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Diffstat (limited to 'kexi/3rdparty/kexisql3/src/expr.c')
| -rw-r--r-- | kexi/3rdparty/kexisql3/src/expr.c | 2253 |
1 files changed, 2253 insertions, 0 deletions
diff --git a/kexi/3rdparty/kexisql3/src/expr.c b/kexi/3rdparty/kexisql3/src/expr.c new file mode 100644 index 00000000..45f7fc2f --- /dev/null +++ b/kexi/3rdparty/kexisql3/src/expr.c @@ -0,0 +1,2253 @@ +/* +** 2001 September 15 +** +** The author disclaims copyright to this source code. In place of +** a legal notice, here is a blessing: +** +** May you do good and not evil. +** May you find forgiveness for yourself and forgive others. +** May you share freely, never taking more than you give. +** +************************************************************************* +** This file contains routines used for analyzing expressions and +** for generating VDBE code that evaluates expressions in SQLite. +** +** $Id: expr.c 653457 2007-04-13 11:18:02Z scripty $ +*/ +#include "sqliteInt.h" +#include <ctype.h> + +/* +** Return the 'affinity' of the expression pExpr if any. +** +** If pExpr is a column, a reference to a column via an 'AS' alias, +** or a sub-select with a column as the return value, then the +** affinity of that column is returned. Otherwise, 0x00 is returned, +** indicating no affinity for the expression. +** +** i.e. the WHERE clause expresssions in the following statements all +** have an affinity: +** +** CREATE TABLE t1(a); +** SELECT * FROM t1 WHERE a; +** SELECT a AS b FROM t1 WHERE b; +** SELECT * FROM t1 WHERE (select a from t1); +*/ +char sqlite3ExprAffinity(Expr *pExpr){ + int op = pExpr->op; + if( op==TK_AS ){ + return sqlite3ExprAffinity(pExpr->pLeft); + } + if( op==TK_SELECT ){ + return sqlite3ExprAffinity(pExpr->pSelect->pEList->a[0].pExpr); + } +#ifndef SQLITE_OMIT_CAST + if( op==TK_CAST ){ + return sqlite3AffinityType(&pExpr->token); + } +#endif + return pExpr->affinity; +} + +/* +** Return the default collation sequence for the expression pExpr. If +** there is no default collation type, return 0. +*/ +CollSeq *sqlite3ExprCollSeq(Parse *pParse, Expr *pExpr){ + CollSeq *pColl = 0; + if( pExpr ){ + pColl = pExpr->pColl; + if( (pExpr->op==TK_AS || pExpr->op==TK_CAST) && !pColl ){ + return sqlite3ExprCollSeq(pParse, pExpr->pLeft); + } + } + if( sqlite3CheckCollSeq(pParse, pColl) ){ + pColl = 0; + } + return pColl; +} + +/* +** pExpr is an operand of a comparison operator. aff2 is the +** type affinity of the other operand. This routine returns the +** type affinity that should be used for the comparison operator. +*/ +char sqlite3CompareAffinity(Expr *pExpr, char aff2){ + char aff1 = sqlite3ExprAffinity(pExpr); + if( aff1 && aff2 ){ + /* Both sides of the comparison are columns. If one has numeric or + ** integer affinity, use that. Otherwise use no affinity. + */ + if( aff1==SQLITE_AFF_INTEGER || aff2==SQLITE_AFF_INTEGER ){ + return SQLITE_AFF_INTEGER; + }else if( aff1==SQLITE_AFF_NUMERIC || aff2==SQLITE_AFF_NUMERIC ){ + return SQLITE_AFF_NUMERIC; + }else{ + return SQLITE_AFF_NONE; + } + }else if( !aff1 && !aff2 ){ + /* Neither side of the comparison is a column. Compare the + ** results directly. + */ + /* return SQLITE_AFF_NUMERIC; // Ticket #805 */ + return SQLITE_AFF_NONE; + }else{ + /* One side is a column, the other is not. Use the columns affinity. */ + assert( aff1==0 || aff2==0 ); + return (aff1 + aff2); + } +} + +/* +** pExpr is a comparison operator. Return the type affinity that should +** be applied to both operands prior to doing the comparison. +*/ +static char comparisonAffinity(Expr *pExpr){ + char aff; + assert( pExpr->op==TK_EQ || pExpr->op==TK_IN || pExpr->op==TK_LT || + pExpr->op==TK_GT || pExpr->op==TK_GE || pExpr->op==TK_LE || + pExpr->op==TK_NE ); + assert( pExpr->pLeft ); + aff = sqlite3ExprAffinity(pExpr->pLeft); + if( pExpr->pRight ){ + aff = sqlite3CompareAffinity(pExpr->pRight, aff); + } + else if( pExpr->pSelect ){ + aff = sqlite3CompareAffinity(pExpr->pSelect->pEList->a[0].pExpr, aff); + } + else if( !aff ){ + aff = SQLITE_AFF_NUMERIC; + } + return aff; +} + +/* +** pExpr is a comparison expression, eg. '=', '<', IN(...) etc. +** idx_affinity is the affinity of an indexed column. Return true +** if the index with affinity idx_affinity may be used to implement +** the comparison in pExpr. +*/ +int sqlite3IndexAffinityOk(Expr *pExpr, char idx_affinity){ + char aff = comparisonAffinity(pExpr); + return + (aff==SQLITE_AFF_NONE) || + (aff==SQLITE_AFF_NUMERIC && idx_affinity==SQLITE_AFF_INTEGER) || + (aff==SQLITE_AFF_INTEGER && idx_affinity==SQLITE_AFF_NUMERIC) || + (aff==idx_affinity); +} + +/* +** Return the P1 value that should be used for a binary comparison +** opcode (OP_Eq, OP_Ge etc.) used to compare pExpr1 and pExpr2. +** If jumpIfNull is true, then set the low byte of the returned +** P1 value to tell the opcode to jump if either expression +** evaluates to NULL. +*/ +static int binaryCompareP1(Expr *pExpr1, Expr *pExpr2, int jumpIfNull){ + char aff = sqlite3ExprAffinity(pExpr2); + return ((int)sqlite3CompareAffinity(pExpr1, aff))+(jumpIfNull?0x100:0); +} + +/* +** Return a pointer to the collation sequence that should be used by +** a binary comparison operator comparing pLeft and pRight. +** +** If the left hand expression has a collating sequence type, then it is +** used. Otherwise the collation sequence for the right hand expression +** is used, or the default (BINARY) if neither expression has a collating +** type. +*/ +static CollSeq* binaryCompareCollSeq(Parse *pParse, Expr *pLeft, Expr *pRight){ + CollSeq *pColl = sqlite3ExprCollSeq(pParse, pLeft); + if( !pColl ){ + pColl = sqlite3ExprCollSeq(pParse, pRight); + } + return pColl; +} + +/* +** Generate code for a comparison operator. +*/ +static int codeCompare( + Parse *pParse, /* The parsing (and code generating) context */ + Expr *pLeft, /* The left operand */ + Expr *pRight, /* The right operand */ + int opcode, /* The comparison opcode */ + int dest, /* Jump here if true. */ + int jumpIfNull /* If true, jump if either operand is NULL */ +){ + int p1 = binaryCompareP1(pLeft, pRight, jumpIfNull); + CollSeq *p3 = binaryCompareCollSeq(pParse, pLeft, pRight); + return sqlite3VdbeOp3(pParse->pVdbe, opcode, p1, dest, (void*)p3, P3_COLLSEQ); +} + +/* +** Construct a new expression node and return a pointer to it. Memory +** for this node is obtained from sqliteMalloc(). The calling function +** is responsible for making sure the node eventually gets freed. +*/ +Expr *sqlite3Expr(int op, Expr *pLeft, Expr *pRight, const Token *pToken){ + Expr *pNew; + pNew = sqliteMalloc( sizeof(Expr) ); + if( pNew==0 ){ + /* When malloc fails, delete pLeft and pRight. Expressions passed to + ** this function must always be allocated with sqlite3Expr() for this + ** reason. + */ + sqlite3ExprDelete(pLeft); + sqlite3ExprDelete(pRight); + return 0; + } + pNew->op = op; + pNew->pLeft = pLeft; + pNew->pRight = pRight; + pNew->iAgg = -1; + if( pToken ){ + assert( pToken->dyn==0 ); + pNew->span = pNew->token = *pToken; + }else if( pLeft && pRight ){ + sqlite3ExprSpan(pNew, &pLeft->span, &pRight->span); + } + return pNew; +} + +/* +** When doing a nested parse, you can include terms in an expression +** that look like this: #0 #1 #2 ... These terms refer to elements +** on the stack. "#0" means the top of the stack. +** "#1" means the next down on the stack. And so forth. +** +** This routine is called by the parser to deal with on of those terms. +** It immediately generates code to store the value in a memory location. +** The returns an expression that will code to extract the value from +** that memory location as needed. +*/ +Expr *sqlite3RegisterExpr(Parse *pParse, Token *pToken){ + Vdbe *v = pParse->pVdbe; + Expr *p; + int depth; + if( pParse->nested==0 ){ + sqlite3ErrorMsg(pParse, "near \"%T\": syntax error", pToken); + return 0; + } + if( v==0 ) return 0; + p = sqlite3Expr(TK_REGISTER, 0, 0, pToken); + if( p==0 ){ + return 0; /* Malloc failed */ + } + depth = atoi(&pToken->z[1]); + p->iTable = pParse->nMem++; + sqlite3VdbeAddOp(v, OP_Dup, depth, 0); + sqlite3VdbeAddOp(v, OP_MemStore, p->iTable, 1); + return p; +} + +/* +** Join two expressions using an AND operator. If either expression is +** NULL, then just return the other expression. +*/ +Expr *sqlite3ExprAnd(Expr *pLeft, Expr *pRight){ + if( pLeft==0 ){ + return pRight; + }else if( pRight==0 ){ + return pLeft; + }else{ + return sqlite3Expr(TK_AND, pLeft, pRight, 0); + } +} + +/* +** Set the Expr.span field of the given expression to span all +** text between the two given tokens. +*/ +void sqlite3ExprSpan(Expr *pExpr, Token *pLeft, Token *pRight){ + assert( pRight!