000001 /* 000002 ** 2001 September 15 000003 ** 000004 ** The author disclaims copyright to this source code. In place of 000005 ** a legal notice, here is a blessing: 000006 ** 000007 ** May you do good and not evil. 000008 ** May you find forgiveness for yourself and forgive others. 000009 ** May you share freely, never taking more than you give. 000010 ** 000011 ************************************************************************* 000012 ** This file contains routines used for analyzing expressions and 000013 ** for generating VDBE code that evaluates expressions in SQLite. 000014 */ 000015 #include "sqliteInt.h" 000016 000017 /* Forward declarations */ 000018 static void exprCodeBetween(Parse*,Expr*,int,void(*)(Parse*,Expr*,int,int),int); 000019 static int exprCodeVector(Parse *pParse, Expr *p, int *piToFree); 000020 000021 /* 000022 ** Return the affinity character for a single column of a table. 000023 */ 000024 char sqlite3TableColumnAffinity(Table *pTab, int iCol){ 000025 assert( iCol<pTab->nCol ); 000026 return iCol>=0 ? pTab->aCol[iCol].affinity : SQLITE_AFF_INTEGER; 000027 } 000028 000029 /* 000030 ** Return the 'affinity' of the expression pExpr if any. 000031 ** 000032 ** If pExpr is a column, a reference to a column via an 'AS' alias, 000033 ** or a sub-select with a column as the return value, then the 000034 ** affinity of that column is returned. Otherwise, 0x00 is returned, 000035 ** indicating no affinity for the expression. 000036 ** 000037 ** i.e. the WHERE clause expressions in the following statements all 000038 ** have an affinity: 000039 ** 000040 ** CREATE TABLE t1(a); 000041 ** SELECT * FROM t1 WHERE a; 000042 ** SELECT a AS b FROM t1 WHERE b; 000043 ** SELECT * FROM t1 WHERE (select a from t1); 000044 */ 000045 char sqlite3ExprAffinity(Expr *pExpr){ 000046 int op; 000047 while( ExprHasProperty(pExpr, EP_Skip) ){ 000048 assert( pExpr->op==TK_COLLATE ); 000049 pExpr = pExpr->pLeft; 000050 assert( pExpr!=0 ); 000051 } 000052 op = pExpr->op; 000053 if( op==TK_SELECT ){ 000054 assert( pExpr->flags&EP_xIsSelect ); 000055 return sqlite3ExprAffinity(pExpr->x.pSelect->pEList->a[0].pExpr); 000056 } 000057 if( op==TK_REGISTER ) op = pExpr->op2; 000058 #ifndef SQLITE_OMIT_CAST 000059 if( op==TK_CAST ){ 000060 assert( !ExprHasProperty(pExpr, EP_IntValue) ); 000061 return sqlite3AffinityType(pExpr->u.zToken, 0); 000062 } 000063 #endif 000064 if( (op==TK_AGG_COLUMN || op==TK_COLUMN) && pExpr->y.pTab ){ 000065 return sqlite3TableColumnAffinity(pExpr->y.pTab, pExpr->iColumn); 000066 } 000067 if( op==TK_SELECT_COLUMN ){ 000068 assert( pExpr->pLeft->flags&EP_xIsSelect ); 000069 return sqlite3ExprAffinity( 000070 pExpr->pLeft->x.pSelect->pEList->a[pExpr->iColumn].pExpr 000071 ); 000072 } 000073 if( op==TK_VECTOR ){ 000074 return sqlite3ExprAffinity(pExpr->x.pList->a[0].pExpr); 000075 } 000076 return pExpr->affExpr; 000077 } 000078 000079 /* 000080 ** Set the collating sequence for expression pExpr to be the collating 000081 ** sequence named by pToken. Return a pointer to a new Expr node that 000082 ** implements the COLLATE operator. 000083 ** 000084 ** If a memory allocation error occurs, that fact is recorded in pParse->db 000085 ** and the pExpr parameter is returned unchanged. 000086 */ 000087 Expr *sqlite3ExprAddCollateToken( 000088 Parse *pParse, /* Parsing context */ 000089 Expr *pExpr, /* Add the "COLLATE" clause to this expression */ 000090 const Token *pCollName, /* Name of collating sequence */ 000091 int dequote /* True to dequote pCollName */ 000092 ){ 000093 if( pCollName->n>0 ){ 000094 Expr *pNew = sqlite3ExprAlloc(pParse->db, TK_COLLATE, pCollName, dequote); 000095 if( pNew ){ 000096 pNew->pLeft = pExpr; 000097 pNew->flags |= EP_Collate|EP_Skip; 000098 pExpr = pNew; 000099 } 000100 } 000101 return pExpr; 000102 } 000103 Expr *sqlite3ExprAddCollateString(Parse *pParse, Expr *pExpr, const char *zC){ 000104 Token s; 000105 assert( zC!=0 ); 000106 sqlite3TokenInit(&s, (char*)zC); 000107 return sqlite3ExprAddCollateToken(pParse, pExpr, &s, 0); 000108 } 000109 000110 /* 000111 ** Skip over any TK_COLLATE operators. 000112 */ 000113 Expr *sqlite3ExprSkipCollate(Expr *pExpr){ 000114 while( pExpr && ExprHasProperty(pExpr, EP_Skip) ){ 000115 assert( pExpr->op==TK_COLLATE ); 000116 pExpr = pExpr->pLeft; 000117 } 000118 return pExpr; 000119 } 000120 000121 /* 000122 ** Skip over any TK_COLLATE operators and/or any unlikely() 000123 ** or likelihood() or likely() functions at the root of an 000124 ** expression. 000125 */ 000126 Expr *sqlite3ExprSkipCollateAndLikely(Expr *pExpr){ 000127 while( pExpr && ExprHasProperty(pExpr, EP_Skip|EP_Unlikely) ){ 000128 if( ExprHasProperty(pExpr, EP_Unlikely) ){ 000129 assert( !ExprHasProperty(pExpr, EP_xIsSelect) ); 000130 assert( pExpr->x.pList->nExpr>0 ); 000131 assert( pExpr->op==TK_FUNCTION ); 000132 pExpr = pExpr->x.pList->a[0].pExpr; 000133 }else{ 000134 assert( pExpr->op==TK_COLLATE ); 000135 pExpr = pExpr->pLeft; 000136 } 000137 } 000138 return pExpr; 000139 } 000140 000141 /* 000142 ** Return the collation sequence for the expression pExpr. If 000143 ** there is no defined collating sequence, return NULL. 000144 ** 000145 ** See also: sqlite3ExprNNCollSeq() 000146 ** 000147 ** The sqlite3ExprNNCollSeq() works the same exact that it returns the 000148 ** default collation if pExpr has no defined collation. 000149 ** 000150 ** The collating sequence might be determined by a COLLATE operator 000151 ** or by the presence of a column with a defined collating sequence. 000152 ** COLLATE operators take first precedence. Left operands take 000153 ** precedence over right operands. 000154 */ 000155 CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr){ 000156 sqlite3 *db = pParse->db; 000157 CollSeq *pColl = 0; 000158 Expr *p = pExpr; 000159 while( p ){ 000160 int op = p->op; 000161 if( op==TK_REGISTER ) op = p->op2; 000162 if( (op==TK_AGG_COLUMN || op==TK_COLUMN || op==TK_TRIGGER) 000163 && p->y.pTab!=0 000164 ){ 000165 /* op==TK_REGISTER && p->y.pTab!=0 happens when pExpr was originally 000166 ** a TK_COLUMN but was previously evaluated and cached in a register */ 000167 int j = p->iColumn; 000168 if( j>=0 ){ 000169 const char *zColl = p->y.pTab->aCol[j].zColl; 000170 pColl = sqlite3FindCollSeq(db, ENC(db), zColl, 0); 000171 } 000172 break; 000173 } 000174 if( op==TK_CAST || op==TK_UPLUS ){ 000175 p = p->pLeft; 000176 continue; 000177 } 000178 if( op==TK_VECTOR ){ 000179 p = p->x.pList->a[0].pExpr; 000180 continue; 000181 } 000182 if( op==TK_COLLATE ){ 000183 pColl = sqlite3GetCollSeq(pParse, ENC(db), 0, p->u.zToken); 000184 break; 000185 } 000186 if( p->flags & EP_Collate ){ 000187 if( p->pLeft && (p->pLeft->flags & EP_Collate)!=0 ){ 000188 p = p->pLeft; 000189 }else{ 000190 Expr *pNext = p->pRight; 000191 /* The Expr.x union is never used at the same time as Expr.pRight */ 000192 assert( p->x.pList==0 || p->pRight==0 ); 000193 if( p->x.pList!=0 000194 && !db->mallocFailed 000195 && ALWAYS(!ExprHasProperty(p, EP_xIsSelect)) 000196 ){ 000197 int i; 000198 for(i=0; i<p->x.pList->nExpr; i++){ 000199 if( ExprHasProperty(p->x.pList->a[i].pExpr, EP_Collate) ){ 000200 pNext = p->x.pList->a[i].pExpr; 000201 break; 000202 } 000203 } 000204 } 000205 p = pNext; 000206 } 000207 }else{ 000208 break; 000209 } 000210 } 000211 if( sqlite3CheckCollSeq(pParse, pColl) ){ 000212 pColl = 0; 000213 } 000214 return pColl; 000215 } 000216 000217 /* 000218 ** Return the collation sequence for the expression pExpr. If 000219 ** there is no defined collating sequence, return a pointer to the 000220 ** defautl collation sequence. 000221 ** 000222 ** See also: sqlite3ExprCollSeq() 000223 ** 000224 ** The sqlite3ExprCollSeq() routine works the same except that it 000225 ** returns NULL if there is no defined collation. 000226 */ 000227 CollSeq *sqlite3ExprNNCollSeq(Parse *pParse, Expr *pExpr){ 000228 CollSeq *p = sqlite3ExprCollSeq(pParse, pExpr); 000229 if( p==0 ) p = pParse->db->pDfltColl; 000230 assert( p!=0 ); 000231 return p; 000232 } 000233 000234 /* 000235 ** Return TRUE if the two expressions have equivalent collating sequences. 000236 */ 000237 int sqlite3ExprCollSeqMatch(Parse *pParse, Expr *pE1, Expr *pE2){ 000238 CollSeq *pColl1 = sqlite3ExprNNCollSeq(pParse, pE1); 000239 CollSeq *pColl2 = sqlite3ExprNNCollSeq(pParse, pE2); 000240 return sqlite3StrICmp(pColl1->zName, pColl2->zName)==0; 000241 } 000242 000243 /* 000244 ** pExpr is an operand of a comparison operator. aff2 is the 000245 ** type affinity of the other operand. This routine returns the 000246 ** type affinity that should be used for the comparison operator. 000247 */ 000248 char sqlite3CompareAffinity(Expr *pExpr, char aff2){ 000249 char aff1 = sqlite3ExprAffinity(pExpr); 000250 if( aff1>SQLITE_AFF_NONE && aff2>SQLITE_AFF_NONE ){ 000251 /* Both sides of the comparison are columns. If one has numeric 000252 ** affinity, use that. Otherwise use no affinity. 000253 */ 000254 if( sqlite3IsNumericAffinity(aff1) || sqlite3IsNumericAffinity(aff2) ){ 000255 return SQLITE_AFF_NUMERIC; 000256 }else{ 000257 return SQLITE_AFF_BLOB; 000258 } 000259 }else{ 000260 /* One side is a column, the other is not. Use the columns affinity. */ 000261 assert( aff1<=SQLITE_AFF_NONE || aff2<=SQLITE_AFF_NONE ); 000262 return (aff1<=SQLITE_AFF_NONE ? aff2 : aff1) | SQLITE_AFF_NONE; 000263 } 000264 } 000265 000266 /* 000267 ** pExpr is a comparison operator. Return the type affinity that should 000268 ** be applied to both operands prior to doing the comparison. 000269 */ 000270 static char comparisonAffinity(Expr *pExpr){ 000271 char aff; 000272 assert( pExpr->op==TK_EQ || pExpr->op==TK_IN || pExpr->op==TK_LT || 000273 pExpr->op==TK_GT || pExpr->op==TK_GE || pExpr->op==TK_LE || 000274 pExpr->op==TK_NE || pExpr->op==TK_IS || pExpr->op==TK_ISNOT ); 000275 assert( pExpr->pLeft ); 000276 aff = sqlite3ExprAffinity(pExpr->pLeft); 000277 if( pExpr->pRight ){ 000278 aff = sqlite3CompareAffinity(pExpr->pRight, aff); 000279 }else if( ExprHasProperty(pExpr, EP_xIsSelect) ){ 000280 aff = sqlite3CompareAffinity(pExpr->x.pSelect->pEList->a[0].pExpr, aff); 000281 }else if( aff==0 ){ 000282 aff = SQLITE_AFF_BLOB; 000283 } 000284 return aff; 000285 } 000286 000287 /* 000288 ** pExpr is a comparison expression, eg. '=', '<', IN(...) etc. 000289 ** idx_affinity is the affinity of an indexed column. Return true 000290 ** if the index with affinity idx_affinity may be used to implement 000291 ** the comparison in pExpr. 000292 */ 000293 int sqlite3IndexAffinityOk(Expr *pExpr, char idx_affinity){ 000294 char aff = comparisonAffinity(pExpr); 000295 if( aff<SQLITE_AFF_TEXT ){ 000296 return 1; 000297 } 000298 if( aff==SQLITE_AFF_TEXT ){ 000299 return idx_affinity==SQLITE_AFF_TEXT; 000300 } 000301 return sqlite3IsNumericAffinity(idx_affinity); 000302 } 000303 000304 /* 000305 ** Return the P5 value that should be used for a binary comparison 000306 ** opcode (OP_Eq, OP_Ge etc.) used to compare pExpr1 and pExpr2. 000307 */ 000308 static u8 binaryCompareP5(Expr *pExpr1, Expr *pExpr2, int jumpIfNull){ 000309 u8 aff = (char)sqlite3ExprAffinity(pExpr2); 000310 aff = (u8)sqlite3CompareAffinity(pExpr1, aff) | (u8)jumpIfNull; 000311 return aff; 000312 } 000313 000314 /* 000315 ** Return a pointer to the collation sequence that should be used by 000316 ** a binary comparison operator comparing pLeft and pRight. 000317 ** 000318 ** If the left hand expression has a collating sequence type, then it is 000319 ** used. Otherwise the collation sequence for the right hand expression 000320 ** is used, or the default (BINARY) if neither expression has a collating 000321 ** type. 000322 ** 000323 ** Argument pRight (but not pLeft) may be a null pointer. In this case, 000324 ** it is not considered. 000325 */ 000326 CollSeq *sqlite3BinaryCompareCollSeq( 000327 Parse *pParse, 000328 Expr *pLeft, 000329 Expr *pRight 000330 ){ 000331 CollSeq *pColl; 000332 assert( pLeft ); 000333 if( pLeft->flags & EP_Collate ){ 000334 pColl = sqlite3ExprCollSeq(pParse, pLeft); 000335 }else if( pRight && (pRight->flags & EP_Collate)!=0 ){ 000336 pColl = sqlite3ExprCollSeq(pParse, pRight); 000337 }else{ 000338 pColl = sqlite3ExprCollSeq(pParse, pLeft); 000339 if( !pColl ){ 000340 pColl = sqlite3ExprCollSeq(pParse, pRight); 000341 } 000342 } 000343 return pColl; 000344 } 000345 000346 /* Expresssion p is a comparison operator. Return a collation sequence 000347 ** appropriate for the comparison operator. 000348 ** 000349 ** This is normally just a wrapper around sqlite3BinaryCompareCollSeq(). 000350 ** However, if the OP_Commuted flag is set, then the order of the operands 000351 ** is reversed in the sqlite3BinaryCompareCollSeq() call so that the 000352 ** correct collating sequence is found. 000353 */ 000354 CollSeq *sqlite3ExprCompareCollSeq(Parse *pParse, Expr *p){ 000355 if( ExprHasProperty(p, EP_Commuted) ){ 000356 return sqlite3BinaryCompareCollSeq(pParse, p->pRight, p->pLeft); 000357 }else{ 000358 return sqlite3BinaryCompareCollSeq(pParse, p->pLeft, p->pRight); 000359 } 000360 } 000361 000362 /* 000363 ** Generate code for a comparison operator. 000364 */ 000365 static int codeCompare( 000366 Parse *pParse, /* The parsing (and code generating) context */ 000367 Expr *pLeft, /* The left operand */ 000368 Expr *pRight, /* The right operand */ 000369 int opcode, /* The comparison opcode */ 000370 int in1, int in2, /* Register holding operands */ 000371 int dest, /* Jump here if true. */ 000372 int jumpIfNull, /* If true, jump if either operand is NULL */ 000373 int isCommuted /* The comparison has been commuted */ 000374 ){ 000375 int p5; 000376 int addr; 000377 CollSeq *p4; 000378 000379 if( pParse->nErr ) return 0; 000380 if( isCommuted ){ 000381 p4 = sqlite3BinaryCompareCollSeq(pParse, pRight, pLeft); 000382 }else{ 000383 p4 = sqlite3BinaryCompareCollSeq(pParse, pLeft, pRight); 000384 } 000385 p5 = binaryCompareP5(pLeft, pRight, jumpIfNull); 000386 addr = sqlite3VdbeAddOp4(pParse->pVdbe, opcode, in2, dest, in1, 000387 (void*)p4, P4_COLLSEQ); 000388 sqlite3VdbeChangeP5(pParse->pVdbe, (u8)p5); 000389 return addr; 000390 } 000391 000392 /* 000393 ** Return true if expression pExpr is a vector, or false otherwise. 000394 ** 000395 ** A vector is defined as any expression that results in two or more 000396 ** columns of result. Every TK_VECTOR node is an vector because the 000397 ** parser will not generate a TK_VECTOR with fewer than two entries. 000398 ** But a TK_SELECT might be either a vector or a scalar. It is only 000399 ** considered a vector if it has two or more result columns. 000400 */ 000401 int sqlite3ExprIsVector(Expr *pExpr){ 000402 return sqlite3ExprVectorSize(pExpr)>1; 000403 } 000404 000405 /* 000406 ** If the expression passed as the only argument is of type TK_VECTOR 000407 ** return the number of expressions in the vector. Or, if the expression 000408 ** is a sub-select, return the number of columns in the sub-select. For 000409 ** any other type of expression, return 1. 000410 */ 000411 int sqlite3ExprVectorSize(Expr *pExpr){ 000412 u8 op = pExpr->op; 000413 if( op==TK_REGISTER ) op = pExpr->op2; 000414 if( op==TK_VECTOR ){ 000415 return pExpr->x.pList->nExpr; 000416 }else if( op==TK_SELECT ){ 000417 return pExpr->x.pSelect->pEList->nExpr; 000418 }else{ 000419 return 1; 000420 } 000421 } 000422 000423 /* 000424 ** Return a pointer to a subexpression of pVector that is the i-th 000425 ** column of the vector (numbered starting with 0). The caller must 000426 ** ensure that i is within range. 000427 ** 000428 ** If pVector is really a scalar (and "scalar" here includes subqueries 000429 ** that return a single column!) then return pVector unmodified. 000430 ** 000431 ** pVector retains ownership of the returned subexpression. 000432 ** 000433 ** If the vector is a (SELECT ...) then the expression returned is 000434 ** just the expression for the i-th term of the result set, and may 000435 ** not be ready for evaluation because the table cursor has not yet 000436 ** been positioned. 000437 */ 000438 Expr *sqlite3VectorFieldSubexpr(Expr *pVector, int i){ 000439 assert( i<sqlite3ExprVectorSize(pVector) ); 000440 if( sqlite3ExprIsVector(pVector) ){ 000441 assert( pVector->op2==0 || pVector->op==TK_REGISTER ); 000442 if( pVector->op==TK_SELECT || pVector->op2==TK_SELECT ){ 000443 return pVector->x.pSelect->pEList->a[i].pExpr; 000444 }else{ 000445 return pVector->x.pList->a[i].pExpr; 000446 } 000447 } 000448 return pVector; 000449 } 000450 000451 /* 000452 ** Compute and return a new Expr object which when passed to 000453 ** sqlite3ExprCode() will generate all necessary code to compute 000454 ** the iField-th column of the vector expression pVector. 000455 ** 000456 ** It is ok for pVector to be a scalar (as long as iField==0). 000457 ** In that case, this routine works like sqlite3ExprDup(). 000458 ** 000459 ** The caller owns the returned Expr object and is responsible for 000460 ** ensuring that the returned value eventually gets freed. 000461 ** 000462 ** The caller retains ownership of pVector. If pVector is a TK_SELECT, 000463 ** then the returned object will reference pVector and so pVector must remain 000464 ** valid for the life of the returned object. If pVector is a TK_VECTOR 000465 ** or a scalar expression, then it can be deleted as soon as this routine 000466 ** returns. 000467 ** 000468 ** A trick to cause a TK_SELECT pVector to be deleted together with 000469 ** the returned Expr object is to attach the pVector to the pRight field 000470 ** of the returned TK_SELECT_COLUMN Expr object. 000471 */ 000472 Expr *sqlite3ExprForVectorField( 000473 Parse *pParse, /* Parsing context */ 000474 Expr *pVector, /* The vector. List of expressions or a sub-SELECT */ 000475 int iField /* Which column of the vector to return */ 000476 ){ 000477 Expr *pRet; 000478 if( pVector->op==TK_SELECT ){ 000479 assert( pVector->flags & EP_xIsSelect ); 000480 /* The TK_SELECT_COLUMN Expr node: 000481 ** 000482 ** pLeft: pVector containing TK_SELECT. Not deleted. 000483 ** pRight: not used. But recursively deleted. 000484 ** iColumn: Index of a column in pVector 000485 ** iTable: 0 or the number of columns on the LHS of an assignment 000486 ** pLeft->iTable: First in an array of register holding result, or 0 000487 ** if the result is not yet computed. 000488 ** 000489 ** sqlite3ExprDelete() specifically skips the recursive delete of 000490 ** pLeft on TK_SELECT_COLUMN nodes. But pRight is followed, so pVector 000491 ** can be attached to pRight to cause this node to take ownership of 000492 ** pVector. Typically there will be multiple TK_SELECT_COLUMN nodes 000493 ** with the same pLeft pointer to the pVector, but only one of them 000494 ** will own the pVector. 000495 */ 000496 pRet = sqlite3PExpr(pParse, TK_SELECT_COLUMN, 0, 0); 000497 if( pRet ){ 000498 pRet->iColumn = iField; 000499 pRet->pLeft = pVector; 000500 } 000501 assert( pRet==0 || pRet->iTable==0 ); 000502 }else{ 000503 if( pVector->op==TK_VECTOR ) pVector = pVector->x.pList->a[iField].pExpr; 000504 pRet = sqlite3ExprDup(pParse->db, pVector, 0); 000505 sqlite3RenameTokenRemap(pParse, pRet, pVector); 000506 } 000507 return pRet; 000508 } 000509 000510 /* 000511 ** If expression pExpr is of type TK_SELECT, generate code to evaluate 000512 ** it. Return the register in which the result is stored (or, if the 000513 ** sub-select returns more than one column, the first in an array 000514 ** of registers in which the result is stored). 000515 ** 000516 ** If pExpr is not a TK_SELECT expression, return 0. 000517 */ 000518 static int exprCodeSubselect(Parse *pParse, Expr *pExpr){ 000519 int reg = 0; 000520 #ifndef SQLITE_OMIT_SUBQUERY 000521 if( pExpr->op==TK_SELECT ){ 000522 reg = sqlite3CodeSubselect(pParse, pExpr); 000523 } 000524 #endif 000525 return reg; 000526 } 000527 000528 /* 000529 ** Argument pVector points to a vector expression - either a TK_VECTOR 000530 ** or TK_SELECT that returns more than one column. This function returns 000531 ** the register number of a register that contains the value of 000532 ** element iField of the vector. 000533 ** 000534 ** If pVector is a TK_SELECT expression, then code for it must have 000535 ** already been generated using the exprCodeSubselect() routine. In this 000536 ** case parameter regSelect should be the first in an array of registers 000537 ** containing the results of the sub-select. 000538 ** 000539 ** If pVector is of type TK_VECTOR, then code for the requested field 000540 ** is generated. In this case (*pRegFree) may be set to the number of 000541 ** a temporary register to be freed by the caller before returning. 000542 ** 000543 ** Before returning, output parameter (*ppExpr) is set to point to the 000544 ** Expr object corresponding to element iElem of the vector. 000545 */ 000546 static int exprVectorRegister( 000547 Parse *pParse, /* Parse context */ 000548 Expr *pVector, /* Vector to extract element from */ 000549 int iField, /* Field to extract from pVector */ 000550 int regSelect, /* First in array of registers */ 000551 Expr **ppExpr, /* OUT: Expression element */ 000552 int *pRegFree /* OUT: Temp register to free */ 000553 ){ 000554 u8 op = pVector->op; 000555 assert( op==TK_VECTOR || op==TK_REGISTER || op==TK_SELECT ); 000556 if( op==TK_REGISTER ){ 000557 *ppExpr = sqlite3VectorFieldSubexpr(pVector, iField); 000558 return pVector->iTable+iField; 000559 } 000560 if( op==TK_SELECT ){ 000561 *ppExpr = pVector->x.pSelect->pEList->a[iField].pExpr; 000562 return regSelect+iField; 000563 } 000564 *ppExpr = pVector->x.pList->a[iField].pExpr; 000565 return sqlite3ExprCodeTemp(pParse, *ppExpr, pRegFree); 000566 } 000567 000568 /* 000569 ** Expression pExpr is a comparison between two vector values. Compute 000570 ** the result of the comparison (1, 0, or NULL) and write that 000571 ** result into register dest. 000572 ** 000573 ** The caller must satisfy the following preconditions: 000574 ** 000575 ** if pExpr->op==TK_IS: op==TK_EQ and p5==SQLITE_NULLEQ 000576 ** if pExpr->op==TK_ISNOT: op==TK_NE and p5==SQLITE_NULLEQ 000577 ** otherwise: op==pExpr->op and p5==0 000578 */ 000579 static void codeVectorCompare( 000580 Parse *pParse, /* Code generator context */ 000581 Expr *pExpr, /* The comparison operation */ 000582 int dest, /* Write results into this register */ 000583 u8 op, /* Comparison operator */ 000584 u8 p5 /* SQLITE_NULLEQ or zero */ 000585 ){ 000586 Vdbe *v = pParse->pVdbe; 000587 Expr *pLeft = pExpr->pLeft; 000588 Expr *pRight = pExpr->pRight; 000589 int nLeft = sqlite3ExprVectorSize(pLeft); 000590 int i; 000591 int regLeft = 0; 000592 int regRight = 0; 000593 u8 opx = op; 000594 int addrDone = sqlite3VdbeMakeLabel(pParse); 000595 int isCommuted = ExprHasProperty(pExpr,EP_Commuted); 000596 000597 if( pParse->nErr ) return; 000598 if( nLeft!=sqlite3ExprVectorSize(pRight) ){ 000599 sqlite3ErrorMsg(pParse, "row value misused"); 000600 return; 000601 } 000602 assert( pExpr->op==TK_EQ || pExpr->op==TK_NE 000603 || pExpr->op==TK_IS || pExpr->op==TK_ISNOT 000604 || pExpr->op==TK_LT || pExpr->op==TK_GT 000605 || pExpr->op==TK_LE || pExpr->op==TK_GE 000606 ); 000607 assert( pExpr->op==op || (pExpr->op==TK_IS && op==TK_EQ) 000608 || (pExpr->op==TK_ISNOT && op==TK_NE) ); 000609 assert( p5==0 || pExpr->op!=op ); 000610 assert( p5==SQLITE_NULLEQ || pExpr->op==op ); 000611 000612 p5 |= SQLITE_STOREP2; 000613 if( opx==TK_LE ) opx = TK_LT; 000614 if( opx==TK_GE ) opx = TK_GT; 000615 000616 regLeft = exprCodeSubselect(pParse, pLeft); 000617 regRight = exprCodeSubselect(pParse, pRight); 000618 000619 for(i=0; 1 /*Loop exits by "break"*/; i++){ 000620 int regFree1 = 0, regFree2 = 0; 000621 Expr *pL, *pR; 000622 int r1, r2; 000623 assert( i>=0 && i<nLeft ); 000624 r1 = exprVectorRegister(pParse, pLeft, i, regLeft, &pL, ®Free1); 000625 r2 = exprVectorRegister(pParse, pRight, i, regRight, &pR, ®Free2); 000626 codeCompare(pParse, pL, pR, opx, r1, r2, dest, p5, isCommuted); 000627 testcase(op==OP_Lt); VdbeCoverageIf(v,op==OP_Lt); 000628 testcase(op==OP_Le); VdbeCoverageIf(v,op==OP_Le); 000629 testcase(op==OP_Gt); VdbeCoverageIf(v,op==OP_Gt); 000630 testcase(op==OP_Ge); VdbeCoverageIf(v,op==OP_Ge); 000631 testcase(op==OP_Eq); VdbeCoverageIf(v,op==OP_Eq); 000632 testcase(op==OP_Ne); VdbeCoverageIf(v,op==OP_Ne); 000633 sqlite3ReleaseTempReg(pParse, regFree1); 000634 sqlite3ReleaseTempReg(pParse, regFree2); 000635 if( i==nLeft-1 ){ 000636 break; 000637 } 000638 if( opx==TK_EQ ){ 000639 sqlite3VdbeAddOp2(v, OP_IfNot, dest, addrDone); VdbeCoverage(v); 000640 p5 |= SQLITE_KEEPNULL; 000641 }else if( opx==TK_NE ){ 000642 sqlite3VdbeAddOp2(v, OP_If, dest, addrDone); VdbeCoverage(v); 000643 p5 |= SQLITE_KEEPNULL; 000644 }else{ 000645 assert( op==TK_LT || op==TK_GT || op==TK_LE || op==TK_GE ); 000646 sqlite3VdbeAddOp2(v, OP_ElseNotEq, 0, addrDone); 000647 VdbeCoverageIf(v, op==TK_LT); 000648 VdbeCoverageIf(v, op==TK_GT); 000649 VdbeCoverageIf(v, op==TK_LE); 000650 VdbeCoverageIf(v, op==TK_GE); 000651 if( i==nLeft-2 ) opx = op; 000652 } 000653 } 000654 sqlite3VdbeResolveLabel(v, addrDone); 000655 } 000656 000657 #if SQLITE_MAX_EXPR_DEPTH>0 000658 /* 000659 ** Check that argument nHeight is less than or equal to the maximum 000660 ** expression depth allowed. If it is not, leave an error message in 000661 ** pParse. 000662 */ 000663 int sqlite3ExprCheckHeight(Parse *pParse, int nHeight){ 000664 int rc = SQLITE_OK; 000665 int mxHeight = pParse->db->aLimit[SQLITE_LIMIT_EXPR_DEPTH]; 000666 if( nHeight>mxHeight ){ 000667 sqlite3ErrorMsg(pParse, 000668 "Expression tree is too large (maximum depth %d)", mxHeight 000669 ); 000670 rc = SQLITE_ERROR; 000671 } 000672 return rc; 000673 } 000674 000675 /* The following three functions, heightOfExpr(), heightOfExprList() 000676 ** and heightOfSelect(), are used to determine the maximum height 000677 ** of any expression tree referenced by the structure passed as the 000678 ** first argument. 000679 ** 000680 ** If this maximum height is greater than the current value pointed 000681 ** to by pnHeight, the second parameter, then set *pnHeight to that 000682 ** value. 000683 */ 000684 static void heightOfExpr(Expr *p, int *pnHeight){ 000685 if( p ){ 000686 if( p->nHeight>*pnHeight ){ 000687 *pnHeight = p->nHeight; 000688 } 000689 } 000690 } 000691 static void heightOfExprList(ExprList *p, int *pnHeight){ 000692 if( p ){ 000693 int i; 000694 for(i=0; i<p->nExpr; i++){ 000695 heightOfExpr(p->a[i].pExpr, pnHeight); 000696 } 000697 } 000698 } 000699 static void heightOfSelect(Select *pSelect, int *pnHeight){ 000700 Select *p; 000701 for(p=pSelect; p; p=p->pPrior){ 000702 heightOfExpr(p->pWhere, pnHeight); 000703 heightOfExpr(p->pHaving, pnHeight); 000704 heightOfExpr(p->pLimit, pnHeight); 000705 heightOfExprList(p->pEList, pnHeight); 000706 heightOfExprList(p->pGroupBy, pnHeight); 000707 heightOfExprList(p->pOrderBy, pnHeight); 000708 } 000709 } 000710 000711 /* 000712 ** Set the Expr.nHeight variable in the structure passed as an 000713 ** argument. An expression with no children, Expr.pList or 000714 ** Expr.pSelect member has a height of 1. Any other expression 000715 ** has a height equal to the maximum height of any other 000716 ** referenced Expr plus one. 000717 ** 000718 ** Also propagate EP_Propagate flags up from Expr.x.pList to Expr.flags, 000719 ** if appropriate. 000720 */ 000721 static void exprSetHeight(Expr *p){ 000722 int nHeight = 0; 000723 heightOfExpr(p->pLeft, &nHeight); 000724 heightOfExpr(p->pRight, &nHeight); 000725 if( ExprHasProperty(p, EP_xIsSelect) ){ 000726 heightOfSelect(p->x.pSelect, &nHeight); 000727 }else if( p->x.pList ){ 000728 heightOfExprList(p->x.pList, &nHeight); 000729 p->flags |= EP_Propagate & sqlite3ExprListFlags(p->x.pList); 000730 } 000731 p->nHeight = nHeight + 1; 000732 } 000733 000734 /* 000735 ** Set the Expr.nHeight variable using the exprSetHeight() function. If 000736 ** the height is greater than the maximum allowed expression depth, 000737 ** leave an error in pParse. 