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-rw-r--r--src/expr.c143
-rw-r--r--src/resolve.c7
-rw-r--r--src/sqliteInt.h4
3 files changed, 96 insertions, 58 deletions
diff --git a/src/expr.c b/src/expr.c
index 61e84e56b..62d2691bc 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -5879,81 +5879,109 @@ int sqlite3ExprCoveredByIndex(
}
-/*
-** 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
-** sqlite3FunctionThisSrc() routine.
-*/
-struct SrcCount {
- SrcList *pSrc; /* One particular FROM clause in a nested query */
- int iSrcInner; /* Smallest cursor number in this context */
- int nThis; /* Number of references to columns in pSrcList */
- int nOther; /* Number of references to columns in other FROM clauses */
+/* Structure used to pass information throught the Walker in order to
+** implement sqlite3ReferencesSrcList().
+*/
+struct RefSrcList {
+ sqlite3 *db; /* Database connection used for sqlite3DbRealloc() */
+ SrcList *pRef; /* Looking for references to these tables */
+ int nExclude; /* Number of tables to exclude from the search */
+ int *aiExclude; /* Cursor IDs for tables to exclude from the search */
};
/*
-** xSelect callback for sqlite3FunctionUsesThisSrc(). If this is the first
-** SELECT with a FROM clause encountered during this iteration, set
-** SrcCount.iSrcInner to the cursor number of the leftmost object in
-** the FROM cause.
+** Walker SELECT callbacks for sqlite3ReferencesSrcList().
+**
+** When entering a new subquery on the pExpr argument, add all FROM clause
+** entries for that subquery to the exclude list.
+**
+** When leaving the subquery, remove those entries from the exclude list.
*/
-static int selectSrcCount(Walker *pWalker, Select *pSel){
- struct SrcCount *p = pWalker->u.pSrcCount;
- if( p->iSrcInner==0x7FFFFFFF && ALWAYS(pSel->pSrc) && pSel->pSrc->nSrc ){
- pWalker->u.pSrcCount->iSrcInner = pSel->pSrc->a[0].iCursor;
+static int selectRefEnter(Walker *pWalker, Select *pSelect){
+ struct RefSrcList *p = pWalker->u.pRefSrcList;
+ SrcList *pSrc = pSelect->pSrc;
+ int i, j, *piNew;
+ if( pSrc->nSrc==0 ) return WRC_Continue;
+ j = p->nExclude;
+ p->nExclude += pSrc->nSrc;
+ piNew = sqlite3DbRealloc(p->db, p->aiExclude, p->nExclude*sizeof(int));
+ if( piNew==0 ){
+ p->nExclude = 0;
+ return WRC_Abort;
+ }else{
+ p->aiExclude = piNew;
+ }
+ for(i=0; i<pSrc->nSrc; i++, j++){
+ p->aiExclude[j] = pSrc->a[i].iCursor;
}
return WRC_Continue;
}
+static void selectRefLeave(Walker *pWalker, Select *pSelect){
+ struct RefSrcList *p = pWalker->u.pRefSrcList;
+ SrcList *pSrc = pSelect->pSrc;
+ if( p->nExclude ){
+ assert( p->nExclude>=pSrc->nSrc );
+ p->nExclude -= pSrc->nSrc;
+ }
+}
-/*
-** Count the number of references to columns.
+/* This is the Walker EXPR callback for sqlite3ReferencesSrcList().
+**
+** Set the 0x01 bit of pWalker->eCode if there is a reference to any
+** of the tables shown in RefSrcList.pRef.
+**
+** Set the 0x02 bit of pWalker->eCode if there is a reference to a
+** table is in neither RefSrcList.pRef nor RefSrcList.aiExclude.
*/
-static int exprSrcCount(Walker *pWalker, Expr *pExpr){
- /* There was once a NEVER() on the second term on the grounds that
- ** sqlite3FunctionUsesThisSrc() was always called before
- ** sqlite3ExprAnalyzeAggregates() and so the TK_COLUMNs have not yet
- ** been converted into TK_AGG_COLUMN. But this is no longer true due
- ** to window functions - sqlite3WindowRewrite() may now indirectly call
- ** FunctionUsesThisSrc() when creating a new sub-select. */
- if( pExpr->op==TK_COLUMN || pExpr->op==TK_AGG_COLUMN ){
+static int exprRefToSrcList(Walker *pWalker, Expr *pExpr){
+ if( pExpr->op==TK_COLUMN
+ || pExpr->op==TK_AGG_COLUMN
+ ){
int i;
- struct SrcCount *p = pWalker->u.pSrcCount;
- SrcList *pSrc = p->pSrc;
+ struct RefSrcList *p = pWalker->u.pRefSrcList;
+ SrcList *pSrc = p->pRef;
int nSrc = pSrc ? pSrc->nSrc : 0;
for(i=0; i<nSrc; i++){
- if( pExpr->iTable==pSrc->a[i].iCursor ) break;
+ if( pExpr->iTable==pSrc->a[i].iCursor ){
+ pWalker->eCode |= 1;
+ return WRC_Continue;
+ }
}
- if( i<nSrc ){
- p->nThis++;
- }else if( pExpr->iTable<p->iSrcInner ){
- /* In a well-formed parse tree (no name resolution errors),
- ** TK_COLUMN nodes with smaller Expr.iTable values are in an
- ** outer context. Those are the only ones to count as "other" */
- p->nOther++;
+ for(i=0; i<p->nExclude && p->aiExclude[i]!=pExpr->iTable; i++){}
+ if( i>=p->nExclude ){
+ pWalker->eCode |= 2;
}
}
return WRC_Continue;
}
/*
-** 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.