=0 ); + assert( pLeft!=0 ); + if( !sqlite3_malloc_failed && pRight->z && pLeft->z ){ + assert( pLeft->dyn==0 || pLeft->z[pLeft->n]==0 ); + if( pLeft->dyn==0 && pRight->dyn==0 ){ + pExpr->span.z = pLeft->z; + pExpr->span.n = pRight->n + (pRight->z - pLeft->z); + }else{ + pExpr->span.z = 0; + } + } +} + +/* +** Construct a new expression node for a function with multiple +** arguments. +*/ +Expr *sqlite3ExprFunction(ExprList *pList, Token *pToken){ + Expr *pNew; + pNew = sqliteMalloc( sizeof(Expr) ); + if( pNew==0 ){ + sqlite3ExprListDelete(pList); /* Avoid leaking memory when malloc fails */ + return 0; + } + pNew->op = TK_FUNCTION; + pNew->pList = pList; + if( pToken ){ + assert( pToken->dyn==0 ); + pNew->token = *pToken; + }else{ + pNew->token.z = 0; + } + pNew->span = pNew->token; + return pNew; +} + +/* +** Assign a variable number to an expression that encodes a wildcard +** in the original SQL statement. +** +** Wildcards consisting of a single "?" are assigned the next sequential +** variable number. +** +** Wildcards of the form "?nnn" are assigned the number "nnn". We make +** sure "nnn" is not too be to avoid a denial of service attack when +** the SQL statement comes from an external source. +** +** Wildcards of the form ":aaa" or "$aaa" are assigned the same number +** as the previous instance of the same wildcard. Or if this is the first +** instance of the wildcard, the next sequenial variable number is +** assigned. +*/ +void sqlite3ExprAssignVarNumber(Parse *pParse, Expr *pExpr){ + Token *pToken; + if( pExpr==0 ) return; + pToken = &pExpr->token; + assert( pToken->n>=1 ); + assert( pToken->z!=0 ); + assert( pToken->z[0]!=0 ); + if( pToken->n==1 ){ + /* Wildcard of the form "?". Assign the next variable number */ + pExpr->iTable = ++pParse->nVar; + }else if( pToken->z[0]=='?' ){ + /* Wildcard of the form "?nnn". Convert "nnn" to an integer and + ** use it as the variable number */ + int i; + pExpr->iTable = i = atoi(&pToken->z[1]); + if( i<1 || i>SQLITE_MAX_VARIABLE_NUMBER ){ + sqlite3ErrorMsg(pParse, "variable number must be between ?1 and ?%d", + SQLITE_MAX_VARIABLE_NUMBER); + } + if( i>pParse->nVar ){ + pParse->nVar = i; + } + }else{ + /* Wildcards of the form ":aaa" or "$aaa". Reuse the same variable + ** number as the prior appearance of the same name, or if the name + ** has never appeared before, reuse the same variable number + */ + int i, n; + n = pToken->n; + for(i=0; i<pParse->nVarExpr; i++){ + Expr *pE; + if( (pE = pParse->apVarExpr[i])!=0 + && pE->token.n==n + && memcmp(pE->token.z, pToken->z, n)==0 ){ + pExpr->iTable = pE->iTable; + break; + } + } + if( i>=pParse->nVarExpr ){ + pExpr->iTable = ++pParse->nVar; + if( pParse->nVarExpr>=pParse->nVarExprAlloc-1 ){ + pParse->nVarExprAlloc += pParse->nVarExprAlloc + 10; + sqlite3ReallocOrFree((void**)&pParse->apVarExpr, + pParse->nVarExprAlloc*sizeof(pParse->apVarExpr[0]) ); + } + if( !sqlite3_malloc_failed ){ + assert( pParse->apVarExpr!=0 ); + pParse->apVarExpr[pParse->nVarExpr++] = pExpr; + } + } + } +} + +/* +** Recursively delete an expression tree. +*/ +void sqlite3ExprDelete(Expr *p){ + if( p==0 ) return; + if( p->span.dyn ) sqliteFree((char*)p->span.z); + if( p->token.dyn ) sqliteFree((char*)p->token.z); + sqlite3ExprDelete(p->pLeft); + sqlite3ExprDelete(p->pRight); + sqlite3ExprListDelete(p->pList); + sqlite3SelectDelete(p->pSelect); + sqliteFree(p); +} + +/* +** The Expr.token field might be a string literal that is quoted. +** If so, remove the quotation marks. +*/ +void sqlite3DequoteExpr(Expr *p){ + if( ExprHasAnyProperty(p, EP_Dequoted) ){ + return; + } + ExprSetProperty(p, EP_Dequoted); + if( p->token.dyn==0 ){ + sqlite3TokenCopy(&p->token, &p->token); + } + sqlite3Dequote((char*)p->token.z); +} + + +/* +** The following group of routines make deep copies of expressions, +** expression lists, ID lists, and select statements. The copies can +** be deleted (by being passed to their respective ...Delete() routines) +** without effecting the originals. +** +** The expression list, ID, and source lists return by sqlite3ExprListDup(), +** sqlite3IdListDup(), and sqlite3SrcListDup() can not be further expanded +** by subsequent calls to sqlite*ListAppend() routines. +** +** Any tables that the SrcList might point to are not duplicated. +*/ +Expr *sqlite3ExprDup(Expr *p){ + Expr *pNew; + if( p==0 ) return 0; + pNew = sqliteMallocRaw( sizeof(*p) ); + if( pNew==0 ) return 0; + memcpy(pNew, p, sizeof(*pNew)); + if( p->token.z!=0 ){ + pNew->token.z = sqliteStrNDup(p->token.z, p->token.n); + pNew->token.dyn = 1; + }else{ + assert( pNew->token.z==0 ); + } + pNew->span.z = 0; + pNew->pLeft = sqlite3ExprDup(p->pLeft); + pNew->pRight = sqlite3ExprDup(p->pRight); + pNew->pList = sqlite3ExprListDup(p->pList); + pNew->pSelect = sqlite3SelectDup(p->pSelect); + pNew->pTab = p->pTab; + return pNew; +} +void sqlite3TokenCopy(Token *pTo, Token *pFrom){ + if( pTo->dyn ) sqliteFree((char*)pTo->z); + if( pFrom->z ){ + pTo->n = pFrom->n; + pTo->z = sqliteStrNDup(pFrom->z, pFrom->n); + pTo->dyn = 1; + }else{ + pTo->z = 0; + } +} +ExprList *sqlite3ExprListDup(ExprList *p){ + ExprList *pNew; + struct ExprList_item *pItem, *pOldItem; + int i; + if( p==0 ) return 0; + pNew = sqliteMalloc( sizeof(*pNew) ); + if( pNew==0 ) return 0; + pNew->nExpr = pNew->nAlloc = p->nExpr; + pNew->a = pItem = sqliteMalloc( p->nExpr*sizeof(p->a[0]) ); + if( pItem==0 ){ + sqliteFree(pNew); + return 0; + } + pOldItem = p->a; + for(i=0; i<p->nExpr; i++, pItem++, pOldItem++){ + Expr *pNewExpr, *pOldExpr; + pItem->pExpr = pNewExpr = sqlite3ExprDup(pOldExpr = pOldItem->pExpr); + if( pOldExpr->span.z!=0 && pNewExpr ){ + /* Always make a copy of the span for top-level expressions in the + ** expression list. The logic in SELECT processing that determines + ** the names of columns in the result set needs this information */ + sqlite3TokenCopy(&pNewExpr->span, &pOldExpr->span); + } + assert( pNewExpr==0 || pNewExpr->span.z!=0 + || pOldExpr->span.z==0 || sqlite3_malloc_failed ); + pItem->zName = sqliteStrDup(pOldItem->zName); + pItem->sortOrder = pOldItem->sortOrder; + pItem->isAgg = pOldItem->isAgg; + pItem->done = 0; + } + return pNew; +} + +/* +** If cursors, triggers, views and subqueries are all omitted from +** the build, then none of the following routines, except for +** sqlite3SelectDup(), can be called. sqlite3SelectDup() is sometimes +** called with a NULL argument. +*/ +#if !defined(SQLITE_OMIT_VIEW) || !defined(SQLITE_OMIT_TRIGGER) \ + || !defined(SQLITE_OMIT_SUBQUERY) +SrcList *sqlite3SrcListDup(SrcList *p){ + SrcList *pNew; + int i; + int nByte; + if( p==0 ) return 0; + nByte = sizeof(*p) + (p->nSrc>0 ? sizeof(p->a[0]) * (p->nSrc-1) : 0); + pNew = sqliteMallocRaw( nByte ); + if( pNew==0 ) return 0; + pNew->nSrc = pNew->nAlloc = p->nSrc; + for(i=0; i<p->nSrc; i++){ + struct SrcList_item *pNewItem = &pNew->a[i]; + struct SrcList_item *pOldItem = &p->a[i]; + Table *pTab; + pNewItem->zDatabase = sqliteStrDup(pOldItem->zDatabase); + pNewItem->zName = sqliteStrDup(pOldItem->zName); + pNewItem->zAlias = sqliteStrDup(pOldItem->zAlias); + pNewItem->jointype = pOldItem->jointype; + pNewItem->iCursor = pOldItem->iCursor; + pTab = pNewItem->pTab = pOldItem->pTab; + if( pTab ){ + pTab->nRef++; + } + pNewItem->pSelect = sqlite3SelectDup(pOldItem->pSelect); + pNewItem->pOn = sqlite3ExprDup(pOldItem->pOn); + pNewItem->pUsing = sqlite3IdListDup(pOldItem->pUsing); + pNewItem->colUsed = pOldItem->colUsed; + } + return pNew; +} +IdList *sqlite3IdListDup(IdList *p){ + IdList *pNew; + int i; + if( p==0 ) return 0; + pNew = sqliteMallocRaw( sizeof(*pNew) ); + if( pNew==0 ) return 0; + pNew->nId = pNew->nAlloc = p->nId; + pNew->a = sqliteMallocRaw( p->nId*sizeof(p->a[0]) ); + if( pNew->a==0 ){ + sqliteFree(pNew); + return 0; + } + for(i=0; i<p->nId; i++){ + struct IdList_item *pNewItem = &pNew->a[i]; + struct IdList_item *pOldItem = &p->a[i]; + pNewItem->zName = sqliteStrDup(pOldItem->zName); + pNewItem->idx = pOldItem->idx; + } + return pNew; +} +Select *sqlite3SelectDup(Select *p){ + Select *pNew; + if( p==0 ) return 0; + pNew = sqliteMallocRaw( sizeof(*p) ); + if( pNew==0 ) return 0; + pNew->isDistinct = p->isDistinct; + pNew->pEList = sqlite3ExprListDup(p->pEList); + pNew->pSrc = sqlite3SrcListDup(p->pSrc); + pNew->pWhere = sqlite3ExprDup(p->pWhere); + pNew->pGroupBy = sqlite3ExprListDup(p->pGroupBy); + pNew->pHaving = sqlite3ExprDup(p->pHaving); + pNew->pOrderBy = sqlite3ExprListDup(p->pOrderBy); + pNew->op = p->op; + pNew->pPrior = sqlite3SelectDup(p->pPrior); + pNew->pLimit = sqlite3ExprDup(p->pLimit); + pNew->pOffset = sqlite3ExprDup(p->pOffset); + pNew->iLimit = -1; + pNew->iOffset = -1; + pNew->isResolved = p->isResolved; + pNew->isAgg = p->isAgg; + pNew->usesVirt = 0; + pNew->disallowOrderBy = 0; + pNew->pRightmost = 0; + pNew->addrOpenVirt[0] = -1; + pNew->addrOpenVirt[1] = -1; + pNew->addrOpenVirt[2] = -1; + return pNew; +} +#else +Select *sqlite3SelectDup(Select *p){ + assert( p==0 ); + return 0; +} +#endif + + +/* +** Add a new element to the end of an expression list. If pList is +** initially NULL, then create a new expression list. +*/ +ExprList *sqlite3ExprListAppend(ExprList *pList, Expr *pExpr, Token *pName){ + if( pList==0 ){ + pList = sqliteMalloc( sizeof(ExprList) ); + if( pList==0 ){ + goto no_mem; + } + assert( pList->nAlloc==0 ); + } + if( pList->nAlloc<=pList->nExpr ){ + struct ExprList_item *a; + int n = pList->nAlloc*2 + 4; + a = sqliteRealloc(pList->a, n*sizeof(pList->a[0])); + if( a==0 ){ + goto no_mem; + } + pList->a = a; + pList->nAlloc = n; + } + assert( pList->a!=0 ); + if( pExpr || pName ){ + struct ExprList_item *pItem = &pList->a[pList->nExpr++]; + memset(pItem, 0, sizeof(*pItem)); + pItem->zName = sqlite3NameFromToken(pName); + pItem->pExpr = pExpr; + } + return pList; + +no_mem: + /* Avoid leaking memory if malloc has failed. */ + sqlite3ExprDelete(pExpr); + sqlite3ExprListDelete(pList); + return 0; +} + +/* +** Delete an entire expression list. +*/ +void sqlite3ExprListDelete(ExprList *pList){ + int i; + struct ExprList_item *pItem; + if( pList==0 ) return; + assert( pList->a!=0 || (pList->nExpr==0 && pList->nAlloc==0) ); + assert( pList->nExpr<=pList->nAlloc ); + for(pItem=pList->a, i=0; i<pList->nExpr; i++, pItem++){ + sqlite3ExprDelete(pItem->pExpr); + sqliteFree(pItem->zName); + } + sqliteFree(pList->a); + sqliteFree(pList); +} + +/* +** Walk an expression tree. Call xFunc for each node visited. +** +** The return value from xFunc determines whether the tree walk continues. +** 0 means continue walking the tree. 1 means do not walk children +** of the current node but continue with siblings. 2 means abandon +** the tree walk completely. +** +** The return value from this routine is 1 to abandon the tree walk +** and 0 to continue. +** +** NOTICE: This routine does *not* descend into subqueries. +*/ +static int walkExprList(ExprList *, int (*)(void *, Expr*), void *); +static int walkExprTree(Expr *pExpr, int (*xFunc)(void*,Expr*), void *pArg){ + int rc; + if( pExpr==0 ) return 0; + rc = (*xFunc)(pArg, pExpr); + if( rc==0 ){ + if( walkExprTree(pExpr->pLeft, xFunc, pArg) ) return 1; + if( walkExprTree(pExpr->pRight, xFunc, pArg) ) return 1; + if( walkExprList(pExpr->pList, xFunc, pArg) ) return 1; + } + return rc>1; +} + +/* +** Call walkExprTree() for every expression in list p. +*/ +static int walkExprList(ExprList *p, int (*xFunc)(void *, Expr*), void *pArg){ + int i; + struct ExprList_item *pItem; + if( !p ) return 0; + for(i=p->nExpr, pItem=p->a; i>0; i--, pItem++){ + if( walkExprTree(pItem->pExpr, xFunc, pArg) ) return 1; + } + return 0; +} + +/* +** Call walkExprTree() for every expression in Select p, not including +** expressions that are part of sub-selects in any FROM clause or the LIMIT +** or OFFSET expressions.. +*/ +static int walkSelectExpr(Select *p, int (*xFunc)(void *, Expr*), void *pArg){ + walkExprList(p->pEList, xFunc, pArg); + walkExprTree(p->pWhere, xFunc, pArg); + walkExprList(p->pGroupBy, xFunc, pArg); + walkExprTree(p->pHaving, xFunc, pArg); + walkExprList(p->pOrderBy, xFunc, pArg); + return 0; +} + + +/* +** This routine is designed as an xFunc for walkExprTree(). +** +** pArg is really a pointer to an integer. If we can tell by looking +** at pExpr that the expression that contains pExpr is not a constant +** expression, then set *pArg to 0 and return 2 to abandon the tree walk. +** If pExpr does does not disqualify the expression from being a constant +** then do nothing. +** +** After walking the whole tree, if no nodes are found that disqualify +** the expression as constant, then we assume the whole expression +** is constant. See sqlite3ExprIsConstant() for additional information. +*/ +static int exprNodeIsConstant(void *pArg, Expr *pExpr){ + switch( pExpr->op ){ + /* Consider functions to be constant if all their arguments are constant + ** and *pArg==2 */ + case TK_FUNCTION: + if( *((int*)pArg)==2 ) return 0; + /* Fall through */ + case TK_ID: + case TK_COLUMN: + case TK_DOT: + case TK_AGG_FUNCTION: + case TK_AGG_COLUMN: +#ifndef SQLITE_OMIT_SUBQUERY + case TK_SELECT: + case TK_EXISTS: +#endif + *((int*)pArg) = 0; + return 2; + case TK_IN: + if( pExpr->pSelect ){ + *((int*)pArg) = 0; + return 2; + } + default: + return 0; + } +} + +/* +** Walk an expression tree. Return 1 if the expression is constant +** and 0 if it involves variables or function calls. +** +** For the purposes of this function, a double-quoted string (ex: "abc") +** is considered a variable but a single-quoted string (ex: 'abc') is +** a constant. +*/ +int sqlite3ExprIsConstant(Expr *p){ + int isConst = 1; + walkExprTree(p, exprNodeIsConstant, &isConst); + return isConst; +} + +/* +** Walk an expression tree. Return 1 if the expression is constant +** or a function call with constant arguments. Return and 0 if there +** are any variables. +** +** For the purposes of this function, a double-quoted string (ex: "abc") +** is considered a variable but a single-quoted string (ex: 'abc') is +** a constant. +*/ +int sqlite3ExprIsConstantOrFunction(Expr *p){ + int isConst = 2; + walkExprTree(p, exprNodeIsConstant, &isConst); + return isConst!=0; +} + +/* +** If the expression p codes a constant integer that is small enough +** to fit in a 32-bit integer, return 1 and put the value of the integer +** in *pValue. If the expression is not an integer or if it is too big +** to fit in a signed 32-bit integer, return 0 and leave *pValue unchanged. +*/ +int sqlite3ExprIsInteger(Expr *p, int *pValue){ + switch( p->op ){ + case TK_INTEGER: { + if( sqlite3GetInt32(p->token.z, pValue) ){ + return 1; + } + break; + } + case TK_UPLUS: { + return sqlite3ExprIsInteger(p->pLeft, pValue); + } + case TK_UMINUS: { + int v; + if( sqlite3ExprIsInteger(p->pLeft, &v) ){ + *pValue = -v; + return 1; + } + break; + } + default: break; + } + return 0; +} + +/* +** Return TRUE if the given string is a row-id column name. +*/ +int sqlite3IsRowid(const char *z){ + if( sqlite3StrICmp(z, "_ROWID_")==0 ) return 1; + if( sqlite3StrICmp(z, "ROWID")==0 ) return 1; + if( sqlite3StrICmp(z, "OID")==0 ) return 1; + return 0; +} + +/* +** Given the name of a column of the form X.Y.Z or Y.Z or just Z, look up +** that name in the set of source tables in pSrcList and make the pExpr +** expression node refer back to that source column. The following changes +** are made to pExpr: +** +** pExpr->iDb Set the index in db->aDb[] of the database holding +** the table. +** pExpr->iTable Set to the cursor number for the table obtained +** from pSrcList. +** pExpr->iColumn Set to the column number within the table. +** pExpr->op Set to TK_COLUMN. +** pExpr->pLeft Any expression this points to is deleted +** pExpr->pRight Any expression this points to is deleted. +** +** The pDbToken is the name of the database (the "X"). This value may be +** NULL meaning that name is of the form Y.Z or Z. Any available database +** can be used. The pTableToken is the name of the table (the "Y"). This +** value can be NULL if pDbToken is also NULL. If pTableToken is NULL it +** means that the form of the name is Z and that columns from any table +** can be used. +** +** If the name cannot be resolved unambiguously, leave an error message +** in pParse and return non-zero. Return zero on success. +*/ +static int lookupName( + Parse *pParse, /* The parsing context */ + Token *pDbToken, /* Name of the database containing table, or NULL */ + Token *pTableToken, /* Name of table containing column, or NULL */ + Token *pColumnToken, /* Name of the column. */ + NameContext *pNC, /* The name context used to resolve the name */ + Expr *pExpr /* Make this EXPR node point to the selected column */ +){ + char *zDb = 0; /* Name of the database. The "X" in X.Y.Z */ + char *zTab = 0; /* Name of the table. The "Y" in X.Y.Z or Y.Z */ + char *zCol = 0; /* Name of the column. The "Z" */ + int i, j; /* Loop counters */ + int cnt = 0; /* Number of matching column names */ + int cntTab = 0; /* Number of matching table names */ + sqlite3 *db = pParse->db; /* The database */ + struct SrcList_item *pItem; /* Use for looping over pSrcList items */ + struct SrcList_item *pMatch = 0; /* The matching pSrcList item */ + NameContext *pTopNC = pNC; /* First namecontext in the list */ + + assert( pColumnToken && pColumnToken->z ); /* The Z in X.Y.Z cannot be NULL */ + zDb = sqlite3NameFromToken(pDbToken); + zTab = sqlite3NameFromToken(pTableToken); + zCol = sqlite3NameFromToken(pColumnToken); + if( sqlite3_malloc_failed ){ + goto lookupname_end; + } + + pExpr->iTable = -1; + while( pNC && cnt==0 ){ + SrcList *pSrcList = pNC->pSrcList; + ExprList *pEList = pNC->pEList; + + /* assert( zTab==0 || pEList==0 ); */ + if( pSrcList ){ + for(i=0, pItem=pSrcList->a; i<pSrcList->nSrc; i++, pItem++){ + Table *pTab = pItem->pTab; + Column *pCol; + + if( pTab==0 ) continue; + assert( pTab->nCol>0 ); + if( zTab ){ + if( pItem->zAlias ){ + char *zTabName = pItem->zAlias; + if( sqlite3StrICmp(zTabName, zTab)!=0 ) continue; + }else{ + char *zTabName = pTab->zName; + if( zTabName==0 || sqlite3StrICmp(zTabName, zTab)!=0 ) continue; + if( zDb!=0 && sqlite3StrICmp(db->aDb[pTab->iDb].zName, zDb)!=0 ){ + continue; + } + } + } + if( 0==(cntTab++) ){ + pExpr->iTable = pItem->iCursor; + pExpr->iDb = pTab->iDb; + pMatch = pItem; + } + for(j=0, pCol=pTab->aCol; j<pTab->nCol; j++, pCol++){ + if( sqlite3StrICmp(pCol->zName, zCol)==0 ){ + IdList *pUsing; + cnt++; + pExpr->iTable = pItem->iCursor; + pMatch = pItem; + pExpr->iDb = pTab->iDb; + /* Substitute the rowid (column -1) for the INTEGER PRIMARY KEY */ + pExpr->iColumn = j==pTab->iPKey ? -1 : j; + pExpr->affinity = pTab->aCol[j].affinity; + pExpr->pColl = pTab->aCol[j].pColl; + if( pItem->jointype & JT_NATURAL ){ + /* If this match occurred in the left table of a natural join, + ** then skip the right table to avoid a duplicate match */ + pItem++; + i++; + } + if( (pUsing = pItem->pUsing)!=0 ){ + /* If this match occurs on a column that is in the USING clause + ** of a join, skip the search of the right table of the join + ** to avoid a duplicate match there. */ + int k; + for(k=0; k<pUsing->nId; k++){ + if( sqlite3StrICmp(pUsing->a[k].zName, zCol)==0 ){ + pItem++; + i++; + break; + } + } + } + break; + } + } + } + } + +#ifndef SQLITE_OMIT_TRIGGER + /* If we have not already resolved the name, then maybe + ** it is a new.* or old.* trigger argument reference + */ + if( zDb==0 && zTab!=0 && cnt==0 && pParse->trigStack!=0 ){ + TriggerStack *pTriggerStack = pParse->trigStack; + Table *pTab = 0; + if( pTriggerStack->newIdx != -1 && sqlite3StrICmp("new", zTab) == 0 ){ + pExpr->iTable = pTriggerStack->newIdx; + assert( pTriggerStack->pTab ); + pTab = pTriggerStack->pTab; + }else if( pTriggerStack->oldIdx != -1 && sqlite3StrICmp("old", zTab)==0 ){ + pExpr->iTable = pTriggerStack->oldIdx; + assert( pTriggerStack->pTab ); + pTab = pTriggerStack->pTab; + } + + if( pTab ){ + int j; + Column *pCol = pTab->aCol; + + pExpr->iDb = pTab->iDb; + cntTab++; + for(j=0; j < pTab->nCol; j++, pCol++) { + if( sqlite3StrICmp(pCol->zName, zCol)==0 ){ + cnt++; + pExpr->iColumn = j==pTab->iPKey ? -1 : j; + pExpr->affinity = pTab->aCol[j].affinity; + pExpr->pColl = pTab->aCol[j].pColl; + pExpr->pTab = pTab; + break; + } + } + } + } +#endif /* !defined(SQLITE_OMIT_TRIGGER) */ + + /* + ** Perhaps the name is a reference to the ROWID + */ + if( cnt==0 && cntTab==1 && sqlite3IsRowid(zCol) ){ + cnt = 1; + pExpr->iColumn = -1; + pExpr->affinity = SQLITE_AFF_INTEGER; + } + + /* + ** If the input is of the form Z (not Y.Z or X.Y.Z) then the name Z + ** might refer to an result-set alias. This happens, for example, when + ** we are resolving names in the WHERE clause of the following command: + ** + ** SELECT a+b AS x FROM table WHERE x<10; + ** + ** In cases like this, replace pExpr with a copy of the expression that + ** forms the result set entry ("a+b" in the example) and return immediately. + ** Note that the expression in the result set should have already been + ** resolved by the time the WHERE clause is resolved. + */ + if( cnt==0 && pEList!=0 && zTab==0 ){ + for(j=0; j<pEList->nExpr; j++){ + char *zAs = pEList->a[j].zName; + if( zAs!=0 && sqlite3StrICmp(zAs, zCol)==0 ){ + assert( pExpr->pLeft==0 && pExpr->pRight==0 ); + pExpr->op = TK_AS; + pExpr->iColumn = j; + pExpr->pLeft = sqlite3ExprDup(pEList->a[j].pExpr); + cnt = 1; + assert( zTab==0 && zDb==0 ); + goto lookupname_end_2; + } + } + } + + /* Advance to the next name context. The loop will exit when either + ** we have a match (cnt>0) or when we run out of name contexts. + */ + if( cnt==0 ){ + pNC = pNC->pNext; + } + } + + /* + ** If X and Y are NULL (in other words if only the column name Z is + ** supplied) and the value of Z is enclosed in double-quotes, then + ** Z is a string literal if it doesn't match any column names. In that + ** case, we need to return right away and not make any changes to + ** pExpr. + ** + ** Because no reference was made to outer contexts, the pNC->nRef + ** fields are not changed in any context. + */ + if( cnt==0 && zTab==0 && pColumnToken->z[0]=='"' ){ + sqliteFree(zCol); + return 0; + } + + /* + ** cnt==0 means there was not match. cnt>1 means there were two or + ** more matches. Either way, we have an error. + */ + if( cnt!=1 ){ + char *z = 0; + char *zErr; + zErr = cnt==0 ? "no such column: %s" : "ambiguous column name: %s"; + if( zDb ){ + sqlite3SetString(&z, zDb, ".", zTab, ".", zCol, 0); + }else if( zTab ){ + sqlite3SetString(&z, zTab, ".", zCol, 0); + }else{ + z = sqliteStrDup(zCol); + } + sqlite3ErrorMsg(pParse, zErr, z); + sqliteFree(z); + pTopNC->nErr++; + } + + /* If a column from a table in pSrcList is referenced, then record + ** this fact in the pSrcList.a[].colUsed bitmask. Column 0 causes + ** bit 0 to be set. Column 1 sets bit 1. And so forth. If the + ** column number is greater than the number of bits in the bitmask + ** then set the high-order bit of the bitmask. + */ + if( pExpr->iColumn>=0 && pMatch!=0 ){ + int n = pExpr->iColumn; + if( n>=sizeof(Bitmask)*8 ){ + n = sizeof(Bitmask)*8-1; + } + assert( pMatch->iCursor==pExpr->iTable ); + pMatch->colUsed |= 1<<n; + } + +lookupname_end: + /* Clean up and return + */ + sqliteFree(zDb); + sqliteFree(zTab); + sqlite3ExprDelete(pExpr->pLeft); + pExpr->pLeft = 0; + sqlite3ExprDelete(pExpr->pRight); + pExpr->pRight = 0; + pExpr->op = TK_COLUMN; +lookupname_end_2: + sqliteFree(zCol); + if( cnt==1 ){ + assert( pNC!=0 ); + sqlite3AuthRead(pParse, pExpr, pNC->pSrcList); + if( pMatch && !pMatch->pSelect ){ + pExpr->pTab = pMatch->pTab; + } + /* Increment the nRef value on all name contexts from TopNC up to + ** the point where the name matched. */ + for(;;){ + assert( pTopNC!=0 ); + pTopNC->nRef++; + if( pTopNC==pNC ) break; + pTopNC = pTopNC->pNext; + } + return 0; + } else { + return 1; + } +} + +/* +** This routine is designed as an xFunc for walkExprTree(). +** +** Resolve symbolic names into TK_COLUMN operators for the current +** node in the expression tree. Return 0 to continue the search down +** the tree or 2 to abort the tree walk. +** +** This routine also does error checking and name resolution for +** function names. The operator for aggregate functions is changed +** to TK_AGG_FUNCTION. +*/ +static int nameResolverStep(void *pArg, Expr *pExpr){ + NameContext *pNC = (NameContext*)pArg; + SrcList *pSrcList; + Parse *pParse; + + if( pExpr==0 ) return 1; + assert( pNC!