000738 ** 000739 ** Also propagate all EP_Propagate flags from the Expr.x.pList into 000740 ** Expr.flags. 000741 */ 000742 void sqlite3ExprSetHeightAndFlags(Parse *pParse, Expr *p){ 000743 if( pParse->nErr ) return; 000744 exprSetHeight(p); 000745 sqlite3ExprCheckHeight(pParse, p->nHeight); 000746 } 000747 000748 /* 000749 ** Return the maximum height of any expression tree referenced 000750 ** by the select statement passed as an argument. 000751 */ 000752 int sqlite3SelectExprHeight(Select *p){ 000753 int nHeight = 0; 000754 heightOfSelect(p, &nHeight); 000755 return nHeight; 000756 } 000757 #else /* ABOVE: Height enforcement enabled. BELOW: Height enforcement off */ 000758 /* 000759 ** Propagate all EP_Propagate flags from the Expr.x.pList into 000760 ** Expr.flags. 000761 */ 000762 void sqlite3ExprSetHeightAndFlags(Parse *pParse, Expr *p){ 000763 if( p && p->x.pList && !ExprHasProperty(p, EP_xIsSelect) ){ 000764 p->flags |= EP_Propagate & sqlite3ExprListFlags(p->x.pList); 000765 } 000766 } 000767 #define exprSetHeight(y) 000768 #endif /* SQLITE_MAX_EXPR_DEPTH>0 */ 000769 000770 /* 000771 ** This routine is the core allocator for Expr nodes. 000772 ** 000773 ** Construct a new expression node and return a pointer to it. Memory 000774 ** for this node and for the pToken argument is a single allocation 000775 ** obtained from sqlite3DbMalloc(). The calling function 000776 ** is responsible for making sure the node eventually gets freed. 000777 ** 000778 ** If dequote is true, then the token (if it exists) is dequoted. 000779 ** If dequote is false, no dequoting is performed. The deQuote 000780 ** parameter is ignored if pToken is NULL or if the token does not 000781 ** appear to be quoted. If the quotes were of the form "..." (double-quotes) 000782 ** then the EP_DblQuoted flag is set on the expression node. 000783 ** 000784 ** Special case: If op==TK_INTEGER and pToken points to a string that 000785 ** can be translated into a 32-bit integer, then the token is not 000786 ** stored in u.zToken. Instead, the integer values is written 000787 ** into u.iValue and the EP_IntValue flag is set. No extra storage 000788 ** is allocated to hold the integer text and the dequote flag is ignored. 000789 */ 000790 Expr *sqlite3ExprAlloc( 000791 sqlite3 *db, /* Handle for sqlite3DbMallocRawNN() */ 000792 int op, /* Expression opcode */ 000793 const Token *pToken, /* Token argument. Might be NULL */ 000794 int dequote /* True to dequote */ 000795 ){ 000796 Expr *pNew; 000797 int nExtra = 0; 000798 int iValue = 0; 000799 000800 assert( db!=0 ); 000801 if( pToken ){ 000802 if( op!=TK_INTEGER || pToken->z==0 000803 || sqlite3GetInt32(pToken->z, &iValue)==0 ){ 000804 nExtra = pToken->n+1; 000805 assert( iValue>=0 ); 000806 } 000807 } 000808 pNew = sqlite3DbMallocRawNN(db, sizeof(Expr)+nExtra); 000809 if( pNew ){ 000810 memset(pNew, 0, sizeof(Expr)); 000811 pNew->op = (u8)op; 000812 pNew->iAgg = -1; 000813 if( pToken ){ 000814 if( nExtra==0 ){ 000815 pNew->flags |= EP_IntValue|EP_Leaf|(iValue?EP_IsTrue:EP_IsFalse); 000816 pNew->u.iValue = iValue; 000817 }else{ 000818 pNew->u.zToken = (char*)&pNew[1]; 000819 assert( pToken->z!=0 || pToken->n==0 ); 000820 if( pToken->n ) memcpy(pNew->u.zToken, pToken->z, pToken->n); 000821 pNew->u.zToken[pToken->n] = 0; 000822 if( dequote && sqlite3Isquote(pNew->u.zToken[0]) ){ 000823 sqlite3DequoteExpr(pNew); 000824 } 000825 } 000826 } 000827 #if SQLITE_MAX_EXPR_DEPTH>0 000828 pNew->nHeight = 1; 000829 #endif 000830 } 000831 return pNew; 000832 } 000833 000834 /* 000835 ** Allocate a new expression node from a zero-terminated token that has 000836 ** already been dequoted. 000837 */ 000838 Expr *sqlite3Expr( 000839 sqlite3 *db, /* Handle for sqlite3DbMallocZero() (may be null) */ 000840 int op, /* Expression opcode */ 000841 const char *zToken /* Token argument. Might be NULL */ 000842 ){ 000843 Token x; 000844 x.z = zToken; 000845 x.n = sqlite3Strlen30(zToken); 000846 return sqlite3ExprAlloc(db, op, &x, 0); 000847 } 000848 000849 /* 000850 ** Attach subtrees pLeft and pRight to the Expr node pRoot. 000851 ** 000852 ** If pRoot==NULL that means that a memory allocation error has occurred. 000853 ** In that case, delete the subtrees pLeft and pRight. 000854 */ 000855 void sqlite3ExprAttachSubtrees( 000856 sqlite3 *db, 000857 Expr *pRoot, 000858 Expr *pLeft, 000859 Expr *pRight 000860 ){ 000861 if( pRoot==0 ){ 000862 assert( db->mallocFailed ); 000863 sqlite3ExprDelete(db, pLeft); 000864 sqlite3ExprDelete(db, pRight); 000865 }else{ 000866 if( pRight ){ 000867 pRoot->pRight = pRight; 000868 pRoot->flags |= EP_Propagate & pRight->flags; 000869 } 000870 if( pLeft ){ 000871 pRoot->pLeft = pLeft; 000872 pRoot->flags |= EP_Propagate & pLeft->flags; 000873 } 000874 exprSetHeight(pRoot); 000875 } 000876 } 000877 000878 /* 000879 ** Allocate an Expr node which joins as many as two subtrees. 000880 ** 000881 ** One or both of the subtrees can be NULL. Return a pointer to the new 000882 ** Expr node. Or, if an OOM error occurs, set pParse->db->mallocFailed, 000883 ** free the subtrees and return NULL. 000884 */ 000885 Expr *sqlite3PExpr( 000886 Parse *pParse, /* Parsing context */ 000887 int op, /* Expression opcode */ 000888 Expr *pLeft, /* Left operand */ 000889 Expr *pRight /* Right operand */ 000890 ){ 000891 Expr *p; 000892 p = sqlite3DbMallocRawNN(pParse->db, sizeof(Expr)); 000893 if( p ){ 000894 memset(p, 0, sizeof(Expr)); 000895 p->op = op & 0xff; 000896 p->iAgg = -1; 000897 sqlite3ExprAttachSubtrees(pParse->db, p, pLeft, pRight); 000898 sqlite3ExprCheckHeight(pParse, p->nHeight); 000899 }else{ 000900 sqlite3ExprDelete(pParse->db, pLeft); 000901 sqlite3ExprDelete(pParse->db, pRight); 000902 } 000903 return p; 000904 } 000905 000906 /* 000907 ** Add pSelect to the Expr.x.pSelect field. Or, if pExpr is NULL (due 000908 ** do a memory allocation failure) then delete the pSelect object. 000909 */ 000910 void sqlite3PExprAddSelect(Parse *pParse, Expr *pExpr, Select *pSelect){ 000911 if( pExpr ){ 000912 pExpr->x.pSelect = pSelect; 000913 ExprSetProperty(pExpr, EP_xIsSelect|EP_Subquery); 000914 sqlite3ExprSetHeightAndFlags(pParse, pExpr); 000915 }else{ 000916 assert( pParse->db->mallocFailed ); 000917 sqlite3SelectDelete(pParse->db, pSelect); 000918 } 000919 } 000920 000921 000922 /* 000923 ** Join two expressions using an AND operator. If either expression is 000924 ** NULL, then just return the other expression. 000925 ** 000926 ** If one side or the other of the AND is known to be false, then instead 000927 ** of returning an AND expression, just return a constant expression with 000928 ** a value of false. 000929 */ 000930 Expr *sqlite3ExprAnd(Parse *pParse, Expr *pLeft, Expr *pRight){ 000931 sqlite3 *db = pParse->db; 000932 if( pLeft==0 ){ 000933 return pRight; 000934 }else if( pRight==0 ){ 000935 return pLeft; 000936 }else if( ExprAlwaysFalse(pLeft) || ExprAlwaysFalse(pRight) ){ 000937 sqlite3ExprUnmapAndDelete(pParse, pLeft); 000938 sqlite3ExprUnmapAndDelete(pParse, pRight); 000939 return sqlite3Expr(db, TK_INTEGER, "0"); 000940 }else{ 000941 return sqlite3PExpr(pParse, TK_AND, pLeft, pRight); 000942 } 000943 } 000944 000945 /* 000946 ** Construct a new expression node for a function with multiple 000947 ** arguments. 000948 */ 000949 Expr *sqlite3ExprFunction( 000950 Parse *pParse, /* Parsing context */ 000951 ExprList *pList, /* Argument list */ 000952 Token *pToken, /* Name of the function */ 000953 int eDistinct /* SF_Distinct or SF_ALL or 0 */ 000954 ){ 000955 Expr *pNew; 000956 sqlite3 *db = pParse->db; 000957 assert( pToken ); 000958 pNew = sqlite3ExprAlloc(db, TK_FUNCTION, pToken, 1); 000959 if( pNew==0 ){ 000960 sqlite3ExprListDelete(db, pList); /* Avoid memory leak when malloc fails */ 000961 return 0; 000962 } 000963 if( pList && pList->nExpr > pParse->db->aLimit[SQLITE_LIMIT_FUNCTION_ARG] ){ 000964 sqlite3ErrorMsg(pParse, "too many arguments on function %T", pToken); 000965 } 000966 pNew->x.pList = pList; 000967 ExprSetProperty(pNew, EP_HasFunc); 000968 assert( !ExprHasProperty(pNew, EP_xIsSelect) ); 000969 sqlite3ExprSetHeightAndFlags(pParse, pNew); 000970 if( eDistinct==SF_Distinct ) ExprSetProperty(pNew, EP_Distinct); 000971 return pNew; 000972 } 000973 000974 /* 000975 ** Assign a variable number to an expression that encodes a wildcard 000976 ** in the original SQL statement. 000977 ** 000978 ** Wildcards consisting of a single "?" are assigned the next sequential 000979 ** variable number. 000980 ** 000981 ** Wildcards of the form "?nnn" are assigned the number "nnn". We make 000982 ** sure "nnn" is not too big to avoid a denial of service attack when 000983 ** the SQL statement comes from an external source. 000984 ** 000985 ** Wildcards of the form ":aaa", "@aaa", or "$aaa" are assigned the same number 000986 ** as the previous instance of the same wildcard. Or if this is the first 000987 ** instance of the wildcard, the next sequential variable number is 000988 ** assigned. 000989 */ 000990 void sqlite3ExprAssignVarNumber(Parse *pParse, Expr *pExpr, u32 n){ 000991 sqlite3 *db = pParse->db; 000992 const char *z; 000993 ynVar x; 000994 000995 if( pExpr==0 ) return; 000996 assert( !ExprHasProperty(pExpr, EP_IntValue|EP_Reduced|EP_TokenOnly) ); 000997 z = pExpr->u.zToken; 000998 assert( z!=0 ); 000999 assert( z[0]!=0 ); 001000 assert( n==(u32)sqlite3Strlen30(z) ); 001001 if( z[1]==0 ){ 001002 /* Wildcard of the form "?". Assign the next variable number */ 001003 assert( z[0]=='?' ); 001004 x = (ynVar)(++pParse->nVar); 001005 }else{ 001006 int doAdd = 0; 001007 if( z[0]=='?' ){ 001008 /* Wildcard of the form "?nnn". Convert "nnn" to an integer and 001009 ** use it as the variable number */ 001010 i64 i; 001011 int bOk; 001012 if( n==2 ){ /*OPTIMIZATION-IF-TRUE*/ 001013 i = z[1]-'0'; /* The common case of ?N for a single digit N */ 001014 bOk = 1; 001015 }else{ 001016 bOk = 0==sqlite3Atoi64(&z[1], &i, n-1, SQLITE_UTF8); 001017 } 001018 testcase( i==0 ); 001019 testcase( i==1 ); 001020 testcase( i==db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER]-1 ); 001021 testcase( i==db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] ); 001022 if( bOk==0 || i<1 || i>db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] ){ 001023 sqlite3ErrorMsg(pParse, "variable number must be between ?1 and ?%d", 001024 db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER]); 001025 return; 001026 } 001027 x = (ynVar)i; 001028 if( x>pParse->nVar ){ 001029 pParse->nVar = (int)x; 001030 doAdd = 1; 001031 }else if( sqlite3VListNumToName(pParse->pVList, x)==0 ){ 001032 doAdd = 1; 001033 } 001034 }else{ 001035 /* Wildcards like ":aaa", "$aaa" or "@aaa". Reuse the same variable 001036 ** number as the prior appearance of the same name, or if the name 001037 ** has never appeared before, reuse the same variable number 001038 */ 001039 x = (ynVar)sqlite3VListNameToNum(pParse->pVList, z, n); 001040 if( x==0 ){ 001041 x = (ynVar)(++pParse->nVar); 001042 doAdd = 1; 001043 } 001044 } 001045 if( doAdd ){ 001046 pParse->pVList = sqlite3VListAdd(db, pParse->pVList, z, n, x); 001047 } 001048 } 001049 pExpr->iColumn = x; 001050 if( x>db->aLimit[SQLITE_LIMIT_VARIABLE_NUMBER] ){ 001051 sqlite3ErrorMsg(pParse, "too many SQL variables"); 001052 } 001053 } 001054 001055 /* 001056 ** Recursively delete an expression tree. 001057 */ 001058 static SQLITE_NOINLINE void sqlite3ExprDeleteNN(sqlite3 *db, Expr *p){ 001059 assert( p!=0 ); 001060 /* Sanity check: Assert that the IntValue is non-negative if it exists */ 001061 assert( !ExprHasProperty(p, EP_IntValue) || p->u.iValue>=0 ); 001062 001063 assert( !ExprHasProperty(p, EP_WinFunc) || p->y.pWin!=0 || db->mallocFailed ); 001064 assert( p->op!=TK_FUNCTION || ExprHasProperty(p, EP_TokenOnly|EP_Reduced) 001065 || p->y.pWin==0 || ExprHasProperty(p, EP_WinFunc) ); 001066 #ifdef SQLITE_DEBUG 001067 if( ExprHasProperty(p, EP_Leaf) && !ExprHasProperty(p, EP_TokenOnly) ){ 001068 assert( p->pLeft==0 ); 001069 assert( p->pRight==0 ); 001070 assert( p->x.pSelect==0 ); 001071 } 001072 #endif 001073 if( !ExprHasProperty(p, (EP_TokenOnly|EP_Leaf)) ){ 001074 /* The Expr.x union is never used at the same time as Expr.pRight */ 001075 assert( p->x.pList==0 || p->pRight==0 ); 001076 if( p->pLeft && p->op!=TK_SELECT_COLUMN ) sqlite3ExprDeleteNN(db, p->pLeft); 001077 if( p->pRight ){ 001078 assert( !ExprHasProperty(p, EP_WinFunc) ); 001079 sqlite3ExprDeleteNN(db, p->pRight); 001080 }else if( ExprHasProperty(p, EP_xIsSelect) ){ 001081 assert( !ExprHasProperty(p, EP_WinFunc) ); 001082 sqlite3SelectDelete(db, p->x.pSelect); 001083 }else{ 001084 sqlite3ExprListDelete(db, p->x.pList); 001085 #ifndef SQLITE_OMIT_WINDOWFUNC 001086 if( ExprHasProperty(p, EP_WinFunc) ){ 001087 sqlite3WindowDelete(db, p->y.pWin); 001088 } 001089 #endif 001090 } 001091 } 001092 if( ExprHasProperty(p, EP_MemToken) ) sqlite3DbFree(db, p->u.zToken); 001093 if( !ExprHasProperty(p, EP_Static) ){ 001094 sqlite3DbFreeNN(db, p); 001095 } 001096 } 001097 void sqlite3ExprDelete(sqlite3 *db, Expr *p){ 001098 if( p ) sqlite3ExprDeleteNN(db, p); 001099 } 001100 001101 /* Invoke sqlite3RenameExprUnmap() and sqlite3ExprDelete() on the 001102 ** expression. 001103 */ 001104 void sqlite3ExprUnmapAndDelete(Parse *pParse, Expr *p){ 001105 if( p ){ 001106 if( IN_RENAME_OBJECT ){ 001107 sqlite3RenameExprUnmap(pParse, p); 001108 } 001109 sqlite3ExprDeleteNN(pParse->db, p); 001110 } 001111 } 001112 001113 /* 001114 ** Return the number of bytes allocated for the expression structure 001115 ** passed as the first argument. This is always one of EXPR_FULLSIZE, 001116 ** EXPR_REDUCEDSIZE or EXPR_TOKENONLYSIZE. 001117 */ 001118 static int exprStructSize(Expr *p){ 001119 if( ExprHasProperty(p, EP_TokenOnly) ) return EXPR_TOKENONLYSIZE; 001120 if( ExprHasProperty(p, EP_Reduced) ) return EXPR_REDUCEDSIZE; 001121 return EXPR_FULLSIZE; 001122 } 001123 001124 /* 001125 ** The dupedExpr*Size() routines each return the number of bytes required 001126 ** to store a copy of an expression or expression tree. They differ in 001127 ** how much of the tree is measured. 001128 ** 001129 ** dupedExprStructSize() Size of only the Expr structure 001130 ** dupedExprNodeSize() Size of Expr + space for token 001131 ** dupedExprSize() Expr + token + subtree components 001132 ** 001133 *************************************************************************** 001134 ** 001135 ** The dupedExprStructSize() function returns two values OR-ed together: 001136 ** (1) the space required for a copy of the Expr structure only and 001137 ** (2) the EP_xxx flags that indicate what the structure size should be. 001138 ** The return values is always one of: 001139 ** 001140 ** EXPR_FULLSIZE 001141 ** EXPR_REDUCEDSIZE | EP_Reduced 001142 ** EXPR_TOKENONLYSIZE | EP_TokenOnly 001143 ** 001144 ** The size of the structure can be found by masking the return value 001145 ** of this routine with 0xfff. The flags can be found by masking the 001146 ** return value with EP_Reduced|EP_TokenOnly. 001147 ** 001148 ** Note that with flags==EXPRDUP_REDUCE, this routines works on full-size 001149 ** (unreduced) Expr objects as they or originally constructed by the parser. 001150 ** During expression analysis, extra information is computed and moved into 001151 ** later parts of the Expr object and that extra information might get chopped 001152 ** off if the expression is reduced. Note also that it does not work to 001153 ** make an EXPRDUP_REDUCE copy of a reduced expression. It is only legal 001154 ** to reduce a pristine expression tree from the parser. The implementation 001155 ** of dupedExprStructSize() contain multiple assert() statements that attempt 001156 ** to enforce this constraint. 001157 */ 001158 static int dupedExprStructSize(Expr *p, int flags){ 001159 int nSize; 001160 assert( flags==EXPRDUP_REDUCE || flags==0 ); /* Only one flag value allowed */ 001161 assert( EXPR_FULLSIZE<=0xfff ); 001162 assert( (0xfff & (EP_Reduced|EP_TokenOnly))==0 ); 001163 if( 0==flags || p->op==TK_SELECT_COLUMN 001164 #ifndef SQLITE_OMIT_WINDOWFUNC 001165 || ExprHasProperty(p, EP_WinFunc) 001166 #endif 001167 ){ 001168 nSize = EXPR_FULLSIZE; 001169 }else{ 001170 assert( !ExprHasProperty(p, EP_TokenOnly|EP_Reduced) ); 001171 assert( !ExprHasProperty(p, EP_FromJoin) ); 001172 assert( !ExprHasProperty(p, EP_MemToken) ); 001173 assert( !ExprHasProperty(p, EP_NoReduce) ); 001174 if( p->pLeft || p->x.pList ){ 001175 nSize = EXPR_REDUCEDSIZE | EP_Reduced; 001176 }else{ 001177 assert( p->pRight==0 ); 001178 nSize = EXPR_TOKENONLYSIZE | EP_TokenOnly; 001179 } 001180 } 001181 return nSize; 001182 } 001183 001184 /* 001185 ** This function returns the space in bytes required to store the copy 001186 ** of the Expr structure and a copy of the Expr.u.zToken string (if that 001187 ** string is defined.) 001188 */ 001189 static int dupedExprNodeSize(Expr *p, int flags){ 001190 int nByte = dupedExprStructSize(p, flags) & 0xfff; 001191 if( !ExprHasProperty(p, EP_IntValue) && p->u.zToken ){ 001192 nByte += sqlite3Strlen30NN(p->u.zToken)+1; 001193 } 001194 return ROUND8(nByte); 001195 } 001196 001197 /* 001198 ** Return the number of bytes required to create a duplicate of the 001199 ** expression passed as the first argument. The second argument is a 001200 ** mask containing EXPRDUP_XXX flags. 001201 ** 001202 ** The value returned includes space to create a copy of the Expr struct 001203 ** itself and the buffer referred to by Expr.u.zToken, if any. 001204 ** 001205 ** If the EXPRDUP_REDUCE flag is set, then the return value includes 001206 ** space to duplicate all Expr nodes in the tree formed by Expr.pLeft 001207 ** and Expr.pRight variables (but not for any structures pointed to or 001208 ** descended from the Expr.x.pList or Expr.x.pSelect variables). 001209 */ 001210 static int dupedExprSize(Expr *p, int flags){ 001211 int nByte = 0; 001212 if( p ){ 001213 nByte = dupedExprNodeSize(p, flags); 001214 if( flags&EXPRDUP_REDUCE ){ 001215 nByte += dupedExprSize(p->pLeft, flags) + dupedExprSize(p->pRight, flags); 001216 } 001217 } 001218 return nByte; 001219 } 001220 001221 /* 001222 ** This function is similar to sqlite3ExprDup(), except that if pzBuffer 001223 ** is not NULL then *pzBuffer is assumed to point to a buffer large enough 001224 ** to store the copy of expression p, the copies of p->u.zToken 001225 ** (if applicable), and the copies of the p->pLeft and p->pRight expressions, 001226 ** if any. Before returning, *pzBuffer is set to the first byte past the 001227 ** portion of the buffer copied into by this function. 001228 */ 001229 static Expr *exprDup(sqlite3 *db, Expr *p, int dupFlags, u8 **pzBuffer){ 001230 Expr *pNew; /* Value to return */ 001231 u8 *zAlloc; /* Memory space from which to build Expr object */ 001232 u32 staticFlag; /* EP_Static if space not obtained from malloc */ 001233 001234 assert( db!=0 ); 001235 assert( p ); 001236 assert( dupFlags==0 || dupFlags==EXPRDUP_REDUCE ); 001237 assert( pzBuffer==0 || dupFlags==EXPRDUP_REDUCE ); 001238 001239 /* Figure out where to write the new Expr structure. */ 001240 if( pzBuffer ){ 001241 zAlloc = *pzBuffer; 001242 staticFlag = EP_Static; 001243 }else{ 001244 zAlloc = sqlite3DbMallocRawNN(db, dupedExprSize(p, dupFlags)); 001245 staticFlag = 0; 001246 } 001247 pNew = (Expr *)zAlloc; 001248 001249 if( pNew ){ 001250 /* Set nNewSize to the size allocated for the structure pointed to 001251 ** by pNew. This is either EXPR_FULLSIZE, EXPR_REDUCEDSIZE or 001252 ** EXPR_TOKENONLYSIZE. nToken is set to the number of bytes consumed 001253 ** by the copy of the p->u.zToken string (if any). 001254 */ 001255 const unsigned nStructSize = dupedExprStructSize(p, dupFlags); 001256 const int nNewSize = nStructSize & 0xfff; 001257 int nToken; 001258 if( !ExprHasProperty(p, EP_IntValue) && p->u.zToken ){ 001259 nToken = sqlite3Strlen30(p->u.zToken) + 1; 001260 }else{ 001261 nToken = 0; 001262 } 001263 if( dupFlags ){ 001264 assert( ExprHasProperty(p, EP_Reduced)==0 ); 001265 memcpy(zAlloc, p, nNewSize); 001266 }else{ 001267 u32 nSize = (u32)exprStructSize(p); 001268 memcpy(zAlloc, p, nSize); 001269 if( nSize<EXPR_FULLSIZE ){ 001270 memset(&zAlloc[nSize], 0, EXPR_FULLSIZE-nSize); 001271 } 001272 } 001273 001274 /* Set the EP_Reduced, EP_TokenOnly, and EP_Static flags appropriately. */ 001275 pNew->flags &= ~(EP_Reduced|EP_TokenOnly|EP_Static|EP_MemToken); 001276 pNew->flags |= nStructSize & (EP_Reduced|EP_TokenOnly); 001277 pNew->flags |= staticFlag; 001278 001279 /* Copy the p->u.zToken string, if any. */ 001280 if( nToken ){ 001281 char *zToken = pNew->u.zToken = (char*)&zAlloc[nNewSize]; 001282 memcpy(zToken, p->u.zToken, nToken); 001283 } 001284 001285 if( 0==((p->flags|pNew->flags) & (EP_TokenOnly|EP_Leaf)) ){ 001286 /* Fill in the pNew->x.pSelect or pNew->x.pList member. */ 001287 if( ExprHasProperty(p, EP_xIsSelect) ){ 001288 pNew->x.pSelect = sqlite3SelectDup(db, p->x.pSelect, dupFlags); 001289 }else{ 001290 pNew->x.pList = sqlite3ExprListDup(db, p->x.pList, dupFlags); 001291 } 001292 } 001293 001294 /* Fill in pNew->pLeft and pNew->pRight. */ 001295 if( ExprHasProperty(pNew, EP_Reduced|EP_TokenOnly|EP_WinFunc) ){ 001296 zAlloc += dupedExprNodeSize(p, dupFlags); 001297 if( !ExprHasProperty(pNew, EP_TokenOnly|EP_Leaf) ){ 001298 pNew->pLeft = p->pLeft ? 001299 exprDup(db, p->pLeft, EXPRDUP_REDUCE, &zAlloc) : 0; 001300 pNew->pRight = p->pRight ? 001301 exprDup(db, p->pRight, EXPRDUP_REDUCE, &zAlloc) : 0; 001302 } 001303 #ifndef SQLITE_OMIT_WINDOWFUNC 001304 if( ExprHasProperty(p, EP_WinFunc) ){ 001305 pNew->y.pWin = sqlite3WindowDup(db, pNew, p->y.pWin); 001306 assert( ExprHasProperty(pNew, EP_WinFunc) ); 001307 } 001308 #endif /* SQLITE_OMIT_WINDOWFUNC */ 001309 if( pzBuffer ){ 001310 *pzBuffer = zAlloc; 001311 } 001312 }else{ 001313 if( !ExprHasProperty(p, EP_TokenOnly|EP_Leaf) ){ 001314 if( pNew->op==TK_SELECT_COLUMN ){ 001315 pNew->pLeft = p->pLeft; 001316 assert( p->iColumn==0 || p->pRight==0 ); 001317 assert( p->pRight==0 || p->pRight==p->pLeft ); 001318 }else{ 001319 pNew->pLeft = sqlite3ExprDup(db, p->pLeft, 0); 001320 } 001321 pNew->pRight = sqlite3ExprDup(db, p->pRight, 0); 001322 } 001323 } 001324 } 001325 return pNew; 001326 } 001327 001328 /* 001329 ** Create and return a deep copy of the object passed as the second 001330 ** argument. If an OOM condition is encountered, NULL is returned 001331 ** and the db->mallocFailed flag set. 001332 */ 001333 #ifndef SQLITE_OMIT_CTE 001334 static With *withDup(sqlite3 *db, With *p){ 001335 With *pRet = 0; 001336 if( p ){ 001337 sqlite3_int64 nByte = sizeof(*p) + sizeof(p->a[0]) * (p->nCte-1); 001338 pRet = sqlite3DbMallocZero(db, nByte); 001339 if( pRet ){ 001340 int i; 001341 pRet->nCte = p->nCte; 001342 for(i=0; i<p->nCte; i++){ 001343 pRet->a[i].pSelect = sqlite3SelectDup(db, p->a[i].pSelect, 0); 001344 pRet->a[i].pCols = sqlite3ExprListDup(db, p->a[i].pCols, 0); 001345 pRet->a[i].zName = sqlite3DbStrDup(db, p->a[i].zName); 001346 } 001347 } 001348 } 001349 return pRet; 001350 } 001351 #else 001352 # define withDup(x,y) 0 001353 #endif 001354 001355 #ifndef SQLITE_OMIT_WINDOWFUNC 001356 /* 001357 ** The gatherSelectWindows() procedure and its helper routine 001358 ** gatherSelectWindowsCallback() are used to scan all the expressions 001359 ** an a newly duplicated SELECT statement and gather all of the Window 001360 ** objects found there, assembling them onto the linked list at Select->pWin. 001361 */ 001362 static int gatherSelectWindowsCallback(Walker *pWalker, Expr *pExpr){ 001363 if( pExpr->op==TK_FUNCTION && ExprHasProperty(pExpr, EP_WinFunc) ){ 001364 Select *pSelect = pWalker->u.pSelect; 001365 Window *pWin = pExpr->y.pWin; 001366 assert( pWin ); 001367 assert( IsWindowFunc(pExpr) ); 001368 assert( pWin->ppThis==0 ); 001369 sqlite3WindowLink(pSelect, pWin); 001370 } 001371 return WRC_Continue; 001372 } 001373 static int gatherSelectWindowsSelectCallback(Walker *pWalker, Select *p){ 001374 return p==pWalker->u.pSelect ? WRC_Continue : WRC_Prune; 001375 } 001376 static void gatherSelectWindows(Select *p){ 001377 Walker w; 001378 w.xExprCallback = gatherSelectWindowsCallback; 001379 w.xSelectCallback = gatherSelectWindowsSelectCallback; 001380 w.xSelectCallback2 = 0; 001381 w.pParse = 0; 001382 w.u.pSelect = p; 001383 sqlite3WalkSelect(&w, p); 001384 } 001385 #endif 001386 001387 001388 /* 001389 ** The following group of routines make deep copies of expressions, 001390 ** expression lists, ID lists, and select statements. The copies can 001391 ** be deleted (by being passed to their respective ...Delete() routines) 001392 ** without effecting the originals. 001393 ** 001394 ** The expression list, ID, and source lists return by sqlite3ExprListDup(), 001395 ** sqlite3IdListDup(), and sqlite3SrcListDup() can not be further expanded 001396 ** by subsequent calls to sqlite*ListAppend() routines. 001397 ** 001398 ** Any tables that the SrcList might point to are not duplicated. 001399 ** 001400 ** The flags parameter contains a combination of the EXPRDUP_XXX flags. 001401 ** If the EXPRDUP_REDUCE flag is set, then the structure returned is a 001402 ** truncated version of the usual Expr structure that will be stored as 001403 ** part of the in-memory representation of the database schema. 001404 */ 001405 Expr *sqlite3ExprDup(sqlite3 *db, Expr *p, int flags){ 001406 assert( flags==0 || flags==EXPRDUP_REDUCE ); 001407 return p ? exprDup(db, p, flags, 0) : 0; 001408 } 001409 ExprList *sqlite3ExprListDup(sqlite3 *db, ExprList *p, int flags){ 001410 ExprList *pNew; 001411 struct ExprList_item *pItem, *pOldItem; 001412 int i; 001413 Expr *pPriorSelectCol = 0; 001414 assert( db!=0 ); 001415 if( p==0 ) return 0; 001416 pNew = sqlite3DbMallocRawNN(db, sqlite3DbMallocSize(db, p)); 001417 if( pNew==0 ) return 0; 001418 pNew->nExpr = p->nExpr; 001419 pItem = pNew->a; 001420 pOldItem = p->a; 001421 for(i=0; i<p->nExpr; i++, pItem++, pOldItem++){ 001422 Expr *pOldExpr = pOldItem->pExpr; 001423 Expr *pNewExpr; 001424 pItem->pExpr = sqlite3ExprDup(db, pOldExpr, flags); 001425 if( pOldExpr 001426 && pOldExpr->op==TK_SELECT_COLUMN 001427 && (pNewExpr = pItem->pExpr)!=0 001428 ){ 001429 assert( pNewExpr->iColumn==0 || i>0 ); 001430 if( pNewExpr->iColumn==0 ){ 001431 assert( pOldExpr->pLeft==pOldExpr->pRight ); 001432 pPriorSelectCol = pNewExpr->pLeft = pNewExpr->pRight; 001433 }else{ 001434 assert( i>0 ); 001435 assert( pItem[-1].pExpr!=0 ); 001436 assert( pNewExpr->iColumn==pItem[-1].pExpr->iColumn+1 ); 001437 assert( pPriorSelectCol==pItem[-1].pExpr->pLeft ); 001438 pNewExpr->pLeft = pPriorSelectCol; 001439 } 001440 } 001441 pItem->zName = sqlite3DbStrDup(db, pOldItem->zName); 001442 pItem->zSpan = sqlite3DbStrDup(db, pOldItem->zSpan); 001443 pItem->sortFlags = pOldItem->sortFlags; 001444 pItem->done = 0; 001445 pItem->bNulls = pOldItem->bNulls; 001446 pItem->bSpanIsTab = pOldItem->bSpanIsTab; 001447 pItem->bSorterRef = pOldItem->bSorterRef; 001448 pItem->u = pOldItem->u; 001449 } 001450 return pNew; 001451 } 001452 001453 /* 001454 ** If cursors, triggers, views and subqueries are all omitted from 001455 ** the build, then none of the following routines, except for 001456 ** sqlite3SelectDup(), can be called. sqlite3SelectDup() is sometimes 001457 ** called with a NULL argument. 