Fixed bug lp:1000649

Analysis:

When the method JOIN::choose_subquery_plan() decided to apply
the IN-TO-EXISTS strategy, it set the unit and select_lex
uncacheable flag to UNCACHEABLE_DEPENDENT_INJECTED unconditionally.
As result, even if IN-TO-EXISTS injected non-correlated predicates,
the subquery was still treated as correlated.

Solution:
Set the subquery as correlated only if the injected predicate(s) depend
on the outer query.

1 files changed, 1 insertions, 1 deletions

diff --git a/mysql-test/r/join_outer.result b/mysql-test/r/join_outer.result
index 45aaa0b7a8e..17bc705b4f3 100644
--- a/mysql-test/r/join_outer.result
+++ b/mysql-test/r/join_outer.result
@@ -1647,7 +1647,7 @@ SELECT t2.a FROM t1 LEFT JOIN t2 ON (6) IN (SELECT a FROM t3);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	t1	system	NULL	NULL	NULL	NULL	1	100.00	
 1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	1	100.00	Using where
-2	DEPENDENT SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	2	100.00	Using where
+2	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	2	100.00	Using where
 Warnings:
 Note	1003	select `test`.`t2`.`a` AS `a` from `test`.`t1` left join `test`.`t2` on(<in_optimizer>(6,<exists>(select `test`.`t3`.`a` from `test`.`t3` where (6 = `test`.`t3`.`a`)))) where 1
 DROP TABLE t1,t2,t3;