECK 1219 if( pTab->pCheck && (db->flags & SQLITE_IgnoreChecks)==0 ){ 1220 ExprList *pCheck = pTab->pCheck; 1221 pParse->ckBase = regData; 1222 onError = overrideError!=OE_Default ? overrideError : OE_Abort; 1223 for(i=0; i<pCheck->nExpr; i++){ 1224 int allOk = sqlite3VdbeMakeLabel(v); 1225 sqlite3ExprIfTrue(pParse, pCheck->a[i].pExpr, allOk, SQLITE_JUMPIFNULL); 1226 if( onError==OE_Ignore ){ 1227 sqlite3VdbeAddOp2(v, OP_Goto, 0, ignoreDest); 1228 }else{ 1229 char *zConsName = pCheck->a[i].zName; 1230 if( onError==OE_Replace ) onError = OE_Abort; /* IMP: R-15569-63625 */ 1231 if( zConsName ){ 1232 zConsName = sqlite3MPrintf(db, "constraint %s failed", zConsName); 1233 }else{ 1234 zConsName = 0; 1235 } 1236 sqlite3HaltConstraint(pParse, onError, zConsName, P4_DYNAMIC); 1237 } 1238 sqlite3VdbeResolveLabel(v, allOk); 1239 } 1240 } 1241 #endif /* !defined(SQLITE_OMIT_CHECK) */ 1242 1243 /* If we have an INTEGER PRIMARY KEY, make sure the primary key 1244 ** of the new record does not previously exist. Except, if this 1245 ** is an UPDATE and the primary key is not changing, that is OK. 1246 */ 1247 if( rowidChng ){ 1248 onError = pTab->keyConf; 1249 if( overrideError!=OE_Default ){ 1250 onError = overrideError; 1251 }else if( onError==OE_Default ){ 1252 onError = OE_Abort; 1253 } 1254 1255 if( isUpdate ){ 1256 j2 = sqlite3VdbeAddOp3(v, OP_Eq, regRowid, 0, rowidChng); 1257 } 1258 j3 = sqlite3VdbeAddOp3(v, OP_NotExists, baseCur, 0, regRowid); 1259 switch( onError ){ 1260 default: { 1261 onError = OE_Abort; 1262 /* Fall thru into the next case */ 1263 } 1264 case OE_Rollback: 1265 case OE_Abort: 1266 case OE_Fail: { 1267 sqlite3HaltConstraint( 1268 pParse, onError, "PRIMARY KEY must be unique", P4_STATIC); 1269 break; 1270 } 1271 case OE_Replace: { 1272 /* If there are DELETE triggers on this table and the 1273 ** recursive-triggers flag is set, call GenerateRowDelete() to 1274 ** remove the conflicting row from the the table. This will fire 1275 ** the triggers and remove both the table and index b-tree entries. 1276 ** 1277 ** Otherwise, if there are no triggers or the recursive-triggers 1278 ** flag is not set, but the table has one or more indexes, call 1279 ** GenerateRowIndexDelete(). This removes the index b-tree entries 1280 ** only. The table b-tree entry will be replaced by the new entry 1281 ** when it is inserted. 1282 ** 1283 ** If either GenerateRowDelete() or GenerateRowIndexDelete() is called, 1284 ** also invoke MultiWrite() to indicate that this VDBE may require 1285 ** statement rollback (if the statement is aborted after the delete 1286 ** takes place). Earlier versions called sqlite3MultiWrite() regardless, 1287 ** but being more selective here allows statements like: 1288 ** 1289 ** REPLACE INTO t(rowid) VALUES($newrowid) 1290 ** 1291 ** to run without a statement journal if there are no indexes on the 1292 ** table. 