MWL#90: Subqueries: Inside-out execution for non-semijoin materialized subqueries that are AND-parts of the WHERE

- Code cleanu. - Make MWL#90 code require @@optimizer_switch='semijoin=on' - Update test results with the above - Fork subselect_mat.test - we want to check both semi-join materialization, which now has broader scope and non-semijoin materialization.
2025-08-07 00:04:31 +03:00 · 2010-05-25 10:32:15 +04:00
parent 5a53be655c
commit 62bf7f6124
9 changed files with 2399 additions and 1126 deletions
--- a/mysql-test/r/subselect_mat.result
+++ b/mysql-test/r/subselect_mat.result
@@ -1,3 +1,5 @@
 set @@optimizer_switch='semijoin=off';
 set optimizer_switch='firstmatch=off';
 drop table if exists t1, t2, t3, t1i, t2i, t3i;
 drop view if exists v1, v2, v1m, v2m;
 create table t1 (a1 char(8), a2 char(8));
@@ -30,7 +32,6 @@ create index it3i3 on t3i (c1, c2);
 insert into t1i select * from t1;
 insert into t2i select * from t2;
 insert into t3i select * from t3;
 set @@optimizer_switch='semijoin=off';
 /******************************************************************************
 * Simple tests.
 ******************************************************************************/
@@ -38,11 +39,10 @@ set @@optimizer_switch='semijoin=off';
 explain extended
 select * from t1 where a1 in (select b1 from t2 where b1 > '0');
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	9	test.t1.a1	1	100.00	
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	5	100.00	Using where
 Warnings:
-Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from  <materialize> (select `test`.`t2`.`b1` AS `b1` from `test`.`t2` where (`test`.`t2`.`b1` > '0')) join `test`.`t1` where (`SUBQUERY#2`.`b1` = `test`.`t1`.`a1`)
+Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where <in_optimizer>(`test`.`t1`.`a1`,`test`.`t1`.`a1` in ( <materialize> (select `test`.`t2`.`b1` AS `b1` from `test`.`t2` where (`test`.`t2`.`b1` > '0') ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key where ((`test`.`t1`.`a1` = `SUBQUERY#2`.`b1`)))))
 select * from t1 where a1 in (select b1 from t2 where b1 > '0');
 a1	a2
 1 - 01	2 - 01
@@ -50,11 +50,10 @@ a1	a2
 explain extended
 select * from t1 where a1 in (select b1 from t2 where b1 > '0' group by b1);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	9	test.t1.a1	1	100.00	
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	5	100.00	Using where; Using temporary; Using filesort
 Warnings:
-Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from  <materialize> (select `test`.`t2`.`b1` AS `b1` from `test`.`t2` where (`test`.`t2`.`b1` > '0') group by `test`.`t2`.`b1`) join `test`.`t1` where (`SUBQUERY#2`.`b1` = `test`.`t1`.`a1`)
+Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where <in_optimizer>(`test`.`t1`.`a1`,`test`.`t1`.`a1` in ( <materialize> (select `test`.`t2`.`b1` AS `b1` from `test`.`t2` where (`test`.`t2`.`b1` > '0') group by `test`.`t2`.`b1` ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key where ((`test`.`t1`.`a1` = `SUBQUERY#2`.`b1`)))))
 select * from t1 where a1 in (select b1 from t2 where b1 > '0' group by b1);
 a1	a2
 1 - 01	2 - 01
@@ -62,11 +61,10 @@ a1	a2
 explain extended