001458 */ 001459 #if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_TRIGGER) \ 001460 || !defined(SQLITE_OMIT_SUBQUERY) 001461 SrcList *sqlite3SrcListDup(sqlite3 *db, SrcList *p, int flags){ 001462 SrcList *pNew; 001463 int i; 001464 int nByte; 001465 assert( db!=0 ); 001466 if( p==0 ) return 0; 001467 nByte = sizeof(*p) + (p->nSrc>0 ? sizeof(p->a[0]) * (p->nSrc-1) : 0); 001468 pNew = sqlite3DbMallocRawNN(db, nByte ); 001469 if( pNew==0 ) return 0; 001470 pNew->nSrc = pNew->nAlloc = p->nSrc; 001471 for(i=0; i<p->nSrc; i++){ 001472 struct SrcList_item *pNewItem = &pNew->a[i]; 001473 struct SrcList_item *pOldItem = &p->a[i]; 001474 Table *pTab; 001475 pNewItem->pSchema = pOldItem->pSchema; 001476 pNewItem->zDatabase = sqlite3DbStrDup(db, pOldItem->zDatabase); 001477 pNewItem->zName = sqlite3DbStrDup(db, pOldItem->zName); 001478 pNewItem->zAlias = sqlite3DbStrDup(db, pOldItem->zAlias); 001479 pNewItem->fg = pOldItem->fg; 001480 pNewItem->iCursor = pOldItem->iCursor; 001481 pNewItem->addrFillSub = pOldItem->addrFillSub; 001482 pNewItem->regReturn = pOldItem->regReturn; 001483 if( pNewItem->fg.isIndexedBy ){ 001484 pNewItem->u1.zIndexedBy = sqlite3DbStrDup(db, pOldItem->u1.zIndexedBy); 001485 } 001486 pNewItem->pIBIndex = pOldItem->pIBIndex; 001487 if( pNewItem->fg.isTabFunc ){ 001488 pNewItem->u1.pFuncArg = 001489 sqlite3ExprListDup(db, pOldItem->u1.pFuncArg, flags); 001490 } 001491 pTab = pNewItem->pTab = pOldItem->pTab; 001492 if( pTab ){ 001493 pTab->nTabRef++; 001494 } 001495 pNewItem->pSelect = sqlite3SelectDup(db, pOldItem->pSelect, flags); 001496 pNewItem->pOn = sqlite3ExprDup(db, pOldItem->pOn, flags); 001497 pNewItem->pUsing = sqlite3IdListDup(db, pOldItem->pUsing); 001498 pNewItem->colUsed = pOldItem->colUsed; 001499 } 001500 return pNew; 001501 } 001502 IdList *sqlite3IdListDup(sqlite3 *db, IdList *p){ 001503 IdList *pNew; 001504 int i; 001505 assert( db!=0 ); 001506 if( p==0 ) return 0; 001507 pNew = sqlite3DbMallocRawNN(db, sizeof(*pNew) ); 001508 if( pNew==0 ) return 0; 001509 pNew->nId = p->nId; 001510 pNew->a = sqlite3DbMallocRawNN(db, p->nId*sizeof(p->a[0]) ); 001511 if( pNew->a==0 ){ 001512 sqlite3DbFreeNN(db, pNew); 001513 return 0; 001514 } 001515 /* Note that because the size of the allocation for p->a[] is not 001516 ** necessarily a power of two, sqlite3IdListAppend() may not be called 001517 ** on the duplicate created by this function. */ 001518 for(i=0; i<p->nId; i++){ 001519 struct IdList_item *pNewItem = &pNew->a[i]; 001520 struct IdList_item *pOldItem = &p->a[i]; 001521 pNewItem->zName = sqlite3DbStrDup(db, pOldItem->zName); 001522 pNewItem->idx = pOldItem->idx; 001523 } 001524 return pNew; 001525 } 001526 Select *sqlite3SelectDup(sqlite3 *db, Select *pDup, int flags){ 001527 Select *pRet = 0; 001528 Select *pNext = 0; 001529 Select **pp = &pRet; 001530 Select *p; 001531 001532 assert( db!=0 ); 001533 for(p=pDup; p; p=p->pPrior){ 001534 Select *pNew = sqlite3DbMallocRawNN(db, sizeof(*p) ); 001535 if( pNew==0 ) break; 001536 pNew->pEList = sqlite3ExprListDup(db, p->pEList, flags); 001537 pNew->pSrc = sqlite3SrcListDup(db, p->pSrc, flags); 001538 pNew->pWhere = sqlite3ExprDup(db, p->pWhere, flags); 001539 pNew->pGroupBy = sqlite3ExprListDup(db, p->pGroupBy, flags); 001540 pNew->pHaving = sqlite3ExprDup(db, p->pHaving, flags); 001541 pNew->pOrderBy = sqlite3ExprListDup(db, p->pOrderBy, flags); 001542 pNew->op = p->op; 001543 pNew->pNext = pNext; 001544 pNew->pPrior = 0; 001545 pNew->pLimit = sqlite3ExprDup(db, p->pLimit, flags); 001546 pNew->iLimit = 0; 001547 pNew->iOffset = 0; 001548 pNew->selFlags = p->selFlags & ~SF_UsesEphemeral; 001549 pNew->addrOpenEphm[0] = -1; 001550 pNew->addrOpenEphm[1] = -1; 001551 pNew->nSelectRow = p->nSelectRow; 001552 pNew->pWith = withDup(db, p->pWith); 001553 #ifndef SQLITE_OMIT_WINDOWFUNC 001554 pNew->pWin = 0; 001555 pNew->pWinDefn = sqlite3WindowListDup(db, p->pWinDefn); 001556 if( p->pWin && db->mallocFailed==0 ) gatherSelectWindows(pNew); 001557 #endif 001558 pNew->selId = p->selId; 001559 *pp = pNew; 001560 pp = &pNew->pPrior; 001561 pNext = pNew; 001562 } 001563 001564 return pRet; 001565 } 001566 #else 001567 Select *sqlite3SelectDup(sqlite3 *db, Select *p, int flags){ 001568 assert( p==0 ); 001569 return 0; 001570 } 001571 #endif 001572 001573 001574 /* 001575 ** Add a new element to the end of an expression list. If pList is 001576 ** initially NULL, then create a new expression list. 001577 ** 001578 ** The pList argument must be either NULL or a pointer to an ExprList 001579 ** obtained from a prior call to sqlite3ExprListAppend(). This routine 001580 ** may not be used with an ExprList obtained from sqlite3ExprListDup(). 001581 ** Reason: This routine assumes that the number of slots in pList->a[] 001582 ** is a power of two. That is true for sqlite3ExprListAppend() returns 001583 ** but is not necessarily true from the return value of sqlite3ExprListDup(). 001584 ** 001585 ** If a memory allocation error occurs, the entire list is freed and 001586 ** NULL is returned. If non-NULL is returned, then it is guaranteed 001587 ** that the new entry was successfully appended. 001588 */ 001589 ExprList *sqlite3ExprListAppend( 001590 Parse *pParse, /* Parsing context */ 001591 ExprList *pList, /* List to which to append. Might be NULL */ 001592 Expr *pExpr /* Expression to be appended. Might be NULL */ 001593 ){ 001594 struct ExprList_item *pItem; 001595 sqlite3 *db = pParse->db; 001596 assert( db!=0 ); 001597 if( pList==0 ){ 001598 pList = sqlite3DbMallocRawNN(db, sizeof(ExprList) ); 001599 if( pList==0 ){ 001600 goto no_mem; 001601 } 001602 pList->nExpr = 0; 001603 }else if( (pList->nExpr & (pList->nExpr-1))==0 ){ 001604 ExprList *pNew; 001605 pNew = sqlite3DbRealloc(db, pList, 001606 sizeof(*pList)+(2*(sqlite3_int64)pList->nExpr-1)*sizeof(pList->a[0])); 001607 if( pNew==0 ){ 001608 goto no_mem; 001609 } 001610 pList = pNew; 001611 } 001612 pItem = &pList->a[pList->nExpr++]; 001613 assert( offsetof(struct ExprList_item,zName)==sizeof(pItem->pExpr) ); 001614 assert( offsetof(struct ExprList_item,pExpr)==0 ); 001615 memset(&pItem->zName,0,sizeof(*pItem)-offsetof(struct ExprList_item,zName)); 001616 pItem->pExpr = pExpr; 001617 return pList; 001618 001619 no_mem: 001620 /* Avoid leaking memory if malloc has failed. */ 001621 sqlite3ExprDelete(db, pExpr); 001622 sqlite3ExprListDelete(db, pList); 001623 return 0; 001624 } 001625 001626 /* 001627 ** pColumns and pExpr form a vector assignment which is part of the SET 001628 ** clause of an UPDATE statement. Like this: 001629 ** 001630 ** (a,b,c) = (expr1,expr2,expr3) 001631 ** Or: (a,b,c) = (SELECT x,y,z FROM ....) 001632 ** 001633 ** For each term of the vector assignment, append new entries to the 001634 ** expression list pList. In the case of a subquery on the RHS, append 001635 ** TK_SELECT_COLUMN expressions. 001636 */ 001637 ExprList *sqlite3ExprListAppendVector( 001638 Parse *pParse, /* Parsing context */ 001639 ExprList *pList, /* List to which to append. Might be NULL */ 001640 IdList *pColumns, /* List of names of LHS of the assignment */ 001641 Expr *pExpr /* Vector expression to be appended. Might be NULL */ 001642 ){ 001643 sqlite3 *db = pParse->db; 001644 int n; 001645 int i; 001646 int iFirst = pList ? pList->nExpr : 0; 001647 /* pColumns can only be NULL due to an OOM but an OOM will cause an 001648 ** exit prior to this routine being invoked */ 001649 if( NEVER(pColumns==0) ) goto vector_append_error; 001650 if( pExpr==0 ) goto vector_append_error; 001651 001652 /* If the RHS is a vector, then we can immediately check to see that 001653 ** the size of the RHS and LHS match. But if the RHS is a SELECT, 001654 ** wildcards ("*") in the result set of the SELECT must be expanded before 001655 ** we can do the size check, so defer the size check until code generation. 001656 */ 001657 if( pExpr->op!=TK_SELECT && pColumns->nId!=(n=sqlite3ExprVectorSize(pExpr)) ){ 001658 sqlite3ErrorMsg(pParse, "%d columns assigned %d values", 001659 pColumns->nId, n); 001660 goto vector_append_error; 001661 } 001662 001663 for(i=0; i<pColumns->nId; i++){ 001664 Expr *pSubExpr = sqlite3ExprForVectorField(pParse, pExpr, i); 001665 assert( pSubExpr!=0 || db->mallocFailed ); 001666 assert( pSubExpr==0 || pSubExpr->iTable==0 ); 001667 if( pSubExpr==0 ) continue; 001668 pSubExpr->iTable = pColumns->nId; 001669 pList = sqlite3ExprListAppend(pParse, pList, pSubExpr); 001670 if( pList ){ 001671 assert( pList->nExpr==iFirst+i+1 ); 001672 pList->a[pList->nExpr-1].zName = pColumns->a[i].zName; 001673 pColumns->a[i].zName = 0; 001674 } 001675 } 001676 001677 if( !db->mallocFailed && pExpr->op==TK_SELECT && ALWAYS(pList!=0) ){ 001678 Expr *pFirst = pList->a[iFirst].pExpr; 001679 assert( pFirst!=0 ); 001680 assert( pFirst->op==TK_SELECT_COLUMN ); 001681 001682 /* Store the SELECT statement in pRight so it will be deleted when 001683 ** sqlite3ExprListDelete() is called */ 001684 pFirst->pRight = pExpr; 001685 pExpr = 0; 001686 001687 /* Remember the size of the LHS in iTable so that we can check that 001688 ** the RHS and LHS sizes match during code generation. */ 001689 pFirst->iTable = pColumns->nId; 001690 } 001691 001692 vector_append_error: 001693 sqlite3ExprUnmapAndDelete(pParse, pExpr); 001694 sqlite3IdListDelete(db, pColumns); 001695 return pList; 001696 } 001697 001698 /* 001699 ** Set the sort order for the last element on the given ExprList. 001700 */ 001701 void sqlite3ExprListSetSortOrder(ExprList *p, int iSortOrder, int eNulls){ 001702 struct ExprList_item *pItem; 001703 if( p==0 ) return; 001704 assert( p->nExpr>0 ); 001705 001706 assert( SQLITE_SO_UNDEFINED<0 && SQLITE_SO_ASC==0 && SQLITE_SO_DESC>0 ); 001707 assert( iSortOrder==SQLITE_SO_UNDEFINED 001708 || iSortOrder==SQLITE_SO_ASC 001709 || iSortOrder==SQLITE_SO_DESC 001710 ); 001711 assert( eNulls==SQLITE_SO_UNDEFINED 001712 || eNulls==SQLITE_SO_ASC 001713 || eNulls==SQLITE_SO_DESC 001714 ); 001715 001716 pItem = &p->a[p->nExpr-1]; 001717 assert( pItem->bNulls==0 ); 001718 if( iSortOrder==SQLITE_SO_UNDEFINED ){ 001719 iSortOrder = SQLITE_SO_ASC; 001720 } 001721 pItem->sortFlags = (u8)iSortOrder; 001722 001723 if( eNulls!=SQLITE_SO_UNDEFINED ){ 001724 pItem->bNulls = 1; 001725 if( iSortOrder!=eNulls ){ 001726 pItem->sortFlags |= KEYINFO_ORDER_BIGNULL; 001727 } 001728 } 001729 } 001730 001731 /* 001732 ** Set the ExprList.a[].zName element of the most recently added item 001733 ** on the expression list. 001734 ** 001735 ** pList might be NULL following an OOM error. But pName should never be 001736 ** NULL. If a memory allocation fails, the pParse->db->mallocFailed flag 001737 ** is set. 001738 */ 001739 void sqlite3ExprListSetName( 001740 Parse *pParse, /* Parsing context */ 001741 ExprList *pList, /* List to which to add the span. */ 001742 Token *pName, /* Name to be added */ 001743 int dequote /* True to cause the name to be dequoted */ 001744 ){ 001745 assert( pList!=0 || pParse->db->mallocFailed!=0 ); 001746 if( pList ){ 001747 struct ExprList_item *pItem; 001748 assert( pList->nExpr>0 ); 001749 pItem = &pList->a[pList->nExpr-1]; 001750 assert( pItem->zName==0 ); 001751 pItem->zName = sqlite3DbStrNDup(pParse->db, pName->z, pName->n); 001752 if( dequote ) sqlite3Dequote(pItem->zName); 001753 if( IN_RENAME_OBJECT ){ 001754 sqlite3RenameTokenMap(pParse, (void*)pItem->zName, pName); 001755 } 001756 } 001757 } 001758 001759 /* 001760 ** Set the ExprList.a[].zSpan element of the most recently added item 001761 ** on the expression list. 001762 ** 001763 ** pList might be NULL following an OOM error. But pSpan should never be 001764 ** NULL. If a memory allocation fails, the pParse->db->mallocFailed flag 001765 ** is set. 001766 */ 001767 void sqlite3ExprListSetSpan( 001768 Parse *pParse, /* Parsing context */ 001769 ExprList *pList, /* List to which to add the span. */ 001770 const char *zStart, /* Start of the span */ 001771 const char *zEnd /* End of the span */ 001772 ){ 001773 sqlite3 *db = pParse->db; 001774 assert( pList!=0 || db->mallocFailed!=0 ); 001775 if( pList ){ 001776 struct ExprList_item *pItem = &pList->a[pList->nExpr-1]; 001777 assert( pList->nExpr>0 ); 001778 sqlite3DbFree(db, pItem->zSpan); 001779 pItem->zSpan = sqlite3DbSpanDup(db, zStart, zEnd); 001780 } 001781 } 001782 001783 /* 001784 ** If the expression list pEList contains more than iLimit elements, 001785 ** leave an error message in pParse. 001786 */ 001787 void sqlite3ExprListCheckLength( 001788 Parse *pParse, 001789 ExprList *pEList, 001790 const char *zObject 001791 ){ 001792 int mx = pParse->db->aLimit[SQLITE_LIMIT_COLUMN]; 001793 testcase( pEList && pEList->nExpr==mx ); 001794 testcase( pEList && pEList->nExpr==mx+1 ); 001795 if( pEList && pEList->nExpr>mx ){ 001796 sqlite3ErrorMsg(pParse, "too many columns in %s", zObject); 001797 } 001798 } 001799 001800 /* 001801 ** Delete an entire expression list. 001802 */ 001803 static SQLITE_NOINLINE void exprListDeleteNN(sqlite3 *db, ExprList *pList){ 001804 int i = pList->nExpr; 001805 struct ExprList_item *pItem = pList->a; 001806 assert( pList->nExpr>0 ); 001807 do{ 001808 sqlite3ExprDelete(db, pItem->pExpr); 001809 sqlite3DbFree(db, pItem->zName); 001810 sqlite3DbFree(db, pItem->zSpan); 001811 pItem++; 001812 }while( --i>0 ); 001813 sqlite3DbFreeNN(db, pList); 001814 } 001815 void sqlite3ExprListDelete(sqlite3 *db, ExprList *pList){ 001816 if( pList ) exprListDeleteNN(db, pList); 001817 } 001818 001819 /* 001820 ** Return the bitwise-OR of all Expr.flags fields in the given 001821 ** ExprList. 001822 */ 001823 u32 sqlite3ExprListFlags(const ExprList *pList){ 001824 int i; 001825 u32 m = 0; 001826 assert( pList!=0 ); 001827 for(i=0; i<pList->nExpr; i++){ 001828 Expr *pExpr = pList->a[i].pExpr; 001829 assert( pExpr!=0 ); 001830 m |= pExpr->flags; 001831 } 001832 return m; 001833 } 001834 001835 /* 001836 ** This is a SELECT-node callback for the expression walker that 001837 ** always "fails". By "fail" in this case, we mean set 001838 ** pWalker->eCode to zero and abort. 001839 ** 001840 ** This callback is used by multiple expression walkers. 001841 */ 001842 int sqlite3SelectWalkFail(Walker *pWalker, Select *NotUsed){ 001843 UNUSED_PARAMETER(NotUsed); 001844 pWalker->eCode = 0; 001845 return WRC_Abort; 001846 } 001847 001848 /* 001849 ** If the input expression is an ID with the name "true" or "false" 001850 ** then convert it into an TK_TRUEFALSE term. Return non-zero if 001851 ** the conversion happened, and zero if the expression is unaltered. 001852 */ 001853 int sqlite3ExprIdToTrueFalse(Expr *pExpr){ 001854 assert( pExpr->op==TK_ID || pExpr->op==TK_STRING ); 001855 if( !ExprHasProperty(pExpr, EP_Quoted) 001856 && (sqlite3StrICmp(pExpr->u.zToken, "true")==0 001857 || sqlite3StrICmp(pExpr->u.zToken, "false")==0) 001858 ){ 001859 pExpr->op = TK_TRUEFALSE; 001860 ExprSetProperty(pExpr, pExpr->u.zToken[4]==0 ? EP_IsTrue : EP_IsFalse); 001861 return 1; 001862 } 001863 return 0; 001864 } 001865 001866 /* 001867 ** The argument must be a TK_TRUEFALSE Expr node. Return 1 if it is TRUE 001868 ** and 0 if it is FALSE. 001869 */ 001870 int sqlite3ExprTruthValue(const Expr *pExpr){ 001871 pExpr = sqlite3ExprSkipCollate((Expr*)pExpr); 001872 assert( pExpr->op==TK_TRUEFALSE ); 001873 assert( sqlite3StrICmp(pExpr->u.zToken,"true")==0 001874 || sqlite3StrICmp(pExpr->u.zToken,"false")==0 ); 001875 return pExpr->u.zToken[4]==0; 001876 } 001877 001878 /* 001879 ** If pExpr is an AND or OR expression, try to simplify it by eliminating 001880 ** terms that are always true or false. Return the simplified expression. 001881 ** Or return the original expression if no simplification is possible. 001882 ** 001883 ** Examples: 001884 ** 001885 ** (x<10) AND true => (x<10) 001886 ** (x<10) AND false => false 001887 ** (x<10) AND (y=22 OR false) => (x<10) AND (y=22) 001888 ** (x<10) AND (y=22 OR true) => (x<10) 001889 ** (y=22) OR true => true 001890 */ 001891 Expr *sqlite3ExprSimplifiedAndOr(Expr *pExpr){ 001892 assert( pExpr!=0 ); 001893 if( pExpr->op==TK_AND || pExpr->op==TK_OR ){ 001894 Expr *pRight = sqlite3ExprSimplifiedAndOr(pExpr->pRight); 001895 Expr *pLeft = sqlite3ExprSimplifiedAndOr(pExpr->pLeft); 001896 if( ExprAlwaysTrue(pLeft) || ExprAlwaysFalse(pRight) ){ 001897 pExpr = pExpr->op==TK_AND ? pRight : pLeft; 001898 }else if( ExprAlwaysTrue(pRight) || ExprAlwaysFalse(pLeft) ){ 001899 pExpr = pExpr->op==TK_AND ? pLeft : pRight; 001900 } 001901 } 001902 return pExpr; 001903 } 001904 001905 001906 /* 001907 ** These routines are Walker callbacks used to check expressions to 001908 ** see if they are "constant" for some definition of constant. The 001909 ** Walker.eCode value determines the type of "constant" we are looking 001910 ** for. 001911 ** 001912 ** These callback routines are used to implement the following: 001913 ** 001914 ** sqlite3ExprIsConstant() pWalker->eCode==1 001915 ** sqlite3ExprIsConstantNotJoin() pWalker->eCode==2 001916 ** sqlite3ExprIsTableConstant() pWalker->eCode==3 001917 ** sqlite3ExprIsConstantOrFunction() pWalker->eCode==4 or 5 001918 ** 001919 ** In all cases, the callbacks set Walker.eCode=0 and abort if the expression 001920 ** is found to not be a constant. 001921 ** 001922 ** The sqlite3ExprIsConstantOrFunction() is used for evaluating expressions 001923 ** in a CREATE TABLE statement. The Walker.eCode value is 5 when parsing 001924 ** an existing schema and 4 when processing a new statement. A bound 001925 ** parameter raises an error for new statements, but is silently converted 001926 ** to NULL for existing schemas. This allows sqlite_master tables that 001927 ** contain a bound parameter because they were generated by older versions 001928 ** of SQLite to be parsed by newer versions of SQLite without raising a 001929 ** malformed schema error. 001930 */ 001931 static int exprNodeIsConstant(Walker *pWalker, Expr *pExpr){ 001932 001933 /* If pWalker->eCode is 2 then any term of the expression that comes from 001934 ** the ON or USING clauses of a left join disqualifies the expression 001935 ** from being considered constant. */ 001936 if( pWalker->eCode==2 && ExprHasProperty(pExpr, EP_FromJoin) ){ 001937 pWalker->eCode = 0; 001938 return WRC_Abort; 001939 } 001940 001941 switch( pExpr->op ){ 001942 /* Consider functions to be constant if all their arguments are constant 001943 ** and either pWalker->eCode==4 or 5 or the function has the 001944 ** SQLITE_FUNC_CONST flag. */ 001945 case TK_FUNCTION: 001946 if( (pWalker->eCode>=4 || ExprHasProperty(pExpr,EP_ConstFunc)) 001947 && !ExprHasProperty(pExpr, EP_WinFunc) 001948 ){ 001949 return WRC_Continue; 001950 }else{ 001951 pWalker->eCode = 0; 001952 return WRC_Abort; 001953 } 001954 case TK_ID: 001955 /* Convert "true" or "false" in a DEFAULT clause into the 001956 ** appropriate TK_TRUEFALSE operator */ 001957 if( sqlite3ExprIdToTrueFalse(pExpr) ){ 001958 return WRC_Prune; 001959 } 001960 /* Fall thru */ 001961 case TK_COLUMN: 001962 case TK_AGG_FUNCTION: 001963 case TK_AGG_COLUMN: 001964 testcase( pExpr->op==TK_ID ); 001965 testcase( pExpr->op==TK_COLUMN ); 001966 testcase( pExpr->op==TK_AGG_FUNCTION ); 001967 testcase( pExpr->op==TK_AGG_COLUMN ); 001968 if( ExprHasProperty(pExpr, EP_FixedCol) && pWalker->eCode!=2 ){ 001969 return WRC_Continue; 001970 } 001971 if( pWalker->eCode==3 && pExpr->iTable==pWalker->u.iCur ){ 001972 return WRC_Continue; 001973 } 001974 /* Fall through */ 001975 case TK_IF_NULL_ROW: 001976 case TK_REGISTER: 001977 testcase( pExpr->op==TK_REGISTER ); 001978 testcase( pExpr->op==TK_IF_NULL_ROW ); 001979 pWalker->eCode = 0; 001980 return WRC_Abort; 001981 case TK_VARIABLE: 001982 if( pWalker->eCode==5 ){ 001983 /* Silently convert bound parameters that appear inside of CREATE 001984 ** statements into a NULL when parsing the CREATE statement text out 001985 ** of the sqlite_master table */ 001986 pExpr->op = TK_NULL; 001987 }else if( pWalker->eCode==4 ){ 001988 /* A bound parameter in a CREATE statement that originates from 001989 ** sqlite3_prepare() causes an error */ 001990 pWalker->eCode = 0; 001991 return WRC_Abort; 001992 } 001993 /* Fall through */ 001994 default: 001995 testcase( pExpr->op==TK_SELECT ); /* sqlite3SelectWalkFail() disallows */ 001996 testcase( pExpr->op==TK_EXISTS ); /* sqlite3SelectWalkFail() disallows */ 001997 return WRC_Continue; 001998 } 001999 } 002000 static int exprIsConst(Expr *p, int initFlag, int iCur){ 002001 Walker w; 002002 w.eCode = initFlag; 002003 w.xExprCallback = exprNodeIsConstant; 002004 w.xSelectCallback = sqlite3SelectWalkFail; 002005 #ifdef SQLITE_DEBUG 002006 w.xSelectCallback2 = sqlite3SelectWalkAssert2; 002007 #endif 002008 w.u.iCur = iCur; 002009 sqlite3WalkExpr(&w, p); 002010 return w.eCode; 002011 } 002012 002013 /* 002014 ** Walk an expression tree. Return non-zero if the expression is constant 002015 ** and 0 if it involves variables or function calls. 002016 ** 002017 ** For the purposes of this function, a double-quoted string (ex: "abc") 002018 ** is considered a variable but a single-quoted string (ex: 'abc') is 002019 ** a constant. 002020 */ 002021 int sqlite3ExprIsConstant(Expr *p){ 002022 return exprIsConst(p, 1, 0); 002023 } 002024 002025 /* 002026 ** Walk an expression tree. Return non-zero if 002027 ** 002028 ** (1) the expression is constant, and 002029 ** (2) the expression does originate in the ON or USING clause 002030 ** of a LEFT JOIN, and 002031 ** (3) the expression does not contain any EP_FixedCol TK_COLUMN 002032 ** operands created by the constant propagation optimization. 002033 ** 002034 ** When this routine returns true, it indicates that the expression 002035 ** can be added to the pParse->pConstExpr list and evaluated once when 002036 ** the prepared statement starts up. See sqlite3ExprCodeAtInit(). 002037 */ 002038 int sqlite3ExprIsConstantNotJoin(Expr *p){ 002039 return exprIsConst(p, 2, 0); 002040 } 002041 002042 /* 002043 ** Walk an expression tree. Return non-zero if the expression is constant 002044 ** for any single row of the table with cursor iCur. In other words, the 002045 ** expression must not refer to any non-deterministic function nor any 002046 ** table other than iCur. 002047 */ 002048 int sqlite3ExprIsTableConstant(Expr *p, int iCur){ 002049 return exprIsConst(p, 3, iCur); 002050 } 002051 002052 002053 /* 002054 ** sqlite3WalkExpr() callback used by sqlite3ExprIsConstantOrGroupBy(). 002055 */ 002056 static int exprNodeIsConstantOrGroupBy(Walker *pWalker, Expr *pExpr){ 002057 ExprList *pGroupBy = pWalker->u.pGroupBy; 002058 int i; 002059 002060 /* Check if pExpr is identical to any GROUP BY term. If so, consider 002061 ** it constant. */ 002062 for(i=0; i<pGroupBy->nExpr; i++){ 002063 Expr *p = pGroupBy->a[i].pExpr; 002064 if( sqlite3ExprCompare(0, pExpr, p, -1)<2 ){ 002065 CollSeq *pColl = sqlite3ExprNNCollSeq(pWalker->pParse, p); 002066 if( sqlite3IsBinary(pColl) ){ 002067 return WRC_Prune; 002068 } 002069 } 002070 } 002071 002072 /* Check if pExpr is a sub-select. If so, consider it variable. */ 002073 if( ExprHasProperty(pExpr, EP_xIsSelect) ){ 002074 pWalker->eCode = 0; 002075 return WRC_Abort; 002076 } 002077 002078 return exprNodeIsConstant(pWalker, pExpr); 002079 } 002080 002081 /* 002082 ** Walk the expression tree passed as the first argument. Return non-zero 002083 ** if the expression consists entirely of constants or copies of terms 002084 ** in pGroupBy that sort with the BINARY collation sequence. 002085 ** 002086 ** This routine is used to determine if a term of the HAVING clause can 002087 ** be promoted into the WHERE clause. In order for such a promotion to work, 002088 ** the value of the HAVING clause term must be the same for all members of 002089 ** a "group". The requirement that the GROUP BY term must be BINARY 002090 ** assumes that no other collating sequence will have a finer-grained 002091 ** grouping than binary. In other words (A=B COLLATE binary) implies 002092 ** A=B in every other collating sequence. The requirement that the 002093 ** GROUP BY be BINARY is stricter than necessary. It would also work 002094 ** to promote HAVING clauses that use the same alternative collating 002095 ** sequence as the GROUP BY term, but that is much harder to check, 002096 ** alternative collating sequences are uncommon, and this is only an 002097 ** optimization, so we take the easy way out and simply require the 002098 ** GROUP BY to use the BINARY collating sequence. 002099 */ 002100 int sqlite3ExprIsConstantOrGroupBy(Parse *pParse, Expr *p, ExprList *pGroupBy){ 002101 Walker w; 002102 w.eCode = 1; 002103 w.xExprCallback = exprNodeIsConstantOrGroupBy; 002104 w.xSelectCallback = 0; 002105 w.u.pGroupBy = pGroupBy; 002106 w.pParse = pParse; 002107 sqlite3WalkExpr(&w, p); 002108 return w.eCode; 002109 } 002110 002111 /* 002112 ** Walk an expression tree. Return non-zero if the expression is constant 002113 ** or a function call with constant arguments. Return and 0 if there 002114 ** are any variables. 002115 ** 002116 ** For the purposes of this function, a double-quoted string (ex: "abc") 002117 ** is considered a variable but a single-quoted string (ex: 'abc') is 002118 ** a constant. 002119 */ 002120 int sqlite3ExprIsConstantOrFunction(Expr *p, u8 isInit){ 002121 assert( isInit==0 || isInit==1 ); 002122 return exprIsConst(p, 4+isInit, 0); 002123 } 002124 002125 #ifdef SQLITE_ENABLE_CURSOR_HINTS 002126 /* 002127 ** Walk an expression tree. Return 1 if the expression contains a 002128 ** subquery of some kind. Return 0 if there are no subqueries. 002129 */ 002130 int sqlite3ExprContainsSubquery(Expr *p){ 002131 Walker w; 002132 w.eCode = 1; 002133 w.xExprCallback = sqlite3ExprWalkNoop; 002134 w.xSelectCallback = sqlite3SelectWalkFail; 002135 #ifdef SQLITE_DEBUG 002136 w.xSelectCallback2 = sqlite3SelectWalkAssert2; 002137 #endif 002138 sqlite3WalkExpr(&w, p); 002139 return w.eCode==0; 002140 } 002141 #endif 002142 002143 /* 002144 ** If the expression p codes a constant integer that is small enough 002145 ** to fit in a 32-bit integer, return 1 and put the value of the integer 002146 ** in *pValue. If the expression is not an integer or if it is too big 002147 ** to fit in a signed 32-bit integer, return 0 and leave *pValue unchanged. 002148 */ 002149 int sqlite3ExprIsInteger(Expr *p, int *pValue){ 002150 int rc = 0; 002151 if( NEVER(p==0) ) return 0; /* Used to only happen following on OOM */ 002152 002153 /* If an expression is an integer literal that fits in a signed 32-bit 002154 ** integer, then the EP_IntValue flag will have already been set */ 002155 assert( p->op!=TK_INTEGER || (p->flags & EP_IntValue)!=0 002156 || sqlite3GetInt32(p->u.zToken, &rc)==0 ); 002157 002158 if( p->flags & EP_IntValue ){ 002159 *pValue = p->u.iValue; 002160 return 1; 002161 } 002162 switch( p->op ){ 002163 case TK_UPLUS: { 002164 rc = sqlite3ExprIsInteger(p->pLeft, pValue); 002165 break; 002166 } 002167 case TK_UMINUS: { 002168 int v; 002169 if( sqlite3ExprIsInteger(p->pLeft, &v) ){ 002170 assert( v!=(-2147483647-1) ); 002171 *pValue = -v; 002172 rc = 1; 002173 } 002174 break; 002175 } 002176 default: break; 002177 } 002178 return rc; 002179 } 002180 002181 /* 002182 ** Return FALSE if there is no chance that the expression can be NULL. 002183 ** 002184 ** If the expression might be NULL or if the expression is too complex 002185 ** to tell return TRUE. 002186 ** 002187 ** This routine is used as an optimization, to skip OP_IsNull opcodes 002188 ** when we know that a value cannot be NULL. Hence, a false positive 002189 ** (returning TRUE when in fact the expression can never be NULL) might 002190 ** be a small performance hit but is otherwise harmless. On the other 002191 ** hand, a false negative (returning FALSE when the result could be NULL) 002192 ** will likely result in an incorrect answer. So when in doubt, return 002193 ** TRUE. 002194 */ 002195 int sqlite3ExprCanBeNull(const Expr *p){ 002196 u8 op; 002197 while( p->op==TK_UPLUS || p->op==TK_UMINUS ){ 002198 p = p->pLeft; 002199 } 002200 op = p->op; 002201 if( op==TK_REGISTER ) op = p->op2; 002202 switch( op ){ 002203 case TK_INTEGER: 002204 case TK_STRING: 002205 case TK_FLOAT: 002206 case TK_BLOB: 002207 return 0; 002208 case TK_COLUMN: 002209 return ExprHasProperty(p, EP_CanBeNull) || 002210 p->y.pTab==0 || /* Reference to column of index on expression */ 002211 (p->iColumn>=0 002212 && ALWAYS(p->y.pTab->aCol!