1293 */ 1294 Trigger *pTrigger = 0; 1295 if( db->flags&SQLITE_RecTriggers ){ 1296 pTrigger = sqlite3TriggersExist(pParse, pTab, TK_DELETE, 0, 0); 1297 } 1298 if( pTrigger || sqlite3FkRequired(pParse, pTab, 0, 0) ){ 1299 sqlite3MultiWrite(pParse); 1300 sqlite3GenerateRowDelete( 1301 pParse, pTab, baseCur, regRowid, 0, pTrigger, OE_Replace 1302 ); 1303 }else if( pTab->pIndex ){ 1304 sqlite3MultiWrite(pParse); 1305 sqlite3GenerateRowIndexDelete(pParse, pTab, baseCur, 0); 1306 } 1307 seenReplace = 1; 1308 break; 1309 } 1310 case OE_Ignore: { 1311 assert( seenReplace==0 ); 1312 sqlite3VdbeAddOp2(v, OP_Goto, 0, ignoreDest); 1313 break; 1314 } 1315 } 1316 sqlite3VdbeJumpHere(v, j3); 1317 if( isUpdate ){ 1318 sqlite3VdbeJumpHere(v, j2); 1319 } 1320 } 1321 1322 /* Test all UNIQUE constraints by creating entries for each UNIQUE 1323 ** index and making sure that duplicate entries do not already exist. 1324 ** Add the new records to the indices as we go. 1325 */ 1326 for(iCur=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, iCur++){ 1327 int regIdx; 1328 int regR; 1329 1330 if( aRegIdx[iCur]==0 ) continue; /* Skip unused indices */ 1331 1332 /* Create a key for accessing the index entry */ 1333 regIdx = sqlite3GetTempRange(pParse, pIdx->nColumn+1); 1334 for(i=0; i<pIdx->nColumn; i++){ 1335 int idx = pIdx->aiColumn[i]; 1336 if( idx==pTab->iPKey ){ 1337 sqlite3VdbeAddOp2(v, OP_SCopy, regRowid, regIdx+i); 1338 }else{ 1339 sqlite3VdbeAddOp2(v, OP_SCopy, regData+idx, regIdx+i); 1340 } 1341 } 1342 sqlite3VdbeAddOp2(v, OP_SCopy, regRowid, regIdx+i); 1343 sqlite3VdbeAddOp3(v, OP_MakeRecord, regIdx, pIdx->nColumn+1, aRegIdx[iCur]); 1344 sqlite3VdbeChangeP4(v, -1, sqlite3IndexAffinityStr(v, pIdx), P4_TRANSIENT); 1345 sqlite3ExprCacheAffinityChange(pParse, regIdx, pIdx->nColumn+1); 1346 1347 /* Find out what action to take in case there is an indexing conflict */ 1348 onError = pIdx->onError; 1349 if( onError==OE_None ){ 1350 sqlite3ReleaseTempRange(pParse, regIdx, pIdx->nColumn+1); 1351 continue; /* pIdx is not a UNIQUE index */ 1352 } 1353 if( overrideError!=OE_Default ){ 1354 onError = overrideError; 1355 }else if( onError==OE_Default ){ 1356 onError = OE_Abort; 1357 } 1358 if( seenReplace ){ 1359 if( onError==OE_Ignore ) onError = OE_Replace; 1360 else if( onError==OE_Fail ) onError = OE_Abort; 1361 } 1362 1363 /* Check to see if the new index entry will be unique */ 1364 regR = sqlite3GetTempReg(pParse); 1365 sqlite3VdbeAddOp2(v, OP_SCopy, regOldRowid, regR); 1366 j3 = sqlite3VdbeAddOp4(v, OP_IsUnique, baseCur+iCur+1, 0, 1367 regR, SQLITE_INT_TO_PTR(regIdx), 1368 P4_INT32); 1369 sqlite3ReleaseTempRange(pParse, regIdx, pIdx->nColumn+1); 1370 1371 /* Generate code that executes if the new index entry is not unique */ 1372 assert( onError==OE_Rollback || onError==OE_Abort || onError==OE_Fail 1373 || onError==OE_Ignore || onError==OE_Replace ); 1374 switch( onError ){ 1375 case OE_Rollback: 1376 case OE_Abort: 1377 case OE_Fail: { 1378 int j; 1379 StrAccum errMsg; 1380 const char *zSep; 1381 char *zErr; 1382 1383 sqlite3StrAccumInit(&errMsg, 