SET SESSION optimizer_switch = 'firstmatch=off,index_merge=on,index_merge_union=on,index_merge_sort_union=on,index_merge_intersection=on,loosescan=on,materialization=on,semijoin=on';
CREATE TABLE t0 (a INT);
INSERT INTO t0 VALUES (0),(1),(2),(3),(4);
CREATE TABLE t1 (a INT, b INT, KEY(a));
INSERT INTO t1 SELECT a, a from t0;
CREATE TABLE t2 (a INT, b INT, PRIMARY KEY(a));
INSERT INTO t2 SELECT * FROM t1;
UPDATE t1 SET a=3, b=11 WHERE a=4;
UPDATE t2 SET b=11 WHERE a=3;

# This result is wrong, but will be fixed by Bug#46556
SELECT * FROM t0 WHERE t0.a IN 
(SELECT t1.a FROM t1, t2 WHERE t2.a=t0.a AND t1.b=t2.b);
a
0
1
2
3
SET join_cache_level = 6;

# This result is even more wrong ;-)
SELECT * FROM t0 WHERE t0.a IN 
(SELECT t1.a FROM t1, t2 WHERE t2.a=t0.a AND t1.b=t2.b);
a
0
1
2
3
SET SESSION optimizer_switch = 'semijoin=off';

# This result is correct
SELECT * FROM t0 WHERE t0.a IN 
(SELECT t1.a FROM t1, t2 WHERE t2.a=t0.a AND t1.b=t2.b);
a
0
1
2
3
DROP TABLE t0, t1, t2;