=0) /* Defense against OOM problems */ 002213 && p->y.pTab->aCol[p->iColumn].notNull==0); 002214 default: 002215 return 1; 002216 } 002217 } 002218 002219 /* 002220 ** Return TRUE if the given expression is a constant which would be 002221 ** unchanged by OP_Affinity with the affinity given in the second 002222 ** argument. 002223 ** 002224 ** This routine is used to determine if the OP_Affinity operation 002225 ** can be omitted. When in doubt return FALSE. A false negative 002226 ** is harmless. A false positive, however, can result in the wrong 002227 ** answer. 002228 */ 002229 int sqlite3ExprNeedsNoAffinityChange(const Expr *p, char aff){ 002230 u8 op; 002231 int unaryMinus = 0; 002232 if( aff==SQLITE_AFF_BLOB ) return 1; 002233 while( p->op==TK_UPLUS || p->op==TK_UMINUS ){ 002234 if( p->op==TK_UMINUS ) unaryMinus = 1; 002235 p = p->pLeft; 002236 } 002237 op = p->op; 002238 if( op==TK_REGISTER ) op = p->op2; 002239 switch( op ){ 002240 case TK_INTEGER: { 002241 return aff>=SQLITE_AFF_NUMERIC; 002242 } 002243 case TK_FLOAT: { 002244 return aff>=SQLITE_AFF_NUMERIC; 002245 } 002246 case TK_STRING: { 002247 return !unaryMinus && aff==SQLITE_AFF_TEXT; 002248 } 002249 case TK_BLOB: { 002250 return !unaryMinus; 002251 } 002252 case TK_COLUMN: { 002253 assert( p->iTable>=0 ); /* p cannot be part of a CHECK constraint */ 002254 return aff>=SQLITE_AFF_NUMERIC && p->iColumn<0; 002255 } 002256 default: { 002257 return 0; 002258 } 002259 } 002260 } 002261 002262 /* 002263 ** Return TRUE if the given string is a row-id column name. 002264 */ 002265 int sqlite3IsRowid(const char *z){ 002266 if( sqlite3StrICmp(z, "_ROWID_")==0 ) return 1; 002267 if( sqlite3StrICmp(z, "ROWID")==0 ) return 1; 002268 if( sqlite3StrICmp(z, "OID")==0 ) return 1; 002269 return 0; 002270 } 002271 002272 /* 002273 ** pX is the RHS of an IN operator. If pX is a SELECT statement 002274 ** that can be simplified to a direct table access, then return 002275 ** a pointer to the SELECT statement. If pX is not a SELECT statement, 002276 ** or if the SELECT statement needs to be manifested into a transient 002277 ** table, then return NULL. 002278 */ 002279 #ifndef SQLITE_OMIT_SUBQUERY 002280 static Select *isCandidateForInOpt(Expr *pX){ 002281 Select *p; 002282 SrcList *pSrc; 002283 ExprList *pEList; 002284 Table *pTab; 002285 int i; 002286 if( !ExprHasProperty(pX, EP_xIsSelect) ) return 0; /* Not a subquery */ 002287 if( ExprHasProperty(pX, EP_VarSelect) ) return 0; /* Correlated subq */ 002288 p = pX->x.pSelect; 002289 if( p->pPrior ) return 0; /* Not a compound SELECT */ 002290 if( p->selFlags & (SF_Distinct|SF_Aggregate) ){ 002291 testcase( (p->selFlags & (SF_Distinct|SF_Aggregate))==SF_Distinct ); 002292 testcase( (p->selFlags & (SF_Distinct|SF_Aggregate))==SF_Aggregate ); 002293 return 0; /* No DISTINCT keyword and no aggregate functions */ 002294 } 002295 if( p->pGroupBy ) return 0; /* Has no GROUP BY clause */ 002296 if( p->pLimit ) return 0; /* Has no LIMIT clause */ 002297 if( p->pWhere ) return 0; /* Has no WHERE clause */ 002298 pSrc = p->pSrc; 002299 assert( pSrc!=0 ); 002300 if( pSrc->nSrc!=1 ) return 0; /* Single term in FROM clause */ 002301 if( pSrc->a[0].pSelect ) return 0; /* FROM is not a subquery or view */ 002302 pTab = pSrc->a[0].pTab; 002303 assert( pTab!=0 ); 002304 assert( pTab->pSelect==0 ); /* FROM clause is not a view */ 002305 if( IsVirtual(pTab) ) return 0; /* FROM clause not a virtual table */ 002306 pEList = p->pEList; 002307 assert( pEList!=0 ); 002308 /* All SELECT results must be columns. */ 002309 for(i=0; i<pEList->nExpr; i++){ 002310 Expr *pRes = pEList->a[i].pExpr; 002311 if( pRes->op!=TK_COLUMN ) return 0; 002312 assert( pRes->iTable==pSrc->a[0].iCursor ); /* Not a correlated subquery */ 002313 } 002314 return p; 002315 } 002316 #endif /* SQLITE_OMIT_SUBQUERY */ 002317 002318 #ifndef SQLITE_OMIT_SUBQUERY 002319 /* 002320 ** Generate code that checks the left-most column of index table iCur to see if 002321 ** it contains any NULL entries. Cause the register at regHasNull to be set 002322 ** to a non-NULL value if iCur contains no NULLs. Cause register regHasNull 002323 ** to be set to NULL if iCur contains one or more NULL values. 002324 */ 002325 static void sqlite3SetHasNullFlag(Vdbe *v, int iCur, int regHasNull){ 002326 int addr1; 002327 sqlite3VdbeAddOp2(v, OP_Integer, 0, regHasNull); 002328 addr1 = sqlite3VdbeAddOp1(v, OP_Rewind, iCur); VdbeCoverage(v); 002329 sqlite3VdbeAddOp3(v, OP_Column, iCur, 0, regHasNull); 002330 sqlite3VdbeChangeP5(v, OPFLAG_TYPEOFARG); 002331 VdbeComment((v, "first_entry_in(%d)", iCur)); 002332 sqlite3VdbeJumpHere(v, addr1); 002333 } 002334 #endif 002335 002336 002337 #ifndef SQLITE_OMIT_SUBQUERY 002338 /* 002339 ** The argument is an IN operator with a list (not a subquery) on the 002340 ** right-hand side. Return TRUE if that list is constant. 002341 */ 002342 static int sqlite3InRhsIsConstant(Expr *pIn){ 002343 Expr *pLHS; 002344 int res; 002345 assert( !ExprHasProperty(pIn, EP_xIsSelect) ); 002346 pLHS = pIn->pLeft; 002347 pIn->pLeft = 0; 002348 res = sqlite3ExprIsConstant(pIn); 002349 pIn->pLeft = pLHS; 002350 return res; 002351 } 002352 #endif 002353 002354 /* 002355 ** This function is used by the implementation of the IN (...) operator. 002356 ** The pX parameter is the expression on the RHS of the IN operator, which 002357 ** might be either a list of expressions or a subquery. 002358 ** 002359 ** The job of this routine is to find or create a b-tree object that can 002360 ** be used either to test for membership in the RHS set or to iterate through 002361 ** all members of the RHS set, skipping duplicates. 002362 ** 002363 ** A cursor is opened on the b-tree object that is the RHS of the IN operator 002364 ** and pX->iTable is set to the index of that cursor. 002365 ** 002366 ** The returned value of this function indicates the b-tree type, as follows: 002367 ** 002368 ** IN_INDEX_ROWID - The cursor was opened on a database table. 002369 ** IN_INDEX_INDEX_ASC - The cursor was opened on an ascending index. 002370 ** IN_INDEX_INDEX_DESC - The cursor was opened on a descending index. 002371 ** IN_INDEX_EPH - The cursor was opened on a specially created and 002372 ** populated epheremal table. 002373 ** IN_INDEX_NOOP - No cursor was allocated. The IN operator must be 002374 ** implemented as a sequence of comparisons. 002375 ** 002376 ** An existing b-tree might be used if the RHS expression pX is a simple 002377 ** subquery such as: 002378 ** 002379 ** SELECT <column1>, <column2>... FROM <table> 002380 ** 002381 ** If the RHS of the IN operator is a list or a more complex subquery, then 002382 ** an ephemeral table might need to be generated from the RHS and then 002383 ** pX->iTable made to point to the ephemeral table instead of an 002384 ** existing table. 002385 ** 002386 ** The inFlags parameter must contain, at a minimum, one of the bits 002387 ** IN_INDEX_MEMBERSHIP or IN_INDEX_LOOP but not both. If inFlags contains 002388 ** IN_INDEX_MEMBERSHIP, then the generated table will be used for a fast 002389 ** membership test. When the IN_INDEX_LOOP bit is set, the IN index will 002390 ** be used to loop over all values of the RHS of the IN operator. 002391 ** 002392 ** When IN_INDEX_LOOP is used (and the b-tree will be used to iterate 002393 ** through the set members) then the b-tree must not contain duplicates. 002394 ** An epheremal table will be created unless the selected columns are guaranteed 002395 ** to be unique - either because it is an INTEGER PRIMARY KEY or due to 002396 ** a UNIQUE constraint or index. 002397 ** 002398 ** When IN_INDEX_MEMBERSHIP is used (and the b-tree will be used 002399 ** for fast set membership tests) then an epheremal table must 002400 ** be used unless <columns> is a single INTEGER PRIMARY KEY column or an 002401 ** index can be found with the specified <columns> as its left-most. 002402 ** 002403 ** If the IN_INDEX_NOOP_OK and IN_INDEX_MEMBERSHIP are both set and 002404 ** if the RHS of the IN operator is a list (not a subquery) then this 002405 ** routine might decide that creating an ephemeral b-tree for membership 002406 ** testing is too expensive and return IN_INDEX_NOOP. In that case, the 002407 ** calling routine should implement the IN operator using a sequence 002408 ** of Eq or Ne comparison operations. 002409 ** 002410 ** When the b-tree is being used for membership tests, the calling function 002411 ** might need to know whether or not the RHS side of the IN operator 002412 ** contains a NULL. If prRhsHasNull is not a NULL pointer and 002413 ** if there is any chance that the (...) might contain a NULL value at 002414 ** runtime, then a register is allocated and the register number written 002415 ** to *prRhsHasNull. If there is no chance that the (...) contains a 002416 ** NULL value, then *prRhsHasNull is left unchanged. 002417 ** 002418 ** If a register is allocated and its location stored in *prRhsHasNull, then 002419 ** the value in that register will be NULL if the b-tree contains one or more 002420 ** NULL values, and it will be some non-NULL value if the b-tree contains no 002421 ** NULL values. 002422 ** 002423 ** If the aiMap parameter is not NULL, it must point to an array containing 002424 ** one element for each column returned by the SELECT statement on the RHS 002425 ** of the IN(...) operator. The i'th entry of the array is populated with the 002426 ** offset of the index column that matches the i'th column returned by the 002427 ** SELECT. For example, if the expression and selected index are: 002428 ** 002429 ** (?,?,?) IN (SELECT a, b, c FROM t1) 002430 ** CREATE INDEX i1 ON t1(b, c, a); 002431 ** 002432 ** then aiMap[] is populated with {2, 0, 1}. 002433 */ 002434 #ifndef SQLITE_OMIT_SUBQUERY 002435 int sqlite3FindInIndex( 002436 Parse *pParse, /* Parsing context */ 002437 Expr *pX, /* The IN expression */ 002438 u32 inFlags, /* IN_INDEX_LOOP, _MEMBERSHIP, and/or _NOOP_OK */ 002439 int *prRhsHasNull, /* Register holding NULL status. See notes */ 002440 int *aiMap, /* Mapping from Index fields to RHS fields */ 002441 int *piTab /* OUT: index to use */ 002442 ){ 002443 Select *p; /* SELECT to the right of IN operator */ 002444 int eType = 0; /* Type of RHS table. IN_INDEX_* */ 002445 int iTab = pParse->nTab++; /* Cursor of the RHS table */ 002446 int mustBeUnique; /* True if RHS must be unique */ 002447 Vdbe *v = sqlite3GetVdbe(pParse); /* Virtual machine being coded */ 002448 002449 assert( pX->op==TK_IN ); 002450 mustBeUnique = (inFlags & IN_INDEX_LOOP)!=0; 002451 002452 /* If the RHS of this IN(...) operator is a SELECT, and if it matters 002453 ** whether or not the SELECT result contains NULL values, check whether 002454 ** or not NULL is actually possible (it may not be, for example, due 002455 ** to NOT NULL constraints in the schema). If no NULL values are possible, 002456 ** set prRhsHasNull to 0 before continuing. */ 002457 if( prRhsHasNull && (pX->flags & EP_xIsSelect) ){ 002458 int i; 002459 ExprList *pEList = pX->x.pSelect->pEList; 002460 for(i=0; i<pEList->nExpr; i++){ 002461 if( sqlite3ExprCanBeNull(pEList->a[i].pExpr) ) break; 002462 } 002463 if( i==pEList->nExpr ){ 002464 prRhsHasNull = 0; 002465 } 002466 } 002467 002468 /* Check to see if an existing table or index can be used to 002469 ** satisfy the query. This is preferable to generating a new 002470 ** ephemeral table. */ 002471 if( pParse->nErr==0 && (p = isCandidateForInOpt(pX))!=0 ){ 002472 sqlite3 *db = pParse->db; /* Database connection */ 002473 Table *pTab; /* Table <table>. */ 002474 i16 iDb; /* Database idx for pTab */ 002475 ExprList *pEList = p->pEList; 002476 int nExpr = pEList->nExpr; 002477 002478 assert( p->pEList!=0 ); /* Because of isCandidateForInOpt(p) */ 002479 assert( p->pEList->a[0].pExpr!=0 ); /* Because of isCandidateForInOpt(p) */ 002480 assert( p->pSrc!=0 ); /* Because of isCandidateForInOpt(p) */ 002481 pTab = p->pSrc->a[0].pTab; 002482 002483 /* Code an OP_Transaction and OP_TableLock for <table>. */ 002484 iDb = sqlite3SchemaToIndex(db, pTab->pSchema); 002485 sqlite3CodeVerifySchema(pParse, iDb); 002486 sqlite3TableLock(pParse, iDb, pTab->tnum, 0, pTab->zName); 002487 002488 assert(v); /* sqlite3GetVdbe() has always been previously called */ 002489 if( nExpr==1 && pEList->a[0].pExpr->iColumn<0 ){ 002490 /* The "x IN (SELECT rowid FROM table)" case */ 002491 int iAddr = sqlite3VdbeAddOp0(v, OP_Once); 002492 VdbeCoverage(v); 002493 002494 sqlite3OpenTable(pParse, iTab, iDb, pTab, OP_OpenRead); 002495 eType = IN_INDEX_ROWID; 002496 ExplainQueryPlan((pParse, 0, 002497 "USING ROWID SEARCH ON TABLE %s FOR IN-OPERATOR",pTab->zName)); 002498 sqlite3VdbeJumpHere(v, iAddr); 002499 }else{ 002500 Index *pIdx; /* Iterator variable */ 002501 int affinity_ok = 1; 002502 int i; 002503 002504 /* Check that the affinity that will be used to perform each 002505 ** comparison is the same as the affinity of each column in table 002506 ** on the RHS of the IN operator. If it not, it is not possible to 002507 ** use any index of the RHS table. */ 002508 for(i=0; i<nExpr && affinity_ok; i++){ 002509 Expr *pLhs = sqlite3VectorFieldSubexpr(pX->pLeft, i); 002510 int iCol = pEList->a[i].pExpr->iColumn; 002511 char idxaff = sqlite3TableColumnAffinity(pTab,iCol); /* RHS table */ 002512 char cmpaff = sqlite3CompareAffinity(pLhs, idxaff); 002513 testcase( cmpaff==SQLITE_AFF_BLOB ); 002514 testcase( cmpaff==SQLITE_AFF_TEXT ); 002515 switch( cmpaff ){ 002516 case SQLITE_AFF_BLOB: 002517 break; 002518 case SQLITE_AFF_TEXT: 002519 /* sqlite3CompareAffinity() only returns TEXT if one side or the 002520 ** other has no affinity and the other side is TEXT. Hence, 002521 ** the only way for cmpaff to be TEXT is for idxaff to be TEXT 002522 ** and for the term on the LHS of the IN to have no affinity. */ 002523 assert( idxaff==SQLITE_AFF_TEXT ); 002524 break; 002525 default: 002526 affinity_ok = sqlite3IsNumericAffinity(idxaff); 002527 } 002528 } 002529 002530 if( affinity_ok ){ 002531 /* Search for an existing index that will work for this IN operator */ 002532 for(pIdx=pTab->pIndex; pIdx && eType==0; pIdx=pIdx->pNext){ 002533 Bitmask colUsed; /* Columns of the index used */ 002534 Bitmask mCol; /* Mask for the current column */ 002535 if( pIdx->nColumn<nExpr ) continue; 002536 if( pIdx->pPartIdxWhere!=0 ) continue; 002537 /* Maximum nColumn is BMS-2, not BMS-1, so that we can compute 002538 ** BITMASK(nExpr) without overflowing */ 002539 testcase( pIdx->nColumn==BMS-2 ); 002540 testcase( pIdx->nColumn==BMS-1 ); 002541 if( pIdx->nColumn>=BMS-1 ) continue; 002542 if( mustBeUnique ){ 002543 if( pIdx->nKeyCol>nExpr 002544 ||(pIdx->nColumn>nExpr && !IsUniqueIndex(pIdx)) 002545 ){ 002546 continue; /* This index is not unique over the IN RHS columns */ 002547 } 002548 } 002549 002550 colUsed = 0; /* Columns of index used so far */ 002551 for(i=0; i<nExpr; i++){ 002552 Expr *pLhs = sqlite3VectorFieldSubexpr(pX->pLeft, i); 002553 Expr *pRhs = pEList->a[i].pExpr; 002554 CollSeq *pReq = sqlite3BinaryCompareCollSeq(pParse, pLhs, pRhs); 002555 int j; 002556 002557 assert( pReq!=0 || pRhs->iColumn==XN_ROWID || pParse->nErr ); 002558 for(j=0; j<nExpr; j++){ 002559 if( pIdx->aiColumn[j]!=pRhs->iColumn ) continue; 002560 assert( pIdx->azColl[j] ); 002561 if( pReq!=0 && sqlite3StrICmp(pReq->zName, pIdx->azColl[j])!=0 ){ 002562 continue; 002563 } 002564 break; 002565 } 002566 if( j==nExpr ) break; 002567 mCol = MASKBIT(j); 002568 if( mCol & colUsed ) break; /* Each column used only once */ 002569 colUsed |= mCol; 002570 if( aiMap ) aiMap[i] = j; 002571 } 002572 002573 assert( i==nExpr || colUsed!=(MASKBIT(nExpr)-1) ); 002574 if( colUsed==(MASKBIT(nExpr)-1) ){ 002575 /* If we reach this point, that means the index pIdx is usable */ 002576 int iAddr = sqlite3VdbeAddOp0(v, OP_Once); VdbeCoverage(v); 002577 ExplainQueryPlan((pParse, 0, 002578 "USING INDEX %s FOR IN-OPERATOR",pIdx->zName)); 002579 sqlite3VdbeAddOp3(v, OP_OpenRead, iTab, pIdx->tnum, iDb); 002580 sqlite3VdbeSetP4KeyInfo(pParse, pIdx); 002581 VdbeComment((v, "%s", pIdx->zName)); 002582 assert( IN_INDEX_INDEX_DESC == IN_INDEX_INDEX_ASC+1 ); 002583 eType = IN_INDEX_INDEX_ASC + pIdx->aSortOrder[0]; 002584 002585 if( prRhsHasNull ){ 002586 #ifdef SQLITE_ENABLE_COLUMN_USED_MASK 002587 i64 mask = (1<<nExpr)-1; 002588 sqlite3VdbeAddOp4Dup8(v, OP_ColumnsUsed, 002589 iTab, 0, 0, (u8*)&mask, P4_INT64); 002590 #endif 002591 *prRhsHasNull = ++pParse->nMem; 002592 if( nExpr==1 ){ 002593 sqlite3SetHasNullFlag(v, iTab, *prRhsHasNull); 002594 } 002595 } 002596 sqlite3VdbeJumpHere(v, iAddr); 002597 } 002598 } /* End loop over indexes */ 002599 } /* End if( affinity_ok ) */ 002600 } /* End if not an rowid index */ 002601 } /* End attempt to optimize using an index */ 002602 002603 /* If no preexisting index is available for the IN clause 002604 ** and IN_INDEX_NOOP is an allowed reply 002605 ** and the RHS of the IN operator is a list, not a subquery 002606 ** and the RHS is not constant or has two or fewer terms, 002607 ** then it is not worth creating an ephemeral table to evaluate 002608 ** the IN operator so return IN_INDEX_NOOP. 002609 */ 002610 if( eType==0 002611 && (inFlags & IN_INDEX_NOOP_OK) 002612 && !ExprHasProperty(pX, EP_xIsSelect) 002613 && (!sqlite3InRhsIsConstant(pX) || pX->x.pList->nExpr<=2) 002614 ){ 002615 eType = IN_INDEX_NOOP; 002616 } 002617 002618 if( eType==0 ){ 002619 /* Could not find an existing table or index to use as the RHS b-tree. 002620 ** We will have to generate an ephemeral table to do the job. 002621 */ 002622 u32 savedNQueryLoop = pParse->nQueryLoop; 002623 int rMayHaveNull = 0; 002624 eType = IN_INDEX_EPH; 002625 if( inFlags & IN_INDEX_LOOP ){ 002626 pParse->nQueryLoop = 0; 002627 }else if( prRhsHasNull ){ 002628 *prRhsHasNull = rMayHaveNull = ++pParse->nMem; 002629 } 002630 assert( pX->op==TK_IN ); 002631 sqlite3CodeRhsOfIN(pParse, pX, iTab); 002632 if( rMayHaveNull ){ 002633 sqlite3SetHasNullFlag(v, iTab, rMayHaveNull); 002634 } 002635 pParse->nQueryLoop = savedNQueryLoop; 002636 } 002637 002638 if( aiMap && eType!=IN_INDEX_INDEX_ASC && eType!=IN_INDEX_INDEX_DESC ){ 002639 int i, n; 002640 n = sqlite3ExprVectorSize(pX->pLeft); 002641 for(i=0; i<n; i++) aiMap[i] = i; 002642 } 002643 *piTab = iTab; 002644 return eType; 002645 } 002646 #endif 002647 002648 #ifndef SQLITE_OMIT_SUBQUERY 002649 /* 002650 ** Argument pExpr is an (?, ?...) IN(...) expression. This 002651 ** function allocates and returns a nul-terminated string containing 002652 ** the affinities to be used for each column of the comparison. 002653 ** 002654 ** It is the responsibility of the caller to ensure that the returned 002655 ** string is eventually freed using sqlite3DbFree(). 002656 */ 002657 static char *exprINAffinity(Parse *pParse, Expr *pExpr){ 002658 Expr *pLeft = pExpr->pLeft; 002659 int nVal = sqlite3ExprVectorSize(pLeft); 002660 Select *pSelect = (pExpr->flags & EP_xIsSelect) ? pExpr->x.pSelect : 0; 002661 char *zRet; 002662 002663 assert( pExpr->op==TK_IN ); 002664 zRet = sqlite3DbMallocRaw(pParse->db, nVal+1); 002665 if( zRet ){ 002666 int i; 002667 for(i=0; i<nVal; i++){ 002668 Expr *pA = sqlite3VectorFieldSubexpr(pLeft, i); 002669 char a = sqlite3ExprAffinity(pA); 002670 if( pSelect ){ 002671 zRet[i] = sqlite3CompareAffinity(pSelect->pEList->a[i].pExpr, a); 002672 }else{ 002673 zRet[i] = a; 002674 } 002675 } 002676 zRet[nVal] = '\0'; 002677 } 002678 return zRet; 002679 } 002680 #endif 002681 002682 #ifndef SQLITE_OMIT_SUBQUERY 002683 /* 002684 ** Load the Parse object passed as the first argument with an error 002685 ** message of the form: 002686 ** 002687 ** "sub-select returns N columns - expected M" 002688 */ 002689 void sqlite3SubselectError(Parse *pParse, int nActual, int nExpect){ 002690 if( pParse->nErr==0 ){ 002691 const char *zFmt = "sub-select returns %d columns - expected %d"; 002692 sqlite3ErrorMsg(pParse, zFmt, nActual, nExpect); 002693 } 002694 } 002695 #endif 002696 002697 /* 002698 ** Expression pExpr is a vector that has been used in a context where 002699 ** it is not permitted. If pExpr is a sub-select vector, this routine 002700 ** loads the Parse object with a message of the form: 002701 ** 002702 ** "sub-select returns N columns - expected 1" 002703 ** 002704 ** Or, if it is a regular scalar vector: 002705 ** 002706 ** "row value misused" 002707 */ 002708 void sqlite3VectorErrorMsg(Parse *pParse, Expr *pExpr){ 002709 #ifndef SQLITE_OMIT_SUBQUERY 002710 if( pExpr->flags & EP_xIsSelect ){ 002711 sqlite3SubselectError(pParse, pExpr->x.pSelect->pEList->nExpr, 1); 002712 }else 002713 #endif 002714 { 002715 sqlite3ErrorMsg(pParse, "row value misused"); 002716 } 002717 } 002718 002719 #ifndef SQLITE_OMIT_SUBQUERY 002720 /* 002721 ** Generate code that will construct an ephemeral table containing all terms 002722 ** in the RHS of an IN operator. The IN operator can be in either of two 002723 ** forms: 002724 ** 002725 ** x IN (4,5,11) -- IN operator with list on right-hand side 002726 ** x IN (SELECT a FROM b) -- IN operator with subquery on the right 002727 ** 002728 ** The pExpr parameter is the IN operator. The cursor number for the 002729 ** constructed ephermeral table is returned. The first time the ephemeral 002730 ** table is computed, the cursor number is also stored in pExpr->iTable, 002731 ** however the cursor number returned might not be the same, as it might 002732 ** have been duplicated using OP_OpenDup. 002733 ** 002734 ** If the LHS expression ("x" in the examples) is a column value, or 002735 ** the SELECT statement returns a column value, then the affinity of that 002736 ** column is used to build the index keys. If both 'x' and the 002737 ** SELECT... statement are columns, then numeric affinity is used 002738 ** if either column has NUMERIC or INTEGER affinity. If neither 002739 ** 'x' nor the SELECT... statement are columns, then numeric affinity 002740 ** is used. 002741 */ 002742 void sqlite3CodeRhsOfIN( 002743 Parse *pParse, /* Parsing context */ 002744 Expr *pExpr, /* The IN operator */ 002745 int iTab /* Use this cursor number */ 002746 ){ 002747 int addrOnce = 0; /* Address of the OP_Once instruction at top */ 002748 int addr; /* Address of OP_OpenEphemeral instruction */ 002749 Expr *pLeft; /* the LHS of the IN operator */ 002750 KeyInfo *pKeyInfo = 0; /* Key information */ 002751 int nVal; /* Size of vector pLeft */ 002752 Vdbe *v; /* The prepared statement under construction */ 002753 002754 v = pParse->pVdbe; 002755 assert( v!=0 ); 002756 002757 /* The evaluation of the IN must be repeated every time it 002758 ** is encountered if any of the following is true: 002759 ** 002760 ** * The right-hand side is a correlated subquery 002761 ** * The right-hand side is an expression list containing variables 002762 ** * We are inside a trigger 002763 ** 002764 ** If all of the above are false, then we can compute the RHS just once 002765 ** and reuse it many names. 002766 */ 002767 if( !ExprHasProperty(pExpr, EP_VarSelect) && pParse->iSelfTab==0 ){ 002768 /* Reuse of the RHS is allowed */ 002769 /* If this routine has already been coded, but the previous code 002770 ** might not have been invoked yet, so invoke it now as a subroutine. 002771 */ 002772 if( ExprHasProperty(pExpr, EP_Subrtn) ){ 002773 addrOnce = sqlite3VdbeAddOp0(v, OP_Once); VdbeCoverage(v); 002774 if( ExprHasProperty(pExpr, EP_xIsSelect) ){ 002775 ExplainQueryPlan((pParse, 0, "REUSE LIST SUBQUERY %d", 002776 pExpr->x.pSelect->selId)); 002777 } 002778 sqlite3VdbeAddOp2(v, OP_Gosub, pExpr->y.sub.regReturn, 002779 pExpr->y.sub.iAddr); 002780 sqlite3VdbeAddOp2(v, OP_OpenDup, iTab, pExpr->iTable); 002781 sqlite3VdbeJumpHere(v, addrOnce); 002782 return; 002783 } 002784 002785 /* Begin coding the subroutine */ 002786 ExprSetProperty(pExpr, EP_Subrtn); 002787 pExpr->y.sub.regReturn = ++pParse->nMem; 002788 pExpr->y.sub.iAddr = 002789 sqlite3VdbeAddOp2(v, OP_Integer, 0, pExpr->y.sub.regReturn) + 1; 002790 VdbeComment((v, "return address")); 002791 002792 addrOnce = sqlite3VdbeAddOp0(v, OP_Once); VdbeCoverage(v); 002793 } 002794 002795 /* Check to see if this is a vector IN operator */ 002796 pLeft = pExpr->pLeft; 002797 nVal = sqlite3ExprVectorSize(pLeft); 002798 002799 /* Construct the ephemeral table that will contain the content of 002800 ** RHS of the IN operator. 002801 */ 002802 pExpr->iTable = iTab; 002803 addr = sqlite3VdbeAddOp2(v, OP_OpenEphemeral, pExpr->iTable, nVal); 002804 #ifdef SQLITE_ENABLE_EXPLAIN_COMMENTS 002805 if( ExprHasProperty(pExpr, EP_xIsSelect) ){ 002806 VdbeComment((v, "Result of SELECT %u", pExpr->x.pSelect->selId)); 002807 }else{ 002808 VdbeComment((v, "RHS of IN operator")); 002809 } 002810 #endif 002811 pKeyInfo = sqlite3KeyInfoAlloc(pParse->db, nVal, 1); 002812 002813 if( ExprHasProperty(pExpr, EP_xIsSelect) ){ 002814 /* Case 1: expr IN (SELECT ...) 002815 ** 002816 ** Generate code to write the results of the select into the temporary 002817 ** table allocated and opened above. 002818 */ 002819 Select *pSelect = pExpr->x.pSelect; 002820 ExprList *pEList = pSelect->pEList; 002821 002822 ExplainQueryPlan((pParse, 1, "%sLIST SUBQUERY %d", 002823 addrOnce?"":"CORRELATED ", pSelect->selId 002824 )); 002825 /* If the LHS and RHS of the IN operator do not match, that 002826 ** error will have been caught long before we reach this point. */ 002827 if( ALWAYS(pEList->nExpr==nVal) ){ 002828 SelectDest dest; 002829 int i; 002830 sqlite3SelectDestInit(&dest, SRT_Set, iTab); 002831 dest.zAffSdst = exprINAffinity(pParse, pExpr); 002832 pSelect->iLimit = 0; 002833 testcase( pSelect->selFlags & SF_Distinct ); 002834 testcase( pKeyInfo==0 ); /* Caused by OOM in sqlite3KeyInfoAlloc() */ 002835 if( sqlite3Select(pParse, pSelect, &dest) ){ 002836 sqlite3DbFree(pParse->db, dest.zAffSdst); 002837 sqlite3KeyInfoUnref(pKeyInfo); 002838 return; 002839 } 002840 sqlite3DbFree(pParse->db, dest.zAffSdst); 002841 assert( pKeyInfo!=0 ); /* OOM will cause exit after sqlite3Select() */ 002842 assert( pEList!=0 ); 002843 assert( pEList->nExpr>0 ); 002844 assert( sqlite3KeyInfoIsWriteable(pKeyInfo) ); 002845 for(i=0; i<nVal; i++){ 002846 Expr *p = sqlite3VectorFieldSubexpr(pLeft, i); 002847 pKeyInfo->aColl[i] = sqlite3BinaryCompareCollSeq( 002848 pParse, p, pEList->a[i].pExpr 002849 ); 002850 } 002851 } 002852 }else if( ALWAYS(pExpr->x.pList!=0) ){ 002853 /* Case 2: expr IN (exprlist) 002854 ** 002855 ** For each expression, build an index key from the evaluation and 002856 ** store it in the temporary table. If <expr> is a column, then use 002857 ** that columns affinity when building index keys. If <expr> is not 002858 ** a column, use numeric affinity. 