0, 0, 200); 1384 errMsg.db = db; 1385 zSep = pIdx->nColumn>1 ? "columns " : "column "; 1386 for(j=0; j<pIdx->nColumn; j++){ 1387 char *zCol = pTab->aCol[pIdx->aiColumn[j]].zName; 1388 sqlite3StrAccumAppend(&errMsg, zSep, -1); 1389 zSep = ", "; 1390 sqlite3StrAccumAppend(&errMsg, zCol, -1); 1391 } 1392 sqlite3StrAccumAppend(&errMsg, 1393 pIdx->nColumn>1 ? " are not unique" : " is not unique", -1); 1394 zErr = sqlite3StrAccumFinish(&errMsg); 1395 sqlite3HaltConstraint(pParse, onError, zErr, 0); 1396 sqlite3DbFree(errMsg.db, zErr); 1397 break; 1398 } 1399 case OE_Ignore: { 1400 assert( seenReplace==0 ); 1401 sqlite3VdbeAddOp2(v, OP_Goto, 0, ignoreDest); 1402 break; 1403 } 1404 default: { 1405 Trigger *pTrigger = 0; 1406 assert( onError==OE_Replace ); 1407 sqlite3MultiWrite(pParse); 1408 if( db->flags&SQLITE_RecTriggers ){ 1409 pTrigger = sqlite3TriggersExist(pParse, pTab, TK_DELETE, 0, 0); 1410 } 1411 sqlite3GenerateRowDelete( 1412 pParse, pTab, baseCur, regR, 0, pTrigger, OE_Replace 1413 ); 1414 seenReplace = 1; 1415 break; 1416 } 1417 } 1418 sqlite3VdbeJumpHere(v, j3); 1419 sqlite3ReleaseTempReg(pParse, regR); 1420 } 1421 1422 if( pbMayReplace ){ 1423 *pbMayReplace = seenReplace; 1424 } 1425 } 1426 1427 /* 1428 ** This routine generates code to finish the INSERT or UPDATE operation 1429 ** that was started by a prior call to sqlite3GenerateConstraintChecks. 1430 ** A consecutive range of registers starting at regRowid contains the 1431 ** rowid and the content to be inserted. 1432 ** 1433 ** The arguments to this routine should be the same as the first six 1434 ** arguments to sqlite3GenerateConstraintChecks. 1435 */ 1436 void sqlite3CompleteInsertion( 1437 Parse *pParse, /* The parser context */ 1438 Table *pTab, /* the table into which we are inserting */ 1439 int baseCur, /* Index of a read/write cursor pointing at pTab */ 1440 int regRowid, /* Range of content */ 1441 int *aRegIdx, /* Register used by each index. 0 for unused indices */ 1442 int isUpdate, /* True for UPDATE, False for INSERT */ 1443 int appendBias, /* True if this is likely to be an append */ 1444 int useSeekResult /* True to set the USESEEKRESULT flag on OP_[Idx]Insert */ 1445 ){ 1446 int i; 1447 Vdbe *v; 1448 int nIdx; 1449 Index *pIdx; 1450 u8 pik_flags; 1451 int regData; 1452 int regRec; 1453 1454 v = sqlite3GetVdbe(pParse); 1455 assert( v!=0 ); 1456 assert( pTab->pSelect==0 ); /* This table is not a VIEW */ 1457 for(nIdx=0, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, nIdx++){} 1458 for(i=nIdx-1; i>=0; i--){ 1459 if( aRegIdx[i]==0 ) continue; 1460 sqlite3VdbeAddOp2(v, OP_IdxInsert, baseCur+i+1, aRegIdx[i]); 1461 if( useSeekResult ){ 1462 sqlite3VdbeChangeP5(v, OPFLAG_USESEEKRESULT); 1463 } 1464 } 1465 regData = regRowid + 1; 1466 regRec = sqlite3GetTempReg(pParse); 1467 sqlite3VdbeAddOp3(v, OP_MakeRecord, regData, pTab->nCol, regRec); 1468 sqlite3TableAffinityStr(v, pTab); 1469 sqlite3ExprCacheAffinityChange(pParse, regData, pTab->nCol); 1470 