diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/expr.c | 65 | ||||
| -rw-r--r-- | src/resolve.c | 14 | ||||
| -rw-r--r-- | src/select.c | 5 | ||||
| -rw-r--r-- | src/sqliteInt.h | 8 |
4 files changed, 70 insertions, 22 deletions
diff --git a/src/expr.c b/src/expr.c index 790aa45f3..e2f8b4578 100644 --- a/src/expr.c +++ b/src/expr.c @@ -3816,22 +3816,35 @@ int sqlite3ExprListCompare(ExprList *pA, ExprList *pB){ } /* -** This is the expression callback for sqlite3FunctionUsesOtherSrc(). -** -** Determine if an expression references any table other than one of the -** tables in pWalker->u.pSrcList and abort if it does. +** An instance of the following structure is used by the tree walker +** to count references to table columns in the arguments of an +** aggregate function, in order to implement the sqlite3FunctionUsesOtherSrc() +** and sqlite3FunctionThisSrc() routines. */ -static int exprUsesOtherSrc(Walker *pWalker, Expr *pExpr){ +struct SrcCount { + SrcList *pSrc; /* One particular FROM clause in a nested query */ + int nThis; /* Number of references to columns in pSrcList */ + int nOther; /* Number of references to columns in other FROM clauses */ +}; + +/* +** Count the number of references to columns. +*/ +static int exprSrcCount(Walker *pWalker, Expr *pExpr){ if( pExpr->op==TK_COLUMN || pExpr->op==TK_AGG_COLUMN ){ int i; - SrcList *pSrc = pWalker->u.pSrcList; + struct SrcCount *p = pWalker->u.pSrcCount; + SrcList *pSrc = p->pSrc; for(i=0; i<pSrc->nSrc; i++){ - if( pExpr->iTable==pSrc->a[i].iCursor ) return WRC_Continue; + if( pExpr->iTable==pSrc->a[i].iCursor ) break; + } + if( i<pSrc->nSrc ){ + p->nThis++; + }else{ + p->nOther++; } - return WRC_Abort; - }else{ - return WRC_Continue; } + return WRC_Continue; } /* @@ -3842,12 +3855,36 @@ static int exprUsesOtherSrc(Walker *pWalker, Expr *pExpr){ */ static int sqlite3FunctionUsesOtherSrc(Expr *pExpr, SrcList *pSrcList){ Walker w; + struct SrcCount cnt; assert( pExpr->op==TK_AGG_FUNCTION ); memset(&w, 0, sizeof(w)); - w.xExprCallback = exprUsesOtherSrc; - w.u.pSrcList = pSrcList; - if( sqlite3WalkExprList(&w, pExpr->x.pList)!=WRC_Continue ) return 1; - return 0; + w.xExprCallback = exprSrcCount; + w.u.pSrcCount = &cnt; + cnt.pSrc = pSrcList; + cnt.nThis = 0; + cnt.nOther = 0; + sqlite3WalkExprList(&w, pExpr->x.pList); + return cnt.nOther>0; +} + +/* +** Determine if any of the arguments to the pExpr Function reference +** pSrcList. Return true if they do. Also return true if the function +** has no arguments or has only constant arguments. Return false if pExpr +** references columns but not columns of tables found in pSrcList. +*/ +int sqlite3FunctionUsesThisSrc(Expr *pExpr, SrcList *pSrcList){ + Walker w; + struct SrcCount cnt; + assert( pExpr->op==TK_AGG_FUNCTION ); + memset(&w, 0, sizeof(w)); + w.xExprCallback = exprSrcCount; + w.u.pSrcCount = &cnt; + cnt.pSrc = pSrcList; + cnt.nThis = 0; + cnt.nOther = 0; + sqlite3WalkExprList(&w, pExpr->x.pList); + return cnt.nThis>0 || cnt.nOther==0; } /* diff --git a/src/resolve.c b/src/resolve.c index a66f88fdc..bfbcd2041 100644 --- a/src/resolve.c +++ b/src/resolve.c @@ -568,13 +568,19 @@ static int resolveExprStep(Walker *pWalker, Expr *pExpr){ nId, zId); pNC->nErr++; } + if( is_agg ) pNC->ncFlags &= ~NC_AllowAgg; + sqlite3WalkExprList(pWalker, pList); if( is_agg ){ + NameContext *pNC2 = pNC; pExpr->op = TK_AGG_FUNCTION; - pNC->ncFlags |= NC_HasAgg; + pExpr->op2 = 0; + while( pNC2 && !sqlite3FunctionUsesThisSrc(pExpr, pNC2->pSrcList) ){ + pExpr->op2++; + pNC2 = pNC2->pNext; + } + if( pNC2 ) pNC2->ncFlags |= NC_HasAgg; + pNC->ncFlags |= NC_AllowAgg; } - if( is_agg ) pNC->ncFlags &= ~NC_AllowAgg; - sqlite3WalkExprList(pWalker, pList); - if( is_agg ) pNC->ncFlags |= NC_AllowAgg; /* FIX ME: Compute pExpr->affinity based on the expected return ** type of the function */ diff --git a/src/select.c b/src/select.c index 491356acb..93a084eaf 100644 --- a/src/select.c +++ b/src/select.c @@ -3521,7 +3521,7 @@ static void sqlite3SelectAddTypeInfo(Parse *pParse, Select *pSelect){ /* -** This routine sets of a SELECT statement for processing. The +** This routine sets up a SELECT statement for processing. The ** following is accomplished: ** ** * VDBE Cursor numbers are assigned to all FROM-clause terms. @@ -3553,7 +3553,8 @@ void sqlite3SelectPrep( ** ** The aggregate accumulator is a set of memory cells that hold ** intermediate results while calculating an aggregate. This -** routine simply stores NULLs in all of those memory cells. +** routine generates code that stores NULLs in all of those memory +** cells. */ static void resetAccumulator(Parse *pParse, AggInfo *pAggInfo){ Vdbe *v = pParse->pVdbe; diff --git a/src/sqliteInt.h b/src/sqliteInt.h index b3cdb2363..443eaa403 100644 --- a/src/sqliteInt.h +++ b/src/sqliteInt.h @@ -1690,8 +1690,9 @@ struct Expr { i16 iAgg; /* Which entry in pAggInfo->aCol[] or ->aFunc[] */ i16 iRightJoinTable; /* If EP_FromJoin, the right table of the join */ u8 flags2; /* Second set of flags. EP2_... */ - u8 op2; /* If a TK_REGISTER, the original value of Expr.op */ - /* If TK_COLUMN, the value of p5 for OP_Column */ + u8 op2; /* TK_REGISTER: original value of Expr.op + ** TK_COLUMN: the value of p5 for OP_Column + ** TK_AGG_FUNCTION: nesting depth */ AggInfo *pAggInfo; /* Used by TK_AGG_COLUMN and TK_AGG_FUNCTION */ Table *pTab; /* Table for TK_COLUMN expressions. */ #if SQLITE_MAX_EXPR_DEPTH>0 @@ -2498,10 +2499,12 @@ struct Walker { int (*xExprCallback)(Walker*, Expr*); /* Callback for expressions */ int (*xSelectCallback)(Walker*,Select*); /* Callback for SELECTs */ Parse *pParse; /* Parser context. */ + int walkerDepth; /* Number of subqueries */ union { /* Extra data for callback */ NameContext *pNC; /* Naming context */ int i; /* Integer value */ SrcList *pSrcList; /* FROM clause */ + struct SrcCount *pSrcCount; /* Counting column references */ } u; }; @@ -2835,6 +2838,7 @@ int sqlite3ExprCompare(Expr*, Expr*); int sqlite3ExprListCompare(ExprList*, ExprList*); void sqlite3ExprAnalyzeAggregates(NameContext*, Expr*); void sqlite3ExprAnalyzeAggList(NameContext*,ExprList*); +int sqlite3FunctionUsesThisSrc(Expr*, SrcList*); Vdbe *sqlite3GetVdbe(Parse*); void sqlite3PrngSaveState(void); void sqlite3PrngRestoreState(void); |