=0 ); + pSrcList = pNC->pSrcList; + pParse = pNC->pParse; + + if( ExprHasAnyProperty(pExpr, EP_Resolved) ) return 1; + ExprSetProperty(pExpr, EP_Resolved); +#ifndef NDEBUG + if( pSrcList ){ + int i; + for(i=0; i<pSrcList->nSrc; i++){ + assert( pSrcList->a[i].iCursor>=0 && pSrcList->a[i].iCursor<pParse->nTab); + } + } +#endif + switch( pExpr->op ){ + /* Double-quoted strings (ex: "abc") are used as identifiers if + ** possible. Otherwise they remain as strings. Single-quoted + ** strings (ex: 'abc') are always string literals. + */ + case TK_STRING: { + if( pExpr->token.z[0]=='\'' ) break; + /* Fall thru into the TK_ID case if this is a double-quoted string */ + } + /* A lone identifier is the name of a column. + */ + case TK_ID: { + lookupName(pParse, 0, 0, &pExpr->token, pNC, pExpr); + return 1; + } + + /* A table name and column name: ID.ID + ** Or a database, table and column: ID.ID.ID + */ + case TK_DOT: { + Token *pColumn; + Token *pTable; + Token *pDb; + Expr *pRight; + + /* if( pSrcList==0 ) break; */ + pRight = pExpr->pRight; + if( pRight->op==TK_ID ){ + pDb = 0; + pTable = &pExpr->pLeft->token; + pColumn = &pRight->token; + }else{ + assert( pRight->op==TK_DOT ); + pDb = &pExpr->pLeft->token; + pTable = &pRight->pLeft->token; + pColumn = &pRight->pRight->token; + } + lookupName(pParse, pDb, pTable, pColumn, pNC, pExpr); + return 1; + } + + /* Resolve function names + */ + case TK_CONST_FUNC: + case TK_FUNCTION: { + ExprList *pList = pExpr->pList; /* The argument list */ + int n = pList ? pList->nExpr : 0; /* Number of arguments */ + int no_such_func = 0; /* True if no such function exists */ + int wrong_num_args = 0; /* True if wrong number of arguments */ + int is_agg = 0; /* True if is an aggregate function */ + int i; + int nId; /* Number of characters in function name */ + const char *zId; /* The function name. */ + FuncDef *pDef; /* Information about the function */ + int enc = pParse->db->enc; /* The database encoding */ + + zId = pExpr->token.z; + nId = pExpr->token.n; + pDef = sqlite3FindFunction(pParse->db, zId, nId, n, enc, 0); + if( pDef==0 ){ + pDef = sqlite3FindFunction(pParse->db, zId, nId, -1, enc, 0); + if( pDef==0 ){ + no_such_func = 1; + }else{ + wrong_num_args = 1; + } + }else{ + is_agg = pDef->xFunc==0; + } + if( is_agg && !pNC->allowAgg ){ + sqlite3ErrorMsg(pParse, "misuse of aggregate function %.*s()", nId,zId); + pNC->nErr++; + is_agg = 0; + }else if( no_such_func ){ + sqlite3ErrorMsg(pParse, "no such function: %.*s", nId, zId); + pNC->nErr++; + }else if( wrong_num_args ){ + sqlite3ErrorMsg(pParse,"wrong number of arguments to function %.*s()", + nId, zId); + pNC->nErr++; + } + if( is_agg ){ + pExpr->op = TK_AGG_FUNCTION; + pNC->hasAgg = 1; + } + if( is_agg ) pNC->allowAgg = 0; + for(i=0; pNC->nErr==0 && i<n; i++){ + walkExprTree(pList->a[i].pExpr, nameResolverStep, pNC); + } + if( is_agg ) pNC->allowAgg = 1; + /* FIX ME: Compute pExpr->affinity based on the expected return + ** type of the function + */ + return is_agg; + } +#ifndef SQLITE_OMIT_SUBQUERY + case TK_SELECT: + case TK_EXISTS: +#endif + case TK_IN: { + if( pExpr->pSelect ){ + int nRef = pNC->nRef; + sqlite3SelectResolve(pParse, pExpr->pSelect, pNC); + assert( pNC->nRef>=nRef ); + if( nRef!=pNC->nRef ){ + ExprSetProperty(pExpr, EP_VarSelect); + } + } + } + } + return 0; +} + +/* +** This routine walks an expression tree and resolves references to +** table columns. Nodes of the form ID.ID or ID resolve into an +** index to the table in the table list and a column offset. The +** Expr.opcode for such nodes is changed to TK_COLUMN. The Expr.iTable +** value is changed to the index of the referenced table in pTabList +** plus the "base" value. The base value will ultimately become the +** VDBE cursor number for a cursor that is pointing into the referenced +** table. The Expr.iColumn value is changed to the index of the column +** of the referenced table. The Expr.iColumn value for the special +** ROWID column is -1. Any INTEGER PRIMARY KEY column is tried as an +** alias for ROWID. +** +** Also resolve function names and check the functions for proper +** usage. Make sure all function names are recognized and all functions +** have the correct number of arguments. Leave an error message +** in pParse->zErrMsg if anything is amiss. Return the number of errors. +** +** If the expression contains aggregate functions then set the EP_Agg +** property on the expression. +*/ +int sqlite3ExprResolveNames( + NameContext *pNC, /* Namespace to resolve expressions in. */ + Expr *pExpr /* The expression to be analyzed. */ +){ + int savedHasAgg; + if( pExpr==0 ) return 0; + savedHasAgg = pNC->hasAgg; + pNC->hasAgg = 0; + walkExprTree(pExpr, nameResolverStep, pNC); + if( pNC->nErr>0 ){ + ExprSetProperty(pExpr, EP_Error); + } + if( pNC->hasAgg ){ + ExprSetProperty(pExpr, EP_Agg); + }else if( savedHasAgg ){ + pNC->hasAgg = 1; + } + return ExprHasProperty(pExpr, EP_Error); +} + +/* +** A pointer instance of this structure is used to pass information +** through walkExprTree into codeSubqueryStep(). +*/ +typedef struct QueryCoder QueryCoder; +struct QueryCoder { + Parse *pParse; /* The parsing context */ + NameContext *pNC; /* Namespace of first enclosing query */ +}; + + +/* +** Generate code for subqueries and IN operators. +** +** IN operators comes in two forms: +** +** expr IN (exprlist) +** and +** expr IN (SELECT ...) +** +** The first form is handled by creating a set holding the list +** of allowed values. The second form causes the SELECT to generate +** a temporary table. +*/ +#ifndef SQLITE_OMIT_SUBQUERY +void sqlite3CodeSubselect(Parse *pParse, Expr *pExpr){ + int testAddr = 0; /* One-time test address */ + Vdbe *v = sqlite3GetVdbe(pParse); + if( v==0 ) return; + + /* This code must be run in its entirety every time it is encountered + ** if any of the following is true: + ** + ** * The right-hand side is a correlated subquery + ** * The right-hand side is an expression list containing variables + ** * We are inside a trigger + ** + ** If all of the above are false, then we can run this code just once + ** save the results, and reuse the same result on subsequent invocations. + */ + if( !ExprHasAnyProperty(pExpr, EP_VarSelect) && !pParse->trigStack ){ + int mem = pParse->nMem++; + sqlite3VdbeAddOp(v, OP_MemLoad, mem, 0); + testAddr = sqlite3VdbeAddOp(v, OP_If, 0, 0); + assert( testAddr>0 || sqlite3_malloc_failed ); + sqlite3VdbeAddOp(v, OP_MemInt, 1, mem); + } + + switch( pExpr->op ){ + case TK_IN: { + char affinity; + KeyInfo keyInfo; + int addr; /* Address of OP_OpenVirtual instruction */ + + affinity = sqlite3ExprAffinity(pExpr->pLeft); + + /* Whether this is an 'x IN(SELECT...)' or an 'x IN(<exprlist>)' + ** expression it is handled the same way. A virtual table is + ** filled with single-field index keys representing the results + ** from the SELECT or the <exprlist>. + ** + ** If the 'x' expression is a column value, or the SELECT... + ** statement returns a column value, then the affinity of that + ** column is used to build the index keys. If both 'x' and the + ** SELECT... statement are columns, then numeric affinity is used + ** if either column has NUMERIC or INTEGER affinity. If neither + ** 'x' nor the SELECT... statement are columns, then numeric affinity + ** is used. + */ + pExpr->iTable = pParse->nTab++; + addr = sqlite3VdbeAddOp(v, OP_OpenVirtual, pExpr->iTable, 0); + memset(&keyInfo, 0, sizeof(keyInfo)); + keyInfo.nField = 1; + sqlite3VdbeAddOp(v, OP_SetNumColumns, pExpr->iTable, 1); + + if( pExpr->pSelect ){ + /* Case 1: expr IN (SELECT ...) + ** + ** Generate code to write the results of the select into the temporary + ** table allocated and opened above. + */ + int iParm = pExpr->iTable + (((int)affinity)<<16); + ExprList *pEList; + assert( (pExpr->iTable&0x0000FFFF)==pExpr->iTable ); + sqlite3Select(pParse, pExpr->pSelect, SRT_Set, iParm, 0, 0, 0, 0); + pEList = pExpr->pSelect->pEList; + if( pEList && pEList->nExpr>0 ){ + keyInfo.aColl[0] = binaryCompareCollSeq(pParse, pExpr->pLeft, + pEList->a[0].pExpr); + } + }else if( pExpr->pList ){ + /* Case 2: expr IN (exprlist) + ** + ** For each expression, build an index key from the evaluation and + ** store it in the temporary table. If <expr> is a column, then use + ** that columns affinity when building index keys. If <expr> is not + ** a column, use numeric affinity. + */ + int i; + ExprList *pList = pExpr->pList; + struct ExprList_item *pItem; + + if( !affinity ){ + affinity = SQLITE_AFF_NUMERIC; + } + keyInfo.aColl[0] = pExpr->pLeft->pColl; + + /* Loop through each expression in <exprlist>. */ + for(i=pList->nExpr, pItem=pList->a; i>0; i--, pItem++){ + Expr *pE2 = pItem->pExpr; + + /* If the expression is not constant then we will need to + ** disable the test that was generated above that makes sure + ** this code only executes once. Because for a non-constant + ** expression we need to rerun this code each time. + */ + if( testAddr>0 && !sqlite3ExprIsConstant(pE2) ){ + VdbeOp *aOp = sqlite3VdbeGetOp(v, testAddr-1); + int i; + for(i=0; i<3; i++){ + aOp[i].opcode = OP_Noop; + } + testAddr = 0; + } + + /* Evaluate the expression and insert it into the temp table */ + sqlite3ExprCode(pParse, pE2); + sqlite3VdbeOp3(v, OP_MakeRecord, 1, 0, &affinity, 1); + sqlite3VdbeAddOp(v, OP_IdxInsert, pExpr->iTable, 0); + } + } + sqlite3VdbeChangeP3(v, addr, (void *)&keyInfo, P3_KEYINFO); + break; + } + + case TK_EXISTS: + case TK_SELECT: { + /* This has to be a scalar SELECT. Generate code to put the + ** value of this select in a memory cell and record the number + ** of the memory cell in iColumn. + */ + int sop; + Select *pSel; + + pExpr->iColumn = pParse->nMem++; + pSel = pExpr->pSelect; + if( pExpr->op==TK_SELECT ){ + sop = SRT_Mem; + }else{ + static const Token one = { "1", 0, 1 }; + sop = SRT_Exists; + sqlite3ExprListDelete(pSel->pEList); + pSel->pEList = sqlite3ExprListAppend(0, + sqlite3Expr(TK_INTEGER, 0, 0, &one), 0); + } + sqlite3Select(pParse, pSel, sop, pExpr->iColumn, 0, 0, 0, 0); + break; + } + } + + if( testAddr ){ + sqlite3VdbeJumpHere(v, testAddr); + } + return; +} +#endif /* SQLITE_OMIT_SUBQUERY */ + +/* +** Generate an instruction that will put the integer describe by +** text z[0..n-1] on the stack. +*/ +static void codeInteger(Vdbe *v, const char *z, int n){ + int i; + if( sqlite3GetInt32(z, &i) ){ + sqlite3VdbeAddOp(v, OP_Integer, i, 0); + }else if( sqlite3FitsIn64Bits(z) ){ + sqlite3VdbeOp3(v, OP_Int64, 0, 0, z, n); + }else{ + sqlite3VdbeOp3(v, OP_Real, 0, 0, z, n); + } +} + +/* +** Generate code into the current Vdbe to evaluate the given +** expression and leave the result on the top of stack. +** +** This code depends on the fact that certain token values (ex: TK_EQ) +** are the same as opcode values (ex: OP_Eq) that implement the corresponding +** operation. Special comments in vdbe.c and the mkopcodeh.awk script in +** the make process cause these values to align. Assert()s in the code +** below verify that the numbers are aligned correctly. +*/ +void sqlite3ExprCode(Parse *pParse, Expr *pExpr){ + Vdbe *v = pParse->pVdbe; + int op; + if( v==0 ) return; + if( pExpr==0 ){ + sqlite3VdbeAddOp(v, OP_Null, 0, 0); + return; + } + op = pExpr->op; + switch( op ){ + case TK_AGG_COLUMN: { + AggInfo *pAggInfo = pExpr->pAggInfo; + struct AggInfo_col *pCol = &pAggInfo->aCol[pExpr->iAgg]; + if( !pAggInfo->directMode ){ + sqlite3VdbeAddOp(v, OP_MemLoad, pCol->iMem, 0); + break; + }else if( pAggInfo->useSortingIdx ){ + sqlite3VdbeAddOp(v, OP_Column, pAggInfo->sortingIdx, + pCol->iSorterColumn); + break; + } + /* Otherwise, fall thru into the TK_COLUMN case */ + } + case TK_COLUMN: { + if( pExpr->iColumn>=0 ){ + sqlite3VdbeAddOp(v, OP_Column, pExpr->iTable, pExpr->iColumn); + sqlite3ColumnDefault(v, pExpr->pTab, pExpr->iColumn); + }else{ + sqlite3VdbeAddOp(v, OP_Rowid, pExpr->iTable, 0); + } + break; + } + case TK_INTEGER: { + codeInteger(v, pExpr->token.z, pExpr->token.n); + break; + } + case TK_FLOAT: + case TK_STRING: { + assert( TK_FLOAT==OP_Real ); + assert( TK_STRING==OP_String8 ); + sqlite3DequoteExpr(pExpr); + sqlite3VdbeOp3(v, op, 0, 0, pExpr->token.z, pExpr->token.n); + break; + } + case TK_NULL: { + sqlite3VdbeAddOp(v, OP_Null, 0, 0); + break; + } +#ifndef SQLITE_OMIT_BLOB_LITERAL + case TK_BLOB: { + int n; + const char *z; + assert( TK_BLOB==OP_HexBlob ); + n = pExpr->token.n - 3; + z = pExpr->token.z + 2; + assert( n>=0 ); + if( n==0 ){ + z = ""; + } + sqlite3VdbeOp3(v, op, 0, 0, z, n); + break; + } +#endif + case TK_VARIABLE: { + sqlite3VdbeAddOp(v, OP_Variable, pExpr->iTable, 0); + if( pExpr->token.n>1 ){ + sqlite3VdbeChangeP3(v, -1, pExpr->token.z, pExpr->token.n); + } + break; + } + case TK_REGISTER: { + sqlite3VdbeAddOp(v, OP_MemLoad, pExpr->iTable, 0); + break; + } +#ifndef SQLITE_OMIT_CAST + case TK_CAST: { + /* Expressions of the form: CAST(pLeft AS token) */ + int aff, op; + sqlite3ExprCode(pParse, pExpr->pLeft); + aff = sqlite3AffinityType(&pExpr->token); + switch( aff ){ + case SQLITE_AFF_INTEGER: op = OP_ToInt; break; + case SQLITE_AFF_NUMERIC: op = OP_ToNumeric; break; + case SQLITE_AFF_TEXT: op = OP_ToText; break; + case SQLITE_AFF_NONE: op = OP_ToBlob; break; + } + sqlite3VdbeAddOp(v, op, 0, 0); + break; + } +#endif /* SQLITE_OMIT_CAST */ + case TK_LT: + case TK_LE: + case TK_GT: + case TK_GE: + case TK_NE: + case TK_EQ: { + assert( TK_LT==OP_Lt ); + assert( TK_LE==OP_Le ); + assert( TK_GT==OP_Gt ); + assert( TK_GE==OP_Ge ); + assert( TK_EQ==OP_Eq ); + assert( TK_NE==OP_Ne ); + sqlite3ExprCode(pParse, pExpr->pLeft); + sqlite3ExprCode(pParse, pExpr->pRight); + codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op, 0, 0); + break; + } + case TK_AND: + case TK_OR: + case TK_PLUS: + case TK_STAR: + case TK_MINUS: + case TK_REM: + case TK_BITAND: + case TK_BITOR: + case TK_SLASH: + case TK_LSHIFT: + case TK_RSHIFT: + case TK_CONCAT: { + assert( TK_AND==OP_And ); + assert( TK_OR==OP_Or ); + assert( TK_PLUS==OP_Add ); + assert( TK_MINUS==OP_Subtract ); + assert( TK_REM==OP_Remainder ); + assert( TK_BITAND==OP_BitAnd ); + assert( TK_BITOR==OP_BitOr ); + assert( TK_SLASH==OP_Divide ); + assert( TK_LSHIFT==OP_ShiftLeft ); + assert( TK_RSHIFT==OP_ShiftRight ); + assert( TK_CONCAT==OP_Concat ); + sqlite3ExprCode(pParse, pExpr->pLeft); + sqlite3ExprCode(pParse, pExpr->pRight); + sqlite3VdbeAddOp(v, op, 0, 0); + break; + } + case TK_UMINUS: { + Expr *pLeft = pExpr->pLeft; + assert( pLeft ); + if( pLeft->op==TK_FLOAT || pLeft->op==TK_INTEGER ){ + Token *p = &pLeft->token; + char *z = sqliteMalloc( p->n + 2 ); + sprintf(z, "-%.*s", p->n, p->z); + if( pLeft->op==TK_FLOAT ){ + sqlite3VdbeOp3(v, OP_Real, 0, 0, z, p->n+1); + }else{ + codeInteger(v, z, p->n+1); + } + sqliteFree(z); + break; + } + /* Fall through into TK_NOT */ + } + case TK_BITNOT: + case TK_NOT: { + assert( TK_BITNOT==OP_BitNot ); + assert( TK_NOT==OP_Not ); + sqlite3ExprCode(pParse, pExpr->pLeft); + sqlite3VdbeAddOp(v, op, 0, 0); + break; + } + case TK_ISNULL: + case TK_NOTNULL: { + int dest; + assert( TK_ISNULL==OP_IsNull ); + assert( TK_NOTNULL==OP_NotNull ); + sqlite3VdbeAddOp(v, OP_Integer, 1, 0); + sqlite3ExprCode(pParse, pExpr->pLeft); + dest = sqlite3VdbeCurrentAddr(v) + 2; + sqlite3VdbeAddOp(v, op, 1, dest); + sqlite3VdbeAddOp(v, OP_AddImm, -1, 0); + break; + } + case TK_AGG_FUNCTION: { + AggInfo *pInfo = pExpr->pAggInfo; + sqlite3VdbeAddOp(v, OP_MemLoad, pInfo->aFunc[pExpr->iAgg].iMem, 0); + break; + } + case TK_CONST_FUNC: + case TK_FUNCTION: { + ExprList *pList = pExpr->pList; + int nExpr = pList ? pList->nExpr : 0; + FuncDef *pDef; + int nId; + const char *zId; + int constMask = 0; + int i; + u8 enc = pParse->db->enc; + CollSeq *pColl = 0; + zId = pExpr->token.z; + nId = pExpr->token.n; + pDef = sqlite3FindFunction(pParse->db, zId, nId, nExpr, enc, 0); + assert( pDef!