if( pParse->nested ){ 1471 pik_flags = 0; 1472 }else{ 1473 pik_flags = OPFLAG_NCHANGE; 1474 pik_flags |= (isUpdate?OPFLAG_ISUPDATE:OPFLAG_LASTROWID); 1475 } 1476 if( appendBias ){ 1477 pik_flags |= OPFLAG_APPEND; 1478 } 1479 if( useSeekResult ){ 1480 pik_flags |= OPFLAG_USESEEKRESULT; 1481 } 1482 sqlite3VdbeAddOp3(v, OP_Insert, baseCur, regRec, regRowid); 1483 if( !pParse->nested ){ 1484 sqlite3VdbeChangeP4(v, -1, pTab->zName, P4_TRANSIENT); 1485 } 1486 sqlite3VdbeChangeP5(v, pik_flags); 1487 } 1488 1489 /* 1490 ** Generate code that will open cursors for a table and for all 1491 ** indices of that table. The "baseCur" parameter is the cursor number used 1492 ** for the table. Indices are opened on subsequent cursors. 1493 ** 1494 ** Return the number of indices on the table. 1495 */ 1496 int sqlite3OpenTableAndIndices( 1497 Parse *pParse, /* Parsing context */ 1498 Table *pTab, /* Table to be opened */ 1499 int baseCur, /* Cursor number assigned to the table */ 1500 int op /* OP_OpenRead or OP_OpenWrite */ 1501 ){ 1502 int i; 1503 int iDb; 1504 Index *pIdx; 1505 Vdbe *v; 1506 1507 if( IsVirtual(pTab) ) return 0; 1508 iDb = sqlite3SchemaToIndex(pParse->db, pTab->pSchema); 1509 v = sqlite3GetVdbe(pParse); 1510 assert( v!=0 ); 1511 sqlite3OpenTable(pParse, baseCur, iDb, pTab, op); 1512 for(i=1, pIdx=pTab->pIndex; pIdx; pIdx=pIdx->pNext, i++){ 1513 KeyInfo *pKey = sqlite3IndexKeyinfo(pParse, pIdx); 1514 assert( pIdx->pSchema==pTab->pSchema ); 1515 sqlite3VdbeAddOp4(v, op, i+baseCur, pIdx->tnum, iDb, 1516 (char*)pKey, P4_KEYINFO_HANDOFF); 1517 VdbeComment((v, "%s", pIdx->zName)); 1518 } 1519 if( pParse->nTab<baseCur+i ){ 1520 pParse->nTab = baseCur+i; 1521 } 1522 return i-1; 1523 } 1524 1525 1526 #ifdef SQLITE_TEST 1527 /* 1528 ** The following global variable is incremented whenever the 1529 ** transfer optimization is used. This is used for testing 1530 ** purposes only - to make sure the transfer optimization really 1531 ** is happening when it is suppose to. 1532 */ 1533 int sqlite3_xferopt_count; 1534 #endif /* SQLITE_TEST */ 1535 1536 1537 #ifndef SQLITE_OMIT_XFER_OPT 1538 /* 1539 ** Check to collation names to see if they are compatible. 1540 */ 1541 static int xferCompatibleCollation(const char *z1, const char *z2){ 1542 if( z1==0 ){ 1543 return z2==0; 1544 } 1545 if( z2==0 ){ 1546 return 0; 1547 } 1548 return sqlite3StrICmp(z1, z2)==0; 1549 } 1550 1551 1552 /* 1553 ** Check to see if index pSrc is compatible as a source of data 1554 ** for index pDest in an insert transfer optimization. The rules 1555 ** for a compatible index: 1556 ** 1557 ** * The index is over the same set of columns 1558 ** * The same DESC and ASC markings occurs on all columns 1559 ** * The same onError processing (OE_Abort, OE_Ignore, etc) 1560 ** * The same collating sequence on each column 1561 */ 1562 static int xferCompatibleIndex(Index *pDest, Index *pSrc){ 1563 int i; 1564 assert( pDest && pSrc ); 1565 assert( pDest->pTable!=pSrc->pTable ); 1566 if( pDest->nColumn!