Make sure any window definitions in an ORDER BY clause are removed from

the SELECT statement if the ORDER BY clause gets optimized out.

src/resolve.c

@@ -1295,7 +1295,8 @@ int sqlite3ResolveOrderGroupBy(
 
 #ifndef SQLITE_OMIT_WINDOWFUNC
 /*
-** Walker callback for resolveRemoveWindows().
+** Walker callback for sqlite3WindowRemoveExprFromSelect() and
+** sqlite3WindowRemoveExprListFromSelect()
 */
 static int resolveRemoveWindowsCb(Walker *pWalker, Expr *pExpr){
   if( ExprHasProperty(pExpr, EP_WinFunc) ){
@@ -1314,16 +1315,33 @@ static int resolveRemoveWindowsCb(Walker *pWalker, Expr *pExpr){
 ** Remove any Window objects owned by the expression pExpr from the
 ** Select.pWin list of Select object pSelect.
 */
-static void resolveRemoveWindows(Select *pSelect, Expr *pExpr){
-  Walker sWalker;
-  memset(&sWalker, 0, sizeof(Walker));
-  sWalker.xExprCallback = resolveRemoveWindowsCb;
-  sWalker.u.pSelect = pSelect;
-  sqlite3WalkExpr(&sWalker, pExpr);
+void sqlite3WindowRemoveExprFromSelect(Select *pSelect, Expr *pExpr){
+  if( pSelect->pWin ){
+    Walker sWalker;
+    memset(&sWalker, 0, sizeof(Walker));
+    sWalker.xExprCallback = resolveRemoveWindowsCb;
+    sWalker.u.pSelect = pSelect;
+    sqlite3WalkExpr(&sWalker, pExpr);
+  }
 }
-#else
-# define resolveRemoveWindows(x,y)
-#endif
+
+/*
+** Remove any Window objects owned by the expression list from the
+** Select.pWin list of Select object pSelect.
+*/
+void sqlite3WindowRemoveExprListFromSelect(Select *pSelect, ExprList *pList){
+  if( pList && pSelect->pWin ){
+    int i;
+    Walker sWalker;
+    memset(&sWalker, 0, sizeof(Walker));
+    sWalker.xExprCallback = resolveRemoveWindowsCb;
+    sWalker.u.pSelect = pSelect;
+    for(i=0; i<pList->nExpr; i++){
+      sqlite3WalkExpr(&sWalker, pList->a[i].pExpr);
+    }
+  }
+}
+#endif /* SQLITE_OMIT_WINDOWFUNC */
 
 /*
 ** pOrderBy is an ORDER BY or GROUP BY clause in SELECT statement pSelect.
@@ -1394,7 +1412,7 @@ static int resolveOrderGroupBy(
         /* Since this expresion is being changed into a reference
         ** to an identical expression in the result set, remove all Window
         ** objects belonging to the expression from the Select.pWin list. */
-        resolveRemoveWindows(pSelect, pE);
+        sqlite3WindowRemoveExprFromSelect(pSelect, pE);
         pItem->u.x.iOrderByCol = j+1;
       }
     }

src/select.c

@@ -5661,6 +5661,7 @@ int sqlite3Select(
            pDest->eDest==SRT_DistQueue || pDest->eDest==SRT_Fifo);
     /* If ORDER BY makes no difference in the output then neither does
     ** DISTINCT so it can be removed too. */
+    sqlite3WindowRemoveExprListFromSelect(p, p->pOrderBy);
     sqlite3ExprListDelete(db, p->pOrderBy);
     p->pOrderBy = 0;
     p->selFlags &= ~SF_Distinct;

src/sqliteInt.h

@@ -3627,10 +3627,14 @@ Window *sqlite3WindowListDup(sqlite3 *db, Window *p);
 void sqlite3WindowFunctions(void);
 void sqlite3WindowChain(Parse*, Window*, Window*);
 Window *sqlite3WindowAssemble(Parse*, Window*, ExprList*, ExprList*, Token*);
+void sqlite3WindowRemoveExprFromSelect(Select*,Expr*);
+void sqlite3WindowRemoveExprListFromSelect(Select*,ExprList*);
 #else
 # define sqlite3WindowDelete(a,b)
 # define sqlite3WindowFunctions()
 # define sqlite3WindowAttach(a,b,c)
+# define sqlite3WindowRemoveExprFromSelect(Select*,Expr*);
+# define sqlite3WindowRemoveExprListFromSelect(Select*,ExprList*);
 #endif
 
 /*