 select * from t1 where (a1, a2) in (select b1, b2 from t2 where b1 > '0' group by b1, b2);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	18	test.t1.a1,test.t1.a2	1	100.00	
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	5	100.00	Using where; Using temporary; Using filesort
 Warnings:
-Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from  <materialize> (select `test`.`t2`.`b1` AS `b1`,`test`.`t2`.`b2` AS `b2` from `test`.`t2` where (`test`.`t2`.`b1` > '0') group by `test`.`t2`.`b1`,`test`.`t2`.`b2`) join `test`.`t1` where ((`SUBQUERY#2`.`b2` = `test`.`t1`.`a2`) and (`SUBQUERY#2`.`b1` = `test`.`t1`.`a1`))
+Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where <in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),(`test`.`t1`.`a1`,`test`.`t1`.`a2`) in ( <materialize> (select `test`.`t2`.`b1` AS `b1`,`test`.`t2`.`b2` AS `b2` from `test`.`t2` where (`test`.`t2`.`b1` > '0') group by `test`.`t2`.`b1`,`test`.`t2`.`b2` ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key where ((`test`.`t1`.`a1` = `SUBQUERY#2`.`b1`) and (`test`.`t1`.`a2` = `SUBQUERY#2`.`b2`)))))
 select * from t1 where (a1, a2) in (select b1, b2 from t2 where b1 > '0' group by b1, b2);
 a1	a2
 1 - 01	2 - 01
@@ -74,11 +72,10 @@ a1	a2
 explain extended
 select * from t1 where (a1, a2) in (select b1, min(b2) from t2 where b1 > '0' group by b1);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	18	test.t1.a1,test.t1.a2	1	100.00	
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	5	100.00	Using where; Using temporary; Using filesort
 Warnings:
-Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from  <materialize> (select `test`.`t2`.`b1` AS `b1`,min(`test`.`t2`.`b2`) AS `min(b2)` from `test`.`t2` where (`test`.`t2`.`b1` > '0') group by `test`.`t2`.`b1`) join `test`.`t1` where ((`SUBQUERY#2`.`min(b2)` = `test`.`t1`.`a2`) and (`SUBQUERY#2`.`b1` = `test`.`t1`.`a1`))
+Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where <in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),(`test`.`t1`.`a1`,`test`.`t1`.`a2`) in ( <materialize> (select `test`.`t2`.`b1` AS `b1`,min(`test`.`t2`.`b2`) AS `min(b2)` from `test`.`t2` where (`test`.`t2`.`b1` > '0') group by `test`.`t2`.`b1` ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key where ((`test`.`t1`.`a1` = `SUBQUERY#2`.`b1`) and (`test`.`t1`.`a2` = `SUBQUERY#2`.`min(b2)`)))))
 select * from t1 where (a1, a2) in (select b1, min(b2) from t2 where b1 > '0' group by b1);
 a1	a2
 1 - 01	2 - 01
@@ -86,11 +83,10 @@ a1	a2
 explain extended
 select * from t1i where a1 in (select b1 from t2i where b1 > '0');
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t1i	index	it1i1,it1i3	it1i3	18	NULL	3	100.00	Using index
+1	PRIMARY	t1i	index	NULL	it1i3	18	NULL	3	100.00	Using where; Using index
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	9	test.t1i.a1	1	100.00	
 2	SUBQUERY	t2i	index	it2i1,it2i3	it2i1	9	NULL	5	100.00	Using where; Using index
 Warnings:
-Note	1003	select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from  <materialize> (select `test`.`t2i`.`b1` AS `b1` from `test`.`t2i` where (`test`.`t2i`.`b1` > '0')) join `test`.`t1i` where (`SUBQUERY#2`.`b1` = `test`.`t1i`.`a1`)