=pSrc->nColumn ){ 1567 return 0; /* Different number of columns */ 1568 } 1569 if( pDest->onError!=pSrc->onError ){ 1570 return 0; /* Different conflict resolution strategies */ 1571 } 1572 for(i=0; i<pSrc->nColumn; i++){ 1573 if( pSrc->aiColumn[i]!=pDest->aiColumn[i] ){ 1574 return 0; /* Different columns indexed */ 1575 } 1576 if( pSrc->aSortOrder[i]!=pDest->aSortOrder[i] ){ 1577 return 0; /* Different sort orders */ 1578 } 1579 if( !xferCompatibleCollation(pSrc->azColl[i],pDest->azColl[i]) ){ 1580 return 0; /* Different collating sequences */ 1581 } 1582 } 1583 1584 /* If no test above fails then the indices must be compatible */ 1585 return 1; 1586 } 1587 1588 /* 1589 ** Attempt the transfer optimization on INSERTs of the form 1590 ** 1591 ** INSERT INTO tab1 SELECT * FROM tab2; 1592 ** 1593 ** The xfer optimization transfers raw records from tab2 over to tab1. 1594 ** Columns are not decoded and reassemblied, which greatly improves 1595 ** performance. Raw index records are transferred in the same way. 1596 ** 1597 ** The xfer optimization is only attempted if tab1 and tab2 are compatible. 1598 ** There are lots of rules for determining compatibility - see comments 1599 ** embedded in the code for details. 1600 ** 1601 ** This routine returns TRUE if the optimization is guaranteed to be used. 1602 ** Sometimes the xfer optimization will only work if the destination table 1603 ** is empty - a factor that can only be determined at run-time. In that 1604 ** case, this routine generates code for the xfer optimization but also 1605 ** does a test to see if the destination table is empty and jumps over the 1606 ** xfer optimization code if the test fails. In that case, this routine 1607 ** returns FALSE so that the caller will know to go ahead and generate 1608 ** an unoptimized transfer. This routine also returns FALSE if there 1609 ** is no chance that the xfer optimization can be applied. 1610 ** 1611 ** This optimization is particularly useful at making VACUUM run faster. 1612 */ 1613 static int xferOptimization( 1614 Parse *pParse, /* Parser context */ 1615 Table *pDest, /* The table we are inserting into */ 1616 Select *pSelect, /* A SELECT statement to use as the data source */ 1617 int onError, /* How to handle constraint errors */ 1618 int iDbDest /* The database of pDest */ 1619 ){ 1620 ExprList *pEList; /* The result set of the SELECT */ 1621 Table *pSrc; /* The table in the FROM clause of SELECT */ 1622 Index *pSrcIdx, *pDestIdx; /* Source and destination indices */ 1623 struct SrcList_item *pItem; /* An element of pSelect->pSrc */ 1624 int i; /* Loop counter */ 1625 int iDbSrc; /* The database of pSrc */ 1626 int iSrc, iDest; /* Cursors from source and destination */ 1627 int addr1, addr2; /* Loop addresses */ 1628 int emptyDestTest; /* Address of test for empty pDest */ 1629 int emptySrcTest; /* Address of test for empty pSrc */ 1630 Vdbe *v; /* The VDBE we are building */ 1631 KeyInfo *pKey; /* Key