=0 ); + nExpr = sqlite3ExprCodeExprList(pParse, pList); + for(i=0; i<nExpr && i<32; i++){ + if( sqlite3ExprIsConstant(pList->a[i].pExpr) ){ + constMask |= (1<<i); + } + if( pDef->needCollSeq && !pColl ){ + pColl = sqlite3ExprCollSeq(pParse, pList->a[i].pExpr); + } + } + if( pDef->needCollSeq ){ + if( !pColl ) pColl = pParse->db->pDfltColl; + sqlite3VdbeOp3(v, OP_CollSeq, 0, 0, (char *)pColl, P3_COLLSEQ); + } + sqlite3VdbeOp3(v, OP_Function, constMask, nExpr, (char*)pDef, P3_FUNCDEF); + break; + } +#ifndef SQLITE_OMIT_SUBQUERY + case TK_EXISTS: + case TK_SELECT: { + sqlite3CodeSubselect(pParse, pExpr); + sqlite3VdbeAddOp(v, OP_MemLoad, pExpr->iColumn, 0); + VdbeComment((v, "# load subquery result")); + break; + } + case TK_IN: { + int addr; + char affinity; + sqlite3CodeSubselect(pParse, pExpr); + + /* Figure out the affinity to use to create a key from the results + ** of the expression. affinityStr stores a static string suitable for + ** P3 of OP_MakeRecord. + */ + affinity = comparisonAffinity(pExpr); + + sqlite3VdbeAddOp(v, OP_Integer, 1, 0); + + /* Code the <expr> from "<expr> IN (...)". The temporary table + ** pExpr->iTable contains the values that make up the (...) set. + */ + sqlite3ExprCode(pParse, pExpr->pLeft); + addr = sqlite3VdbeCurrentAddr(v); + sqlite3VdbeAddOp(v, OP_NotNull, -1, addr+4); /* addr + 0 */ + sqlite3VdbeAddOp(v, OP_Pop, 2, 0); + sqlite3VdbeAddOp(v, OP_Null, 0, 0); + sqlite3VdbeAddOp(v, OP_Goto, 0, addr+7); + sqlite3VdbeOp3(v, OP_MakeRecord, 1, 0, &affinity, 1); /* addr + 4 */ + sqlite3VdbeAddOp(v, OP_Found, pExpr->iTable, addr+7); + sqlite3VdbeAddOp(v, OP_AddImm, -1, 0); /* addr + 6 */ + + break; + } +#endif + case TK_BETWEEN: { + Expr *pLeft = pExpr->pLeft; + struct ExprList_item *pLItem = pExpr->pList->a; + Expr *pRight = pLItem->pExpr; + sqlite3ExprCode(pParse, pLeft); + sqlite3VdbeAddOp(v, OP_Dup, 0, 0); + sqlite3ExprCode(pParse, pRight); + codeCompare(pParse, pLeft, pRight, OP_Ge, 0, 0); + sqlite3VdbeAddOp(v, OP_Pull, 1, 0); + pLItem++; + pRight = pLItem->pExpr; + sqlite3ExprCode(pParse, pRight); + codeCompare(pParse, pLeft, pRight, OP_Le, 0, 0); + sqlite3VdbeAddOp(v, OP_And, 0, 0); + break; + } + case TK_UPLUS: + case TK_AS: { + sqlite3ExprCode(pParse, pExpr->pLeft); + break; + } + case TK_CASE: { + int expr_end_label; + int jumpInst; + int nExpr; + int i; + ExprList *pEList; + struct ExprList_item *aListelem; + + assert(pExpr->pList); + assert((pExpr->pList->nExpr % 2) == 0); + assert(pExpr->pList->nExpr > 0); + pEList = pExpr->pList; + aListelem = pEList->a; + nExpr = pEList->nExpr; + expr_end_label = sqlite3VdbeMakeLabel(v); + if( pExpr->pLeft ){ + sqlite3ExprCode(pParse, pExpr->pLeft); + } + for(i=0; i<nExpr; i=i+2){ + sqlite3ExprCode(pParse, aListelem[i].pExpr); + if( pExpr->pLeft ){ + sqlite3VdbeAddOp(v, OP_Dup, 1, 1); + jumpInst = codeCompare(pParse, pExpr->pLeft, aListelem[i].pExpr, + OP_Ne, 0, 1); + sqlite3VdbeAddOp(v, OP_Pop, 1, 0); + }else{ + jumpInst = sqlite3VdbeAddOp(v, OP_IfNot, 1, 0); + } + sqlite3ExprCode(pParse, aListelem[i+1].pExpr); + sqlite3VdbeAddOp(v, OP_Goto, 0, expr_end_label); + sqlite3VdbeJumpHere(v, jumpInst); + } + if( pExpr->pLeft ){ + sqlite3VdbeAddOp(v, OP_Pop, 1, 0); + } + if( pExpr->pRight ){ + sqlite3ExprCode(pParse, pExpr->pRight); + }else{ + sqlite3VdbeAddOp(v, OP_Null, 0, 0); + } + sqlite3VdbeResolveLabel(v, expr_end_label); + break; + } +#ifndef SQLITE_OMIT_TRIGGER + case TK_RAISE: { + if( !pParse->trigStack ){ + sqlite3ErrorMsg(pParse, + "RAISE() may only be used within a trigger-program"); + return; + } + if( pExpr->iColumn!=OE_Ignore ){ + assert( pExpr->iColumn==OE_Rollback || + pExpr->iColumn == OE_Abort || + pExpr->iColumn == OE_Fail ); + sqlite3DequoteExpr(pExpr); + sqlite3VdbeOp3(v, OP_Halt, SQLITE_CONSTRAINT, pExpr->iColumn, + pExpr->token.z, pExpr->token.n); + } else { + assert( pExpr->iColumn == OE_Ignore ); + sqlite3VdbeAddOp(v, OP_ContextPop, 0, 0); + sqlite3VdbeAddOp(v, OP_Goto, 0, pParse->trigStack->ignoreJump); + VdbeComment((v, "# raise(IGNORE)")); + } + } +#endif + break; + } +} + +#ifndef SQLITE_OMIT_TRIGGER +/* +** Generate code that evalutes the given expression and leaves the result +** on the stack. See also sqlite3ExprCode(). +** +** This routine might also cache the result and modify the pExpr tree +** so that it will make use of the cached result on subsequent evaluations +** rather than evaluate the whole expression again. Trivial expressions are +** not cached. If the expression is cached, its result is stored in a +** memory location. +*/ +void sqlite3ExprCodeAndCache(Parse *pParse, Expr *pExpr){ + Vdbe *v = pParse->pVdbe; + int iMem; + int addr1, addr2; + if( v==0 ) return; + addr1 = sqlite3VdbeCurrentAddr(v); + sqlite3ExprCode(pParse, pExpr); + addr2 = sqlite3VdbeCurrentAddr(v); + if( addr2>addr1+1 || sqlite3VdbeGetOp(v, addr1)->opcode==OP_Function ){ + iMem = pExpr->iTable = pParse->nMem++; + sqlite3VdbeAddOp(v, OP_MemStore, iMem, 0); + pExpr->op = TK_REGISTER; + } +} +#endif + +/* +** Generate code that pushes the value of every element of the given +** expression list onto the stack. +** +** Return the number of elements pushed onto the stack. +*/ +int sqlite3ExprCodeExprList( + Parse *pParse, /* Parsing context */ + ExprList *pList /* The expression list to be coded */ +){ + struct ExprList_item *pItem; + int i, n; + if( pList==0 ) return 0; + n = pList->nExpr; + for(pItem=pList->a, i=n; i>0; i--, pItem++){ + sqlite3ExprCode(pParse, pItem->pExpr); + } + return n; +} + +/* +** Generate code for a boolean expression such that a jump is made +** to the label "dest" if the expression is true but execution +** continues straight thru if the expression is false. +** +** If the expression evaluates to NULL (neither true nor false), then +** take the jump if the jumpIfNull flag is true. +** +** This code depends on the fact that certain token values (ex: TK_EQ) +** are the same as opcode values (ex: OP_Eq) that implement the corresponding +** operation. Special comments in vdbe.c and the mkopcodeh.awk script in +** the make process cause these values to align. Assert()s in the code +** below verify that the numbers are aligned correctly. +*/ +void sqlite3ExprIfTrue(Parse *pParse, Expr *pExpr, int dest, int jumpIfNull){ + Vdbe *v = pParse->pVdbe; + int op = 0; + if( v==0 || pExpr==0 ) return; + op = pExpr->op; + switch( op ){ + case TK_AND: { + int d2 = sqlite3VdbeMakeLabel(v); + sqlite3ExprIfFalse(pParse, pExpr->pLeft, d2, !jumpIfNull); + sqlite3ExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull); + sqlite3VdbeResolveLabel(v, d2); + break; + } + case TK_OR: { + sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, jumpIfNull); + sqlite3ExprIfTrue(pParse, pExpr->pRight, dest, jumpIfNull); + break; + } + case TK_NOT: { + sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, jumpIfNull); + break; + } + case TK_LT: + case TK_LE: + case TK_GT: + case TK_GE: + case TK_NE: + case TK_EQ: { + assert( TK_LT==OP_Lt ); + assert( TK_LE==OP_Le ); + assert( TK_GT==OP_Gt ); + assert( TK_GE==OP_Ge ); + assert( TK_EQ==OP_Eq ); + assert( TK_NE==OP_Ne ); + sqlite3ExprCode(pParse, pExpr->pLeft); + sqlite3ExprCode(pParse, pExpr->pRight); + codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op, dest, jumpIfNull); + break; + } + case TK_ISNULL: + case TK_NOTNULL: { + assert( TK_ISNULL==OP_IsNull ); + assert( TK_NOTNULL==OP_NotNull ); + sqlite3ExprCode(pParse, pExpr->pLeft); + sqlite3VdbeAddOp(v, op, 1, dest); + break; + } + case TK_BETWEEN: { + /* The expression "x BETWEEN y AND z" is implemented as: + ** + ** 1 IF (x < y) GOTO 3 + ** 2 IF (x <= z) GOTO <dest> + ** 3 ... + */ + int addr; + Expr *pLeft = pExpr->pLeft; + Expr *pRight = pExpr->pList->a[0].pExpr; + sqlite3ExprCode(pParse, pLeft); + sqlite3VdbeAddOp(v, OP_Dup, 0, 0); + sqlite3ExprCode(pParse, pRight); + addr = codeCompare(pParse, pLeft, pRight, OP_Lt, 0, !jumpIfNull); + + pRight = pExpr->pList->a[1].pExpr; + sqlite3ExprCode(pParse, pRight); + codeCompare(pParse, pLeft, pRight, OP_Le, dest, jumpIfNull); + + sqlite3VdbeAddOp(v, OP_Integer, 0, 0); + sqlite3VdbeJumpHere(v, addr); + sqlite3VdbeAddOp(v, OP_Pop, 1, 0); + break; + } + default: { + sqlite3ExprCode(pParse, pExpr); + sqlite3VdbeAddOp(v, OP_If, jumpIfNull, dest); + break; + } + } +} + +/* +** Generate code for a boolean expression such that a jump is made +** to the label "dest" if the expression is false but execution +** continues straight thru if the expression is true. +** +** If the expression evaluates to NULL (neither true nor false) then +** jump if jumpIfNull is true or fall through if jumpIfNull is false. +*/ +void sqlite3ExprIfFalse(Parse *pParse, Expr *pExpr, int dest, int jumpIfNull){ + Vdbe *v = pParse->pVdbe; + int op = 0; + if( v==0 || pExpr==0 ) return; + + /* The value of pExpr->op and op are related as follows: + ** + ** pExpr->op op + ** --------- ---------- + ** TK_ISNULL OP_NotNull + ** TK_NOTNULL OP_IsNull + ** TK_NE OP_Eq + ** TK_EQ OP_Ne + ** TK_GT OP_Le + ** TK_LE OP_Gt + ** TK_GE OP_Lt + ** TK_LT OP_Ge + ** + ** For other values of pExpr->op, op is undefined and unused. + ** The value of TK_ and OP_ constants are arranged such that we + ** can compute the mapping above using the following expression. + ** Assert()s verify that the computation is correct. + */ + op = ((pExpr->op+(TK_ISNULL&1))^1)-(TK_ISNULL&1); + + /* Verify correct alignment of TK_ and OP_ constants + */ + assert( pExpr->op!=TK_ISNULL || op==OP_NotNull ); + assert( pExpr->op!=TK_NOTNULL || op==OP_IsNull ); + assert( pExpr->op!=TK_NE || op==OP_Eq ); + assert( pExpr->op!