Implement MySQL framework to support consistent read views in

cursors. This should fix Bug#11813 when InnoDB part is in 
(tested with a draft patch).
The idea of the patch is that if a storage engine supports
consistent read views, we open one when open a cursor,
set is as the active view when fetch from the cursor, and close
together with cursor close.

1 files changed, 6 insertions, 0 deletions

diff --git a/sql/sql_select.h b/sql/sql_select.h
index 7f6d661a4de..1fa246370c6 100644
--- a/sql/sql_select.h
+++ b/sql/sql_select.h
@@ -389,6 +389,12 @@ class Cursor: public Sql_alloc, public Query_arena
   TABLE *derived_tables;
   /* List of items created during execution */
   query_id_t query_id;
+  struct Engine_info
+  {
+    const handlerton *ht;
+    void *read_view;
+  };
+  Engine_info ht_info[MAX_HA];
 public:
   Item_change_list change_list;
   select_send result;