Apply fix by oystein.grovlen@sun.com 2010-03-12:

Bug#48213 Materialized subselect crashes if using GEOMETRY type

The problem occurred because during semi-join a materialized table
was created which contained a GEOMETRY column, which is a specialized
BLOB column.  This caused an segmentation fault because such tables will
have extra columns, and the semi-join code was not prepared for that.

The solution is to disable materialization when Blob/Geometry columns would 
need to be materialized.  Blob columns cannot be used for index look-up 
anyway, so it does not makes sense to use materialization.

This fix implies that it is detected earlier that subquery materialization
can not be used.  The result of that is that in->exist optimization may
be performed for such queries.  Hence, extended query plans for such
queries had to be updated.

mysql-test/r/subselect_mat.result:
  Update extended query plan for subqueries that cannot use materialization
  due to Blobs.
mysql-test/r/subselect_sj.result:
  Updated result file.
mysql-test/r/subselect_sj_jcl6.result:
  Update result file.
mysql-test/t/subselect_sj.test:
  Add test case for Bug#48213 that verifies that semi-join works when subquery select list contain Blob columns.  Also verify that materialization is not
  used.
sql/opt_subselect.cc:
  Disable materialization for semi-join/subqueries when the subquery select list
  contain Blob columns.

1 files changed, 6 insertions, 0 deletions

diff --git a/sql/opt_subselect.cc b/sql/opt_subselect.cc
index 37e55aea3bc..0593856bd60 100644
--- a/sql/opt_subselect.cc
+++ b/sql/opt_subselect.cc
@@ -322,7 +322,13 @@ bool subquery_types_allow_materialization(Item_in_subselect *in_subs)
     default:
       ;/* suitable for materialization */
     }
+
+    // Materialization does not work with BLOB columns
+    if (inner->field_type() == MYSQL_TYPE_BLOB || 
+	inner->field_type() == MYSQL_TYPE_GEOMETRY)
+        DBUG_RETURN(FALSE);
   }
+    
   in_subs->types_allow_materialization= TRUE;
   in_subs->sjm_scan_allowed= all_are_fields;
   DBUG_PRINT("info",("subquery_types_allow_materialization: ok, allowed"));