Fix the sqlite3ExprDup() routine so that it makes complete duplications of
subqueries containing window functions.
FossilOrigin-Name: 940174543e87184a0278fcd02e8a096a11510174d9c1d65d21878819790ddaff
diff --git a/src/expr.c b/src/expr.c
index fb44a7e..a6bb441 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -1330,6 +1330,32 @@
# define withDup(x,y) 0
#endif
+#ifndef SQLITE_OMIT_WINDOWFUNC
+/*
+** The gatherSelectWindows() procedure and its helper routine
+** gatherSelectWindowsCallback() are used to scan all the expressions
+** an a newly duplicated SELECT statement and gather all of the Window
+** objects found there, assembling them onto the linked list at Select->pWin.
+*/
+static int gatherSelectWindowsCallback(Walker *pWalker, Expr *pExpr){
+ if( pExpr->op==TK_FUNCTION && pExpr->y.pWin!=0 ){
+ assert( ExprHasProperty(pExpr, EP_WinFunc) );
+ pExpr->y.pWin->pNextWin = pWalker->u.pSelect->pWin;
+ pWalker->u.pSelect->pWin = pExpr->y.pWin;
+ }
+ return WRC_Continue;
+}
+static void gatherSelectWindows(Select *p){
+ Walker w;
+ w.xExprCallback = gatherSelectWindowsCallback;
+ w.xSelectCallback = 0;
+ w.u.pSelect = p;
+ sqlite3WalkSelectExpr(&w, p);
+ sqlite3WalkSelectFrom(&w, p);
+}
+#endif
+
+
/*
** The following group of routines make deep copies of expressions,
** expression lists, ID lists, and select statements. The copies can
@@ -1497,6 +1523,7 @@
#ifndef SQLITE_OMIT_WINDOWFUNC
pNew->pWin = 0;
pNew->pWinDefn = sqlite3WindowListDup(db, p->pWinDefn);
+ if( p->pWin ) gatherSelectWindows(pNew);
#endif
pNew->selId = p->selId;
*pp = pNew;