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Diffstat (limited to 'mysql-test/t/selectivity.test')
| -rw-r--r-- | mysql-test/t/selectivity.test | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/mysql-test/t/selectivity.test b/mysql-test/t/selectivity.test index 3e60f242083..cf12bdaea21 100644 --- a/mysql-test/t/selectivity.test +++ b/mysql-test/t/selectivity.test @@ -1045,6 +1045,24 @@ SELECT * FROM (SELECT t FROM t1 WHERE d IS NULL) sq; DROP TABLE t1; +--echo # +--echo # MDEV-16374: filtered shows 0 for materilization scan for a semi join, which makes optimizer +--echo # always pick materialization scan over materialization lookup +--echo # + +create table t0(a int); +insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9); +create table t1 (a int, b int); +insert into t1 values (0,0),(1,1),(2,2),(3,3),(4,4),(5,5),(6,6),(7,7),(8,8),(9,9),(10,10), +(11,11),(12,12),(13,13),(14,14),(15,15); +set @@optimizer_use_condition_selectivity=2; +explain extended select * from t1 where a in (select max(a) from t1 group by b); +select * from t1 where a in (select max(a) from t1 group by b); +set @@optimizer_use_condition_selectivity=1; +explain extended select * from t1 where a in (select max(a) from t1 group by b); +select * from t1 where a in (select max(a) from t1 group by b); +drop table t1,t0; + set histogram_size=@save_histogram_size; set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity; set use_stat_tables=@save_use_stat_tables; |