002859 */ 002860 char affinity; /* Affinity of the LHS of the IN */ 002861 int i; 002862 ExprList *pList = pExpr->x.pList; 002863 struct ExprList_item *pItem; 002864 int r1, r2; 002865 affinity = sqlite3ExprAffinity(pLeft); 002866 if( affinity<=SQLITE_AFF_NONE ){ 002867 affinity = SQLITE_AFF_BLOB; 002868 } 002869 if( pKeyInfo ){ 002870 assert( sqlite3KeyInfoIsWriteable(pKeyInfo) ); 002871 pKeyInfo->aColl[0] = sqlite3ExprCollSeq(pParse, pExpr->pLeft); 002872 } 002873 002874 /* Loop through each expression in <exprlist>. */ 002875 r1 = sqlite3GetTempReg(pParse); 002876 r2 = sqlite3GetTempReg(pParse); 002877 for(i=pList->nExpr, pItem=pList->a; i>0; i--, pItem++){ 002878 Expr *pE2 = pItem->pExpr; 002879 002880 /* If the expression is not constant then we will need to 002881 ** disable the test that was generated above that makes sure 002882 ** this code only executes once. Because for a non-constant 002883 ** expression we need to rerun this code each time. 002884 */ 002885 if( addrOnce && !sqlite3ExprIsConstant(pE2) ){ 002886 sqlite3VdbeChangeToNoop(v, addrOnce); 002887 ExprClearProperty(pExpr, EP_Subrtn); 002888 addrOnce = 0; 002889 } 002890 002891 /* Evaluate the expression and insert it into the temp table */ 002892 sqlite3ExprCode(pParse, pE2, r1); 002893 sqlite3VdbeAddOp4(v, OP_MakeRecord, r1, 1, r2, &affinity, 1); 002894 sqlite3VdbeAddOp4Int(v, OP_IdxInsert, iTab, r2, r1, 1); 002895 } 002896 sqlite3ReleaseTempReg(pParse, r1); 002897 sqlite3ReleaseTempReg(pParse, r2); 002898 } 002899 if( pKeyInfo ){ 002900 sqlite3VdbeChangeP4(v, addr, (void *)pKeyInfo, P4_KEYINFO); 002901 } 002902 if( addrOnce ){ 002903 sqlite3VdbeJumpHere(v, addrOnce); 002904 /* Subroutine return */ 002905 sqlite3VdbeAddOp1(v, OP_Return, pExpr->y.sub.regReturn); 002906 sqlite3VdbeChangeP1(v, pExpr->y.sub.iAddr-1, sqlite3VdbeCurrentAddr(v)-1); 002907 sqlite3ClearTempRegCache(pParse); 002908 } 002909 } 002910 #endif /* SQLITE_OMIT_SUBQUERY */ 002911 002912 /* 002913 ** Generate code for scalar subqueries used as a subquery expression 002914 ** or EXISTS operator: 002915 ** 002916 ** (SELECT a FROM b) -- subquery 002917 ** EXISTS (SELECT a FROM b) -- EXISTS subquery 002918 ** 002919 ** The pExpr parameter is the SELECT or EXISTS operator to be coded. 002920 ** 002921 ** Return the register that holds the result. For a multi-column SELECT, 002922 ** the result is stored in a contiguous array of registers and the 002923 ** return value is the register of the left-most result column. 002924 ** Return 0 if an error occurs. 002925 */ 002926 #ifndef SQLITE_OMIT_SUBQUERY 002927 int sqlite3CodeSubselect(Parse *pParse, Expr *pExpr){ 002928 int addrOnce = 0; /* Address of OP_Once at top of subroutine */ 002929 int rReg = 0; /* Register storing resulting */ 002930 Select *pSel; /* SELECT statement to encode */ 002931 SelectDest dest; /* How to deal with SELECT result */ 002932 int nReg; /* Registers to allocate */ 002933 Expr *pLimit; /* New limit expression */ 002934 002935 Vdbe *v = pParse->pVdbe; 002936 assert( v!=0 ); 002937 testcase( pExpr->op==TK_EXISTS ); 002938 testcase( pExpr->op==TK_SELECT ); 002939 assert( pExpr->op==TK_EXISTS || pExpr->op==TK_SELECT ); 002940 assert( ExprHasProperty(pExpr, EP_xIsSelect) ); 002941 pSel = pExpr->x.pSelect; 002942 002943 /* The evaluation of the EXISTS/SELECT must be repeated every time it 002944 ** is encountered if any of the following is true: 002945 ** 002946 ** * The right-hand side is a correlated subquery 002947 ** * The right-hand side is an expression list containing variables 002948 ** * We are inside a trigger 002949 ** 002950 ** If all of the above are false, then we can run this code just once 002951 ** save the results, and reuse the same result on subsequent invocations. 002952 */ 002953 if( !ExprHasProperty(pExpr, EP_VarSelect) ){ 002954 /* If this routine has already been coded, then invoke it as a 002955 ** subroutine. */ 002956 if( ExprHasProperty(pExpr, EP_Subrtn) ){ 002957 ExplainQueryPlan((pParse, 0, "REUSE SUBQUERY %d", pSel->selId)); 002958 sqlite3VdbeAddOp2(v, OP_Gosub, pExpr->y.sub.regReturn, 002959 pExpr->y.sub.iAddr); 002960 return pExpr->iTable; 002961 } 002962 002963 /* Begin coding the subroutine */ 002964 ExprSetProperty(pExpr, EP_Subrtn); 002965 pExpr->y.sub.regReturn = ++pParse->nMem; 002966 pExpr->y.sub.iAddr = 002967 sqlite3VdbeAddOp2(v, OP_Integer, 0, pExpr->y.sub.regReturn) + 1; 002968 VdbeComment((v, "return address")); 002969 002970 addrOnce = sqlite3VdbeAddOp0(v, OP_Once); VdbeCoverage(v); 002971 } 002972 002973 /* For a SELECT, generate code to put the values for all columns of 002974 ** the first row into an array of registers and return the index of 002975 ** the first register. 002976 ** 002977 ** If this is an EXISTS, write an integer 0 (not exists) or 1 (exists) 002978 ** into a register and return that register number. 002979 ** 002980 ** In both cases, the query is augmented with "LIMIT 1". Any 002981 ** preexisting limit is discarded in place of the new LIMIT 1. 002982 */ 002983 ExplainQueryPlan((pParse, 1, "%sSCALAR SUBQUERY %d", 002984 addrOnce?"":"CORRELATED ", pSel->selId)); 002985 nReg = pExpr->op==TK_SELECT ? pSel->pEList->nExpr : 1; 002986 sqlite3SelectDestInit(&dest, 0, pParse->nMem+1); 002987 pParse->nMem += nReg; 002988 if( pExpr->op==TK_SELECT ){ 002989 dest.eDest = SRT_Mem; 002990 dest.iSdst = dest.iSDParm; 002991 dest.nSdst = nReg; 002992 sqlite3VdbeAddOp3(v, OP_Null, 0, dest.iSDParm, dest.iSDParm+nReg-1); 002993 VdbeComment((v, "Init subquery result")); 002994 }else{ 002995 dest.eDest = SRT_Exists; 002996 sqlite3VdbeAddOp2(v, OP_Integer, 0, dest.iSDParm); 002997 VdbeComment((v, "Init EXISTS result")); 002998 } 002999 if( pSel->pLimit ){ 003000 /* The subquery already has a limit. If the pre-existing limit is X 003001 ** then make the new limit X<>0 so that the new limit is either 1 or 0 */ 003002 sqlite3 *db = pParse->db; 003003 pLimit = sqlite3Expr(db, TK_INTEGER, "0"); 003004 if( pLimit ){ 003005 pLimit->affExpr = SQLITE_AFF_NUMERIC; 003006 pLimit = sqlite3PExpr(pParse, TK_NE, 003007 sqlite3ExprDup(db, pSel->pLimit->pLeft, 0), pLimit); 003008 } 003009 sqlite3ExprDelete(db, pSel->pLimit->pLeft); 003010 pSel->pLimit->pLeft = pLimit; 003011 }else{ 003012 /* If there is no pre-existing limit add a limit of 1 */ 003013 pLimit = sqlite3Expr(pParse->db, TK_INTEGER, "1"); 003014 pSel->pLimit = sqlite3PExpr(pParse, TK_LIMIT, pLimit, 0); 003015 } 003016 pSel->iLimit = 0; 003017 if( sqlite3Select(pParse, pSel, &dest) ){ 003018 return 0; 003019 } 003020 pExpr->iTable = rReg = dest.iSDParm; 003021 ExprSetVVAProperty(pExpr, EP_NoReduce); 003022 if( addrOnce ){ 003023 sqlite3VdbeJumpHere(v, addrOnce); 003024 003025 /* Subroutine return */ 003026 sqlite3VdbeAddOp1(v, OP_Return, pExpr->y.sub.regReturn); 003027 sqlite3VdbeChangeP1(v, pExpr->y.sub.iAddr-1, sqlite3VdbeCurrentAddr(v)-1); 003028 sqlite3ClearTempRegCache(pParse); 003029 } 003030 003031 return rReg; 003032 } 003033 #endif /* SQLITE_OMIT_SUBQUERY */ 003034 003035 #ifndef SQLITE_OMIT_SUBQUERY 003036 /* 003037 ** Expr pIn is an IN(...) expression. This function checks that the 003038 ** sub-select on the RHS of the IN() operator has the same number of 003039 ** columns as the vector on the LHS. Or, if the RHS of the IN() is not 003040 ** a sub-query, that the LHS is a vector of size 1. 003041 */ 003042 int sqlite3ExprCheckIN(Parse *pParse, Expr *pIn){ 003043 int nVector = sqlite3ExprVectorSize(pIn->pLeft); 003044 if( (pIn->flags & EP_xIsSelect) ){ 003045 if( nVector!=pIn->x.pSelect->pEList->nExpr ){ 003046 sqlite3SubselectError(pParse, pIn->x.pSelect->pEList->nExpr, nVector); 003047 return 1; 003048 } 003049 }else if( nVector!=1 ){ 003050 sqlite3VectorErrorMsg(pParse, pIn->pLeft); 003051 return 1; 003052 } 003053 return 0; 003054 } 003055 #endif 003056 003057 #ifndef SQLITE_OMIT_SUBQUERY 003058 /* 003059 ** Generate code for an IN expression. 003060 ** 003061 ** x IN (SELECT ...) 003062 ** x IN (value, value, ...) 003063 ** 003064 ** The left-hand side (LHS) is a scalar or vector expression. The 003065 ** right-hand side (RHS) is an array of zero or more scalar values, or a 003066 ** subquery. If the RHS is a subquery, the number of result columns must 003067 ** match the number of columns in the vector on the LHS. If the RHS is 003068 ** a list of values, the LHS must be a scalar. 003069 ** 003070 ** The IN operator is true if the LHS value is contained within the RHS. 003071 ** The result is false if the LHS is definitely not in the RHS. The 003072 ** result is NULL if the presence of the LHS in the RHS cannot be 003073 ** determined due to NULLs. 003074 ** 003075 ** This routine generates code that jumps to destIfFalse if the LHS is not 003076 ** contained within the RHS. If due to NULLs we cannot determine if the LHS 003077 ** is contained in the RHS then jump to destIfNull. If the LHS is contained 003078 ** within the RHS then fall through. 003079 ** 003080 ** See the separate in-operator.md documentation file in the canonical 003081 ** SQLite source tree for additional information. 003082 */ 003083 static void sqlite3ExprCodeIN( 003084 Parse *pParse, /* Parsing and code generating context */ 003085 Expr *pExpr, /* The IN expression */ 003086 int destIfFalse, /* Jump here if LHS is not contained in the RHS */ 003087 int destIfNull /* Jump here if the results are unknown due to NULLs */ 003088 ){ 003089 int rRhsHasNull = 0; /* Register that is true if RHS contains NULL values */ 003090 int eType; /* Type of the RHS */ 003091 int rLhs; /* Register(s) holding the LHS values */ 003092 int rLhsOrig; /* LHS values prior to reordering by aiMap[] */ 003093 Vdbe *v; /* Statement under construction */ 003094 int *aiMap = 0; /* Map from vector field to index column */ 003095 char *zAff = 0; /* Affinity string for comparisons */ 003096 int nVector; /* Size of vectors for this IN operator */ 003097 int iDummy; /* Dummy parameter to exprCodeVector() */ 003098 Expr *pLeft; /* The LHS of the IN operator */ 003099 int i; /* loop counter */ 003100 int destStep2; /* Where to jump when NULLs seen in step 2 */ 003101 int destStep6 = 0; /* Start of code for Step 6 */ 003102 int addrTruthOp; /* Address of opcode that determines the IN is true */ 003103 int destNotNull; /* Jump here if a comparison is not true in step 6 */ 003104 int addrTop; /* Top of the step-6 loop */ 003105 int iTab = 0; /* Index to use */ 003106 003107 pLeft = pExpr->pLeft; 003108 if( sqlite3ExprCheckIN(pParse, pExpr) ) return; 003109 zAff = exprINAffinity(pParse, pExpr); 003110 nVector = sqlite3ExprVectorSize(pExpr->pLeft); 003111 aiMap = (int*)sqlite3DbMallocZero( 003112 pParse->db, nVector*(sizeof(int) + sizeof(char)) + 1 003113 ); 003114 if( pParse->db->mallocFailed ) goto sqlite3ExprCodeIN_oom_error; 003115 003116 /* Attempt to compute the RHS. After this step, if anything other than 003117 ** IN_INDEX_NOOP is returned, the table opened with cursor iTab 003118 ** contains the values that make up the RHS. If IN_INDEX_NOOP is returned, 003119 ** the RHS has not yet been coded. */ 003120 v = pParse->pVdbe; 003121 assert( v!=0 ); /* OOM detected prior to this routine */ 003122 VdbeNoopComment((v, "begin IN expr")); 003123 eType = sqlite3FindInIndex(pParse, pExpr, 003124 IN_INDEX_MEMBERSHIP | IN_INDEX_NOOP_OK, 003125 destIfFalse==destIfNull ? 0 : &rRhsHasNull, 003126 aiMap, &iTab); 003127 003128 assert( pParse->nErr || nVector==1 || eType==IN_INDEX_EPH 003129 || eType==IN_INDEX_INDEX_ASC || eType==IN_INDEX_INDEX_DESC 003130 ); 003131 #ifdef SQLITE_DEBUG 003132 /* Confirm that aiMap[] contains nVector integer values between 0 and 003133 ** nVector-1. */ 003134 for(i=0; i<nVector; i++){ 003135 int j, cnt; 003136 for(cnt=j=0; j<nVector; j++) if( aiMap[j]==i ) cnt++; 003137 assert( cnt==1 ); 003138 } 003139 #endif 003140 003141 /* Code the LHS, the <expr> from "<expr> IN (...)". If the LHS is a 003142 ** vector, then it is stored in an array of nVector registers starting 003143 ** at r1. 003144 ** 003145 ** sqlite3FindInIndex() might have reordered the fields of the LHS vector 003146 ** so that the fields are in the same order as an existing index. The 003147 ** aiMap[] array contains a mapping from the original LHS field order to 003148 ** the field order that matches the RHS index. 003149 */ 003150 rLhsOrig = exprCodeVector(pParse, pLeft, &iDummy); 003151 for(i=0; i<nVector && aiMap[i]==i; i++){} /* Are LHS fields reordered? */ 003152 if( i==nVector ){ 003153 /* LHS fields are not reordered */ 003154 rLhs = rLhsOrig; 003155 }else{ 003156 /* Need to reorder the LHS fields according to aiMap */ 003157 rLhs = sqlite3GetTempRange(pParse, nVector); 003158 for(i=0; i<nVector; i++){ 003159 sqlite3VdbeAddOp3(v, OP_Copy, rLhsOrig+i, rLhs+aiMap[i], 0); 003160 } 003161 } 003162 003163 /* If sqlite3FindInIndex() did not find or create an index that is 003164 ** suitable for evaluating the IN operator, then evaluate using a 003165 ** sequence of comparisons. 003166 ** 003167 ** This is step (1) in the in-operator.md optimized algorithm. 003168 */ 003169 if( eType==IN_INDEX_NOOP ){ 003170 ExprList *pList = pExpr->x.pList; 003171 CollSeq *pColl = sqlite3ExprCollSeq(pParse, pExpr->pLeft); 003172 int labelOk = sqlite3VdbeMakeLabel(pParse); 003173 int r2, regToFree; 003174 int regCkNull = 0; 003175 int ii; 003176 int bLhsReal; /* True if the LHS of the IN has REAL affinity */ 003177 assert( !ExprHasProperty(pExpr, EP_xIsSelect) ); 003178 if( destIfNull!=destIfFalse ){ 003179 regCkNull = sqlite3GetTempReg(pParse); 003180 sqlite3VdbeAddOp3(v, OP_BitAnd, rLhs, rLhs, regCkNull); 003181 } 003182 bLhsReal = sqlite3ExprAffinity(pExpr->pLeft)==SQLITE_AFF_REAL; 003183 for(ii=0; ii<pList->nExpr; ii++){ 003184 if( bLhsReal ){ 003185 r2 = regToFree = sqlite3GetTempReg(pParse); 003186 sqlite3ExprCode(pParse, pList->a[ii].pExpr, r2); 003187 sqlite3VdbeAddOp4(v, OP_Affinity, r2, 1, 0, "E", P4_STATIC); 003188 }else{ 003189 r2 = sqlite3ExprCodeTemp(pParse, pList->a[ii].pExpr, ®ToFree); 003190 } 003191 if( regCkNull && sqlite3ExprCanBeNull(pList->a[ii].pExpr) ){ 003192 sqlite3VdbeAddOp3(v, OP_BitAnd, regCkNull, r2, regCkNull); 003193 } 003194 if( ii<pList->nExpr-1 || destIfNull!=destIfFalse ){ 003195 int op = rLhs!=r2 ? OP_Eq : OP_NotNull; 003196 sqlite3VdbeAddOp4(v, op, rLhs, labelOk, r2, 003197 (void*)pColl, P4_COLLSEQ); 003198 VdbeCoverageIf(v, ii<pList->nExpr-1 && op==OP_Eq); 003199 VdbeCoverageIf(v, ii==pList->nExpr-1 && op==OP_Eq); 003200 VdbeCoverageIf(v, ii<pList->nExpr-1 && op==OP_NotNull); 003201 VdbeCoverageIf(v, ii==pList->nExpr-1 && op==OP_NotNull); 003202 sqlite3VdbeChangeP5(v, zAff[0]); 003203 }else{ 003204 int op = rLhs!=r2 ? OP_Ne : OP_IsNull; 003205 assert( destIfNull==destIfFalse ); 003206 sqlite3VdbeAddOp4(v, op, rLhs, destIfFalse, r2, 003207 (void*)pColl, P4_COLLSEQ); 003208 VdbeCoverageIf(v, op==OP_Ne); 003209 VdbeCoverageIf(v, op==OP_IsNull); 003210 sqlite3VdbeChangeP5(v, zAff[0] | SQLITE_JUMPIFNULL); 003211 } 003212 sqlite3ReleaseTempReg(pParse, regToFree); 003213 } 003214 if( regCkNull ){ 003215 sqlite3VdbeAddOp2(v, OP_IsNull, regCkNull, destIfNull); VdbeCoverage(v); 003216 sqlite3VdbeGoto(v, destIfFalse); 003217 } 003218 sqlite3VdbeResolveLabel(v, labelOk); 003219 sqlite3ReleaseTempReg(pParse, regCkNull); 003220 goto sqlite3ExprCodeIN_finished; 003221 } 003222 003223 /* Step 2: Check to see if the LHS contains any NULL columns. If the 003224 ** LHS does contain NULLs then the result must be either FALSE or NULL. 003225 ** We will then skip the binary search of the RHS. 003226 */ 003227 if( destIfNull==destIfFalse ){ 003228 destStep2 = destIfFalse; 003229 }else{ 003230 destStep2 = destStep6 = sqlite3VdbeMakeLabel(pParse); 003231 } 003232 if( pParse->nErr ) goto sqlite3ExprCodeIN_finished; 003233 for(i=0; i<nVector; i++){ 003234 Expr *p = sqlite3VectorFieldSubexpr(pExpr->pLeft, i); 003235 if( sqlite3ExprCanBeNull(p) ){ 003236 sqlite3VdbeAddOp2(v, OP_IsNull, rLhs+i, destStep2); 003237 VdbeCoverage(v); 003238 } 003239 } 003240 003241 /* Step 3. The LHS is now known to be non-NULL. Do the binary search 003242 ** of the RHS using the LHS as a probe. If found, the result is 003243 ** true. 003244 */ 003245 if( eType==IN_INDEX_ROWID ){ 003246 /* In this case, the RHS is the ROWID of table b-tree and so we also 003247 ** know that the RHS is non-NULL. Hence, we combine steps 3 and 4 003248 ** into a single opcode. */ 003249 sqlite3VdbeAddOp3(v, OP_SeekRowid, iTab, destIfFalse, rLhs); 003250 VdbeCoverage(v); 003251 addrTruthOp = sqlite3VdbeAddOp0(v, OP_Goto); /* Return True */ 003252 }else{ 003253 sqlite3VdbeAddOp4(v, OP_Affinity, rLhs, nVector, 0, zAff, nVector); 003254 if( destIfFalse==destIfNull ){ 003255 /* Combine Step 3 and Step 5 into a single opcode */ 003256 sqlite3VdbeAddOp4Int(v, OP_NotFound, iTab, destIfFalse, 003257 rLhs, nVector); VdbeCoverage(v); 003258 goto sqlite3ExprCodeIN_finished; 003259 } 003260 /* Ordinary Step 3, for the case where FALSE and NULL are distinct */ 003261 addrTruthOp = sqlite3VdbeAddOp4Int(v, OP_Found, iTab, 0, 003262 rLhs, nVector); VdbeCoverage(v); 003263 } 003264 003265 /* Step 4. If the RHS is known to be non-NULL and we did not find 003266 ** an match on the search above, then the result must be FALSE. 003267 */ 003268 if( rRhsHasNull && nVector==1 ){ 003269 sqlite3VdbeAddOp2(v, OP_NotNull, rRhsHasNull, destIfFalse); 003270 VdbeCoverage(v); 003271 } 003272 003273 /* Step 5. If we do not care about the difference between NULL and 003274 ** FALSE, then just return false. 003275 */ 003276 if( destIfFalse==destIfNull ) sqlite3VdbeGoto(v, destIfFalse); 003277 003278 /* Step 6: Loop through rows of the RHS. Compare each row to the LHS. 003279 ** If any comparison is NULL, then the result is NULL. If all 003280 ** comparisons are FALSE then the final result is FALSE. 003281 ** 003282 ** For a scalar LHS, it is sufficient to check just the first row 003283 ** of the RHS. 003284 */ 003285 if( destStep6 ) sqlite3VdbeResolveLabel(v, destStep6); 003286 addrTop = sqlite3VdbeAddOp2(v, OP_Rewind, iTab, destIfFalse); 003287 VdbeCoverage(v); 003288 if( nVector>1 ){ 003289 destNotNull = sqlite3VdbeMakeLabel(pParse); 003290 }else{ 003291 /* For nVector==1, combine steps 6 and 7 by immediately returning 003292 ** FALSE if the first comparison is not NULL */ 003293 destNotNull = destIfFalse; 003294 } 003295 for(i=0; i<nVector; i++){ 003296 Expr *p; 003297 CollSeq *pColl; 003298 int r3 = sqlite3GetTempReg(pParse); 003299 p = sqlite3VectorFieldSubexpr(pLeft, i); 003300 pColl = sqlite3ExprCollSeq(pParse, p); 003301 sqlite3VdbeAddOp3(v, OP_Column, iTab, i, r3); 003302 sqlite3VdbeAddOp4(v, OP_Ne, rLhs+i, destNotNull, r3, 003303 (void*)pColl, P4_COLLSEQ); 003304 VdbeCoverage(v); 003305 sqlite3ReleaseTempReg(pParse, r3); 003306 } 003307 sqlite3VdbeAddOp2(v, OP_Goto, 0, destIfNull); 003308 if( nVector>1 ){ 003309 sqlite3VdbeResolveLabel(v, destNotNull); 003310 sqlite3VdbeAddOp2(v, OP_Next, iTab, addrTop+1); 003311 VdbeCoverage(v); 003312 003313 /* Step 7: If we reach this point, we know that the result must 003314 ** be false. */ 003315 sqlite3VdbeAddOp2(v, OP_Goto, 0, destIfFalse); 003316 } 003317 003318 /* Jumps here in order to return true. */ 003319 sqlite3VdbeJumpHere(v, addrTruthOp); 003320 003321 sqlite3ExprCodeIN_finished: 003322 if( rLhs!=rLhsOrig ) sqlite3ReleaseTempReg(pParse, rLhs); 003323 VdbeComment((v, "end IN expr")); 003324 sqlite3ExprCodeIN_oom_error: 003325 sqlite3DbFree(pParse->db, aiMap); 003326 sqlite3DbFree(pParse->db, zAff); 003327 } 003328 #endif /* SQLITE_OMIT_SUBQUERY */ 003329 003330 #ifndef SQLITE_OMIT_FLOATING_POINT 003331 /* 003332 ** Generate an instruction that will put the floating point 003333 ** value described by z[0..n-1] into register iMem. 003334 ** 003335 ** The z[] string will probably not be zero-terminated. But the 003336 ** z[n] character is guaranteed to be something that does not look 003337 ** like the continuation of the number. 003338 */ 003339 static void codeReal(Vdbe *v, const char *z, int negateFlag, int iMem){ 003340 if( ALWAYS(z!=0) ){ 003341 double value; 003342 sqlite3AtoF(z, &value, sqlite3Strlen30(z), SQLITE_UTF8); 003343 assert( !sqlite3IsNaN(value) ); /* The new AtoF never returns NaN */ 003344 if( negateFlag ) value = -value; 003345 sqlite3VdbeAddOp4Dup8(v, OP_Real, 0, iMem, 0, (u8*)&value, P4_REAL); 003346 } 003347 } 003348 #endif 003349 003350 003351 /* 003352 ** Generate an instruction that will put the integer describe by 003353 ** text z[0..n-1] into register iMem. 003354 ** 003355 ** Expr.u.zToken is always UTF8 and zero-terminated. 003356 */ 003357 static void codeInteger(Parse *pParse, Expr *pExpr, int negFlag, int iMem){ 003358 Vdbe *v = pParse->pVdbe; 003359 if( pExpr->flags & EP_IntValue ){ 003360 int i = pExpr->u.iValue; 003361 assert( i>=0 ); 003362 if( negFlag ) i = -i; 003363 sqlite3VdbeAddOp2(v, OP_Integer, i, iMem); 003364 }else{ 003365 int c; 003366 i64 value; 003367 const char *z = pExpr->u.zToken; 003368 assert( z!=0 ); 003369 c = sqlite3DecOrHexToI64(z, &value); 003370 if( (c==3 && !negFlag) || (c==2) || (negFlag && value==SMALLEST_INT64)){ 003371 #ifdef SQLITE_OMIT_FLOATING_POINT 003372 sqlite3ErrorMsg(pParse, "oversized integer: %s%s", negFlag ? "-" : "", z); 003373 #else 003374 #ifndef SQLITE_OMIT_HEX_INTEGER 003375 if( sqlite3_strnicmp(z,"0x",2)==0 ){ 003376 sqlite3ErrorMsg(pParse, "hex literal too big: %s%s", negFlag?"-":"",z); 003377 }else 003378 #endif 003379 { 003380 codeReal(v, z, negFlag, iMem); 003381 } 003382 #endif 003383 }else{ 003384 if( negFlag ){ value = c==3 ? SMALLEST_INT64 : -value; } 003385 sqlite3VdbeAddOp4Dup8(v, OP_Int64, 0, iMem, 0, (u8*)&value, P4_INT64); 003386 } 003387 } 003388 } 003389 003390 003391 /* Generate code that will load into register regOut a value that is 003392 ** appropriate for the iIdxCol-th column of index pIdx. 003393 */ 003394 void sqlite3ExprCodeLoadIndexColumn( 003395 Parse *pParse, /* The parsing context */ 003396 Index *pIdx, /* The index whose column is to be loaded */ 003397 int iTabCur, /* Cursor pointing to a table row */ 003398 int iIdxCol, /* The column of the index to be loaded */ 003399 int regOut /* Store the index column value in this register */ 003400 ){ 003401 i16 iTabCol = pIdx->aiColumn[iIdxCol]; 003402 if( iTabCol==XN_EXPR ){ 003403 assert( pIdx->aColExpr ); 003404 assert( pIdx->aColExpr->nExpr>iIdxCol ); 003405 pParse->iSelfTab = iTabCur + 1; 003406 sqlite3ExprCodeCopy(pParse, pIdx->aColExpr->a[iIdxCol].pExpr, regOut); 003407 pParse->iSelfTab = 0; 003408 }else{ 003409 sqlite3ExprCodeGetColumnOfTable(pParse->pVdbe, pIdx->pTable, iTabCur, 003410 iTabCol, regOut); 003411 } 003412 } 003413 003414 #ifndef SQLITE_OMIT_GENERATED_COLUMNS 003415 /* 003416 ** Generate code that will compute the value of generated column pCol 003417 ** and store the result in register regOut 003418 */ 003419 void sqlite3ExprCodeGeneratedColumn( 003420 Parse *pParse, 003421 Column *pCol, 003422 int regOut 003423 ){ 003424 int iAddr; 003425 Vdbe *v = pParse->pVdbe; 003426 assert( v!=0 ); 003427 assert( pParse->iSelfTab!=0 ); 003428 if( pParse->iSelfTab>0 ){ 003429 iAddr = sqlite3VdbeAddOp3(v, OP_IfNullRow, pParse->iSelfTab-1, 0, regOut); 003430 }else{ 003431 iAddr = 0; 003432 } 003433 sqlite3ExprCode(pParse, pCol->pDflt, regOut); 003434 if( pCol->affinity>=SQLITE_AFF_TEXT ){ 003435 sqlite3VdbeAddOp4(v, OP_Affinity, regOut, 1, 0, &pCol->affinity, 1); 003436 } 003437 if( iAddr ) sqlite3VdbeJumpHere(v, iAddr); 003438 } 003439 #endif /* SQLITE_OMIT_GENERATED_COLUMNS */ 003440 003441 /* 003442 ** Generate code to extract the value of the iCol-th column of a table. 003443 */ 003444 void sqlite3ExprCodeGetColumnOfTable( 003445 Vdbe *v, /* Parsing context */ 003446 Table *pTab, /* The table containing the value */ 003447 int iTabCur, /* The table cursor. Or the PK cursor for WITHOUT ROWID */ 003448 int iCol, /* Index of the column to extract */ 003449 int regOut /* Extract the value into this register */ 003450 ){ 003451 Column *pCol; 003452 assert( v!=0 ); 003453 if( pTab==0 ){ 003454 sqlite3VdbeAddOp3(v, OP_Column, iTabCur, iCol, regOut); 003455 return; 003456 } 003457 if( iCol<0 || iCol==pTab->iPKey ){ 003458 sqlite3VdbeAddOp2(v, OP_Rowid, iTabCur, regOut); 003459 }else{ 003460 int op; 003461 int x; 003462 if( IsVirtual(pTab) ){ 003463 op = OP_VColumn; 003464 x = iCol; 003465 #ifndef SQLITE_OMIT_GENERATED_COLUMNS 003466 }else if( (pCol = &pTab->aCol[iCol])->colFlags & COLFLAG_VIRTUAL ){ 003467 Parse *pParse = sqlite3VdbeParser(v); 003468 if( pCol->colFlags & COLFLAG_BUSY ){ 003469 sqlite3ErrorMsg(pParse, "generated column loop on \"%s\"", pCol->zName); 003470 }else{ 003471 int savedSelfTab = pParse->iSelfTab; 003472 pCol->colFlags |= COLFLAG_BUSY; 003473 pParse->iSelfTab = iTabCur+1; 003474 sqlite3ExprCodeGeneratedColumn(pParse, pCol, regOut); 003475 pParse->iSelfTab = savedSelfTab; 003476 pCol->colFlags &= ~COLFLAG_BUSY; 003477 } 003478 return; 003479 #endif 003480 }else if( !HasRowid(pTab) ){ 003481 testcase( iCol!=sqlite3TableColumnToStorage(pTab, iCol) ); 003482 x = sqlite3TableColumnToIndex(sqlite3PrimaryKeyIndex(pTab), iCol); 003483 op = OP_Column; 003484 }else{ 003485 x = sqlite3TableColumnToStorage(pTab,iCol); 003486 testcase( x!=iCol ); 003487 op = OP_Column; 003488 } 003489 sqlite3VdbeAddOp3(v, op, iTabCur, x, regOut); 003490 sqlite3ColumnDefault(v, pTab, iCol, regOut); 003491 } 003492 } 003493 003494 /* 003495 ** Generate code that will extract the iColumn-th column from 003496 ** table pTab and store the column value in register iReg. 003497 ** 003498 ** There must be an open cursor to pTab in iTable when this routine 003499 ** is called. If iColumn<0 then code is generated that extracts the rowid. 003500 */ 003501 int sqlite3ExprCodeGetColumn( 003502 Parse *pParse, /* Parsing and code generating context */ 003503 Table *pTab, /* Description of the table we are reading from */ 003504 int iColumn, /* Index of the table column */ 003505 int iTable, /* The cursor pointing to the table */ 003506 int iReg, /* Store results here */ 003507 u8 p5 /* P5 value for OP_Column + FLAGS */ 003508 ){ 003509 assert( pParse->pVdbe!=0 ); 003510 sqlite3ExprCodeGetColumnOfTable(pParse->pVdbe, pTab, iTable, iColumn, iReg); 003511 if( p5 ){ 003512 VdbeOp *pOp = sqlite3VdbeGetOp(pParse->pVdbe,-1); 003513 if( pOp->opcode==OP_Column ) pOp->p5 = p5; 003514 } 003515 return iReg; 003516 } 003517 003518 /* 003519 ** Generate code to move content from registers iFrom...iFrom+nReg-1 003520 ** over to iTo..iTo+nReg-1. 003521 */ 003522 void sqlite3ExprCodeMove(Parse *pParse, int iFrom, int iTo, int nReg){ 003523 sqlite3VdbeAddOp3(pParse->pVdbe, OP_Move, iFrom, iTo, nReg); 003524 } 003525 003526 /* 003527 ** Convert a scalar expression node to a TK_REGISTER referencing 003528 ** register iReg. The caller must ensure that iReg already contains 003529 ** the correct value for the expression. 003530 */ 003531 static void exprToRegister(Expr *pExpr, int iReg){ 003532 Expr *p = sqlite3ExprSkipCollateAndLikely(pExpr); 003533 p->op2 = p->op; 003534 p->op = TK_REGISTER; 003535 p->iTable = iReg; 003536 ExprClearProperty(p, EP_Skip); 003537 } 003538 003539 /* 003540 ** Evaluate an expression (either a vector or a scalar expression) and store 003541 ** the result in continguous temporary registers. Return the index of 003542 ** the first register used to store the result. 003543 ** 003544 ** If the returned result register is a temporary scalar, then also write 003545 ** that register number into *piFreeable. If the returned result register 003546 ** is not a temporary or if the expression is a vector set *piFreeable 003547 ** to 0. 003548 */ 003549 static int exprCodeVector(Parse *pParse, Expr *p, int *piFreeable){ 003550 int iResult; 003551 int nResult = sqlite3ExprVectorSize(p); 003552 if( nResult==1 ){ 003553 iResult = sqlite3ExprCodeTemp(pParse, p, piFreeable); 003554 }else{ 003555 *piFreeable = 0; 003556 if( p->op==TK_SELECT ){ 003557 #if SQLITE_OMIT_SUBQUERY 003558 iResult = 0; 003559 #else 003560 iResult = sqlite3CodeSubselect(pParse, p); 003561 #endif 003562 }else{ 003563 int i; 003564 iResult = pParse->nMem+1; 003565 pParse->nMem += nResult; 003566 for(i=0; i<nResult; i++){ 003567 sqlite3ExprCodeFactorable(pParse, p->x.pList->a[i].pExpr, i+iResult); 003568 } 003569 } 003570 } 003571 return iResult; 003572 } 003573 003574 003575 /* 003576 ** Generate code into the current Vdbe to evaluate the given 003577 ** expression. Attempt to store the results in register "target". 