+Note	1003	select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from `test`.`t1i` where <in_optimizer>(`test`.`t1i`.`a1`,`test`.`t1i`.`a1` in ( <materialize> (select `test`.`t2i`.`b1` AS `b1` from `test`.`t2i` where (`test`.`t2i`.`b1` > '0') ), <primary_index_lookup>(`test`.`t1i`.`a1` in <temporary table> on distinct_key where ((`test`.`t1i`.`a1` = `SUBQUERY#2`.`b1`)))))
 select * from t1i where a1 in (select b1 from t2i where b1 > '0');
 a1	a2
 1 - 01	2 - 01
@@ -98,11 +94,10 @@ a1	a2
 explain extended
 select * from t1i where a1 in (select b1 from t2i where b1 > '0' group by b1);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	SUBQUERY#2	ALL	distinct_key	#	NULL	#	3	100.00	#
+1	PRIMARY	t1i	index	NULL	#	18	#	3	100.00	#
 1	PRIMARY	t1i	ref	it1i1,it1i3	#	9	#	1	100.00	#
 2	SUBQUERY	t2i	range	it2i1,it2i3	#	9	#	3	100.00	#
 Warnings:
-Note	1003	select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from  <materialize> (select `test`.`t2i`.`b1` AS `b1` from `test`.`t2i` where (`test`.`t2i`.`b1` > '0') group by `test`.`t2i`.`b1`) join `test`.`t1i` where (`test`.`t1i`.`a1` = `SUBQUERY#2`.`b1`)
+Note	1003	select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from `test`.`t1i` where <in_optimizer>(`test`.`t1i`.`a1`,`test`.`t1i`.`a1` in ( <materialize> (select `test`.`t2i`.`b1` AS `b1` from `test`.`t2i` where (`test`.`t2i`.`b1` > '0') group by `test`.`t2i`.`b1` ), <primary_index_lookup>(`test`.`t1i`.`a1` in <temporary table> on distinct_key where ((`test`.`t1i`.`a1` = `SUBQUERY#2`.`b1`)))))
 select * from t1i where a1 in (select b1 from t2i where b1 > '0' group by b1);
 a1	a2
 1 - 01	2 - 01
@@ -110,11 +105,10 @@ a1	a2
 explain extended
 select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0');
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t1i	index	it1i1,it1i2,it1i3	it1i3	18	NULL	3	100.00	Using index
+1	PRIMARY	t1i	index	NULL	it1i3	18	NULL	3	100.00	Using where; Using index
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	18	test.t1i.a1,test.t1i.a2	1	100.00	
 2	SUBQUERY	t2i	index	it2i1,it2i3	it2i3	18	NULL	5	100.00	Using where; Using index
 Warnings:
-Note	1003	select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from  <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b1` > '0')) join `test`.`t1i` where ((`SUBQUERY#2`.`b2` = `test`.`t1i`.`a2`) and (`SUBQUERY#2`.`b1` = `test`.`t1i`.`a1`))
+Note	1003	select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from `test`.`t1i` where <in_optimizer>((`test`.`t1i`.`a1`,`test`.`t1i`.`a2`),(`test`.`t1i`.`a1`,`test`.`t1i`.`a2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b1` > '0') ), <primary_index_lookup>(`test`.`t1i`.`a1` in <temporary table> on distinct_key where ((`test`.`t1i`.`a1` = `SUBQUERY#2`.`b1`) and (`test`.`t1i`.`a2` = `SUBQUERY#2`.`b2`)))))
 select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0');
 a1	a2
 1 - 01	2 - 01
@@ -122,11 +116,10 @@ a1	a2
 explain extended
 select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0' group by b1, b2);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t1i	index	it1i1,it1i2,it1i3	#	#	#	3	100.00	#
+1	PRIMARY	t1i	index	NULL	#	#	#	3	100.00	#
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	#	#	#	1	100.00	#
 2	SUBQUERY	t2i	range	it2i1,it2i3	#	#	#	3	100.00	#
 Warnings:
