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-rw-r--r--mysql-test/t/subselect.test10
1 files changed, 10 insertions, 0 deletions
diff --git a/mysql-test/t/subselect.test b/mysql-test/t/subselect.test
index 6369e4edbeb..3d7050ebc25 100644
--- a/mysql-test/t/subselect.test
+++ b/mysql-test/t/subselect.test
@@ -5063,4 +5063,14 @@ SET SESSION sql_mode=@old_sql_mode;
DEALLOCATE PREPARE stmt;
DROP TABLE t1;
+--echo #
+--echo # LP BUG#833777 Performance regression with deeply nested subqueries
+--echo #
+
+create table t1 (a int not null, b char(10) not null);
+insert into t1 values (1, 'a');
+set @@optimizer_switch='in_to_exists=on,semijoin=off,materialization=off,subquery_cache=off';
+select a from t1 where a in (select a from t1 where a in (select a from t1 where a in (select a from t1 where a in (select a from t1 where a in (select a from t1 where a in (select a from t1 where a in (select a from t1 where a in (select a from t1 where a in (select a from t1 where a in (select a from t1 where a in (select a from t1 where a in (select a from t1 where a in (select a from t1 where a in (select a from t1 where a in (select a from t1 where a in (select a from t1 where a in (select a from t1 where a in (select a from t1 where a in (select a from t1 where a in (select a from t1 where a in (select a from t1 where a in (select a from t1 where a in (select a from t1 where a in (select a from t1 where a in (select a from t1 where a in (select a from t1 where a in (select a from t1 where a in (select a from t1 where a in (select a from t1)))))))))))))))))))))))))))));
+drop table t1;
+
set optimizer_switch=@subselect_tmp;