Merge epotemkin@bk-internal.mysql.com:/home/bk/mysql-5.0-opt

into  moonbone.local:/mnt/gentoo64/work/12122-bug-5.0-opt-mysql

mysql-test/r/view.result

@@ -3078,4 +3078,43 @@ b
 2
 DROP VIEW v1;
 DROP TABLE t1,t2;
+create table t1(f1 int, f2 int);
+insert into t1 values(1,2),(1,3),(1,1),(2,3),(2,1),(2,2);
+select * from t1;
+f1	f2
+1	2
+1	3
+1	1
+2	3
+2	1
+2	2
+create view v1 as select * from t1 order by f2;
+select * from v1;
+f1	f2
+1	1
+2	1
+1	2
+2	2
+1	3
+2	3
+explain extended select * from v1;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	6	Using filesort
+Warnings:
+Note	1003	select `test`.`t1`.`f1` AS `f1`,`test`.`t1`.`f2` AS `f2` from `test`.`t1` order by `test`.`t1`.`f2`
+select * from v1 order by f1;
+f1	f2
+1	1
+1	2
+1	3
+2	1
+2	2
+2	3
+explain extended select * from v1 order by f1;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	6	Using filesort
+Warnings:
+Note	1003	select `test`.`t1`.`f1` AS `f1`,`test`.`t1`.`f2` AS `f2` from `test`.`t1` order by `test`.`t1`.`f1`,`test`.`t1`.`f2`
+drop view v1;
+drop table t1;
 End of 5.0 tests.

mysql-test/t/view.test

@@ -3024,4 +3024,18 @@ SELECT * FROM t2;
 DROP VIEW v1;
 DROP TABLE t1,t2;
 
+#
+# Bug#12122: Views with ORDER BY can't be resolved using MERGE algorithm.
+#
+create table t1(f1 int, f2 int);
+insert into t1 values(1,2),(1,3),(1,1),(2,3),(2,1),(2,2);
+select * from t1;
+create view v1 as select * from t1 order by f2;
+select * from v1;
+explain extended select * from v1;
+select * from v1 order by f1;
+explain extended select * from v1 order by f1;
+drop view v1;
+drop table t1;
+
 --echo End of 5.0 tests.

sql/sql_lex.cc

@@ -1751,7 +1751,6 @@ bool st_lex::can_be_merged()
   }
 
   return (selects_allow_merge &&
-	  select_lex.order_list.elements == 0 &&
 	  select_lex.group_list.elements == 0 &&
 	  select_lex.having == 0 &&
           select_lex.with_sum_func == 0 &&