information for an index */ 1632 int regAutoinc; /* Memory register used by AUTOINC */ 1633 int destHasUniqueIdx = 0; /* True if pDest has a UNIQUE index */ 1634 int regData, regRowid; /* Registers holding data and rowid */ 1635 1636 if( pSelect==0 ){ 1637 return 0; /* Must be of the form INSERT INTO ... SELECT ... */ 1638 } 1639 if( sqlite3TriggerList(pParse, pDest) ){ 1640 return 0; /* tab1 must not have triggers */ 1641 } 1642 #ifndef SQLITE_OMIT_VIRTUALTABLE 1643 if( pDest->tabFlags & TF_Virtual ){ 1644 return 0; /* tab1 must not be a virtual table */ 1645 } 1646 #endif 1647 if( onError==OE_Default ){ 1648 if( pDest->iPKey>=0 ) onError = pDest->keyConf; 1649 if( onError==OE_Default ) onError = OE_Abort; 1650 } 1651 assert(pSelect->pSrc); /* allocated even if there is no FROM clause */ 1652 if( pSelect->pSrc->nSrc!=1 ){ 1653 return 0; /* FROM clause must have exactly one term */ 1654 } 1655 if( pSelect->pSrc->a[0].pSelect ){ 1656 return 0; /* FROM clause cannot contain a subquery */ 1657 } 1658 if( pSelect->pWhere ){ 1659 return 0; /* SELECT may not have a WHERE clause */ 1660 } 1661 if( pSelect->pOrderBy ){ 1662 return 0; /* SELECT may not have an ORDER BY clause */ 1663 } 1664 /* Do not need to test for a HAVING clause. If HAVING is present but 1665 ** there is no ORDER BY, we will get an error. */ 1666 if( pSelect->pGroupBy ){ 1667 return 0; /* SELECT may not have a GROUP BY clause */ 1668 } 1669 if( pSelect->pLimit ){ 1670 return 0; /* SELECT may not have a LIMIT clause */ 1671 } 1672 assert( pSelect->pOffset==0 ); /* Must be so if pLimit==0 */ 1673 if( pSelect->pPrior ){ 1674 return 0; /* SELECT may not be a compound query */ 1675 } 1676 if( pSelect->selFlags & SF_Distinct ){ 1677 return 0; /* SELECT may not be DISTINCT */ 1678 } 1679 pEList = pSelect->pEList; 1680 assert( pEList!=0 ); 1681 if( pEList->nExpr!=1 ){ 1682 return 0; /* The result set must have exactly one column */ 1683 } 1684 assert( pEList->a[0].pExpr ); 1685 if( pEList->a[0].pExpr->op!=TK_ALL ){ 1686 return 0; /* The result set must be the special operator "*" */ 1687 } 1688 1689 /* At this point we have established that the statement is of the 1690 ** correct syntactic form to participate in this optimization. Now 1691 ** we have to check the semantics. 1692 */ 1693 pItem = pSelect->pSrc->a; 1694 pSrc = sqlite3LocateTable(pParse, 0, pItem->zName, pItem->zDatabase); 1695 if( pSrc==0 ){ 1696 return 0; /* FROM clause does not contain a real table */ 1697 } 1698 if( pSrc==pDest ){ 1699 return 0; /* tab1 and tab2 may not be the same table */ 1700 } 1701 #ifndef SQLITE_OMIT_VIRTUALTABLE 1702 if( pSrc->tabFlags & TF_Virtual ){ 1703 return 0; /* tab2 must not be a virtual table */ 1704 } 1705 #endif 1706 if( pSrc->pSelect ){ 1707 return 0; /* tab2 may not be a view */ 1708 } 1709 if( pDest->nCol!=pSrc->nCol ){ 1710 return 0; /* Number of columns must be the same in tab1 and tab2 */ 1711 } 1712 if( pDest->iPKey!