BUG#13081: Disable ROR-index_merge for NDB tables (by adding a

HA_KEY_SCAN_NOT_ROR index flag) as NDB index scans are not guaranteed to be ROR 
scans. 

sql/ha_ndbcluster.cc

@@ -1209,7 +1209,8 @@ inline ulong ha_ndbcluster::index_flags(uint idx_no, uint part,
   DBUG_ENTER("ha_ndbcluster::index_flags");
   DBUG_PRINT("info", ("idx_no: %d", idx_no));
   DBUG_ASSERT(get_index_type_from_table(idx_no) < index_flags_size);
-  DBUG_RETURN(index_type_flags[get_index_type_from_table(idx_no)]);
+  DBUG_RETURN(index_type_flags[get_index_type_from_table(idx_no)] | 
+              HA_KEY_SCAN_NOT_ROR);
 }
 
 static void shrink_varchar(Field* field, const byte* & ptr, char* buf)

sql/handler.h

@@ -98,6 +98,13 @@
 #define HA_ONLY_WHOLE_INDEX	16	/* Can't use part key searches */
 #define HA_KEYREAD_ONLY         64	/* Support HA_EXTRA_KEYREAD */
 
+/*
+  Index scan will not return records in rowid order. Not guaranteed to be
+  set for unordered (e.g. HASH) indexes.
+*/
+#define HA_KEY_SCAN_NOT_ROR     128 
+
+
 /* operations for disable/enable indexes */
 #define HA_KEY_SWITCH_NONUNIQ      0
 #define HA_KEY_SWITCH_ALL          1

sql/opt_range.cc

@@ -5117,6 +5117,8 @@ check_quick_select(PARAM *param,uint idx,SEL_ARG *tree)
     if (cpk_scan)
       param->is_ror_scan= TRUE;
   }
+  if (param->table->file->index_flags(key, 0, TRUE) & HA_KEY_SCAN_NOT_ROR)
+    param->is_ror_scan= FALSE;
   DBUG_PRINT("exit", ("Records: %lu", (ulong) records));
   DBUG_RETURN(records);
 }