Wrong result with ICP, outer join, subquery in maria-5.3-icp

[Philip Stoev]

The following query:

SELECT *
FROM t1
LEFT JOIN t2
ON 1
WHERE ( t2.b ) NOT IN (
        SELECT t4.b
        FROM t3, t4
        WHERE t4.b <= 2
        AND t4.c = t3.c
);

returns no rows when executed with maria-5.3-icp and index_condition_pushdown=ON and {c,NULL} in all other cases. The issue is also reproducible without empty/constant tables. The issue is also reproducible with realistic ON conditions.

explain:

id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 1
1 PRIMARY t2 ALL NULL NULL NULL NULL 1 Using where
2 DEPENDENT SUBQUERY t3 ALL NULL NULL NULL NULL 1
2 DEPENDENT SUBQUERY t4 ref_or_null b b 5 func 2 Using index condition; Using where; Full scan on NULL key

minimal switch: index_condition_pushdown=ON;
full switch: index_merge=on,index_merge_union=on,index_merge_sort_union=on,index_merge_intersection=on,index_merge_sort_intersection=off,index_condition_pushdown=on,derived_merge=off,derived_with_keys=off,firstmatch=off,loosescan=off,materialization=off,in_to_exists=on,semijoin=off,partial_match_rowid_merge=on,partial_match_table_scan=on,subquery_cache=on,mrr=off,mrr_cost_based=off,mrr_sort_keys=off,outer_join_with_cache=off,semijoin_with_cache=off,join_cache_incremental=on,join_cache_hashed=on,join_cache_bka=on,optimize_join_buffer_size=off,table_elimination=on

 bzr version-info
revision-id: <email address hidden>
date: 2011-11-06 01:23:03 -0700
build-date: 2011-11-07 10:39:33 +0200
revno: 3269
branch-nick: maria-5.3-icp

test case:

CREATE TABLE t1 ( c varchar(1)) ENGINE=InnoDB;
INSERT INTO t1 VALUES ('c');

CREATE TABLE t2 ( b int) ENGINE=InnoDB;

CREATE TABLE t3 ( c varchar(1)) ENGINE=InnoDB;
INSERT INTO t3 VALUES ('c');

CREATE TABLE t4 ( b int, c varchar(1), KEY (b)) ENGINE=InnoDB;
INSERT INTO t4 VALUES (7,'c');

SET SESSION optimizer_switch='index_condition_pushdown=ON';
SELECT *
FROM t1
LEFT JOIN t2
ON 1
WHERE ( t2.b ) NOT IN (
        SELECT t4.b
        FROM t3, t4
        WHERE t4.b <= 2
        AND t4.c = t3.c
);

[Sergey Petrunia (sergefp)]

A testcase with MyISAM (without const tables):
drop table t1,t2,t3,t4;

CREATE TABLE t1 (c varchar(1));
INSERT INTO t1 VALUES ('c'), ('c');

CREATE TABLE t2 (c varchar(1), b int);
INSERT INTO t2 VALUES ('d', NULL),('d', NULL);

CREATE TABLE t3 (c varchar(1));
INSERT INTO t3 VALUES ('c');
INSERT INTO t3 VALUES ('c');

CREATE TABLE t4 ( b int, c varchar(1), KEY (b));
INSERT INTO t4 VALUES (7,'c');
INSERT INTO t4 VALUES (7,'c');

SET SESSION optimizer_switch='index_condition_pushdown=ON';
explain
SELECT *
FROM t1
LEFT JOIN t2
ON t1.c=t2.b
WHERE ( t2.b ) NOT IN (
        SELECT t4.b
        FROM t3 STRAIGHT_JOIN t4
        WHERE t4.b <= 2
        AND t4.c = t3.c
);