=pSrc->iPKey ){ 1713 return 0; /* Both tables must have the same INTEGER PRIMARY KEY */ 1714 } 1715 for(i=0; i<pDest->nCol; i++){ 1716 if( pDest->aCol[i].affinity!=pSrc->aCol[i].affinity ){ 1717 return 0; /* Affinity must be the same on all columns */ 1718 } 1719 if( !xferCompatibleCollation(pDest->aCol[i].zColl, pSrc->aCol[i].zColl) ){ 1720 return 0; /* Collating sequence must be the same on all columns */ 1721 } 1722 if( pDest->aCol[i].notNull && !pSrc->aCol[i].notNull ){ 1723 return 0; /* tab2 must be NOT NULL if tab1 is */ 1724 } 1725 } 1726 for(pDestIdx=pDest->pIndex; pDestIdx; pDestIdx=pDestIdx->pNext){ 1727 if( pDestIdx->onError!=OE_None ){ 1728 destHasUniqueIdx = 1; 1729 } 1730 for(pSrcIdx=pSrc->pIndex; pSrcIdx; pSrcIdx=pSrcIdx->pNext){ 1731 if( xferCompatibleIndex(pDestIdx, pSrcIdx) ) break; 1732 } 1733 if( pSrcIdx==0 ){ 1734 return 0; /* pDestIdx has no corresponding index in pSrc */ 1735 } 1736 } 1737 #ifndef SQLITE_OMIT_CHECK 1738 if( pDest->pCheck && sqlite3ExprListCompare(pSrc->pCheck, pDest->pCheck) ){ 1739 return 0; /* Tables have different CHECK constraints. Ticket #2252 */ 1740 } 1741 #endif 1742 #ifndef SQLITE_OMIT_FOREIGN_KEY 1743 /* Disallow the transfer optimization if the destination table constains 1744 ** any foreign key constraints. This is more restrictive than necessary. 1745 ** But the main beneficiary of the transfer optimization is the VACUUM 1746 ** command, and the VACUUM command disables foreign key constraints. So 1747 ** the extra complication to make this rule less restrictive is probably 1748 ** not worth the effort. Ticket [6284df89debdfa61db8073e062908af0c9b6118e] 1749 */ 1750 if( (pParse->db->flags & SQLITE_ForeignKeys)!=0 && pDest->pFKey!=0 ){ 1751 return 0; 1752 } 1753 #endif 1754 if( (pParse->db->flags & SQLITE_CountRows)!=0 ){ 1755 return 0; /* xfer opt does not play well with PRAGMA count_changes */ 1756 } 1757 1758 /* If we get this far, it means that the xfer optimization is at 1759 ** least a possibility, though it might only work if the destination 1760 ** table (tab1) is initially empty. 1761 */ 1762 #ifdef SQLITE_TEST 1763 sqlite3_xferopt_count++; 1764 #endif 1765 iDbSrc = sqlite3SchemaToIndex(pParse->db, pSrc->pSchema); 1766 v = sqlite3GetVdbe(pParse); 1767 sqlite3CodeVerifySchema(pParse, iDbSrc); 1768 iSrc = pParse->nTab++; 1769 iDest = pParse->nTab++; 1770 regAutoinc = autoIncBegin(pParse, iDbDest, pDest); 1771 sqlite3OpenTable(pParse, iDest, iDbDest, pDest, OP_OpenWrite); 1772 if( (pDest->iPKey<0 && pDest->pIndex!=0) /* (1) */ 1773 || destHasUniqueIdx /* (2) */ 1774 || (onError!=OE_Abort && onError!=OE_Rollback) /* (3) */ 1775 ){ 1776 /* In some circumstances, we are able to run the xfer optimization 1777 ** only if the destination table is initially empty. This code makes 1778 ** that determination. Conditions under which the destination must 1779 ** be empty: 1780 ** 1781 ** (1) There is no INTEGER PRIMARY KEY but there are indices. 1782 ** (If the destination is not initially empty, the rowid fields 1783 ** of index entries might need to change.) 