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-rw-r--r--src/select.c96
1 files changed, 51 insertions, 45 deletions
diff --git a/src/select.c b/src/select.c
index 4a37a1acb..2176a6285 100644
--- a/src/select.c
+++ b/src/select.c
@@ -4840,16 +4840,16 @@ static struct Cte *searchWith(
struct SrcList_item *pItem, /* FROM clause element to resolve */
With **ppContext /* OUT: WITH clause return value belongs to */
){
- const char *zName;
- if( pItem->zDatabase==0 && (zName = pItem->zName)!=0 ){
- With *p;
- for(p=pWith; p; p=p->pOuter){
- int i;
- for(i=0; i<p->nCte; i++){
- if( sqlite3StrICmp(zName, p->a[i].zName)==0 ){
- *ppContext = p;
- return &p->a[i];
- }
+ const char *zName = pItem->zName;
+ With *p;
+ assert( pItem->zDatabase==0 );
+ assert( zName!=0 );
+ for(p=pWith; p; p=p->pOuter){
+ int i;
+ for(i=0; i<p->nCte; i++){
+ if( sqlite3StrICmp(zName, p->a[i].zName)==0 ){
+ *ppContext = p;
+ return &p->a[i];
}
}
}
@@ -4882,35 +4882,39 @@ void sqlite3WithPush(Parse *pParse, With *pWith, u8 bFree){
/*
** This function checks if argument pFrom refers to a CTE declared by
-** a WITH clause on the stack currently maintained by the parser. And,
-** if currently processing a CTE expression, if it is a recursive
-** reference to the current CTE.
-**
-** If pFrom falls into either of the two categories above, pFrom->pTab
-** and other fields are populated accordingly. The caller should check
-** (pFrom->pTab!=0) to determine whether or not a successful match
-** was found.
-**
-** Whether or not a match is found, SQLITE_OK is returned if no error
-** occurs. If an error does occur, an error message is stored in the
-** parser and some error code other than SQLITE_OK returned.
+** a WITH clause on the stack currently maintained by the parser (on the
+** pParse->pWith linked list). And if currently processing a CTE
+** CTE expression, through routine checks to see if the reference is
+** a recursive reference to the CTE.
+**
+** If pFrom matches a CTE according to either of these two above, pFrom->pTab
+** and other fields are populated accordingly.
+**
+** Return 0 if no match is found.
+** Return 1 if a match is found.
+** Return 2 if an error condition is detected.
*/
-static int withExpand(
- Walker *pWalker,
- struct SrcList_item *pFrom
+static int resolveFromTermToCte(
+ Parse *pParse, /* The parsing context */
+ Walker *pWalker, /* Current tree walker */
+ struct SrcList_item *pFrom /* The FROM clause term to check */
){
- Parse *pParse = pWalker->pParse;
- sqlite3 *db = pParse->db;
- struct Cte *pCte; /* Matched CTE (or NULL if no match) */
- With *pWith; /* WITH clause that pCte belongs to */
+ Cte *pCte; /* Matched CTE (or NULL if no match) */
+ With *pWith; /* The matching WITH */
assert( pFrom->pTab==0 );
- if( pParse->nErr ){
- return SQLITE_ERROR;
+ if( pParse->pWith==0 ){
+ /* There are no WITH clauses in the stack. No match is possible */
+ return 0;
+ }
+ if( pFrom->zDatabase!=0 ){
+ /* The FROM term contains a schema qualifier (ex: main.t1) and so
+ ** it cannot possibly be a CTE reference. */
+ return 0;
}
-
pCte = searchWith(pParse->pWith, pFrom, &pWith);
if( pCte ){
+ sqlite3 *db = pParse->db;
Table *pTab;
ExprList *pEList;
Select *pSel;
@@ -4926,20 +4930,20 @@ static int withExpand(
** In this case, proceed. */
if( pCte->zCteErr ){
sqlite3ErrorMsg(pParse, pCte->zCteErr, pCte->zName);
- return SQLITE_ERROR;
+ return 2;
}
- if( cannotBeFunction(pParse, pFrom) ) return SQLITE_ERROR;
+ if( cannotBeFunction(pParse, pFrom) ) return 2;
assert( pFrom->pTab==0 );
pFrom->pTab = pTab = sqlite3DbMallocZero(db, sizeof(Table));
- if( pTab==0 ) return WRC_Abort;
+ if( pTab==0 ) return 2;
pTab->nTabRef = 1;
pTab->zName = sqlite3DbStrDup(db, pCte->zName);
pTab->iPKey = -1;
pTab->nRowLogEst = 200; assert( 200==sqlite3LogEst(1048576) );
pTab->tabFlags |= TF_Ephemeral | TF_NoVisibleRowid;
pFrom->pSelect = sqlite3SelectDup(db, pCte->pSelect, 0);
- if( db->mallocFailed ) return SQLITE_NOMEM_BKPT;
+ if( db->mallocFailed ) return 2;
assert( pFrom->pSelect );
/* Check if this is a recursive CTE. */
@@ -4962,7 +4966,7 @@ static int withExpand(
sqlite3ErrorMsg(pParse,
"multiple references to recursive table: %s", pCte->zName
);
- return SQLITE_ERROR;
+ return 2;
}
pRecTerm->selFlags |= SF_Recursive;
if( iRecTab<0 ) iRecTab = pParse->nTab++;
@@ -4998,7 +5002,7 @@ static int withExpand(
pCte->zName, pEList->nExpr, pCte->pCols->nExpr
);
pParse->pWith = pSavedWith;
- return SQLITE_ERROR;
+ return 2;
}
pEList = pCte->pCols;
}
@@ -5014,9 +5018,9 @@ static int withExpand(
}
pCte->zCteErr = 0;
pParse->pWith = pSavedWith;
+ return 1; /* Success */
}
-
- return SQLITE_OK;
+ return 0; /* No match */
}
#endif
@@ -5098,7 +5102,7 @@ int sqlite3ExpandSubquery(Parse *pParse, struct SrcList_item *pFrom){
*/
static int selectExpander(Walker *pWalker, Select *p){
Parse *pParse = pWalker->pParse;
- int i, j, k;
+ int i, j, k, rc;
SrcList *pTabList;
ExprList *pEList;
struct SrcList_item *pFrom;
@@ -5137,10 +5141,6 @@ static int selectExpander(Walker *pWalker, Select *p){
assert( pFrom->fg.isRecursive==0 || pFrom->pTab!=0 );
if( pFrom->pTab ) continue;
assert( pFrom->fg.isRecursive==0 );
-#ifndef SQLITE_OMIT_CTE
- if( withExpand(pWalker, pFrom) ) return WRC_Abort;
- if( pFrom->pTab ) {} else
-#endif
if( pFrom->zName==0 ){
#ifndef SQLITE_OMIT_SUBQUERY
Select *pSel = pFrom->pSelect;
@@ -5150,6 +5150,12 @@ static int selectExpander(Walker *pWalker, Select *p){
if( sqlite3WalkSelect(pWalker, pSel) ) return WRC_Abort;
if( sqlite3ExpandSubquery(pParse, pFrom) ) return WRC_Abort;
#endif
+#ifndef SQLITE_OMIT_CTE
+ }else if( (rc = resolveFromTermToCte(pParse, pWalker, pFrom))!=0 ){
+ if( rc>1 ) return WRC_Abort;
+ pTab = pFrom->pTab;
+ assert( pTab!=0 );
+#endif
}else{
/* An ordinary table or view name in the FROM clause */
assert( pFrom->pTab==0 );
generated by cgit v1.2.3 (git 2.25.1) at 2025-07-19 16:35:58 +0000