003578 ** Return the register where results are stored. 003579 ** 003580 ** With this routine, there is no guarantee that results will 003581 ** be stored in target. The result might be stored in some other 003582 ** register if it is convenient to do so. The calling function 003583 ** must check the return code and move the results to the desired 003584 ** register. 003585 */ 003586 int sqlite3ExprCodeTarget(Parse *pParse, Expr *pExpr, int target){ 003587 Vdbe *v = pParse->pVdbe; /* The VM under construction */ 003588 int op; /* The opcode being coded */ 003589 int inReg = target; /* Results stored in register inReg */ 003590 int regFree1 = 0; /* If non-zero free this temporary register */ 003591 int regFree2 = 0; /* If non-zero free this temporary register */ 003592 int r1, r2; /* Various register numbers */ 003593 Expr tempX; /* Temporary expression node */ 003594 int p5 = 0; 003595 003596 assert( target>0 && target<=pParse->nMem ); 003597 if( v==0 ){ 003598 assert( pParse->db->mallocFailed ); 003599 return 0; 003600 } 003601 003602 expr_code_doover: 003603 if( pExpr==0 ){ 003604 op = TK_NULL; 003605 }else{ 003606 op = pExpr->op; 003607 } 003608 switch( op ){ 003609 case TK_AGG_COLUMN: { 003610 AggInfo *pAggInfo = pExpr->pAggInfo; 003611 struct AggInfo_col *pCol = &pAggInfo->aCol[pExpr->iAgg]; 003612 if( !pAggInfo->directMode ){ 003613 assert( pCol->iMem>0 ); 003614 return pCol->iMem; 003615 }else if( pAggInfo->useSortingIdx ){ 003616 sqlite3VdbeAddOp3(v, OP_Column, pAggInfo->sortingIdxPTab, 003617 pCol->iSorterColumn, target); 003618 return target; 003619 } 003620 /* Otherwise, fall thru into the TK_COLUMN case */ 003621 } 003622 case TK_COLUMN: { 003623 int iTab = pExpr->iTable; 003624 int iReg; 003625 if( ExprHasProperty(pExpr, EP_FixedCol) ){ 003626 /* This COLUMN expression is really a constant due to WHERE clause 003627 ** constraints, and that constant is coded by the pExpr->pLeft 003628 ** expresssion. However, make sure the constant has the correct 003629 ** datatype by applying the Affinity of the table column to the 003630 ** constant. 003631 */ 003632 int aff; 003633 iReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft,target); 003634 if( pExpr->y.pTab ){ 003635 aff = sqlite3TableColumnAffinity(pExpr->y.pTab, pExpr->iColumn); 003636 }else{ 003637 aff = pExpr->affExpr; 003638 } 003639 if( aff>SQLITE_AFF_BLOB ){ 003640 static const char zAff[] = "B\000C\000D\000E"; 003641 assert( SQLITE_AFF_BLOB=='A' ); 003642 assert( SQLITE_AFF_TEXT=='B' ); 003643 if( iReg!=target ){ 003644 sqlite3VdbeAddOp2(v, OP_SCopy, iReg, target); 003645 iReg = target; 003646 } 003647 sqlite3VdbeAddOp4(v, OP_Affinity, iReg, 1, 0, 003648 &zAff[(aff-'B')*2], P4_STATIC); 003649 } 003650 return iReg; 003651 } 003652 if( iTab<0 ){ 003653 if( pParse->iSelfTab<0 ){ 003654 /* Other columns in the same row for CHECK constraints or 003655 ** generated columns or for inserting into partial index. 003656 ** The row is unpacked into registers beginning at 003657 ** 0-(pParse->iSelfTab). The rowid (if any) is in a register 003658 ** immediately prior to the first column. 003659 */ 003660 Column *pCol; 003661 Table *pTab = pExpr->y.pTab; 003662 int iSrc; 003663 int iCol = pExpr->iColumn; 003664 assert( pTab!=0 ); 003665 assert( iCol>=XN_ROWID ); 003666 assert( iCol<pTab->nCol ); 003667 if( iCol<0 ){ 003668 return -1-pParse->iSelfTab; 003669 } 003670 pCol = pTab->aCol + iCol; 003671 testcase( iCol!=sqlite3TableColumnToStorage(pTab,iCol) ); 003672 iSrc = sqlite3TableColumnToStorage(pTab, iCol) - pParse->iSelfTab; 003673 #ifndef SQLITE_OMIT_GENERATED_COLUMNS 003674 if( pCol->colFlags & COLFLAG_GENERATED ){ 003675 if( pCol->colFlags & COLFLAG_BUSY ){ 003676 sqlite3ErrorMsg(pParse, "generated column loop on \"%s\"", 003677 pCol->zName); 003678 return 0; 003679 } 003680 pCol->colFlags |= COLFLAG_BUSY; 003681 if( pCol->colFlags & COLFLAG_NOTAVAIL ){ 003682 sqlite3ExprCodeGeneratedColumn(pParse, pCol, iSrc); 003683 } 003684 pCol->colFlags &= ~(COLFLAG_BUSY|COLFLAG_NOTAVAIL); 003685 return iSrc; 003686 }else 003687 #endif /* SQLITE_OMIT_GENERATED_COLUMNS */ 003688 if( pCol->affinity==SQLITE_AFF_REAL ){ 003689 sqlite3VdbeAddOp2(v, OP_SCopy, iSrc, target); 003690 sqlite3VdbeAddOp1(v, OP_RealAffinity, target); 003691 return target; 003692 }else{ 003693 return iSrc; 003694 } 003695 }else{ 003696 /* Coding an expression that is part of an index where column names 003697 ** in the index refer to the table to which the index belongs */ 003698 iTab = pParse->iSelfTab - 1; 003699 } 003700 } 003701 iReg = sqlite3ExprCodeGetColumn(pParse, pExpr->y.pTab, 003702 pExpr->iColumn, iTab, target, 003703 pExpr->op2); 003704 if( pExpr->y.pTab==0 && pExpr->affExpr==SQLITE_AFF_REAL ){ 003705 sqlite3VdbeAddOp1(v, OP_RealAffinity, iReg); 003706 } 003707 return iReg; 003708 } 003709 case TK_INTEGER: { 003710 codeInteger(pParse, pExpr, 0, target); 003711 return target; 003712 } 003713 case TK_TRUEFALSE: { 003714 sqlite3VdbeAddOp2(v, OP_Integer, sqlite3ExprTruthValue(pExpr), target); 003715 return target; 003716 } 003717 #ifndef SQLITE_OMIT_FLOATING_POINT 003718 case TK_FLOAT: { 003719 assert( !ExprHasProperty(pExpr, EP_IntValue) ); 003720 codeReal(v, pExpr->u.zToken, 0, target); 003721 return target; 003722 } 003723 #endif 003724 case TK_STRING: { 003725 assert( !ExprHasProperty(pExpr, EP_IntValue) ); 003726 sqlite3VdbeLoadString(v, target, pExpr->u.zToken); 003727 return target; 003728 } 003729 default: { 003730 /* Make NULL the default case so that if a bug causes an illegal 003731 ** Expr node to be passed into this function, it will be handled 003732 ** sanely and not crash. But keep the assert() to bring the problem 003733 ** to the attention of the developers. */ 003734 assert( op==TK_NULL ); 003735 sqlite3VdbeAddOp2(v, OP_Null, 0, target); 003736 return target; 003737 } 003738 #ifndef SQLITE_OMIT_BLOB_LITERAL 003739 case TK_BLOB: { 003740 int n; 003741 const char *z; 003742 char *zBlob; 003743 assert( !ExprHasProperty(pExpr, EP_IntValue) ); 003744 assert( pExpr->u.zToken[0]=='x' || pExpr->u.zToken[0]=='X' ); 003745 assert( pExpr->u.zToken[1]=='\'' ); 003746 z = &pExpr->u.zToken[2]; 003747 n = sqlite3Strlen30(z) - 1; 003748 assert( z[n]=='\'' ); 003749 zBlob = sqlite3HexToBlob(sqlite3VdbeDb(v), z, n); 003750 sqlite3VdbeAddOp4(v, OP_Blob, n/2, target, 0, zBlob, P4_DYNAMIC); 003751 return target; 003752 } 003753 #endif 003754 case TK_VARIABLE: { 003755 assert( !ExprHasProperty(pExpr, EP_IntValue) ); 003756 assert( pExpr->u.zToken!=0 ); 003757 assert( pExpr->u.zToken[0]!=0 ); 003758 sqlite3VdbeAddOp2(v, OP_Variable, pExpr->iColumn, target); 003759 if( pExpr->u.zToken[1]!=0 ){ 003760 const char *z = sqlite3VListNumToName(pParse->pVList, pExpr->iColumn); 003761 assert( pExpr->u.zToken[0]=='?' || (z && !strcmp(pExpr->u.zToken, z)) ); 003762 pParse->pVList[0] = 0; /* Indicate VList may no longer be enlarged */ 003763 sqlite3VdbeAppendP4(v, (char*)z, P4_STATIC); 003764 } 003765 return target; 003766 } 003767 case TK_REGISTER: { 003768 return pExpr->iTable; 003769 } 003770 #ifndef SQLITE_OMIT_CAST 003771 case TK_CAST: { 003772 /* Expressions of the form: CAST(pLeft AS token) */ 003773 inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target); 003774 if( inReg!=target ){ 003775 sqlite3VdbeAddOp2(v, OP_SCopy, inReg, target); 003776 inReg = target; 003777 } 003778 sqlite3VdbeAddOp2(v, OP_Cast, target, 003779 sqlite3AffinityType(pExpr->u.zToken, 0)); 003780 return inReg; 003781 } 003782 #endif /* SQLITE_OMIT_CAST */ 003783 case TK_IS: 003784 case TK_ISNOT: 003785 op = (op==TK_IS) ? TK_EQ : TK_NE; 003786 p5 = SQLITE_NULLEQ; 003787 /* fall-through */ 003788 case TK_LT: 003789 case TK_LE: 003790 case TK_GT: 003791 case TK_GE: 003792 case TK_NE: 003793 case TK_EQ: { 003794 Expr *pLeft = pExpr->pLeft; 003795 if( sqlite3ExprIsVector(pLeft) ){ 003796 codeVectorCompare(pParse, pExpr, target, op, p5); 003797 }else{ 003798 r1 = sqlite3ExprCodeTemp(pParse, pLeft, ®Free1); 003799 r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, ®Free2); 003800 codeCompare(pParse, pLeft, pExpr->pRight, op, 003801 r1, r2, inReg, SQLITE_STOREP2 | p5, 003802 ExprHasProperty(pExpr,EP_Commuted)); 003803 assert(TK_LT==OP_Lt); testcase(op==OP_Lt); VdbeCoverageIf(v,op==OP_Lt); 003804 assert(TK_LE==OP_Le); testcase(op==OP_Le); VdbeCoverageIf(v,op==OP_Le); 003805 assert(TK_GT==OP_Gt); testcase(op==OP_Gt); VdbeCoverageIf(v,op==OP_Gt); 003806 assert(TK_GE==OP_Ge); testcase(op==OP_Ge); VdbeCoverageIf(v,op==OP_Ge); 003807 assert(TK_EQ==OP_Eq); testcase(op==OP_Eq); VdbeCoverageIf(v,op==OP_Eq); 003808 assert(TK_NE==OP_Ne); testcase(op==OP_Ne); VdbeCoverageIf(v,op==OP_Ne); 003809 testcase( regFree1==0 ); 003810 testcase( regFree2==0 ); 003811 } 003812 break; 003813 } 003814 case TK_AND: 003815 case TK_OR: 003816 case TK_PLUS: 003817 case TK_STAR: 003818 case TK_MINUS: 003819 case TK_REM: 003820 case TK_BITAND: 003821 case TK_BITOR: 003822 case TK_SLASH: 003823 case TK_LSHIFT: 003824 case TK_RSHIFT: 003825 case TK_CONCAT: { 003826 assert( TK_AND==OP_And ); testcase( op==TK_AND ); 003827 assert( TK_OR==OP_Or ); testcase( op==TK_OR ); 003828 assert( TK_PLUS==OP_Add ); testcase( op==TK_PLUS ); 003829 assert( TK_MINUS==OP_Subtract ); testcase( op==TK_MINUS ); 003830 assert( TK_REM==OP_Remainder ); testcase( op==TK_REM ); 003831 assert( TK_BITAND==OP_BitAnd ); testcase( op==TK_BITAND ); 003832 assert( TK_BITOR==OP_BitOr ); testcase( op==TK_BITOR ); 003833 assert( TK_SLASH==OP_Divide ); testcase( op==TK_SLASH ); 003834 assert( TK_LSHIFT==OP_ShiftLeft ); testcase( op==TK_LSHIFT ); 003835 assert( TK_RSHIFT==OP_ShiftRight ); testcase( op==TK_RSHIFT ); 003836 assert( TK_CONCAT==OP_Concat ); testcase( op==TK_CONCAT ); 003837 r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1); 003838 r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, ®Free2); 003839 sqlite3VdbeAddOp3(v, op, r2, r1, target); 003840 testcase( regFree1==0 ); 003841 testcase( regFree2==0 ); 003842 break; 003843 } 003844 case TK_UMINUS: { 003845 Expr *pLeft = pExpr->pLeft; 003846 assert( pLeft ); 003847 if( pLeft->op==TK_INTEGER ){ 003848 codeInteger(pParse, pLeft, 1, target); 003849 return target; 003850 #ifndef SQLITE_OMIT_FLOATING_POINT 003851 }else if( pLeft->op==TK_FLOAT ){ 003852 assert( !ExprHasProperty(pExpr, EP_IntValue) ); 003853 codeReal(v, pLeft->u.zToken, 1, target); 003854 return target; 003855 #endif 003856 }else{ 003857 tempX.op = TK_INTEGER; 003858 tempX.flags = EP_IntValue|EP_TokenOnly; 003859 tempX.u.iValue = 0; 003860 r1 = sqlite3ExprCodeTemp(pParse, &tempX, ®Free1); 003861 r2 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free2); 003862 sqlite3VdbeAddOp3(v, OP_Subtract, r2, r1, target); 003863 testcase( regFree2==0 ); 003864 } 003865 break; 003866 } 003867 case TK_BITNOT: 003868 case TK_NOT: { 003869 assert( TK_BITNOT==OP_BitNot ); testcase( op==TK_BITNOT ); 003870 assert( TK_NOT==OP_Not ); testcase( op==TK_NOT ); 003871 r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1); 003872 testcase( regFree1==0 ); 003873 sqlite3VdbeAddOp2(v, op, r1, inReg); 003874 break; 003875 } 003876 case TK_TRUTH: { 003877 int isTrue; /* IS TRUE or IS NOT TRUE */ 003878 int bNormal; /* IS TRUE or IS FALSE */ 003879 r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1); 003880 testcase( regFree1==0 ); 003881 isTrue = sqlite3ExprTruthValue(pExpr->pRight); 003882 bNormal = pExpr->op2==TK_IS; 003883 testcase( isTrue && bNormal); 003884 testcase( !isTrue && bNormal); 003885 sqlite3VdbeAddOp4Int(v, OP_IsTrue, r1, inReg, !isTrue, isTrue ^ bNormal); 003886 break; 003887 } 003888 case TK_ISNULL: 003889 case TK_NOTNULL: { 003890 int addr; 003891 assert( TK_ISNULL==OP_IsNull ); testcase( op==TK_ISNULL ); 003892 assert( TK_NOTNULL==OP_NotNull ); testcase( op==TK_NOTNULL ); 003893 sqlite3VdbeAddOp2(v, OP_Integer, 1, target); 003894 r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1); 003895 testcase( regFree1==0 ); 003896 addr = sqlite3VdbeAddOp1(v, op, r1); 003897 VdbeCoverageIf(v, op==TK_ISNULL); 003898 VdbeCoverageIf(v, op==TK_NOTNULL); 003899 sqlite3VdbeAddOp2(v, OP_Integer, 0, target); 003900 sqlite3VdbeJumpHere(v, addr); 003901 break; 003902 } 003903 case TK_AGG_FUNCTION: { 003904 AggInfo *pInfo = pExpr->pAggInfo; 003905 if( pInfo==0 ){ 003906 assert( !ExprHasProperty(pExpr, EP_IntValue) ); 003907 sqlite3ErrorMsg(pParse, "misuse of aggregate: %s()", pExpr->u.zToken); 003908 }else{ 003909 return pInfo->aFunc[pExpr->iAgg].iMem; 003910 } 003911 break; 003912 } 003913 case TK_FUNCTION: { 003914 ExprList *pFarg; /* List of function arguments */ 003915 int nFarg; /* Number of function arguments */ 003916 FuncDef *pDef; /* The function definition object */ 003917 const char *zId; /* The function name */ 003918 u32 constMask = 0; /* Mask of function arguments that are constant */ 003919 int i; /* Loop counter */ 003920 sqlite3 *db = pParse->db; /* The database connection */ 003921 u8 enc = ENC(db); /* The text encoding used by this database */ 003922 CollSeq *pColl = 0; /* A collating sequence */ 003923 003924 #ifndef SQLITE_OMIT_WINDOWFUNC 003925 if( ExprHasProperty(pExpr, EP_WinFunc) ){ 003926 return pExpr->y.pWin->regResult; 003927 } 003928 #endif 003929 003930 if( ConstFactorOk(pParse) && sqlite3ExprIsConstantNotJoin(pExpr) ){ 003931 /* SQL functions can be expensive. So try to move constant functions 003932 ** out of the inner loop, even if that means an extra OP_Copy. */ 003933 return sqlite3ExprCodeAtInit(pParse, pExpr, -1); 003934 } 003935 assert( !ExprHasProperty(pExpr, EP_xIsSelect) ); 003936 if( ExprHasProperty(pExpr, EP_TokenOnly) ){ 003937 pFarg = 0; 003938 }else{ 003939 pFarg = pExpr->x.pList; 003940 } 003941 nFarg = pFarg ? pFarg->nExpr : 0; 003942 assert( !ExprHasProperty(pExpr, EP_IntValue) ); 003943 zId = pExpr->u.zToken; 003944 pDef = sqlite3FindFunction(db, zId, nFarg, enc, 0); 003945 #ifdef SQLITE_ENABLE_UNKNOWN_SQL_FUNCTION 003946 if( pDef==0 && pParse->explain ){ 003947 pDef = sqlite3FindFunction(db, "unknown", nFarg, enc, 0); 003948 } 003949 #endif 003950 if( pDef==0 || pDef->xFinalize!=0 ){ 003951 sqlite3ErrorMsg(pParse, "unknown function: %s()", zId); 003952 break; 003953 } 003954 003955 /* Attempt a direct implementation of the built-in COALESCE() and 003956 ** IFNULL() functions. This avoids unnecessary evaluation of 003957 ** arguments past the first non-NULL argument. 003958 */ 003959 if( pDef->funcFlags & SQLITE_FUNC_COALESCE ){ 003960 int endCoalesce = sqlite3VdbeMakeLabel(pParse); 003961 assert( nFarg>=2 ); 003962 sqlite3ExprCode(pParse, pFarg->a[0].pExpr, target); 003963 for(i=1; i<nFarg; i++){ 003964 sqlite3VdbeAddOp2(v, OP_NotNull, target, endCoalesce); 003965 VdbeCoverage(v); 003966 sqlite3ExprCode(pParse, pFarg->a[i].pExpr, target); 003967 } 003968 sqlite3VdbeResolveLabel(v, endCoalesce); 003969 break; 003970 } 003971 003972 /* The UNLIKELY() function is a no-op. The result is the value 003973 ** of the first argument. 003974 */ 003975 if( pDef->funcFlags & SQLITE_FUNC_UNLIKELY ){ 003976 assert( nFarg>=1 ); 003977 return sqlite3ExprCodeTarget(pParse, pFarg->a[0].pExpr, target); 003978 } 003979 003980 #ifdef SQLITE_DEBUG 003981 /* The AFFINITY() function evaluates to a string that describes 003982 ** the type affinity of the argument. This is used for testing of 003983 ** the SQLite type logic. 003984 */ 003985 if( pDef->funcFlags & SQLITE_FUNC_AFFINITY ){ 003986 const char *azAff[] = { "blob", "text", "numeric", "integer", "real" }; 003987 char aff; 003988 assert( nFarg==1 ); 003989 aff = sqlite3ExprAffinity(pFarg->a[0].pExpr); 003990 sqlite3VdbeLoadString(v, target, 003991 (aff<=SQLITE_AFF_NONE) ? "none" : azAff[aff-SQLITE_AFF_BLOB]); 003992 return target; 003993 } 003994 #endif 003995 003996 for(i=0; i<nFarg; i++){ 003997 if( i<32 && sqlite3ExprIsConstant(pFarg->a[i].pExpr) ){ 003998 testcase( i==31 ); 003999 constMask |= MASKBIT32(i); 004000 } 004001 if( (pDef->funcFlags & SQLITE_FUNC_NEEDCOLL)!=0 && !pColl ){ 004002 pColl = sqlite3ExprCollSeq(pParse, pFarg->a[i].pExpr); 004003 } 004004 } 004005 if( pFarg ){ 004006 if( constMask ){ 004007 r1 = pParse->nMem+1; 004008 pParse->nMem += nFarg; 004009 }else{ 004010 r1 = sqlite3GetTempRange(pParse, nFarg); 004011 } 004012 004013 /* For length() and typeof() functions with a column argument, 004014 ** set the P5 parameter to the OP_Column opcode to OPFLAG_LENGTHARG 004015 ** or OPFLAG_TYPEOFARG respectively, to avoid unnecessary data 004016 ** loading. 004017 */ 004018 if( (pDef->funcFlags & (SQLITE_FUNC_LENGTH|SQLITE_FUNC_TYPEOF))!=0 ){ 004019 u8 exprOp; 004020 assert( nFarg==1 ); 004021 assert( pFarg->a[0].pExpr!=0 ); 004022 exprOp = pFarg->a[0].pExpr->op; 004023 if( exprOp==TK_COLUMN || exprOp==TK_AGG_COLUMN ){ 004024 assert( SQLITE_FUNC_LENGTH==OPFLAG_LENGTHARG ); 004025 assert( SQLITE_FUNC_TYPEOF==OPFLAG_TYPEOFARG ); 004026 testcase( pDef->funcFlags & OPFLAG_LENGTHARG ); 004027 pFarg->a[0].pExpr->op2 = 004028 pDef->funcFlags & (OPFLAG_LENGTHARG|OPFLAG_TYPEOFARG); 004029 } 004030 } 004031 004032 sqlite3ExprCodeExprList(pParse, pFarg, r1, 0, 004033 SQLITE_ECEL_DUP|SQLITE_ECEL_FACTOR); 004034 }else{ 004035 r1 = 0; 004036 } 004037 #ifndef SQLITE_OMIT_VIRTUALTABLE 004038 /* Possibly overload the function if the first argument is 004039 ** a virtual table column. 004040 ** 004041 ** For infix functions (LIKE, GLOB, REGEXP, and MATCH) use the 004042 ** second argument, not the first, as the argument to test to 004043 ** see if it is a column in a virtual table. This is done because 004044 ** the left operand of infix functions (the operand we want to 004045 ** control overloading) ends up as the second argument to the 004046 ** function. The expression "A glob B" is equivalent to 004047 ** "glob(B,A). We want to use the A in "A glob B" to test 004048 ** for function overloading. But we use the B term in "glob(B,A)". 004049 */ 004050 if( nFarg>=2 && ExprHasProperty(pExpr, EP_InfixFunc) ){ 004051 pDef = sqlite3VtabOverloadFunction(db, pDef, nFarg, pFarg->a[1].pExpr); 004052 }else if( nFarg>0 ){ 004053 pDef = sqlite3VtabOverloadFunction(db, pDef, nFarg, pFarg->a[0].pExpr); 004054 } 004055 #endif 004056 if( pDef->funcFlags & SQLITE_FUNC_NEEDCOLL ){ 004057 if( !pColl ) pColl = db->pDfltColl; 004058 sqlite3VdbeAddOp4(v, OP_CollSeq, 0, 0, 0, (char *)pColl, P4_COLLSEQ); 004059 } 004060 #ifdef SQLITE_ENABLE_OFFSET_SQL_FUNC 004061 if( pDef->funcFlags & SQLITE_FUNC_OFFSET ){ 004062 Expr *pArg = pFarg->a[0].pExpr; 004063 if( pArg->op==TK_COLUMN ){ 004064 sqlite3VdbeAddOp3(v, OP_Offset, pArg->iTable, pArg->iColumn, target); 004065 }else{ 004066 sqlite3VdbeAddOp2(v, OP_Null, 0, target); 004067 } 004068 }else 004069 #endif 004070 { 004071 sqlite3VdbeAddFunctionCall(pParse, constMask, r1, target, nFarg, 004072 pDef, pExpr->op2); 004073 } 004074 if( nFarg ){ 004075 if( constMask==0 ){ 004076 sqlite3ReleaseTempRange(pParse, r1, nFarg); 004077 }else{ 004078 sqlite3VdbeReleaseRegisters(pParse, r1, nFarg, constMask); 004079 } 004080 } 004081 return target; 004082 } 004083 #ifndef SQLITE_OMIT_SUBQUERY 004084 case TK_EXISTS: 004085 case TK_SELECT: { 004086 int nCol; 004087 testcase( op==TK_EXISTS ); 004088 testcase( op==TK_SELECT ); 004089 if( op==TK_SELECT && (nCol = pExpr->x.pSelect->pEList->nExpr)!=1 ){ 004090 sqlite3SubselectError(pParse, nCol, 1); 004091 }else{ 004092 return sqlite3CodeSubselect(pParse, pExpr); 004093 } 004094 break; 004095 } 004096 case TK_SELECT_COLUMN: { 004097 int n; 004098 if( pExpr->pLeft->iTable==0 ){ 004099 pExpr->pLeft->iTable = sqlite3CodeSubselect(pParse, pExpr->pLeft); 004100 } 004101 assert( pExpr->iTable==0 || pExpr->pLeft->op==TK_SELECT ); 004102 if( pExpr->iTable!=0 004103 && pExpr->iTable!=(n = sqlite3ExprVectorSize(pExpr->pLeft)) 004104 ){ 004105 sqlite3ErrorMsg(pParse, "%d columns assigned %d values", 004106 pExpr->iTable, n); 004107 } 004108 return pExpr->pLeft->iTable + pExpr->iColumn; 004109 } 004110 case TK_IN: { 004111 int destIfFalse = sqlite3VdbeMakeLabel(pParse); 004112 int destIfNull = sqlite3VdbeMakeLabel(pParse); 004113 sqlite3VdbeAddOp2(v, OP_Null, 0, target); 004114 sqlite3ExprCodeIN(pParse, pExpr, destIfFalse, destIfNull); 004115 sqlite3VdbeAddOp2(v, OP_Integer, 1, target); 004116 sqlite3VdbeResolveLabel(v, destIfFalse); 004117 sqlite3VdbeAddOp2(v, OP_AddImm, target, 0); 004118 sqlite3VdbeResolveLabel(v, destIfNull); 004119 return target; 004120 } 004121 #endif /* SQLITE_OMIT_SUBQUERY */ 004122 004123 004124 /* 004125 ** x BETWEEN y AND z 004126 ** 004127 ** This is equivalent to 004128 ** 004129 ** x>=y AND x<=z 004130 ** 004131 ** X is stored in pExpr->pLeft. 004132 ** Y is stored in pExpr->pList->a[0].pExpr. 004133 ** Z is stored in pExpr->pList->a[1].pExpr. 004134 */ 004135 case TK_BETWEEN: { 004136 exprCodeBetween(pParse, pExpr, target, 0, 0); 004137 return target; 004138 } 004139 case TK_SPAN: 004140 case TK_COLLATE: 004141 case TK_UPLUS: { 004142 pExpr = pExpr->pLeft; 004143 goto expr_code_doover; /* 2018-04-28: Prevent deep recursion. OSSFuzz. */ 004144 } 004145 004146 case TK_TRIGGER: { 004147 /* If the opcode is TK_TRIGGER, then the expression is a reference 004148 ** to a column in the new.* or old.* pseudo-tables available to 004149 ** trigger programs. In this case Expr.iTable is set to 1 for the 004150 ** new.* pseudo-table, or 0 for the old.* pseudo-table. Expr.iColumn 004151 ** is set to the column of the pseudo-table to read, or to -1 to 004152 ** read the rowid field. 004153 ** 004154 ** The expression is implemented using an OP_Param opcode. The p1 004155 ** parameter is set to 0 for an old.rowid reference, or to (i+1) 004156 ** to reference another column of the old.* pseudo-table, where 004157 ** i is the index of the column. For a new.rowid reference, p1 is 004158 ** set to (n+1), where n is the number of columns in each pseudo-table. 004159 ** For a reference to any other column in the new.* pseudo-table, p1 004160 ** is set to (n+2+i), where n and i are as defined previously. For 004161 ** example, if the table on which triggers are being fired is 004162 ** declared as: 004163 ** 004164 ** CREATE TABLE t1(a, b); 004165 ** 004166 ** Then p1 is interpreted as follows: 004167 ** 004168 ** p1==0 -> old.rowid p1==3 -> new.rowid 004169 ** p1==1 -> old.a p1==4 -> new.a 004170 ** p1==2 -> old.b p1==5 -> new.b 004171 */ 004172 Table *pTab = pExpr->y.pTab; 004173 int iCol = pExpr->iColumn; 004174 int p1 = pExpr->iTable * (pTab->nCol+1) + 1 004175 + sqlite3TableColumnToStorage(pTab, iCol); 004176 004177 assert( pExpr->iTable==0 || pExpr->iTable==1 ); 004178 assert( iCol>=-1 && iCol<pTab->nCol ); 004179 assert( pTab->iPKey<0 || iCol!=pTab->iPKey ); 004180 assert( p1>=0 && p1<(pTab->nCol*2+2) ); 004181 004182 sqlite3VdbeAddOp2(v, OP_Param, p1, target); 004183 VdbeComment((v, "r[%d]=%s.%s", target, 004184 (pExpr->iTable ? "new" : "old"), 004185 (pExpr->iColumn<0 ? "rowid" : pExpr->y.pTab->aCol[iCol].zName) 004186 )); 004187 004188 #ifndef SQLITE_OMIT_FLOATING_POINT 004189 /* If the column has REAL affinity, it may currently be stored as an 004190 ** integer. Use OP_RealAffinity to make sure it is really real. 004191 ** 004192 ** EVIDENCE-OF: R-60985-57662 SQLite will convert the value back to 004193 ** floating point when extracting it from the record. */ 004194 if( iCol>=0 && pTab->aCol[iCol].affinity==SQLITE_AFF_REAL ){ 004195 sqlite3VdbeAddOp1(v, OP_RealAffinity, target); 004196 } 004197 #endif 004198 break; 004199 } 004200 004201 case TK_VECTOR: { 004202 sqlite3ErrorMsg(pParse, "row value misused"); 004203 break; 004204 } 004205 004206 /* TK_IF_NULL_ROW Expr nodes are inserted ahead of expressions 004207 ** that derive from the right-hand table of a LEFT JOIN. The 004208 ** Expr.iTable value is the table number for the right-hand table. 004209 ** The expression is only evaluated if that table is not currently 004210 ** on a LEFT JOIN NULL row. 004211 */ 004212 case TK_IF_NULL_ROW: { 004213 int addrINR; 004214 u8 okConstFactor = pParse->okConstFactor; 004215 addrINR = sqlite3VdbeAddOp1(v, OP_IfNullRow, pExpr->iTable); 004216 /* Temporarily disable factoring of constant expressions, since 004217 ** even though expressions may appear to be constant, they are not 004218 ** really constant because they originate from the right-hand side 004219 ** of a LEFT JOIN. */ 004220 pParse->okConstFactor = 0; 004221 inReg = sqlite3ExprCodeTarget(pParse, pExpr->pLeft, target); 004222 pParse->okConstFactor = okConstFactor; 004223 sqlite3VdbeJumpHere(v, addrINR); 004224 sqlite3VdbeChangeP3(v, addrINR, inReg); 004225 break; 004226 } 004227 004228 /* 004229 ** Form A: 004230 ** CASE x WHEN e1 THEN r1 WHEN e2 THEN r2 ... WHEN eN THEN rN ELSE y END 004231 ** 004232 ** Form B: 004233 ** CASE WHEN e1 THEN r1 WHEN e2 THEN r2 ... WHEN eN THEN rN ELSE y END 004234 ** 004235 ** Form A is can be transformed into the equivalent form B as follows: 004236 ** CASE WHEN x=e1 THEN r1 WHEN x=e2 THEN r2 ... 004237 ** WHEN x=eN THEN rN ELSE y END 004238 ** 004239 ** X (if it exists) is in pExpr->pLeft. 004240 ** Y is in the last element of pExpr->x.pList if pExpr->x.pList->nExpr is 004241 ** odd. The Y is also optional. If the number of elements in x.pList 004242 ** is even, then Y is omitted and the "otherwise" result is NULL. 004243 ** Ei is in pExpr->pList->a[i*2] and Ri is pExpr->pList->a[i*2+1]. 004244 ** 004245 ** The result of the expression is the Ri for the first matching Ei, 004246 ** or if there is no matching Ei, the ELSE term Y, or if there is 004247 ** no ELSE term, NULL. 004248 */ 004249 case TK_CASE: { 004250 int endLabel; /* GOTO label for end of CASE stmt */ 004251 int nextCase; /* GOTO label for next WHEN clause */ 004252 int nExpr; /* 2x number of WHEN terms */ 004253 int i; /* Loop counter */ 004254 ExprList *pEList; /* List of WHEN terms */ 004255 struct ExprList_item *aListelem; /* Array of WHEN terms */ 004256 Expr opCompare; /* The X==Ei expression */ 004257 Expr *pX; /* The X expression */ 004258 Expr *pTest = 0; /* X==Ei (form A) or just Ei (form B) */ 004259 Expr *pDel = 0; 004260 sqlite3 *db = pParse->db; 004261 004262 assert( !ExprHasProperty(pExpr, EP_xIsSelect) && pExpr->x.pList ); 004263 assert(pExpr->x.pList->nExpr > 0); 004264 pEList = pExpr->x.pList; 004265 aListelem = pEList->a; 004266 nExpr = pEList->nExpr; 004267 endLabel = sqlite3VdbeMakeLabel(pParse); 004268 if( (pX = pExpr->pLeft)!=0 ){ 004269 pDel = sqlite3ExprDup(db, pX, 0); 004270 if( db->mallocFailed ){ 004271 sqlite3ExprDelete(db, pDel); 004272 break; 004273 } 004274 testcase( pX->op==TK_COLUMN ); 004275 exprToRegister(pDel, exprCodeVector(pParse, pDel, ®Free1)); 004276 testcase( regFree1==0 ); 004277 memset(&opCompare, 0, sizeof(opCompare)); 004278 opCompare.op = TK_EQ; 004279 opCompare.pLeft = pDel; 004280 pTest = &opCompare; 004281 /* Ticket b351d95f9cd5ef17e9d9dbae18f5ca8611190001: 004282 ** The value in regFree1 might get SCopy-ed into the file result. 004283 ** So make sure that the regFree1 register is not reused for other 004284 ** purposes and possibly overwritten. */ 004285 regFree1 = 0; 004286 } 004287 for(i=0; i<nExpr-1; i=i+2){ 004288 if( pX ){ 004289 assert( pTest!=0 ); 004290 opCompare.pRight = aListelem[i].pExpr; 004291 }else{ 004292 pTest = aListelem[i].pExpr; 004293 } 004294 nextCase = sqlite3VdbeMakeLabel(pParse); 004295 testcase( pTest->op==TK_COLUMN ); 004296 sqlite3ExprIfFalse(pParse, pTest, nextCase, SQLITE_JUMPIFNULL); 004297 testcase( aListelem[i+1].pExpr->op==TK_COLUMN ); 004298 sqlite3ExprCode(pParse, aListelem[i+1].pExpr, target); 004299 sqlite3VdbeGoto(v, endLabel); 004300 sqlite3VdbeResolveLabel(v, nextCase); 004301 } 004302 if( (nExpr&1)!