1784 ** 1785 ** (2) The destination has a unique index. (The xfer optimization 1786 ** is unable to test uniqueness.) 1787 ** 1788 ** (3) onError is something other than OE_Abort and OE_Rollback. 1789 */ 1790 addr1 = sqlite3VdbeAddOp2(v, OP_Rewind, iDest, 0); 1791 emptyDestTest = sqlite3VdbeAddOp2(v, OP_Goto, 0, 0); 1792 sqlite3VdbeJumpHere(v, addr1); 1793 }else{ 1794 emptyDestTest = 0; 1795 } 1796 sqlite3OpenTable(pParse, iSrc, iDbSrc, pSrc, OP_OpenRead); 1797 emptySrcTest = sqlite3VdbeAddOp2(v, OP_Rewind, iSrc, 0); 1798 regData = sqlite3GetTempReg(pParse); 1799 regRowid = sqlite3GetTempReg(pParse); 1800 if( pDest->iPKey>=0 ){ 1801 addr1 = sqlite3VdbeAddOp2(v, OP_Rowid, iSrc, regRowid); 1802 addr2 = sqlite3VdbeAddOp3(v, OP_NotExists, iDest, 0, regRowid); 1803 sqlite3HaltConstraint( 1804 pParse, onError, "PRIMARY KEY must be unique", P4_STATIC); 1805 sqlite3VdbeJumpHere(v, addr2); 1806 autoIncStep(pParse, regAutoinc, regRowid); 1807 }else if( pDest->pIndex==0 ){ 1808 addr1 = sqlite3VdbeAddOp2(v, OP_NewRowid, iDest, regRowid); 1809 }else{ 1810 addr1 = sqlite3VdbeAddOp2(v, OP_Rowid, iSrc, regRowid); 1811 assert( (pDest->tabFlags & TF_Autoincrement)==0 ); 1812 } 1813 sqlite3VdbeAddOp2(v, OP_RowData, iSrc, regData); 1814 sqlite3VdbeAddOp3(v, OP_Insert, iDest, regData, regRowid); 1815 sqlite3VdbeChangeP5(v, OPFLAG_NCHANGE|OPFLAG_LASTROWID|OPFLAG_APPEND); 1816 sqlite3VdbeChangeP4(v, -1, pDest->zName, 0); 1817 sqlite3VdbeAddOp2(v, OP_Next, iSrc, addr1); 1818 for(pDestIdx=pDest->pIndex; pDestIdx; pDestIdx=pDestIdx->pNext){ 1819 for(pSrcIdx=pSrc->pIndex; ALWAYS(pSrcIdx); pSrcIdx=pSrcIdx->pNext){ 1820 if( xferCompatibleIndex(pDestIdx, pSrcIdx) ) break; 1821 } 1822 assert( pSrcIdx ); 1823 sqlite3VdbeAddOp2(v, OP_Close, iSrc, 0); 1824 sqlite3VdbeAddOp2(v, OP_Close, iDest, 0); 1825 pKey = sqlite3IndexKeyinfo(pParse, pSrcIdx); 1826 sqlite3VdbeAddOp4(v, OP_OpenRead, iSrc, pSrcIdx->tnum, iDbSrc, 1827 (char*)pKey, P4_KEYINFO_HANDOFF); 1828 VdbeComment((v, "%s", pSrcIdx->zName)); 1829 pKey = sqlite3IndexKeyinfo(pParse, pDestIdx); 1830 sqlite3VdbeAddOp4(v, OP_OpenWrite, iDest, pDestIdx->tnum, iDbDest, 1831 (char*)pKey, P4_KEYINFO_HANDOFF); 1832 VdbeComment((v, "%s", pDestIdx->zName)); 1833 addr1 = sqlite3VdbeAddOp2(v, OP_Rewind, iSrc, 0); 1834 sqlite3VdbeAddOp2(v, OP_RowKey, iSrc, regData); 1835 sqlite3VdbeAddOp3(v, OP_IdxInsert, iDest, regData, 1); 1836 sqlite3VdbeAddOp2(v, OP_Next, iSrc, addr1+1); 1837 sqlite3VdbeJumpHere(v, addr1); 1838 } 1839 sqlite3VdbeJumpHere(v, emptySrcTest); 1840 sqlite3ReleaseTempReg(pParse, regRowid); 1841 sqlite3ReleaseTempReg(pParse, regData); 1842 sqlite3VdbeAddOp2(v, OP_Close, iSrc, 0); 1843 sqlite3VdbeAddOp2(v, OP_Close, iDest, 0); 1844 if( emptyDestTest ){ 1845 sqlite3VdbeAddOp2(v, OP_Halt, SQLITE_OK, 0); 1846 sqlite3VdbeJumpHere(v, emptyDestTest); 1847 sqlite3VdbeAddOp2(v, OP_Close, iDest, 0); 1848 return 0; 1849 }else{ 1850 return 1; 1851 } 1852 } 1853 #endif /* SQLITE_OMIT_XFER_OPT */ 1854