Fix for tickets #32 and #33: Generate the names of the result set early, before

doing the flattening optimization or evaluating subqueries.  Otherwise, the
result set column names are generated incorrectly or after they are needed. (CVS 553)

FossilOrigin-Name: 08f27cb36805d38648274b6fe91dec43a5910057

1 files changed, 22 insertions, 22 deletions

diff --git a/src/select.c b/src/select.c
index 530a7a3dd..7038809ce 100644
--- a/src/select.c
+++ b/src/select.c
@@ -12,7 +12,7 @@
 ** This file contains C code routines that are called by the parser
 ** to handle SELECT statements in SQLite.
 **
-** $Id: select.c,v 1.80 2002/04/30 19:20:29 drh Exp $
+** $Id: select.c,v 1.81 2002/05/08 11:54:15 drh Exp $
 */
 #include "sqliteInt.h"
 
@@ -931,9 +931,10 @@ substExprList(ExprList *pList, int iTable, ExprList *pEList, int iSub){
 ** the subquery before this routine runs.
 */
 int flattenSubquery(Select *p, int iFrom, int isAgg, int subqueryIsAgg){
-  Select *pSub;
-  IdList *pSrc, *pSubSrc;
-  ExprList *pList;
+  Select *pSub;       /* The inner query or "subquery" */
+  IdList *pSrc;       /* The FROM clause of the outer query */
+  IdList *pSubSrc;    /* The FROM clause of the subquery */
+  ExprList *pList;    /* The result set of the outer query */
   int i;
   int iParent, iSub;
   Expr *pWhere;
@@ -954,7 +955,7 @@ int flattenSubquery(Select *p, int iFrom, int isAgg, int subqueryIsAgg){
   if( pSub->isDistinct && isAgg ) return 0;
   if( p->isDistinct && subqueryIsAgg ) return 0;
 
-  /* If we reach this point, it means flatting is permitted for the
+  /* If we reach this point, it means flattening is permitted for the
   ** i-th entry of the FROM clause in the outer query.
   */
   iParent = p->base + iFrom;
@@ -1332,6 +1333,22 @@ int sqliteSelect(
   v = sqliteGetVdbe(pParse);
   if( v==0 ) goto select_end;
 
+  /* Identify column names if we will be using in the callback.  This
+  ** step is skipped if the output is going to a table or a memory cell.
+  */
+  if( eDest==SRT_Callback ){
+    generateColumnNames(pParse, p->base, pTabList, pEList);
+  }
+
+  /* Set the limiter
+  */
+  if( p->nLimit<=0 ){
+    p->nOffset = 0;
+  }else{
+    if( p->nOffset<0 ) p->nOffset = 0;
+    sqliteVdbeAddOp(v, OP_Limit, p->nLimit, p->nOffset);
+  }
+
   /* Generate code for all sub-queries in the FROM clause
   */
   for(i=0; i<pTabList->nId; i++){
@@ -1392,23 +1409,6 @@ int sqliteSelect(
     }
   }
 
-  /* Set the limiter
-  */
-  if( p->nLimit<=0 ){
-    p->nOffset = 0;
-  }else{
-    if( p->nOffset<0 ) p->nOffset = 0;
-    sqliteVdbeAddOp(v, OP_Limit, p->nLimit, p->nOffset);
-  }
-    
-
-  /* Identify column names if we will be using in the callback.  This
-  ** step is skipped if the output is going to a table or a memory cell.
-  */
-  if( eDest==SRT_Callback ){
-    generateColumnNames(pParse, p->base, pTabList, pEList);
-  }
-
   /* Reset the aggregator
   */
   if( isAgg ){