-Note	1003	select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from  <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b1` > '0') group by `test`.`t2i`.`b1`,`test`.`t2i`.`b2`) join `test`.`t1i` where ((`SUBQUERY#2`.`b2` = `test`.`t1i`.`a2`) and (`SUBQUERY#2`.`b1` = `test`.`t1i`.`a1`))
+Note	1003	select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from `test`.`t1i` where <in_optimizer>((`test`.`t1i`.`a1`,`test`.`t1i`.`a2`),(`test`.`t1i`.`a1`,`test`.`t1i`.`a2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b1` > '0') group by `test`.`t2i`.`b1`,`test`.`t2i`.`b2` ), <primary_index_lookup>(`test`.`t1i`.`a1` in <temporary table> on distinct_key where ((`test`.`t1i`.`a1` = `SUBQUERY#2`.`b1`) and (`test`.`t1i`.`a2` = `SUBQUERY#2`.`b2`)))))
 select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0' group by b1, b2);
 a1	a2
 1 - 01	2 - 01
@@ -134,11 +127,10 @@ a1	a2
 explain extended
 select * from t1i where (a1, a2) in (select b1, min(b2) from t2i where b1 > '0' group by b1);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t1i	index	it1i1,it1i2,it1i3	#	#	#	3	100.00	#
+1	PRIMARY	t1i	index	NULL	#	#	#	3	100.00	#
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	#	#	#	1	100.00	#
 2	SUBQUERY	t2i	range	it2i1,it2i3	#	#	#	3	100.00	#
 Warnings:
-Note	1003	select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from  <materialize> (select `test`.`t2i`.`b1` AS `b1`,min(`test`.`t2i`.`b2`) AS `min(b2)` from `test`.`t2i` where (`test`.`t2i`.`b1` > '0') group by `test`.`t2i`.`b1`) join `test`.`t1i` where ((`SUBQUERY#2`.`min(b2)` = `test`.`t1i`.`a2`) and (`SUBQUERY#2`.`b1` = `test`.`t1i`.`a1`))
+Note	1003	select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from `test`.`t1i` where <in_optimizer>((`test`.`t1i`.`a1`,`test`.`t1i`.`a2`),(`test`.`t1i`.`a1`,`test`.`t1i`.`a2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,min(`test`.`t2i`.`b2`) AS `min(b2)` from `test`.`t2i` where (`test`.`t2i`.`b1` > '0') group by `test`.`t2i`.`b1` ), <primary_index_lookup>(`test`.`t1i`.`a1` in <temporary table> on distinct_key where ((`test`.`t1i`.`a1` = `SUBQUERY#2`.`b1`) and (`test`.`t1i`.`a2` = `SUBQUERY#2`.`min(b2)`)))))
 select * from t1i where (a1, a2) in (select b1, min(b2) from t2i where b1 > '0' group by b1);
 a1	a2
 1 - 01	2 - 01
@@ -146,11 +138,10 @@ a1	a2
 explain extended
 select * from t1 where (a1, a2) in (select b1, max(b2) from t2i group by b1);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	18	test.t1.a1,test.t1.a2	1	100.00	
 2	SUBQUERY	t2i	range	NULL	it2i3	9	NULL	3	100.00	Using index for group-by
 Warnings:
-Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from  <materialize> (select `test`.`t2i`.`b1` AS `b1`,max(`test`.`t2i`.`b2`) AS `max(b2)` from `test`.`t2i` group by `test`.`t2i`.`b1`) join `test`.`t1` where ((`SUBQUERY#2`.`max(b2)` = `test`.`t1`.`a2`) and (`SUBQUERY#2`.`b1` = `test`.`t1`.`a1`))
+Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where <in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),(`test`.`t1`.`a1`,`test`.`t1`.`a2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,max(`test`.`t2i`.`b2`) AS `max(b2)` from `test`.`t2i` group by `test`.`t2i`.`b1` ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key where ((`test`.`t1`.`a1` = `SUBQUERY#2`.`b1`) and (`test`.`t1`.`a2` = `SUBQUERY#2`.`max(b2)`)))))