=0 ){ 004303 sqlite3ExprCode(pParse, pEList->a[nExpr-1].pExpr, target); 004304 }else{ 004305 sqlite3VdbeAddOp2(v, OP_Null, 0, target); 004306 } 004307 sqlite3ExprDelete(db, pDel); 004308 sqlite3VdbeResolveLabel(v, endLabel); 004309 break; 004310 } 004311 #ifndef SQLITE_OMIT_TRIGGER 004312 case TK_RAISE: { 004313 assert( pExpr->affExpr==OE_Rollback 004314 || pExpr->affExpr==OE_Abort 004315 || pExpr->affExpr==OE_Fail 004316 || pExpr->affExpr==OE_Ignore 004317 ); 004318 if( !pParse->pTriggerTab ){ 004319 sqlite3ErrorMsg(pParse, 004320 "RAISE() may only be used within a trigger-program"); 004321 return 0; 004322 } 004323 if( pExpr->affExpr==OE_Abort ){ 004324 sqlite3MayAbort(pParse); 004325 } 004326 assert( !ExprHasProperty(pExpr, EP_IntValue) ); 004327 if( pExpr->affExpr==OE_Ignore ){ 004328 sqlite3VdbeAddOp4( 004329 v, OP_Halt, SQLITE_OK, OE_Ignore, 0, pExpr->u.zToken,0); 004330 VdbeCoverage(v); 004331 }else{ 004332 sqlite3HaltConstraint(pParse, SQLITE_CONSTRAINT_TRIGGER, 004333 pExpr->affExpr, pExpr->u.zToken, 0, 0); 004334 } 004335 004336 break; 004337 } 004338 #endif 004339 } 004340 sqlite3ReleaseTempReg(pParse, regFree1); 004341 sqlite3ReleaseTempReg(pParse, regFree2); 004342 return inReg; 004343 } 004344 004345 /* 004346 ** Factor out the code of the given expression to initialization time. 004347 ** 004348 ** If regDest>=0 then the result is always stored in that register and the 004349 ** result is not reusable. If regDest<0 then this routine is free to 004350 ** store the value whereever it wants. The register where the expression 004351 ** is stored is returned. When regDest<0, two identical expressions will 004352 ** code to the same register. 004353 */ 004354 int sqlite3ExprCodeAtInit( 004355 Parse *pParse, /* Parsing context */ 004356 Expr *pExpr, /* The expression to code when the VDBE initializes */ 004357 int regDest /* Store the value in this register */ 004358 ){ 004359 ExprList *p; 004360 assert( ConstFactorOk(pParse) ); 004361 p = pParse->pConstExpr; 004362 if( regDest<0 && p ){ 004363 struct ExprList_item *pItem; 004364 int i; 004365 for(pItem=p->a, i=p->nExpr; i>0; pItem++, i--){ 004366 if( pItem->reusable && sqlite3ExprCompare(0,pItem->pExpr,pExpr,-1)==0 ){ 004367 return pItem->u.iConstExprReg; 004368 } 004369 } 004370 } 004371 pExpr = sqlite3ExprDup(pParse->db, pExpr, 0); 004372 p = sqlite3ExprListAppend(pParse, p, pExpr); 004373 if( p ){ 004374 struct ExprList_item *pItem = &p->a[p->nExpr-1]; 004375 pItem->reusable = regDest<0; 004376 if( regDest<0 ) regDest = ++pParse->nMem; 004377 pItem->u.iConstExprReg = regDest; 004378 } 004379 pParse->pConstExpr = p; 004380 return regDest; 004381 } 004382 004383 /* 004384 ** Generate code to evaluate an expression and store the results 004385 ** into a register. Return the register number where the results 004386 ** are stored. 004387 ** 004388 ** If the register is a temporary register that can be deallocated, 004389 ** then write its number into *pReg. If the result register is not 004390 ** a temporary, then set *pReg to zero. 004391 ** 004392 ** If pExpr is a constant, then this routine might generate this 004393 ** code to fill the register in the initialization section of the 004394 ** VDBE program, in order to factor it out of the evaluation loop. 004395 */ 004396 int sqlite3ExprCodeTemp(Parse *pParse, Expr *pExpr, int *pReg){ 004397 int r2; 004398 pExpr = sqlite3ExprSkipCollateAndLikely(pExpr); 004399 if( ConstFactorOk(pParse) 004400 && pExpr->op!=TK_REGISTER 004401 && sqlite3ExprIsConstantNotJoin(pExpr) 004402 ){ 004403 *pReg = 0; 004404 r2 = sqlite3ExprCodeAtInit(pParse, pExpr, -1); 004405 }else{ 004406 int r1 = sqlite3GetTempReg(pParse); 004407 r2 = sqlite3ExprCodeTarget(pParse, pExpr, r1); 004408 if( r2==r1 ){ 004409 *pReg = r1; 004410 }else{ 004411 sqlite3ReleaseTempReg(pParse, r1); 004412 *pReg = 0; 004413 } 004414 } 004415 return r2; 004416 } 004417 004418 /* 004419 ** Generate code that will evaluate expression pExpr and store the 004420 ** results in register target. The results are guaranteed to appear 004421 ** in register target. 004422 */ 004423 void sqlite3ExprCode(Parse *pParse, Expr *pExpr, int target){ 004424 int inReg; 004425 004426 assert( target>0 && target<=pParse->nMem ); 004427 inReg = sqlite3ExprCodeTarget(pParse, pExpr, target); 004428 assert( pParse->pVdbe!=0 || pParse->db->mallocFailed ); 004429 if( inReg!=target && pParse->pVdbe ){ 004430 sqlite3VdbeAddOp2(pParse->pVdbe, OP_SCopy, inReg, target); 004431 } 004432 } 004433 004434 /* 004435 ** Make a transient copy of expression pExpr and then code it using 004436 ** sqlite3ExprCode(). This routine works just like sqlite3ExprCode() 004437 ** except that the input expression is guaranteed to be unchanged. 004438 */ 004439 void sqlite3ExprCodeCopy(Parse *pParse, Expr *pExpr, int target){ 004440 sqlite3 *db = pParse->db; 004441 pExpr = sqlite3ExprDup(db, pExpr, 0); 004442 if( !db->mallocFailed ) sqlite3ExprCode(pParse, pExpr, target); 004443 sqlite3ExprDelete(db, pExpr); 004444 } 004445 004446 /* 004447 ** Generate code that will evaluate expression pExpr and store the 004448 ** results in register target. The results are guaranteed to appear 004449 ** in register target. If the expression is constant, then this routine 004450 ** might choose to code the expression at initialization time. 004451 */ 004452 void sqlite3ExprCodeFactorable(Parse *pParse, Expr *pExpr, int target){ 004453 if( pParse->okConstFactor && sqlite3ExprIsConstantNotJoin(pExpr) ){ 004454 sqlite3ExprCodeAtInit(pParse, pExpr, target); 004455 }else{ 004456 sqlite3ExprCode(pParse, pExpr, target); 004457 } 004458 } 004459 004460 /* 004461 ** Generate code that pushes the value of every element of the given 004462 ** expression list into a sequence of registers beginning at target. 004463 ** 004464 ** Return the number of elements evaluated. The number returned will 004465 ** usually be pList->nExpr but might be reduced if SQLITE_ECEL_OMITREF 004466 ** is defined. 004467 ** 004468 ** The SQLITE_ECEL_DUP flag prevents the arguments from being 004469 ** filled using OP_SCopy. OP_Copy must be used instead. 004470 ** 004471 ** The SQLITE_ECEL_FACTOR argument allows constant arguments to be 004472 ** factored out into initialization code. 004473 ** 004474 ** The SQLITE_ECEL_REF flag means that expressions in the list with 004475 ** ExprList.a[].u.x.iOrderByCol>0 have already been evaluated and stored 004476 ** in registers at srcReg, and so the value can be copied from there. 004477 ** If SQLITE_ECEL_OMITREF is also set, then the values with u.x.iOrderByCol>0 004478 ** are simply omitted rather than being copied from srcReg. 004479 */ 004480 int sqlite3ExprCodeExprList( 004481 Parse *pParse, /* Parsing context */ 004482 ExprList *pList, /* The expression list to be coded */ 004483 int target, /* Where to write results */ 004484 int srcReg, /* Source registers if SQLITE_ECEL_REF */ 004485 u8 flags /* SQLITE_ECEL_* flags */ 004486 ){ 004487 struct ExprList_item *pItem; 004488 int i, j, n; 004489 u8 copyOp = (flags & SQLITE_ECEL_DUP) ? OP_Copy : OP_SCopy; 004490 Vdbe *v = pParse->pVdbe; 004491 assert( pList!=0 ); 004492 assert( target>0 ); 004493 assert( pParse->pVdbe!=0 ); /* Never gets this far otherwise */ 004494 n = pList->nExpr; 004495 if( !ConstFactorOk(pParse) ) flags &= ~SQLITE_ECEL_FACTOR; 004496 for(pItem=pList->a, i=0; i<n; i++, pItem++){ 004497 Expr *pExpr = pItem->pExpr; 004498 #ifdef SQLITE_ENABLE_SORTER_REFERENCES 004499 if( pItem->bSorterRef ){ 004500 i--; 004501 n--; 004502 }else 004503 #endif 004504 if( (flags & SQLITE_ECEL_REF)!=0 && (j = pItem->u.x.iOrderByCol)>0 ){ 004505 if( flags & SQLITE_ECEL_OMITREF ){ 004506 i--; 004507 n--; 004508 }else{ 004509 sqlite3VdbeAddOp2(v, copyOp, j+srcReg-1, target+i); 004510 } 004511 }else if( (flags & SQLITE_ECEL_FACTOR)!=0 004512 && sqlite3ExprIsConstantNotJoin(pExpr) 004513 ){ 004514 sqlite3ExprCodeAtInit(pParse, pExpr, target+i); 004515 }else{ 004516 int inReg = sqlite3ExprCodeTarget(pParse, pExpr, target+i); 004517 if( inReg!=target+i ){ 004518 VdbeOp *pOp; 004519 if( copyOp==OP_Copy 004520 && (pOp=sqlite3VdbeGetOp(v, -1))->opcode==OP_Copy 004521 && pOp->p1+pOp->p3+1==inReg 004522 && pOp->p2+pOp->p3+1==target+i 004523 ){ 004524 pOp->p3++; 004525 }else{ 004526 sqlite3VdbeAddOp2(v, copyOp, inReg, target+i); 004527 } 004528 } 004529 } 004530 } 004531 return n; 004532 } 004533 004534 /* 004535 ** Generate code for a BETWEEN operator. 004536 ** 004537 ** x BETWEEN y AND z 004538 ** 004539 ** The above is equivalent to 004540 ** 004541 ** x>=y AND x<=z 004542 ** 004543 ** Code it as such, taking care to do the common subexpression 004544 ** elimination of x. 004545 ** 004546 ** The xJumpIf parameter determines details: 004547 ** 004548 ** NULL: Store the boolean result in reg[dest] 004549 ** sqlite3ExprIfTrue: Jump to dest if true 004550 ** sqlite3ExprIfFalse: Jump to dest if false 004551 ** 004552 ** The jumpIfNull parameter is ignored if xJumpIf is NULL. 004553 */ 004554 static void exprCodeBetween( 004555 Parse *pParse, /* Parsing and code generating context */ 004556 Expr *pExpr, /* The BETWEEN expression */ 004557 int dest, /* Jump destination or storage location */ 004558 void (*xJump)(Parse*,Expr*,int,int), /* Action to take */ 004559 int jumpIfNull /* Take the jump if the BETWEEN is NULL */ 004560 ){ 004561 Expr exprAnd; /* The AND operator in x>=y AND x<=z */ 004562 Expr compLeft; /* The x>=y term */ 004563 Expr compRight; /* The x<=z term */ 004564 int regFree1 = 0; /* Temporary use register */ 004565 Expr *pDel = 0; 004566 sqlite3 *db = pParse->db; 004567 004568 memset(&compLeft, 0, sizeof(Expr)); 004569 memset(&compRight, 0, sizeof(Expr)); 004570 memset(&exprAnd, 0, sizeof(Expr)); 004571 004572 assert( !ExprHasProperty(pExpr, EP_xIsSelect) ); 004573 pDel = sqlite3ExprDup(db, pExpr->pLeft, 0); 004574 if( db->mallocFailed==0 ){ 004575 exprAnd.op = TK_AND; 004576 exprAnd.pLeft = &compLeft; 004577 exprAnd.pRight = &compRight; 004578 compLeft.op = TK_GE; 004579 compLeft.pLeft = pDel; 004580 compLeft.pRight = pExpr->x.pList->a[0].pExpr; 004581 compRight.op = TK_LE; 004582 compRight.pLeft = pDel; 004583 compRight.pRight = pExpr->x.pList->a[1].pExpr; 004584 exprToRegister(pDel, exprCodeVector(pParse, pDel, ®Free1)); 004585 if( xJump ){ 004586 xJump(pParse, &exprAnd, dest, jumpIfNull); 004587 }else{ 004588 /* Mark the expression is being from the ON or USING clause of a join 004589 ** so that the sqlite3ExprCodeTarget() routine will not attempt to move 004590 ** it into the Parse.pConstExpr list. We should use a new bit for this, 004591 ** for clarity, but we are out of bits in the Expr.flags field so we 004592 ** have to reuse the EP_FromJoin bit. Bummer. */ 004593 pDel->flags |= EP_FromJoin; 004594 sqlite3ExprCodeTarget(pParse, &exprAnd, dest); 004595 } 004596 sqlite3ReleaseTempReg(pParse, regFree1); 004597 } 004598 sqlite3ExprDelete(db, pDel); 004599 004600 /* Ensure adequate test coverage */ 004601 testcase( xJump==sqlite3ExprIfTrue && jumpIfNull==0 && regFree1==0 ); 004602 testcase( xJump==sqlite3ExprIfTrue && jumpIfNull==0 && regFree1!=0 ); 004603 testcase( xJump==sqlite3ExprIfTrue && jumpIfNull!=0 && regFree1==0 ); 004604 testcase( xJump==sqlite3ExprIfTrue && jumpIfNull!=0 && regFree1!=0 ); 004605 testcase( xJump==sqlite3ExprIfFalse && jumpIfNull==0 && regFree1==0 ); 004606 testcase( xJump==sqlite3ExprIfFalse && jumpIfNull==0 && regFree1!=0 ); 004607 testcase( xJump==sqlite3ExprIfFalse && jumpIfNull!=0 && regFree1==0 ); 004608 testcase( xJump==sqlite3ExprIfFalse && jumpIfNull!=0 && regFree1!=0 ); 004609 testcase( xJump==0 ); 004610 } 004611 004612 /* 004613 ** Generate code for a boolean expression such that a jump is made 004614 ** to the label "dest" if the expression is true but execution 004615 ** continues straight thru if the expression is false. 004616 ** 004617 ** If the expression evaluates to NULL (neither true nor false), then 004618 ** take the jump if the jumpIfNull flag is SQLITE_JUMPIFNULL. 004619 ** 004620 ** This code depends on the fact that certain token values (ex: TK_EQ) 004621 ** are the same as opcode values (ex: OP_Eq) that implement the corresponding 004622 ** operation. Special comments in vdbe.c and the mkopcodeh.awk script in 004623 ** the make process cause these values to align. Assert()s in the code 004624 ** below verify that the numbers are aligned correctly. 004625 */ 004626 void sqlite3ExprIfTrue(Parse *pParse, Expr *pExpr, int dest, int jumpIfNull){ 004627 Vdbe *v = pParse->pVdbe; 004628 int op = 0; 004629 int regFree1 = 0; 004630 int regFree2 = 0; 004631 int r1, r2; 004632 004633 assert( jumpIfNull==SQLITE_JUMPIFNULL || jumpIfNull==0 ); 004634 if( NEVER(v==0) ) return; /* Existence of VDBE checked by caller */ 004635 if( NEVER(pExpr==0) ) return; /* No way this can happen */ 004636 op = pExpr->op; 004637 switch( op ){ 004638 case TK_AND: 004639 case TK_OR: { 004640 Expr *pAlt = sqlite3ExprSimplifiedAndOr(pExpr); 004641 if( pAlt!=pExpr ){ 004642 sqlite3ExprIfTrue(pParse, pAlt, dest, jumpIfNull); 004643 }else if( op==TK_AND ){ 004644 int d2 = sqlite3VdbeMakeLabel(pParse); 004645 testcase( jumpIfNull==0 ); 004646 sqlite3ExprIfFalse(pParse, pExpr->pLeft, d2, 004647 jumpIfNull^SQLITE_JUMPIFNULL); 004648 sqlite3ExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull); 004649 sqlite3VdbeResolveLabel(v, d2); 004650 }else{ 004651 testcase( jumpIfNull==0 ); 004652 sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, jumpIfNull); 004653 sqlite3ExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull); 004654 } 004655 break; 004656 } 004657 case TK_NOT: { 004658 testcase( jumpIfNull==0 ); 004659 sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, jumpIfNull); 004660 break; 004661 } 004662 case TK_TRUTH: { 004663 int isNot; /* IS NOT TRUE or IS NOT FALSE */ 004664 int isTrue; /* IS TRUE or IS NOT TRUE */ 004665 testcase( jumpIfNull==0 ); 004666 isNot = pExpr->op2==TK_ISNOT; 004667 isTrue = sqlite3ExprTruthValue(pExpr->pRight); 004668 testcase( isTrue && isNot ); 004669 testcase( !isTrue && isNot ); 004670 if( isTrue ^ isNot ){ 004671 sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, 004672 isNot ? SQLITE_JUMPIFNULL : 0); 004673 }else{ 004674 sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, 004675 isNot ? SQLITE_JUMPIFNULL : 0); 004676 } 004677 break; 004678 } 004679 case TK_IS: 004680 case TK_ISNOT: 004681 testcase( op==TK_IS ); 004682 testcase( op==TK_ISNOT ); 004683 op = (op==TK_IS) ? TK_EQ : TK_NE; 004684 jumpIfNull = SQLITE_NULLEQ; 004685 /* Fall thru */ 004686 case TK_LT: 004687 case TK_LE: 004688 case TK_GT: 004689 case TK_GE: 004690 case TK_NE: 004691 case TK_EQ: { 004692 if( sqlite3ExprIsVector(pExpr->pLeft) ) goto default_expr; 004693 testcase( jumpIfNull==0 ); 004694 r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1); 004695 r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, ®Free2); 004696 codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op, 004697 r1, r2, dest, jumpIfNull, ExprHasProperty(pExpr,EP_Commuted)); 004698 assert(TK_LT==OP_Lt); testcase(op==OP_Lt); VdbeCoverageIf(v,op==OP_Lt); 004699 assert(TK_LE==OP_Le); testcase(op==OP_Le); VdbeCoverageIf(v,op==OP_Le); 004700 assert(TK_GT==OP_Gt); testcase(op==OP_Gt); VdbeCoverageIf(v,op==OP_Gt); 004701 assert(TK_GE==OP_Ge); testcase(op==OP_Ge); VdbeCoverageIf(v,op==OP_Ge); 004702 assert(TK_EQ==OP_Eq); testcase(op==OP_Eq); 004703 VdbeCoverageIf(v, op==OP_Eq && jumpIfNull==SQLITE_NULLEQ); 004704 VdbeCoverageIf(v, op==OP_Eq && jumpIfNull!=SQLITE_NULLEQ); 004705 assert(TK_NE==OP_Ne); testcase(op==OP_Ne); 004706 VdbeCoverageIf(v, op==OP_Ne && jumpIfNull==SQLITE_NULLEQ); 004707 VdbeCoverageIf(v, op==OP_Ne && jumpIfNull!=SQLITE_NULLEQ); 004708 testcase( regFree1==0 ); 004709 testcase( regFree2==0 ); 004710 break; 004711 } 004712 case TK_ISNULL: 004713 case TK_NOTNULL: { 004714 assert( TK_ISNULL==OP_IsNull ); testcase( op==TK_ISNULL ); 004715 assert( TK_NOTNULL==OP_NotNull ); testcase( op==TK_NOTNULL ); 004716 r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1); 004717 sqlite3VdbeAddOp2(v, op, r1, dest); 004718 VdbeCoverageIf(v, op==TK_ISNULL); 004719 VdbeCoverageIf(v, op==TK_NOTNULL); 004720 testcase( regFree1==0 ); 004721 break; 004722 } 004723 case TK_BETWEEN: { 004724 testcase( jumpIfNull==0 ); 004725 exprCodeBetween(pParse, pExpr, dest, sqlite3ExprIfTrue, jumpIfNull); 004726 break; 004727 } 004728 #ifndef SQLITE_OMIT_SUBQUERY 004729 case TK_IN: { 004730 int destIfFalse = sqlite3VdbeMakeLabel(pParse); 004731 int destIfNull = jumpIfNull ? dest : destIfFalse; 004732 sqlite3ExprCodeIN(pParse, pExpr, destIfFalse, destIfNull); 004733 sqlite3VdbeGoto(v, dest); 004734 sqlite3VdbeResolveLabel(v, destIfFalse); 004735 break; 004736 } 004737 #endif 004738 default: { 004739 default_expr: 004740 if( ExprAlwaysTrue(pExpr) ){ 004741 sqlite3VdbeGoto(v, dest); 004742 }else if( ExprAlwaysFalse(pExpr) ){ 004743 /* No-op */ 004744 }else{ 004745 r1 = sqlite3ExprCodeTemp(pParse, pExpr, ®Free1); 004746 sqlite3VdbeAddOp3(v, OP_If, r1, dest, jumpIfNull!=0); 004747 VdbeCoverage(v); 004748 testcase( regFree1==0 ); 004749 testcase( jumpIfNull==0 ); 004750 } 004751 break; 004752 } 004753 } 004754 sqlite3ReleaseTempReg(pParse, regFree1); 004755 sqlite3ReleaseTempReg(pParse, regFree2); 004756 } 004757 004758 /* 004759 ** Generate code for a boolean expression such that a jump is made 004760 ** to the label "dest" if the expression is false but execution 004761 ** continues straight thru if the expression is true. 004762 ** 004763 ** If the expression evaluates to NULL (neither true nor false) then 004764 ** jump if jumpIfNull is SQLITE_JUMPIFNULL or fall through if jumpIfNull 004765 ** is 0. 004766 */ 004767 void sqlite3ExprIfFalse(Parse *pParse, Expr *pExpr, int dest, int jumpIfNull){ 004768 Vdbe *v = pParse->pVdbe; 004769 int op = 0; 004770 int regFree1 = 0; 004771 int regFree2 = 0; 004772 int r1, r2; 004773 004774 assert( jumpIfNull==SQLITE_JUMPIFNULL || jumpIfNull==0 ); 004775 if( NEVER(v==0) ) return; /* Existence of VDBE checked by caller */ 004776 if( pExpr==0 ) return; 004777 004778 /* The value of pExpr->op and op are related as follows: 004779 ** 004780 ** pExpr->op op 004781 ** --------- ---------- 004782 ** TK_ISNULL OP_NotNull 004783 ** TK_NOTNULL OP_IsNull 004784 ** TK_NE OP_Eq 004785 ** TK_EQ OP_Ne 004786 ** TK_GT OP_Le 004787 ** TK_LE OP_Gt 004788 ** TK_GE OP_Lt 004789 ** TK_LT OP_Ge 004790 ** 004791 ** For other values of pExpr->op, op is undefined and unused. 004792 ** The value of TK_ and OP_ constants are arranged such that we 004793 ** can compute the mapping above using the following expression. 004794 ** Assert()s verify that the computation is correct. 004795 */ 004796 op = ((pExpr->op+(TK_ISNULL&1))^1)-(TK_ISNULL&1); 004797 004798 /* Verify correct alignment of TK_ and OP_ constants 004799 */ 004800 assert( pExpr->op!=TK_ISNULL || op==OP_NotNull ); 004801 assert( pExpr->op!=TK_NOTNULL || op==OP_IsNull ); 004802 assert( pExpr->op!=TK_NE || op==OP_Eq ); 004803 assert( pExpr->op!=TK_EQ || op==OP_Ne ); 004804 assert( pExpr->op!=TK_LT || op==OP_Ge ); 004805 assert( pExpr->op!=TK_LE || op==OP_Gt ); 004806 assert( pExpr->op!=TK_GT || op==OP_Le ); 004807 assert( pExpr->op!=TK_GE || op==OP_Lt ); 004808 004809 switch( pExpr->op ){ 004810 case TK_AND: 004811 case TK_OR: { 004812 Expr *pAlt = sqlite3ExprSimplifiedAndOr(pExpr); 004813 if( pAlt!=pExpr ){ 004814 sqlite3ExprIfFalse(pParse, pAlt, dest, jumpIfNull); 004815 }else if( pExpr->op==TK_AND ){ 004816 testcase( jumpIfNull==0 ); 004817 sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, jumpIfNull); 004818 sqlite3ExprIfFalse(pParse, pExpr->pRight, dest, jumpIfNull); 004819 }else{ 004820 int d2 = sqlite3VdbeMakeLabel(pParse); 004821 testcase( jumpIfNull==0 ); 004822 sqlite3ExprIfTrue(pParse, pExpr->pLeft, d2, 004823 jumpIfNull^SQLITE_JUMPIFNULL); 004824 sqlite3ExprIfFalse(pParse, pExpr->pRight, dest, jumpIfNull); 004825 sqlite3VdbeResolveLabel(v, d2); 004826 } 004827 break; 004828 } 004829 case TK_NOT: { 004830 testcase( jumpIfNull==0 ); 004831 sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, jumpIfNull); 004832 break; 004833 } 004834 case TK_TRUTH: { 004835 int isNot; /* IS NOT TRUE or IS NOT FALSE */ 004836 int isTrue; /* IS TRUE or IS NOT TRUE */ 004837 testcase( jumpIfNull==0 ); 004838 isNot = pExpr->op2==TK_ISNOT; 004839 isTrue = sqlite3ExprTruthValue(pExpr->pRight); 004840 testcase( isTrue && isNot ); 004841 testcase( !isTrue && isNot ); 004842 if( isTrue ^ isNot ){ 004843 /* IS TRUE and IS NOT FALSE */ 004844 sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, 004845 isNot ? 0 : SQLITE_JUMPIFNULL); 004846 004847 }else{ 004848 /* IS FALSE and IS NOT TRUE */ 004849 sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, 004850 isNot ? 0 : SQLITE_JUMPIFNULL); 004851 } 004852 break; 004853 } 004854 case TK_IS: 004855 case TK_ISNOT: 004856 testcase( pExpr->op==TK_IS ); 004857 testcase( pExpr->op==TK_ISNOT ); 004858 op = (pExpr->op==TK_IS) ? TK_NE : TK_EQ; 004859 jumpIfNull = SQLITE_NULLEQ; 004860 /* Fall thru */ 004861 case TK_LT: 004862 case TK_LE: 004863 case TK_GT: 004864 case TK_GE: 004865 case TK_NE: 004866 case TK_EQ: { 004867 if( sqlite3ExprIsVector(pExpr->pLeft) ) goto default_expr; 004868 testcase( jumpIfNull==0 ); 004869 r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1); 004870 r2 = sqlite3ExprCodeTemp(pParse, pExpr->pRight, ®Free2); 004871 codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op, 004872 r1, r2, dest, jumpIfNull,ExprHasProperty(pExpr,EP_Commuted)); 004873 assert(TK_LT==OP_Lt); testcase(op==OP_Lt); VdbeCoverageIf(v,op==OP_Lt); 004874 assert(TK_LE==OP_Le); testcase(op==OP_Le); VdbeCoverageIf(v,op==OP_Le); 004875 assert(TK_GT==OP_Gt); testcase(op==OP_Gt); VdbeCoverageIf(v,op==OP_Gt); 004876 assert(TK_GE==OP_Ge); testcase(op==OP_Ge); VdbeCoverageIf(v,op==OP_Ge); 004877 assert(TK_EQ==OP_Eq); testcase(op==OP_Eq); 004878 VdbeCoverageIf(v, op==OP_Eq && jumpIfNull!=SQLITE_NULLEQ); 004879 VdbeCoverageIf(v, op==OP_Eq && jumpIfNull==SQLITE_NULLEQ); 004880 assert(TK_NE==OP_Ne); testcase(op==OP_Ne); 004881 VdbeCoverageIf(v, op==OP_Ne && jumpIfNull!=SQLITE_NULLEQ); 004882 VdbeCoverageIf(v, op==OP_Ne && jumpIfNull==SQLITE_NULLEQ); 004883 testcase( regFree1==0 ); 004884 testcase( regFree2==0 ); 004885 break; 004886 } 004887 case TK_ISNULL: 004888 case TK_NOTNULL: { 004889 r1 = sqlite3ExprCodeTemp(pParse, pExpr->pLeft, ®Free1); 004890 sqlite3VdbeAddOp2(v, op, r1, dest); 004891 testcase( op==TK_ISNULL ); VdbeCoverageIf(v, op==TK_ISNULL); 004892 testcase( op==TK_NOTNULL ); VdbeCoverageIf(v, op==TK_NOTNULL); 004893 testcase( regFree1==0 ); 004894 break; 004895 } 004896 case TK_BETWEEN: { 004897 testcase( jumpIfNull==0 ); 004898 exprCodeBetween(pParse, pExpr, dest, sqlite3ExprIfFalse, jumpIfNull); 004899 break; 004900 } 004901 #ifndef SQLITE_OMIT_SUBQUERY 004902 case TK_IN: { 004903 if( jumpIfNull ){ 004904 sqlite3ExprCodeIN(pParse, pExpr, dest, dest); 004905 }else{ 004906 int destIfNull = sqlite3VdbeMakeLabel(pParse); 004907 sqlite3ExprCodeIN(pParse, pExpr, dest, destIfNull); 004908 sqlite3VdbeResolveLabel(v, destIfNull); 004909 } 004910 break; 004911 } 004912 #endif 004913 default: { 004914 default_expr: 004915 if( ExprAlwaysFalse(pExpr) ){ 004916 sqlite3VdbeGoto(v, dest); 004917 }else if( ExprAlwaysTrue(pExpr) ){ 004918 /* no-op */ 004919 }else{ 004920 r1 = sqlite3ExprCodeTemp(pParse, pExpr, ®Free1); 004921 sqlite3VdbeAddOp3(v, OP_IfNot, r1, dest, jumpIfNull!=0); 004922 VdbeCoverage(v); 004923 testcase( regFree1==0 ); 004924 testcase( jumpIfNull==0 ); 004925 } 004926 break; 004927 } 004928 } 004929 sqlite3ReleaseTempReg(pParse, regFree1); 004930 sqlite3ReleaseTempReg(pParse, regFree2); 004931 } 004932 004933 /* 004934 ** Like sqlite3ExprIfFalse() except that a copy is made of pExpr before 004935 ** code generation, and that copy is deleted after code generation. This 004936 ** ensures that the original pExpr is unchanged. 004937 */ 004938 void sqlite3ExprIfFalseDup(Parse *pParse, Expr *pExpr, int dest,int jumpIfNull){ 004939 sqlite3 *db = pParse->db; 004940 Expr *pCopy = sqlite3ExprDup(db, pExpr, 0); 004941 if( db->mallocFailed==0 ){ 004942 sqlite3ExprIfFalse(pParse, pCopy, dest, jumpIfNull); 004943 } 004944 sqlite3ExprDelete(db, pCopy); 004945 } 004946 004947 /* 004948 ** Expression pVar is guaranteed to be an SQL variable. pExpr may be any 004949 ** type of expression. 004950 ** 004951 ** If pExpr is a simple SQL value - an integer, real, string, blob 004952 ** or NULL value - then the VDBE currently being prepared is configured 004953 ** to re-prepare each time a new value is bound to variable pVar. 004954 ** 004955 ** Additionally, if pExpr is a simple SQL value and the value is the 004956 ** same as that currently bound to variable pVar, non-zero is returned. 004957 ** Otherwise, if the values are not the same or if pExpr is not a simple 004958 ** SQL value, zero is returned. 004959 */ 004960 static int exprCompareVariable(Parse *pParse, Expr *pVar, Expr *pExpr){ 004961 int res = 0; 004962 int iVar; 004963 sqlite3_value *pL, *pR = 0; 004964 004965 sqlite3ValueFromExpr(pParse->db, pExpr, SQLITE_UTF8, SQLITE_AFF_BLOB, &pR); 004966 if( pR ){ 004967 iVar = pVar->iColumn; 004968 sqlite3VdbeSetVarmask(pParse->pVdbe, iVar); 004969 pL = sqlite3VdbeGetBoundValue(pParse->pReprepare, iVar, SQLITE_AFF_BLOB); 004970 if( pL ){ 004971 if( sqlite3_value_type(pL)==SQLITE_TEXT ){ 004972 sqlite3_value_text(pL); /* Make sure the encoding is UTF-8 */ 004973 } 004974 res = 0==sqlite3MemCompare(pL, pR, 0); 004975 } 004976 sqlite3ValueFree(pR); 004977 sqlite3ValueFree(pL); 004978 } 004979 004980 return res; 004981 } 004982 004983 /* 004984 ** Do a deep comparison of two expression trees. Return 0 if the two 004985 ** expressions are completely identical. Return 1 if they differ only 004986 ** by a COLLATE operator at the top level. Return 2 if there are differences 004987 ** other than the top-level COLLATE operator. 004988 ** 004989 ** If any subelement of pB has Expr.iTable==(-1) then it is allowed 004990 ** to compare equal to an equivalent element in pA with Expr.iTable==iTab. 004991 ** 004992 ** The pA side might be using TK_REGISTER. If that is the case and pB is 004993 ** not using TK_REGISTER but is otherwise equivalent, then still return 0. 004994 ** 004995 ** Sometimes this routine will return 2 even if the two expressions 004996 ** really are equivalent. If we cannot prove that the expressions are 004997 ** identical, we return 2 just to be safe. So if this routine 004998 ** returns 2, then you do not really know for certain if the two 004999 ** expressions are the same. But if you get a 0 or 1 return, then you 005000 ** can be sure the expressions are the same. In the places where 005001 ** this routine is used, it does not hurt to get an extra 2 - that 005002 ** just might result in some slightly slower code. But returning 005003 ** an incorrect 0 or 1 could lead to a malfunction. 005004 ** 005005 ** If pParse is not NULL then TK_VARIABLE terms in pA with bindings in 005006 ** pParse->pReprepare can be matched against literals in pB. The 005007 ** pParse->pVdbe->expmask bitmask is updated for each variable referenced. 005008 ** If pParse is NULL (the normal case) then any TK_VARIABLE term in 005009 ** Argument pParse should normally be NULL. If it is not NULL and pA or 005010 ** pB causes a return value of 2. 005011 */ 005012 int sqlite3ExprCompare(Parse *pParse, Expr *pA, Expr *pB, int iTab){ 005013 u32 combinedFlags; 005014 if( pA==0 || pB==0 ){ 005015 return pB==pA ? 