=TK_EQ || op==OP_Ne ); + assert( pExpr->op!=TK_LT || op==OP_Ge ); + assert( pExpr->op!=TK_LE || op==OP_Gt ); + assert( pExpr->op!=TK_GT || op==OP_Le ); + assert( pExpr->op!=TK_GE || op==OP_Lt ); + + switch( pExpr->op ){ + case TK_AND: { + sqlite3ExprIfFalse(pParse, pExpr->pLeft, dest, jumpIfNull); + sqlite3ExprIfFalse(pParse, pExpr->pRight, dest, jumpIfNull); + break; + } + case TK_OR: { + int d2 = sqlite3VdbeMakeLabel(v); + sqlite3ExprIfTrue(pParse, pExpr->pLeft, d2, !jumpIfNull); + sqlite3ExprIfFalse(pParse, pExpr->pRight, dest, jumpIfNull); + sqlite3VdbeResolveLabel(v, d2); + break; + } + case TK_NOT: { + sqlite3ExprIfTrue(pParse, pExpr->pLeft, dest, jumpIfNull); + break; + } + case TK_LT: + case TK_LE: + case TK_GT: + case TK_GE: + case TK_NE: + case TK_EQ: { + sqlite3ExprCode(pParse, pExpr->pLeft); + sqlite3ExprCode(pParse, pExpr->pRight); + codeCompare(pParse, pExpr->pLeft, pExpr->pRight, op, dest, jumpIfNull); + break; + } + case TK_ISNULL: + case TK_NOTNULL: { + sqlite3ExprCode(pParse, pExpr->pLeft); + sqlite3VdbeAddOp(v, op, 1, dest); + break; + } + case TK_BETWEEN: { + /* The expression is "x BETWEEN y AND z". It is implemented as: + ** + ** 1 IF (x >= y) GOTO 3 + ** 2 GOTO <dest> + ** 3 IF (x > z) GOTO <dest> + */ + int addr; + Expr *pLeft = pExpr->pLeft; + Expr *pRight = pExpr->pList->a[0].pExpr; + sqlite3ExprCode(pParse, pLeft); + sqlite3VdbeAddOp(v, OP_Dup, 0, 0); + sqlite3ExprCode(pParse, pRight); + addr = sqlite3VdbeCurrentAddr(v); + codeCompare(pParse, pLeft, pRight, OP_Ge, addr+3, !jumpIfNull); + + sqlite3VdbeAddOp(v, OP_Pop, 1, 0); + sqlite3VdbeAddOp(v, OP_Goto, 0, dest); + pRight = pExpr->pList->a[1].pExpr; + sqlite3ExprCode(pParse, pRight); + codeCompare(pParse, pLeft, pRight, OP_Gt, dest, jumpIfNull); + break; + } + default: { + sqlite3ExprCode(pParse, pExpr); + sqlite3VdbeAddOp(v, OP_IfNot, jumpIfNull, dest); + break; + } + } +} + +/* +** Do a deep comparison of two expression trees. Return TRUE (non-zero) +** if they are identical and return FALSE if they differ in any way. +*/ +int sqlite3ExprCompare(Expr *pA, Expr *pB){ + int i; + if( pA==0 ){ + return pB==0; + }else if( pB==0 ){ + return 0; + } + if( pA->op!=pB->op ) return 0; + if( (pA->flags & EP_Distinct)!=(pB->flags & EP_Distinct) ) return 0; + if( !sqlite3ExprCompare(pA->pLeft, pB->pLeft) ) return 0; + if( !sqlite3ExprCompare(pA->pRight, pB->pRight) ) return 0; + if( pA->pList ){ + if( pB->pList==0 ) return 0; + if( pA->pList->nExpr!=pB->pList->nExpr ) return 0; + for(i=0; i<pA->pList->nExpr; i++){ + if( !sqlite3ExprCompare(pA->pList->a[i].pExpr, pB->pList->a[i].pExpr) ){ + return 0; + } + } + }else if( pB->pList ){ + return 0; + } + if( pA->pSelect || pB->pSelect ) return 0; + if( pA->iTable!=pB->iTable || pA->iColumn!=pB->iColumn ) return 0; + if( pA->token.z ){ + if( pB->token.z==0 ) return 0; + if( pB->token.n!=pA->token.n ) return 0; + if( sqlite3StrNICmp(pA->token.z, pB->token.z, pB->token.n)!=0 ) return 0; + } + return 1; +} + + +/* +** Add a new element to the pAggInfo->aCol[] array. Return the index of +** the new element. Return a negative number if malloc fails. +*/ +static int addAggInfoColumn(AggInfo *pInfo){ + int i; + i = sqlite3ArrayAllocate((void**)&pInfo->aCol, sizeof(pInfo->aCol[0]), 3); + if( i<0 ){ + return -1; + } + return i; +} + +/* +** Add a new element to the pAggInfo->aFunc[] array. Return the index of +** the new element. Return a negative number if malloc fails. +*/ +static int addAggInfoFunc(AggInfo *pInfo){ + int i; + i = sqlite3ArrayAllocate((void**)&pInfo->aFunc, sizeof(pInfo->aFunc[0]), 2); + if( i<0 ){ + return -1; + } + return i; +} + +/* +** This is an xFunc for walkExprTree() used to implement +** sqlite3ExprAnalyzeAggregates(). See sqlite3ExprAnalyzeAggregates +** for additional information. +** +** This routine analyzes the aggregate function at pExpr. +*/ +static int analyzeAggregate(void *pArg, Expr *pExpr){ + int i; + NameContext *pNC = (NameContext *)pArg; + Parse *pParse = pNC->pParse; + SrcList *pSrcList = pNC->pSrcList; + AggInfo *pAggInfo = pNC->pAggInfo; + + + switch( pExpr->op ){ + case TK_COLUMN: { + /* Check to see if the column is in one of the tables in the FROM + ** clause of the aggregate query */ + if( pSrcList ){ + struct SrcList_item *pItem = pSrcList->a; + for(i=0; i<pSrcList->nSrc; i++, pItem++){ + struct AggInfo_col *pCol; + if( pExpr->iTable==pItem->iCursor ){ + /* If we reach this point, it means that pExpr refers to a table + ** that is in the FROM clause of the aggregate query. + ** + ** Make an entry for the column in pAggInfo->aCol[] if there + ** is not an entry there already. + */ + pCol = pAggInfo->aCol; + for(i=0; i<pAggInfo->nColumn; i++, pCol++){ + if( pCol->iTable==pExpr->iTable && + pCol->iColumn==pExpr->iColumn ){ + break; + } + } + if( i>=pAggInfo->nColumn && (i = addAggInfoColumn(pAggInfo))>=0 ){ + pCol = &pAggInfo->aCol[i]; + pCol->iTable = pExpr->iTable; + pCol->iColumn = pExpr->iColumn; + pCol->iMem = pParse->nMem++; + pCol->iSorterColumn = -1; + pCol->pExpr = pExpr; + if( pAggInfo->pGroupBy ){ + int j, n; + ExprList *pGB = pAggInfo->pGroupBy; + struct ExprList_item *pTerm = pGB->a; + n = pGB->nExpr; + for(j=0; j<n; j++, pTerm++){ + Expr *pE = pTerm->pExpr; + if( pE->op==TK_COLUMN && pE->iTable==pExpr->iTable && + pE->iColumn==pExpr->iColumn ){ + pCol->iSorterColumn = j; + break; + } + } + } + if( pCol->iSorterColumn<0 ){ + pCol->iSorterColumn = pAggInfo->nSortingColumn++; + } + } + /* There is now an entry for pExpr in pAggInfo->aCol[] (either + ** because it was there before or because we just created it). + ** Convert the pExpr to be a TK_AGG_COLUMN referring to that + ** pAggInfo->aCol[] entry. + */ + pExpr->pAggInfo = pAggInfo; + pExpr->op = TK_AGG_COLUMN; + pExpr->iAgg = i; + break; + } /* endif pExpr->iTable==pItem->iCursor */ + } /* end loop over pSrcList */ + } + return 1; + } + case TK_AGG_FUNCTION: { + /* The pNC->nDepth==0 test causes aggregate functions in subqueries + ** to be ignored */ + if( pNC->nDepth==0 ){ + /* Check to see if pExpr is a duplicate of another aggregate + ** function that is already in the pAggInfo structure + */ + struct AggInfo_func *pItem = pAggInfo->aFunc; + for(i=0; i<pAggInfo->nFunc; i++, pItem++){ + if( sqlite3ExprCompare(pItem->pExpr, pExpr) ){ + break; + } + } + if( i>=pAggInfo->nFunc ){ + /* pExpr is original. Make a new entry in pAggInfo->aFunc[] + */ + u8 enc = pParse->db->enc; + i = addAggInfoFunc(pAggInfo); + if( i>=0 ){ + pItem = &pAggInfo->aFunc[i]; + pItem->pExpr = pExpr; + pItem->iMem = pParse->nMem++; + pItem->pFunc = sqlite3FindFunction(pParse->db, + pExpr->token.z, pExpr->token.n, + pExpr->pList ? pExpr->pList->nExpr : 0, enc, 0); + if( pExpr->flags & EP_Distinct ){ + pItem->iDistinct = pParse->nTab++; + }else{ + pItem->iDistinct = -1; + } + } + } + /* Make pExpr point to the appropriate pAggInfo->aFunc[] entry + */ + pExpr->iAgg = i; + pExpr->pAggInfo = pAggInfo; + return 1; + } + } + } + + /* Recursively walk subqueries looking for TK_COLUMN nodes that need + ** to be changed to TK_AGG_COLUMN. But increment nDepth so that + ** TK_AGG_FUNCTION nodes in subqueries will be unchanged. + */ + if( pExpr->pSelect ){ + pNC->nDepth++; + walkSelectExpr(pExpr->pSelect, analyzeAggregate, pNC); + pNC->nDepth--; + } + return 0; +} + +/* +** Analyze the given expression looking for aggregate functions and +** for variables that need to be added to the pParse->aAgg[] array. +** Make additional entries to the pParse->aAgg[] array as necessary. +** +** This routine should only be called after the expression has been +** analyzed by sqlite3ExprResolveNames(). +** +** If errors are seen, leave an error message in zErrMsg and return +** the number of errors. +*/ +int sqlite3ExprAnalyzeAggregates(NameContext *pNC, Expr *pExpr){ + int nErr = pNC->pParse->nErr; + walkExprTree(pExpr, analyzeAggregate, pNC); + return pNC->pParse->nErr - nErr; +} + +/* +** Call sqlite3ExprAnalyzeAggregates() for every expression in an +** expression list. Return the number of errors. +** +** If an error is found, the analysis is cut short. +*/ +int sqlite3ExprAnalyzeAggList(NameContext *pNC, ExprList *pList){ + struct ExprList_item *pItem; + int i; + int nErr = 0; + if( pList ){ + for(pItem=pList->a, i=0; nErr==0 && i<pList->nExpr; i++, pItem++){ + nErr += sqlite3ExprAnalyzeAggregates(pNC, pItem->pExpr); + } + } + return nErr; +} |