Ensure consistent results when FormSortKeys fails to find

all the expected keys (it was returning uninitialized memory).

diff --git a/src/backend/executor/nodeSort.c b/src/backend/executor/nodeSort.c
index 13a05948e70fe34c4dd0a3ff77158ab89ff17e8e..1ca99c1bef70adaa78f41738861db0597230902b 100644 (file)
--- a/src/backend/executor/nodeSort.c
+++ b/src/backend/executor/nodeSort.c
@@ -7,11 +7,12 @@
  *
  *
  * IDENTIFICATION
- *       $Header: /cvsroot/pgsql/src/backend/executor/nodeSort.c,v 1.18 1999/02/13 23:15:27 momjian Exp $
+ *       $Header: /cvsroot/pgsql/src/backend/executor/nodeSort.c,v 1.19 1999/06/03 03:17:37 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
 #include "postgres.h"
+#include <string.h>
 
 #include "executor/executor.h"
 #include "executor/execdebug.h"
@@ -58,6 +59,7 @@ FormSortKeys(Sort *sortnode)
        if (keycount <= 0)
                elog(ERROR, "FormSortKeys: keycount <= 0");
        sortkeys = (ScanKey) palloc(keycount * sizeof(ScanKeyData));
+       MemSet((char *) sortkeys, 0, keycount * sizeof(ScanKeyData));
 
        /* ----------------
         *      form each scan key from the resdom info in the target list
@@ -72,7 +74,7 @@ FormSortKeys(Sort *sortnode)
                reskey = resdom->reskey;
                reskeyop = resdom->reskeyop;
 
-               if (reskey > 0)
+               if (reskey > 0)                 /* ignore TLEs that are not sort keys */
                {
                        ScanKeyEntryInitialize(&sortkeys[reskey - 1],
                                                                   0,