0 : 2; 005016 } 005017 if( pParse && pA->op==TK_VARIABLE && exprCompareVariable(pParse, pA, pB) ){ 005018 return 0; 005019 } 005020 combinedFlags = pA->flags | pB->flags; 005021 if( combinedFlags & EP_IntValue ){ 005022 if( (pA->flags&pB->flags&EP_IntValue)!=0 && pA->u.iValue==pB->u.iValue ){ 005023 return 0; 005024 } 005025 return 2; 005026 } 005027 if( pA->op!=pB->op || pA->op==TK_RAISE ){ 005028 if( pA->op==TK_COLLATE && sqlite3ExprCompare(pParse, pA->pLeft,pB,iTab)<2 ){ 005029 return 1; 005030 } 005031 if( pB->op==TK_COLLATE && sqlite3ExprCompare(pParse, pA,pB->pLeft,iTab)<2 ){ 005032 return 1; 005033 } 005034 return 2; 005035 } 005036 if( pA->op!=TK_COLUMN && pA->op!=TK_AGG_COLUMN && pA->u.zToken ){ 005037 if( pA->op==TK_FUNCTION || pA->op==TK_AGG_FUNCTION ){ 005038 if( sqlite3StrICmp(pA->u.zToken,pB->u.zToken)!=0 ) return 2; 005039 #ifndef SQLITE_OMIT_WINDOWFUNC 005040 assert( pA->op==pB->op ); 005041 if( ExprHasProperty(pA,EP_WinFunc)!=ExprHasProperty(pB,EP_WinFunc) ){ 005042 return 2; 005043 } 005044 if( ExprHasProperty(pA,EP_WinFunc) ){ 005045 if( sqlite3WindowCompare(pParse, pA->y.pWin, pB->y.pWin, 1)!=0 ){ 005046 return 2; 005047 } 005048 } 005049 #endif 005050 }else if( pA->op==TK_NULL ){ 005051 return 0; 005052 }else if( pA->op==TK_COLLATE ){ 005053 if( sqlite3_stricmp(pA->u.zToken,pB->u.zToken)!=0 ) return 2; 005054 }else if( ALWAYS(pB->u.zToken!=0) && strcmp(pA->u.zToken,pB->u.zToken)!=0 ){ 005055 return 2; 005056 } 005057 } 005058 if( (pA->flags & (EP_Distinct|EP_Commuted)) 005059 != (pB->flags & (EP_Distinct|EP_Commuted)) ) return 2; 005060 if( (combinedFlags & EP_TokenOnly)==0 ){ 005061 if( combinedFlags & EP_xIsSelect ) return 2; 005062 if( (combinedFlags & EP_FixedCol)==0 005063 && sqlite3ExprCompare(pParse, pA->pLeft, pB->pLeft, iTab) ) return 2; 005064 if( sqlite3ExprCompare(pParse, pA->pRight, pB->pRight, iTab) ) return 2; 005065 if( sqlite3ExprListCompare(pA->x.pList, pB->x.pList, iTab) ) return 2; 005066 if( pA->op!=TK_STRING 005067 && pA->op!=TK_TRUEFALSE 005068 && (combinedFlags & EP_Reduced)==0 005069 ){ 005070 if( pA->iColumn!=pB->iColumn ) return 2; 005071 if( pA->op2!=pB->op2 ){ 005072 if( pA->op==TK_TRUTH ) return 2; 005073 if( pA->op==TK_FUNCTION && iTab<0 ){ 005074 /* Ex: CREATE TABLE t1(a CHECK( a<julianday('now') )); 005075 ** INSERT INTO t1(a) VALUES(julianday('now')+10); 005076 ** Without this test, sqlite3ExprCodeAtInit() will run on the 005077 ** the julianday() of INSERT first, and remember that expression. 005078 ** Then sqlite3ExprCodeInit() will see the julianday() in the CHECK 005079 ** constraint as redundant, reusing the one from the INSERT, even 005080 ** though the julianday() in INSERT lacks the critical NC_IsCheck 005081 ** flag. See ticket [830277d9db6c3ba1] (2019-10-30) 005082 */ 005083 return 2; 005084 } 005085 } 005086 if( pA->op!=TK_IN && pA->iTable!=pB->iTable && pA->iTable!=iTab ){ 005087 return 2; 005088 } 005089 } 005090 } 005091 return 0; 005092 } 005093 005094 /* 005095 ** Compare two ExprList objects. Return 0 if they are identical and 005096 ** non-zero if they differ in any way. 005097 ** 005098 ** If any subelement of pB has Expr.iTable==(-1) then it is allowed 005099 ** to compare equal to an equivalent element in pA with Expr.iTable==iTab. 005100 ** 005101 ** This routine might return non-zero for equivalent ExprLists. The 005102 ** only consequence will be disabled optimizations. But this routine 005103 ** must never return 0 if the two ExprList objects are different, or 005104 ** a malfunction will result. 005105 ** 005106 ** Two NULL pointers are considered to be the same. But a NULL pointer 005107 ** always differs from a non-NULL pointer. 005108 */ 005109 int sqlite3ExprListCompare(ExprList *pA, ExprList *pB, int iTab){ 005110 int i; 005111 if( pA==0 && pB==0 ) return 0; 005112 if( pA==0 || pB==0 ) return 1; 005113 if( pA->nExpr!=pB->nExpr ) return 1; 005114 for(i=0; i<pA->nExpr; i++){ 005115 Expr *pExprA = pA->a[i].pExpr; 005116 Expr *pExprB = pB->a[i].pExpr; 005117 if( pA->a[i].sortFlags!=pB->a[i].sortFlags ) return 1; 005118 if( sqlite3ExprCompare(0, pExprA, pExprB, iTab) ) return 1; 005119 } 005120 return 0; 005121 } 005122 005123 /* 005124 ** Like sqlite3ExprCompare() except COLLATE operators at the top-level 005125 ** are ignored. 005126 */ 005127 int sqlite3ExprCompareSkip(Expr *pA, Expr *pB, int iTab){ 005128 return sqlite3ExprCompare(0, 005129 sqlite3ExprSkipCollateAndLikely(pA), 005130 sqlite3ExprSkipCollateAndLikely(pB), 005131 iTab); 005132 } 005133 005134 /* 005135 ** Return non-zero if Expr p can only be true if pNN is not NULL. 005136 ** 005137 ** Or if seenNot is true, return non-zero if Expr p can only be 005138 ** non-NULL if pNN is not NULL 005139 */ 005140 static int exprImpliesNotNull( 005141 Parse *pParse, /* Parsing context */ 005142 Expr *p, /* The expression to be checked */ 005143 Expr *pNN, /* The expression that is NOT NULL */ 005144 int iTab, /* Table being evaluated */ 005145 int seenNot /* Return true only if p can be any non-NULL value */ 005146 ){ 005147 assert( p ); 005148 assert( pNN ); 005149 if( sqlite3ExprCompare(pParse, p, pNN, iTab)==0 ){ 005150 return pNN->op!=TK_NULL; 005151 } 005152 switch( p->op ){ 005153 case TK_IN: { 005154 if( seenNot && ExprHasProperty(p, EP_xIsSelect) ) return 0; 005155 assert( ExprHasProperty(p,EP_xIsSelect) 005156 || (p->x.pList!=0 && p->x.pList->nExpr>0) ); 005157 return exprImpliesNotNull(pParse, p->pLeft, pNN, iTab, 1); 005158 } 005159 case TK_BETWEEN: { 005160 ExprList *pList = p->x.pList; 005161 assert( pList!=0 ); 005162 assert( pList->nExpr==2 ); 005163 if( seenNot ) return 0; 005164 if( exprImpliesNotNull(pParse, pList->a[0].pExpr, pNN, iTab, 1) 005165 || exprImpliesNotNull(pParse, pList->a[1].pExpr, pNN, iTab, 1) 005166 ){ 005167 return 1; 005168 } 005169 return exprImpliesNotNull(pParse, p->pLeft, pNN, iTab, 1); 005170 } 005171 case TK_EQ: 005172 case TK_NE: 005173 case TK_LT: 005174 case TK_LE: 005175 case TK_GT: 005176 case TK_GE: 005177 case TK_PLUS: 005178 case TK_MINUS: 005179 case TK_BITOR: 005180 case TK_LSHIFT: 005181 case TK_RSHIFT: 005182 case TK_CONCAT: 005183 seenNot = 1; 005184 /* Fall thru */ 005185 case TK_STAR: 005186 case TK_REM: 005187 case TK_BITAND: 005188 case TK_SLASH: { 005189 if( exprImpliesNotNull(pParse, p->pRight, pNN, iTab, seenNot) ) return 1; 005190 /* Fall thru into the next case */ 005191 } 005192 case TK_SPAN: 005193 case TK_COLLATE: 005194 case TK_UPLUS: 005195 case TK_UMINUS: { 005196 return exprImpliesNotNull(pParse, p->pLeft, pNN, iTab, seenNot); 005197 } 005198 case TK_TRUTH: { 005199 if( seenNot ) return 0; 005200 if( p->op2!=TK_IS ) return 0; 005201 return exprImpliesNotNull(pParse, p->pLeft, pNN, iTab, 1); 005202 } 005203 case TK_BITNOT: 005204 case TK_NOT: { 005205 return exprImpliesNotNull(pParse, p->pLeft, pNN, iTab, 1); 005206 } 005207 } 005208 return 0; 005209 } 005210 005211 /* 005212 ** Return true if we can prove the pE2 will always be true if pE1 is 005213 ** true. Return false if we cannot complete the proof or if pE2 might 005214 ** be false. Examples: 005215 ** 005216 ** pE1: x==5 pE2: x==5 Result: true 005217 ** pE1: x>0 pE2: x==5 Result: false 005218 ** pE1: x=21 pE2: x=21 OR y=43 Result: true 005219 ** pE1: x!=123 pE2: x IS NOT NULL Result: true 005220 ** pE1: x!=?1 pE2: x IS NOT NULL Result: true 005221 ** pE1: x IS NULL pE2: x IS NOT NULL Result: false 005222 ** pE1: x IS ?2 pE2: x IS NOT NULL Reuslt: false 005223 ** 005224 ** When comparing TK_COLUMN nodes between pE1 and pE2, if pE2 has 005225 ** Expr.iTable<0 then assume a table number given by iTab. 005226 ** 005227 ** If pParse is not NULL, then the values of bound variables in pE1 are 005228 ** compared against literal values in pE2 and pParse->pVdbe->expmask is 005229 ** modified to record which bound variables are referenced. If pParse 005230 ** is NULL, then false will be returned if pE1 contains any bound variables. 005231 ** 005232 ** When in doubt, return false. Returning true might give a performance 005233 ** improvement. Returning false might cause a performance reduction, but 005234 ** it will always give the correct answer and is hence always safe. 005235 */ 005236 int sqlite3ExprImpliesExpr(Parse *pParse, Expr *pE1, Expr *pE2, int iTab){ 005237 if( sqlite3ExprCompare(pParse, pE1, pE2, iTab)==0 ){ 005238 return 1; 005239 } 005240 if( pE2->op==TK_OR 005241 && (sqlite3ExprImpliesExpr(pParse, pE1, pE2->pLeft, iTab) 005242 || sqlite3ExprImpliesExpr(pParse, pE1, pE2->pRight, iTab) ) 005243 ){ 005244 return 1; 005245 } 005246 if( pE2->op==TK_NOTNULL 005247 && exprImpliesNotNull(pParse, pE1, pE2->pLeft, iTab, 0) 005248 ){ 005249 return 1; 005250 } 005251 return 0; 005252 } 005253 005254 /* 005255 ** This is the Expr node callback for sqlite3ExprImpliesNonNullRow(). 005256 ** If the expression node requires that the table at pWalker->iCur 005257 ** have one or more non-NULL column, then set pWalker->eCode to 1 and abort. 005258 ** 005259 ** This routine controls an optimization. False positives (setting 005260 ** pWalker->eCode to 1 when it should not be) are deadly, but false-negatives 005261 ** (never setting pWalker->eCode) is a harmless missed optimization. 005262 */ 005263 static int impliesNotNullRow(Walker *pWalker, Expr *pExpr){ 005264 testcase( pExpr->op==TK_AGG_COLUMN ); 005265 testcase( pExpr->op==TK_AGG_FUNCTION ); 005266 if( ExprHasProperty(pExpr, EP_FromJoin) ) return WRC_Prune; 005267 switch( pExpr->op ){ 005268 case TK_ISNOT: 005269 case TK_ISNULL: 005270 case TK_NOTNULL: 005271 case TK_IS: 005272 case TK_OR: 005273 case TK_VECTOR: 005274 case TK_CASE: 005275 case TK_IN: 005276 case TK_FUNCTION: 005277 case TK_TRUTH: 005278 testcase( pExpr->op==TK_ISNOT ); 005279 testcase( pExpr->op==TK_ISNULL ); 005280 testcase( pExpr->op==TK_NOTNULL ); 005281 testcase( pExpr->op==TK_IS ); 005282 testcase( pExpr->op==TK_OR ); 005283 testcase( pExpr->op==TK_VECTOR ); 005284 testcase( pExpr->op==TK_CASE ); 005285 testcase( pExpr->op==TK_IN ); 005286 testcase( pExpr->op==TK_FUNCTION ); 005287 testcase( pExpr->op==TK_TRUTH ); 005288 return WRC_Prune; 005289 case TK_COLUMN: 005290 if( pWalker->u.iCur==pExpr->iTable ){ 005291 pWalker->eCode = 1; 005292 return WRC_Abort; 005293 } 005294 return WRC_Prune; 005295 005296 case TK_AND: 005297 assert( pWalker->eCode==0 ); 005298 sqlite3WalkExpr(pWalker, pExpr->pLeft); 005299 if( pWalker->eCode ){ 005300 pWalker->eCode = 0; 005301 sqlite3WalkExpr(pWalker, pExpr->pRight); 005302 } 005303 return WRC_Prune; 005304 005305 case TK_BETWEEN: 005306 if( sqlite3WalkExpr(pWalker, pExpr->pLeft)==WRC_Abort ){ 005307 assert( pWalker->eCode ); 005308 return WRC_Abort; 005309 } 005310 return WRC_Prune; 005311 005312 /* Virtual tables are allowed to use constraints like x=NULL. So 005313 ** a term of the form x=y does not prove that y is not null if x 005314 ** is the column of a virtual table */ 005315 case TK_EQ: 005316 case TK_NE: 005317 case TK_LT: 005318 case TK_LE: 005319 case TK_GT: 005320 case TK_GE: 005321 testcase( pExpr->op==TK_EQ ); 005322 testcase( pExpr->op==TK_NE ); 005323 testcase( pExpr->op==TK_LT ); 005324 testcase( pExpr->op==TK_LE ); 005325 testcase( pExpr->op==TK_GT ); 005326 testcase( pExpr->op==TK_GE ); 005327 if( (pExpr->pLeft->op==TK_COLUMN && IsVirtual(pExpr->pLeft->y.pTab)) 005328 || (pExpr->pRight->op==TK_COLUMN && IsVirtual(pExpr->pRight->y.pTab)) 005329 ){ 005330 return WRC_Prune; 005331 } 005332 005333 default: 005334 return WRC_Continue; 005335 } 005336 } 005337 005338 /* 005339 ** Return true (non-zero) if expression p can only be true if at least 005340 ** one column of table iTab is non-null. In other words, return true 005341 ** if expression p will always be NULL or false if every column of iTab 005342 ** is NULL. 005343 ** 005344 ** False negatives are acceptable. In other words, it is ok to return 005345 ** zero even if expression p will never be true of every column of iTab 005346 ** is NULL. A false negative is merely a missed optimization opportunity. 005347 ** 005348 ** False positives are not allowed, however. A false positive may result 005349 ** in an incorrect answer. 005350 ** 005351 ** Terms of p that are marked with EP_FromJoin (and hence that come from 005352 ** the ON or USING clauses of LEFT JOINS) are excluded from the analysis. 005353 ** 005354 ** This routine is used to check if a LEFT JOIN can be converted into 005355 ** an ordinary JOIN. The p argument is the WHERE clause. If the WHERE 005356 ** clause requires that some column of the right table of the LEFT JOIN 005357 ** be non-NULL, then the LEFT JOIN can be safely converted into an 005358 ** ordinary join. 005359 */ 005360 int sqlite3ExprImpliesNonNullRow(Expr *p, int iTab){ 005361 Walker w; 005362 p = sqlite3ExprSkipCollateAndLikely(p); 005363 if( p==0 ) return 0; 005364 if( p->op==TK_NOTNULL ){ 005365 p = p->pLeft; 005366 }else{ 005367 while( p->op==TK_AND ){ 005368 if( sqlite3ExprImpliesNonNullRow(p->pLeft, iTab) ) return 1; 005369 p = p->pRight; 005370 } 005371 } 005372 w.xExprCallback = impliesNotNullRow; 005373 w.xSelectCallback = 0; 005374 w.xSelectCallback2 = 0; 005375 w.eCode = 0; 005376 w.u.iCur = iTab; 005377 sqlite3WalkExpr(&w, p); 005378 return w.eCode; 005379 } 005380 005381 /* 005382 ** An instance of the following structure is used by the tree walker 005383 ** to determine if an expression can be evaluated by reference to the 005384 ** index only, without having to do a search for the corresponding 005385 ** table entry. The IdxCover.pIdx field is the index. IdxCover.iCur 005386 ** is the cursor for the table. 005387 */ 005388 struct IdxCover { 005389 Index *pIdx; /* The index to be tested for coverage */ 005390 int iCur; /* Cursor number for the table corresponding to the index */ 005391 }; 005392 005393 /* 005394 ** Check to see if there are references to columns in table 005395 ** pWalker->u.pIdxCover->iCur can be satisfied using the index 005396 ** pWalker->u.pIdxCover->pIdx. 005397 */ 005398 static int exprIdxCover(Walker *pWalker, Expr *pExpr){ 005399 if( pExpr->op==TK_COLUMN 005400 && pExpr->iTable==pWalker->u.pIdxCover->iCur 005401 && sqlite3TableColumnToIndex(pWalker->u.pIdxCover->pIdx, pExpr->iColumn)<0 005402 ){ 005403 pWalker->eCode = 1; 005404 return WRC_Abort; 005405 } 005406 return WRC_Continue; 005407 } 005408 005409 /* 005410 ** Determine if an index pIdx on table with cursor iCur contains will 005411 ** the expression pExpr. Return true if the index does cover the 005412 ** expression and false if the pExpr expression references table columns 005413 ** that are not found in the index pIdx. 005414 ** 005415 ** An index covering an expression means that the expression can be 005416 ** evaluated using only the index and without having to lookup the 005417 ** corresponding table entry. 005418 */ 005419 int sqlite3ExprCoveredByIndex( 005420 Expr *pExpr, /* The index to be tested */ 005421 int iCur, /* The cursor number for the corresponding table */ 005422 Index *pIdx /* The index that might be used for coverage */ 005423 ){ 005424 Walker w; 005425 struct IdxCover xcov; 005426 memset(&w, 0, sizeof(w)); 005427 xcov.iCur = iCur; 005428 xcov.pIdx = pIdx; 005429 w.xExprCallback = exprIdxCover; 005430 w.u.pIdxCover = &xcov; 005431 sqlite3WalkExpr(&w, pExpr); 005432 return !w.eCode; 005433 } 005434 005435 005436 /* 005437 ** An instance of the following structure is used by the tree walker 005438 ** to count references to table columns in the arguments of an 005439 ** aggregate function, in order to implement the 005440 ** sqlite3FunctionThisSrc() routine. 005441 */ 005442 struct SrcCount { 005443 SrcList *pSrc; /* One particular FROM clause in a nested query */ 005444 int nThis; /* Number of references to columns in pSrcList */ 005445 int nOther; /* Number of references to columns in other FROM clauses */ 005446 }; 005447 005448 /* 005449 ** Count the number of references to columns. 005450 */ 005451 static int exprSrcCount(Walker *pWalker, Expr *pExpr){ 005452 /* There was once a NEVER() on the second term on the grounds that 005453 ** sqlite3FunctionUsesThisSrc() was always called before 005454 ** sqlite3ExprAnalyzeAggregates() and so the TK_COLUMNs have not yet 005455 ** been converted into TK_AGG_COLUMN. But this is no longer true due 005456 ** to window functions - sqlite3WindowRewrite() may now indirectly call 005457 ** FunctionUsesThisSrc() when creating a new sub-select. */ 005458 if( pExpr->op==TK_COLUMN || pExpr->op==TK_AGG_COLUMN ){ 005459 int i; 005460 struct SrcCount *p = pWalker->u.pSrcCount; 005461 SrcList *pSrc = p->pSrc; 005462 int nSrc = pSrc ? pSrc->nSrc : 0; 005463 for(i=0; i<nSrc; i++){ 005464 if( pExpr->iTable==pSrc->a[i].iCursor ) break; 005465 } 005466 if( i<nSrc ){ 005467 p->nThis++; 005468 }else if( nSrc==0 || pExpr->iTable<pSrc->a[0].iCursor ){ 005469 /* In a well-formed parse tree (no name resolution errors), 005470 ** TK_COLUMN nodes with smaller Expr.iTable values are in an 005471 ** outer context. Those are the only ones to count as "other" */ 005472 p->nOther++; 005473 } 005474 } 005475 return WRC_Continue; 005476 } 005477 005478 /* 005479 ** Determine if any of the arguments to the pExpr Function reference 005480 ** pSrcList. Return true if they do. Also return true if the function 005481 ** has no arguments or has only constant arguments. Return false if pExpr 005482 ** references columns but not columns of tables found in pSrcList. 005483 */ 005484 int sqlite3FunctionUsesThisSrc(Expr *pExpr, SrcList *pSrcList){ 005485 Walker w; 005486 struct SrcCount cnt; 005487 assert( pExpr->op==TK_AGG_FUNCTION ); 005488 memset(&w, 0, sizeof(w)); 005489 w.xExprCallback = exprSrcCount; 005490 w.xSelectCallback = sqlite3SelectWalkNoop; 005491 w.u.pSrcCount = &cnt; 005492 cnt.pSrc = pSrcList; 005493 cnt.nThis = 0; 005494 cnt.nOther = 0; 005495 sqlite3WalkExprList(&w, pExpr->x.pList); 005496 #ifndef SQLITE_OMIT_WINDOWFUNC 005497 if( ExprHasProperty(pExpr, EP_WinFunc) ){ 005498 sqlite3WalkExpr(&w, pExpr->y.pWin->pFilter); 005499 } 005500 #endif 005501 return cnt.nThis>0 || cnt.nOther==0; 005502 } 005503 005504 /* 005505 ** Add a new element to the pAggInfo->aCol[] array. Return the index of 005506 ** the new element. Return a negative number if malloc fails. 005507 */ 005508 static int addAggInfoColumn(sqlite3 *db, AggInfo *pInfo){ 005509 int i; 005510 pInfo->aCol = sqlite3ArrayAllocate( 005511 db, 005512 pInfo->aCol, 005513 sizeof(pInfo->aCol[0]), 005514 &pInfo->nColumn, 005515 &i 005516 ); 005517 return i; 005518 } 005519 005520 /* 005521 ** Add a new element to the pAggInfo->aFunc[] array. Return the index of 005522 ** the new element. Return a negative number if malloc fails. 005523 */ 005524 static int addAggInfoFunc(sqlite3 *db, AggInfo *pInfo){ 005525 int i; 005526 pInfo->aFunc = sqlite3ArrayAllocate( 005527 db, 005528 pInfo->aFunc, 005529 sizeof(pInfo->aFunc[0]), 005530 &pInfo->nFunc, 005531 &i 005532 ); 005533 return i; 005534 } 005535 005536 /* 005537 ** This is the xExprCallback for a tree walker. It is used to 005538 ** implement sqlite3ExprAnalyzeAggregates(). See sqlite3ExprAnalyzeAggregates 005539 ** for additional information. 005540 */ 005541 static int analyzeAggregate(Walker *pWalker, Expr *pExpr){ 005542 int i; 005543 NameContext *pNC = pWalker->u.pNC; 005544 Parse *pParse = pNC->pParse; 005545 SrcList *pSrcList = pNC->pSrcList; 005546 AggInfo *pAggInfo = pNC->uNC.pAggInfo; 005547 005548 assert( pNC->ncFlags & NC_UAggInfo ); 005549 switch( pExpr->op ){ 005550 case TK_AGG_COLUMN: 005551 case TK_COLUMN: { 005552 testcase( pExpr->op==TK_AGG_COLUMN ); 005553 testcase( pExpr->op==TK_COLUMN ); 005554 /* Check to see if the column is in one of the tables in the FROM 005555 ** clause of the aggregate query */ 005556 if( ALWAYS(pSrcList!=0) ){ 005557 struct SrcList_item *pItem = pSrcList->a; 005558 for(i=0; i<pSrcList->nSrc; i++, pItem++){ 005559 struct AggInfo_col *pCol; 005560 assert( !ExprHasProperty(pExpr, EP_TokenOnly|EP_Reduced) ); 005561 if( pExpr->iTable==pItem->iCursor ){ 005562 /* If we reach this point, it means that pExpr refers to a table 005563 ** that is in the FROM clause of the aggregate query. 005564 ** 005565 ** Make an entry for the column in pAggInfo->aCol[] if there 005566 ** is not an entry there already. 005567 */ 005568 int k; 005569 pCol = pAggInfo->aCol; 005570 for(k=0; k<pAggInfo->nColumn; k++, pCol++){ 005571 if( pCol->iTable==pExpr->iTable && 005572 pCol->iColumn==pExpr->iColumn ){ 005573 break; 005574 } 005575 } 005576 if( (k>=pAggInfo->nColumn) 005577 && (k = addAggInfoColumn(pParse->db, pAggInfo))>=0 005578 ){ 005579 pCol = &pAggInfo->aCol[k]; 005580 pCol->pTab = pExpr->y.pTab; 005581 pCol->iTable = pExpr->iTable; 005582 pCol->iColumn = pExpr->iColumn; 005583 pCol->iMem = ++pParse->nMem; 005584 pCol->iSorterColumn = -1; 005585 pCol->pExpr = pExpr; 005586 if( pAggInfo->pGroupBy ){ 005587 int j, n; 005588 ExprList *pGB = pAggInfo->pGroupBy; 005589 struct ExprList_item *pTerm = pGB->a; 005590 n = pGB->nExpr; 005591 for(j=0; j<n; j++, pTerm++){ 005592 Expr *pE = pTerm->pExpr; 005593 if( pE->op==TK_COLUMN && pE->iTable==pExpr->iTable && 005594 pE->iColumn==pExpr->iColumn ){ 005595 pCol->iSorterColumn = j; 005596 break; 005597 } 005598 } 005599 } 005600 if( pCol->iSorterColumn<0 ){ 005601 pCol->iSorterColumn = pAggInfo->nSortingColumn++; 005602 } 005603 } 005604 /* There is now an entry for pExpr in pAggInfo->aCol[] (either 005605 ** because it was there before or because we just created it). 005606 ** Convert the pExpr to be a TK_AGG_COLUMN referring to that 005607 ** pAggInfo->aCol[] entry. 005608 */ 005609 ExprSetVVAProperty(pExpr, EP_NoReduce); 005610 pExpr->pAggInfo = pAggInfo; 005611 pExpr->op = TK_AGG_COLUMN; 005612 pExpr->iAgg = (i16)k; 005613 break; 005614 } /* endif pExpr->iTable==pItem->iCursor */ 005615 } /* end loop over pSrcList */ 005616 } 005617 return WRC_Prune; 005618 } 005619 case TK_AGG_FUNCTION: { 005620 if( (pNC->ncFlags & NC_InAggFunc)==0 005621 && pWalker->walkerDepth==pExpr->op2 005622 ){ 005623 /* Check to see if pExpr is a duplicate of another aggregate 005624 ** function that is already in the pAggInfo structure 005625 */ 005626 struct AggInfo_func *pItem = pAggInfo->aFunc; 005627 for(i=0; i<pAggInfo->nFunc; i++, pItem++){ 005628 if( sqlite3ExprCompare(0, pItem->pExpr, pExpr, -1)==0 ){ 005629 break; 005630 } 005631 } 005632 if( i>=pAggInfo->nFunc ){ 005633 /* pExpr is original. Make a new entry in pAggInfo->aFunc[] 005634 */ 005635 u8 enc = ENC(pParse->db); 005636 i = addAggInfoFunc(pParse->db, pAggInfo); 005637 if( i>=0 ){ 005638 assert( !ExprHasProperty(pExpr, EP_xIsSelect) ); 005639 pItem = &pAggInfo->aFunc[i]; 005640 pItem->pExpr = pExpr; 005641 pItem->iMem = ++pParse->nMem; 005642 assert( !ExprHasProperty(pExpr, EP_IntValue) ); 005643 pItem->pFunc = sqlite3FindFunction(pParse->db, 005644 pExpr->u.zToken, 005645 pExpr->x.pList ? pExpr->x.pList->nExpr : 0, enc, 0); 005646 if( pExpr->flags & EP_Distinct ){ 005647 pItem->iDistinct = pParse->nTab++; 005648 }else{ 005649 pItem->iDistinct = -1; 005650 } 005651 } 005652 } 005653 /* Make pExpr point to the appropriate pAggInfo->aFunc[] entry 005654 */ 005655 assert( !ExprHasProperty(pExpr, EP_TokenOnly|EP_Reduced) ); 005656 ExprSetVVAProperty(pExpr, EP_NoReduce); 005657 pExpr->iAgg = (i16)i; 005658 pExpr->pAggInfo = pAggInfo; 005659 return WRC_Prune; 005660 }else{ 005661 return WRC_Continue; 005662 } 005663 } 005664 } 005665 return WRC_Continue; 005666 } 005667 static int analyzeAggregatesInSelect(Walker *pWalker, Select *pSelect){ 005668 UNUSED_PARAMETER(pSelect); 005669 pWalker->walkerDepth++; 005670 return WRC_Continue; 005671 } 005672 static void analyzeAggregatesInSelectEnd(Walker *pWalker, Select *pSelect){ 005673 UNUSED_PARAMETER(pSelect); 005674 pWalker->walkerDepth--; 005675 } 005676 005677 /* 005678 ** Analyze the pExpr expression looking for aggregate functions and 005679 ** for variables that need to be added to AggInfo object that pNC->pAggInfo 005680 ** points to. Additional entries are made on the AggInfo object as 005681 ** necessary. 005682 ** 005683 ** This routine should only be called after the expression has been 005684 ** analyzed by sqlite3ResolveExprNames(). 005685 */ 005686 void sqlite3ExprAnalyzeAggregates(NameContext *pNC, Expr *pExpr){ 005687 Walker w; 005688 w.xExprCallback = analyzeAggregate; 005689 w.xSelectCallback = analyzeAggregatesInSelect; 005690 w.xSelectCallback2 = analyzeAggregatesInSelectEnd; 005691 w.walkerDepth = 0; 005692 w.u.pNC = pNC; 005693 w.pParse = 0; 005694 assert( pNC->pSrcList!=0 ); 005695 sqlite3WalkExpr(&w, pExpr); 005696 } 005697 005698 /* 005699 ** Call sqlite3ExprAnalyzeAggregates() for every expression in an 005700 ** expression list. Return the number of errors. 005701 ** 005702 ** If an error is found, the analysis is cut short. 005703 */ 005704 void sqlite3ExprAnalyzeAggList(NameContext *pNC, ExprList *pList){ 005705 struct ExprList_item *pItem; 005706 int i; 005707 if( pList ){ 005708 for(pItem=pList->a, i=0; i<pList->nExpr; i++, pItem++){ 005709 sqlite3ExprAnalyzeAggregates(pNC, pItem->pExpr); 005710 } 005711 } 005712 } 005713 005714 /* 005715 ** Allocate a single new register for use to hold some intermediate result. 005716 */ 005717 int sqlite3GetTempReg(Parse *pParse){ 005718 if( pParse->nTempReg==0 ){ 005719 return ++pParse->nMem; 005720 } 005721 return pParse->aTempReg[--pParse->nTempReg]; 005722 } 005723 005724 /* 005725 ** Deallocate a register, making available for reuse for some other 005726 ** purpose. 005727 */ 005728 void sqlite3ReleaseTempReg(Parse *pParse, int iReg){ 005729 if( iReg ){ 005730 sqlite3VdbeReleaseRegisters(pParse, iReg, 1, 0); 005731 if( pParse->nTempReg<ArraySize(pParse->aTempReg) ){ 005732 pParse->aTempReg[pParse->nTempReg++] = iReg; 005733 } 005734 } 005735 } 005736 005737 /* 005738 ** Allocate or deallocate a block of nReg consecutive registers. 005739 */ 005740 int sqlite3GetTempRange(Parse *pParse, int nReg){ 005741 int i, n; 005742 if( nReg==1 ) return sqlite3GetTempReg(pParse); 005743 i = pParse->iRangeReg; 005744 n = pParse->nRangeReg; 005745 if( nReg<=n ){ 005746 pParse->iRangeReg += nReg; 005747 pParse->nRangeReg -= nReg; 005748 }else{ 005749 i = pParse->nMem+1; 005750 pParse->nMem += nReg; 005751 } 005752 return i; 005753 } 005754 void sqlite3ReleaseTempRange(Parse *pParse, int iReg, int nReg){ 005755 if( nReg==1 ){ 005756 sqlite3ReleaseTempReg(pParse, iReg); 005757 return; 005758 } 005759 sqlite3VdbeReleaseRegisters(pParse, iReg, nReg, 0); 005760 if( nReg>pParse->nRangeReg ){ 005761 pParse->nRangeReg = nReg; 005762 pParse->iRangeReg = iReg; 005763 } 005764 } 005765 005766 /* 005767 ** Mark all temporary registers as being unavailable for reuse. 005768 ** 005769 ** Always invoke this procedure after coding a subroutine or co-routine 005770 ** that might be invoked from other parts of the code, to ensure that 005771 ** the sub/co-routine does not use registers in common with the code that 005772 ** invokes the sub/co-routine. 005773 */ 005774 void sqlite3ClearTempRegCache(Parse *pParse){ 005775 pParse->nTempReg = 0; 005776 pParse->nRangeReg = 0; 005777 } 005778 005779 /* 005780 ** Validate that no temporary register falls within the range of 005781 ** iFirst..iLast, inclusive. This routine is only call from within assert() 005782 ** statements. 005783 */ 005784 #ifdef SQLITE_DEBUG 005785 int sqlite3NoTempsInRange(Parse *pParse, int iFirst, int iLast){ 005786 int i; 005787 if( pParse->nRangeReg>0 005788 && pParse->iRangeReg+pParse->nRangeReg > iFirst 005789 && pParse->iRangeReg <= iLast 005790 ){ 005791 return 0; 005792 } 005793 for(i=0; i<pParse->nTempReg; i++){ 005794 if( pParse->aTempReg[i]>=iFirst && pParse->aTempReg[i]<=iLast ){ 005795 return 0; 005796 } 005797 } 005798 return 1; 005799 } 005800 #endif /* SQLITE_DEBUG */