+** Check to see if pExpr references any tables in pSrcList.
+** Possible return values:
+**
+** 1 pExpr does references a table in pSrcList.
+**
+** 0 pExpr references some table that is not defined in either
+** pSrcList or in subqueries of pExpr itself.
+**
+** -1 pExpr only references no tables at all, or it only
+** references tables defined in subqueries of pExpr itself.
+**
+** As currently used, pExpr is always an aggregate function call. That
+** fact is exploited for efficiency.
*/
-int sqlite3FunctionUsesThisSrc(Expr *pExpr, SrcList *pSrcList){
+int sqlite3ReferencesSrcList(Parse *pParse, Expr *pExpr, SrcList *pSrcList){
Walker w;
- struct SrcCount cnt;
- assert( pExpr->op==TK_AGG_FUNCTION );
+ struct RefSrcList x;
memset(&w, 0, sizeof(w));
- w.xExprCallback = exprSrcCount;
- w.xSelectCallback = selectSrcCount;
- w.u.pSrcCount = &cnt;
- cnt.pSrc = pSrcList;
- cnt.iSrcInner = (pSrcList&&pSrcList->nSrc)?pSrcList->a[0].iCursor:0x7FFFFFFF;
- cnt.nThis = 0;
- cnt.nOther = 0;
+ memset(&x, 0, sizeof(x));
+ w.xExprCallback = exprRefToSrcList;
+ w.xSelectCallback = selectRefEnter;
+ w.xSelectCallback2 = selectRefLeave;
+ w.u.pRefSrcList = &x;
+ x.db = pParse->db;
+ x.pRef = pSrcList;
+ assert( pExpr->op==TK_AGG_FUNCTION );
assert( ExprUseXList(pExpr) );
sqlite3WalkExprList(&w, pExpr->x.pList);
#ifndef SQLITE_OMIT_WINDOWFUNC
@@ -5961,7 +5989,14 @@ int sqlite3FunctionUsesThisSrc(Expr *pExpr, SrcList *pSrcList){
sqlite3WalkExpr(&w, pExpr->y.pWin->pFilter);
}
#endif
- return cnt.nThis>0 || cnt.nOther==0;
+ sqlite3DbFree(pParse->db, x.aiExclude);
+ if( w.eCode & 0x01 ){
+ return 1;
+ }else if( w.eCode ){
+ return 0;
+ }else{
+ return -1;
+ }
}
/*
diff --git a/src/resolve.c b/src/resolve.c
index c55fc514c..27b260e05 100644
--- a/src/resolve.c
+++ b/src/resolve.c
@@ -1092,7 +1092,7 @@ static int resolveExprStep(Walker *pWalker, Expr *pExpr){
}else
#endif /* SQLITE_OMIT_WINDOWFUNC */
{
- NameContext *pNC2 = pNC;
+ NameContext *pNC2; /* For looping up thru outer contexts */
pExpr->op = TK_AGG_FUNCTION;
pExpr->op2 = 0;
#ifndef SQLITE_OMIT_WINDOWFUNC
@@ -1100,7 +1100,10 @@ static int resolveExprStep(Walker *pWalker, Expr *pExpr){
sqlite3WalkExpr(pWalker, pExpr->y.pWin->pFilter);
}
#endif
- while( pNC2 && !sqlite3FunctionUsesThisSrc(pExpr, pNC2->pSrcList) ){
+ pNC2 = pNC;
+ while( pNC2
+ && sqlite3ReferencesSrcList(pParse, pExpr, pNC2->pSrcList)==0
+ ){
pExpr->op2++;
pNC2 = pNC2->pNext;
}
diff --git a/src/sqliteInt.h b/src/sqliteInt.h
index 984b3c680..75f3bfca2 100644
--- a/src/sqliteInt.h
+++ b/src/sqliteInt.h
@@ -3964,8 +3964,8 @@ struct Walker {
int n; /* A counter */
int iCur; /* A cursor number */
SrcList *pSrcList; /* FROM clause */
- struct SrcCount *pSrcCount; /* Counting column references */
struct CCurHint *pCCurHint; /* Used by codeCursorHint() */
+ struct RefSrcList *pRefSrcList; /* sqlite3ReferencesSrcList() */
int *aiCol; /* array of column indexes */
struct IdxCover *pIdxCover; /* Check for index coverage */
struct IdxExprTrans *pIdxTrans; /* Convert idxed expr to column */
@@ -4623,7 +4623,7 @@ void sqlite3AggInfoPersistWalkerInit(Walker*,Parse*);
void sqlite3ExprAnalyzeAggregates(NameContext*, Expr*);
void sqlite3ExprAnalyzeAggList(NameContext*,ExprList*);
int sqlite3ExprCoveredByIndex(Expr*, int iCur, Index *pIdx);
-int sqlite3FunctionUsesThisSrc(Expr*, SrcList*);
+int sqlite3ReferencesSrcList(Parse*, Expr*, SrcList*);
Vdbe *sqlite3GetVdbe(Parse*);
#ifndef SQLITE_UNTESTABLE
void sqlite3PrngSaveState(void);
generated by cgit v1.2.3 (git 2.25.1) at 2025-07-18 05:38:14 +0000