Index: src/vdbe.c
==================================================================
--- src/vdbe.c
+++ src/vdbe.c
@@ -41,11 +41,11 @@
 ** documentation, headers files, or other derived files.  The formatting
 ** of the code in this file is, therefore, important.  See other comments
 ** in this file for details.  If in doubt, do not deviate from existing
 ** commenting and indentation practices when changing or adding code.
 **
-** $Id: vdbe.c,v 1.418 2004/10/06 15:41:17 drh Exp $
+** $Id: vdbe.c,v 1.419 2004/10/19 16:40:59 drh Exp $
 */
 #include "sqliteInt.h"
 #include "os.h"
 #include <ctype.h>
 #include "vdbeInt.h"
@@ -4235,11 +4235,24 @@
 */
 case OP_AggGet: {
   AggElem *pFocus;
   int i = pOp->p2;
   pFocus = p->agg.pCurrent;
-  if( pFocus==0 ) goto no_mem;
+  if( pFocus==0 ){
+    int res;
+    if( sqlite3_malloc_failed ) goto no_mem;
+    rc = sqlite3BtreeFirst(p->agg.pCsr, &res);
+    if( rc!=SQLITE_OK ){
+      return rc;
+    }
+    if( res!=0 ){
+      rc = AggInsert(&p->agg,"",1);
+      pFocus = p->agg.pCurrent;
+    }else{
+      rc = sqlite3BtreeData(p->agg.pCsr, 0, 4, (char *)&pFocus);
+    }
+  }
   assert( i>=0 && i<p->agg.nMem );
   pTos++;
   sqlite3VdbeMemShallowCopy(pTos, &pFocus->aMem[i], MEM_Ephem);
   if( pTos->flags&MEM_Str ){
     sqlite3VdbeChangeEncoding(pTos, db->enc);

Index: test/misc4.test
==================================================================
--- test/misc4.test
+++ test/misc4.test
@@ -11,11 +11,11 @@
 # This file implements regression tests for SQLite library.
 #
 # This file implements tests for miscellanous features that were
 # left out of other test files.
 #
-# $Id: misc4.test,v 1.6 2004/07/24 17:38:30 drh Exp $
+# $Id: misc4.test,v 1.7 2004/10/19 16:40:59 drh Exp $
 
 set testdir [file dirname $argv0]
 source $testdir/tester.tcl
 
 # Prepare a statement that will create a temporary table.  Then do
@@ -80,7 +80,22 @@
   catchsql {
     INSERT INTO t3 VALUES(1);
   }
 } {0 {}}
 
+# Ticket #966
+#
+do_test misc4-3.1 {
+  execsql { 
+    CREATE TABLE Table1(ID integer primary key, Value TEXT);
+    INSERT INTO Table1 VALUES(1, 'x');
+    CREATE TABLE Table2(ID integer NOT NULL, Value TEXT);
+    INSERT INTO Table2 VALUES(1, 'z');
+    INSERT INTO Table2 VALUES (1, 'a');
+    SELECT ID, Value FROM Table1
+       UNION SELECT ID, max(Value) FROM Table2 GROUP BY 1,2
+    ORDER BY 1, 2;
+  }
+} {{} {} 1 x 1 z}
+
 
 finish_test