Merge.

2 files changed, 71 insertions, 2 deletions

diff --git a/mysql-test/r/derived_view.result b/mysql-test/r/derived_view.result
index 49e1422c3d4..28c4c362a9d 100644
--- a/mysql-test/r/derived_view.result
+++ b/mysql-test/r/derived_view.result
@@ -1960,6 +1960,42 @@ ON ( COLUMNS.TABLE_SCHEMA = UNIQUES.TABLE_SCHEMA);
 COUNT(*) > 0
 1
 DROP TABLE t1;
-set SESSION optimizer_switch= @save_optimizer_switch;
+SET SESSION optimizer_switch= @save_optimizer_switch;
+#
+# LP BUG#953649: crash when estimating the cost of a look-up  
+#                into a derived table to be materialized 
+#
+CREATE TABLE t1 (a int);
+INSERT INTO t1 VALUES (132);
+CREATE TABLE t2 (b int, c varchar(256));
+INSERT INTO t2 VALUES (132,'test1'), (120,'text2'), (132,'text3');
+CREATE VIEW v AS
+SELECT b, GROUP_CONCAT(c) AS gc FROM t2 GROUP BY b;
+SET @save_optimizer_switch=@@optimizer_switch;
+SET SESSION optimizer_switch='derived_merge=off';
+SET SESSION optimizer_switch='derived_with_keys=off';
+EXPLAIN
+SELECT * FROM t1, v WHERE a = b;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t1	system	NULL	NULL	NULL	NULL	1	
+1	PRIMARY	<derived2>	ALL	NULL	NULL	NULL	NULL	3	Using where
+2	DERIVED	t2	ALL	NULL	NULL	NULL	NULL	3	Using filesort
+SELECT * FROM t1, v WHERE a = b;
+a	b	gc
+132	132	test1,text3
+SET SESSION optimizer_switch='derived_merge=on';
+SET SESSION optimizer_switch='derived_with_keys=on';
+EXPLAIN
+SELECT * FROM t1, v WHERE a = b;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t1	system	NULL	NULL	NULL	NULL	1	
+1	PRIMARY	<derived2>	ref	key0	key0	5	const	0	
+2	DERIVED	t2	ALL	NULL	NULL	NULL	NULL	3	Using filesort
+SELECT * FROM t1, v WHERE a = b;
+a	b	gc
+132	132	test1,text3
+SET SESSION optimizer_switch= @save_optimizer_switch;
+DROP VIEW v;
+DROP TABLE t1,t2;
 set optimizer_switch=@exit_optimizer_switch;
 set join_cache_level=@exit_join_cache_level;
diff --git a/mysql-test/t/derived_view.test b/mysql-test/t/derived_view.test
index 9660dd1e5f5..d1ed2ff5ba6 100644
--- a/mysql-test/t/derived_view.test
+++ b/mysql-test/t/derived_view.test
@@ -1345,7 +1345,40 @@ SELECT COUNT(*) > 0
 
 DROP TABLE t1;
 
-set SESSION optimizer_switch= @save_optimizer_switch;
+SET SESSION optimizer_switch= @save_optimizer_switch;
+
+--echo #
+--echo # LP BUG#953649: crash when estimating the cost of a look-up  
+--echo #                into a derived table to be materialized 
+--echo #
+
+CREATE TABLE t1 (a int);
+INSERT INTO t1 VALUES (132);
+
+CREATE TABLE t2 (b int, c varchar(256));
+INSERT INTO t2 VALUES (132,'test1'), (120,'text2'), (132,'text3');
+
+CREATE VIEW v AS
+  SELECT b, GROUP_CONCAT(c) AS gc FROM t2 GROUP BY b;
+
+SET @save_optimizer_switch=@@optimizer_switch;
+
+SET SESSION optimizer_switch='derived_merge=off'; 
+SET SESSION optimizer_switch='derived_with_keys=off'; 
+EXPLAIN
+SELECT * FROM t1, v WHERE a = b;
+SELECT * FROM t1, v WHERE a = b;
+
+SET SESSION optimizer_switch='derived_merge=on'; 
+SET SESSION optimizer_switch='derived_with_keys=on'; 
+EXPLAIN
+SELECT * FROM t1, v WHERE a = b;
+SELECT * FROM t1, v WHERE a = b;
+
+SET SESSION optimizer_switch= @save_optimizer_switch;
+
+DROP VIEW v;
+DROP TABLE t1,t2;
 
 # The following command must be the last one the file 
 set optimizer_switch=@exit_optimizer_switch;