 select * from t1 where (a1, a2) in (select b1, max(b2) from t2i group by b1);
 a1	a2
 1 - 01	2 - 01
@@ -158,13 +149,11 @@ a1	a2
 prepare st1 from "explain select * from t1 where (a1, a2) in (select b1, max(b2) from t2i group by b1)";
 execute st1;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	Using where
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	18	test.t1.a1,test.t1.a2	1	
 2	SUBQUERY	t2i	range	NULL	it2i3	9	NULL	3	Using index for group-by
 execute st1;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	Using where
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	18	test.t1.a1,test.t1.a2	1	
 2	SUBQUERY	t2i	range	NULL	it2i3	9	NULL	3	Using index for group-by
 prepare st2 from "select * from t1 where (a1, a2) in (select b1, max(b2) from t2i group by b1)";
 execute st2;
@@ -178,17 +167,17 @@ a1	a2
 explain extended
 select * from t1 where (a1, a2) in (select b1, min(b2) from t2i where b1 > '0' group by b1);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	18	test.t1.a1,test.t1.a2	1	100.00	
 2	SUBQUERY	t2i	range	it2i1,it2i3	it2i3	18	NULL	3	100.00	Using where; Using index for group-by
 Warnings:
-Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from  <materialize> (select `test`.`t2i`.`b1` AS `b1`,min(`test`.`t2i`.`b2`) AS `min(b2)` from `test`.`t2i` where (`test`.`t2i`.`b1` > '0') group by `test`.`t2i`.`b1`) join `test`.`t1` where ((`SUBQUERY#2`.`min(b2)` = `test`.`t1`.`a2`) and (`SUBQUERY#2`.`b1` = `test`.`t1`.`a1`))
+Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where <in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),(`test`.`t1`.`a1`,`test`.`t1`.`a2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,min(`test`.`t2i`.`b2`) AS `min(b2)` from `test`.`t2i` where (`test`.`t2i`.`b1` > '0') group by `test`.`t2i`.`b1` ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key where ((`test`.`t1`.`a1` = `SUBQUERY#2`.`b1`) and (`test`.`t1`.`a2` = `SUBQUERY#2`.`min(b2)`)))))
 select * from t1 where (a1, a2) in (select b1, min(b2) from t2i where b1 > '0' group by b1);
 a1	a2
 1 - 01	2 - 01
 1 - 02	2 - 02
 select * from t1 where (a1, a2) in (select b1, min(b2) from t2i limit 1,1);
 ERROR 42000: This version of MySQL doesn't yet support 'LIMIT & IN/ALL/ANY/SOME subquery'
 set @save_optimizer_switch=@@optimizer_switch;
 set @@optimizer_switch='default,semijoin=off';
 prepare st1 from
 "select * from t1 where (a1, a2) in (select b1, min(b2) from t2 where b1 > '0' group by b1)";
@@ -215,15 +204,14 @@ execute st1;
 a1	a2
 1 - 01	2 - 01
 1 - 02	2 - 02
-set @@optimizer_switch='default,semijoin=off';
+set @@optimizer_switch=@save_optimizer_switch;
 explain extended
 select * from t1 where (a1, a2) in (select b1, b2 from t2 order by b1, b2);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	18	test.t1.a1,test.t1.a2	1	100.00	
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	5	100.00	
 Warnings:
-Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from  <materialize> (select `test`.`t2`.`b1` AS `b1`,`test`.`t2`.`b2` AS `b2` from `test`.`t2` order by `test`.`t2`.`b1`,`test`.`t2`.`b2`) join `test`.`t1` where ((`SUBQUERY#2`.`b2` = `test`.`t1`.`a2`) and (`SUBQUERY#2`.`b1` = `test`.`t1`.`a1`))
+Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where <in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),(`test`.`t1`.`a1`,`test`.`t1`.`a2`) in ( <materialize> (select `test`.`t2`.`b1` AS `b1`,`test`.`t2`.`b2` AS `b2` from `test`.`t2` order by `test`.`t2`.`b1`,`test`.`t2`.`b2` ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key where ((`test`.`t1`.`a1` = `SUBQUERY#2`.`b1`) and (`test`.`t1`.`a2` = `SUBQUERY#2`.`b2`)))))
 select * from t1 where (a1, a2) in (select b1, b2 from t2 order by b1, b2);
 a1	a2
 1 - 01	2 - 01
@@ -231,11 +219,10 @@ a1	a2
 explain extended
 select * from t1i where (a1, a2) in (select b1, b2 from t2i order by b1, b2);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t1i	index	it1i1,it1i2,it1i3	it1i3	18	NULL	3	100.00	Using index
+1	PRIMARY	t1i	index	NULL	it1i3	18	NULL	3	100.00	Using where; Using index
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	18	test.t1i.a1,test.t1i.a2	1	100.00	
 2	SUBQUERY	t2i	index	NULL	it2i3	18	NULL	5	100.00	Using index
 Warnings:
-Note	1003	select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from  <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` order by `test`.`t2i`.`b1`,`test`.`t2i`.`b2`) join `test`.`t1i` where ((`SUBQUERY#2`.`b2` = `test`.`t1i`.`a2`) and (`SUBQUERY#2`.`b1` = `test`.`t1i`.`a1`))
+Note	1003	select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from `test`.`t1i` where <in_optimizer>((`test`.`t1i`.`a1`,`test`.`t1i`.`a2`),(`test`.`t1i`.`a1`,`test`.`t1i`.`a2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` order by `test`.`t2i`.`b1`,`test`.`t2i`.`b2` ), <primary_index_lookup>(`test`.`t1i`.`a1` in <temporary table> on distinct_key where ((`test`.`t1i`.`a1` = `SUBQUERY#2`.`b1`) and (`test`.`t1i`.`a2` = `SUBQUERY#2`.`b2`)))))
 select * from t1i where (a1, a2) in (select b1, b2 from t2i order by b1, b2);
 a1	a2
 1 - 01	2 - 01
@@ -285,15 +272,12 @@ where (a1, a2) in (select b1, b2 from t2 where b1 >  '0') and
 (a1, a2) in (select c1, c2 from t3
 where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	SUBQUERY#2	ALL	distinct_key	NULL	NULL	NULL	5	0.00	
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
-1	PRIMARY	SUBQUERY#3	eq_ref	distinct_key	distinct_key	18	SUBQUERY#2.b1,SUBQUERY#2.b2	1	100.00	
+3	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	4	100.00	Using where
 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where; Using join buffer
 3	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	4	100.00	
 3	SUBQUERY	SUBQUERY#4	eq_ref	distinct_key	distinct_key	18	test.t3.c1,test.t3.c2	1	100.00	
 4	SUBQUERY	t2i	index	it2i2	it2i3	18	NULL	5	100.00	Using where; Using index
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	5	100.00	Using where
 Warnings:
-Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from  <materialize> (select `test`.`t3`.`c1` AS `c1`,`test`.`t3`.`c2` AS `c2` from  <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b2` > '0')) join `test`.`t3` where ((`SUBQUERY#4`.`b2` = `test`.`t3`.`c2`) and (`SUBQUERY#4`.`b1` = `test`.`t3`.`c1`))) join  <materialize> (select `test`.`t2`.`b1` AS `b1`,`test`.`t2`.`b2` AS `b2` from `test`.`t2` where (`test`.`t2`.`b1` > '0')) join `test`.`t1` where ((`SUBQUERY#3`.`c2` = `SUBQUERY#2`.`b2`) and (`test`.`t1`.`a2` = `SUBQUERY#2`.`b2`) and (`SUBQUERY#3`.`c1` = `SUBQUERY#2`.`b1`) and (`test`.`t1`.`a1` = `SUBQUERY#2`.`b1`))
+Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where (<in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),(`test`.`t1`.`a1`,`test`.`t1`.`a2`) in ( <materialize> (select `test`.`t2`.`b1` AS `b1`,`test`.`t2`.`b2` AS `b2` from `test`.`t2` where (`test`.`t2`.`b1` > '0') ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key where ((`test`.`t1`.`a1` = `SUBQUERY#2`.`b1`) and (`test`.`t1`.`a2` = `SUBQUERY#2`.`b2`))))) and <in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),(`test`.`t1`.`a1`,`test`.`t1`.`a2`) in ( <materialize> (select `test`.`t3`.`c1` AS `c1`,`test`.`t3`.`c2` AS `c2` from `test`.`t3` where <in_optimizer>((`test`.`t3`.`c1`,`test`.`t3`.`c2`),(`test`.`t3`.`c1`,`test`.`t3`.`c2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b2` > '0') ), <primary_index_lookup>(`test`.`t3`.`c1` in <temporary table> on distinct_key where ((`test`.`t3`.`c1` = `SUBQUERY#4`.`b1`) and (`test`.`t3`.`c2` = `SUBQUERY#4`.`b2`))))) ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key where ((`test`.`t1`.`a1` = `SUBQUERY#3`.`c1`) and (`test`.`t1`.`a2` = `SUBQUERY#3`.`c2`))))))
 select * from t1
 where (a1, a2) in (select b1, b2 from t2 where b1 >  '0') and
 (a1, a2) in (select c1, c2 from t3
@@ -307,15 +291,12 @@ where (a1, a2) in (select b1, b2 from t2i where b1 >  '0') and
 (a1, a2) in (select c1, c2 from t3i
 where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	SUBQUERY#2	ALL	distinct_key	#	#	#	5	0.00	#
+1	PRIMARY	t1i	index	NULL	#	#	#	3	100.00	#
-1	PRIMARY	SUBQUERY#3	eq_ref	distinct_key	#	#	#	1	100.00	#
+3	SUBQUERY	t3i	index	NULL	#	#	#	4	100.00	#
 1	PRIMARY	t1i	ref	it1i1,it1i2,it1i3	#	#	#	1	100.00	#
 3	SUBQUERY	t3i	index	it3i1,it3i2,it3i3	#	#	#	4	100.00	#
 3	SUBQUERY	SUBQUERY#4	eq_ref	distinct_key	#	#	#	1	100.00	#
 4	SUBQUERY	t2i	index	it2i2	#	#	#	5	100.00	#
 2	SUBQUERY	t2i	index	it2i1,it2i3	#	#	#	5	100.00	#
 Warnings:
-Note	1003	select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from  <materialize> (select `test`.`t3i`.`c1` AS `c1`,`test`.`t3i`.`c2` AS `c2` from  <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b2` > '0')) join `test`.`t3i` where ((`SUBQUERY#4`.`b2` = `test`.`t3i`.`c2`) and (`SUBQUERY#4`.`b1` = `test`.`t3i`.`c1`))) join  <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b1` > '0')) join `test`.`t1i` where ((`SUBQUERY#3`.`c2` = `SUBQUERY#2`.`b2`) and (`test`.`t1i`.`a2` = `SUBQUERY#2`.`b2`) and (`SUBQUERY#3`.`c1` = `SUBQUERY#2`.`b1`) and (`test`.`t1i`.`a1` = `SUBQUERY#2`.`b1`))
+Note	1003	select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from `test`.`t1i` where (<in_optimizer>((`test`.`t1i`.`a1`,`test`.`t1i`.`a2`),(`test`.`t1i`.`a1`,`test`.`t1i`.`a2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b1` > '0') ), <primary_index_lookup>(`test`.`t1i`.`a1` in <temporary table> on distinct_key where ((`test`.`t1i`.`a1` = `SUBQUERY#2`.`b1`) and (`test`.`t1i`.`a2` = `SUBQUERY#2`.`b2`))))) and <in_optimizer>((`test`.`t1i`.`a1`,`test`.`t1i`.`a2`),(`test`.`t1i`.`a1`,`test`.`t1i`.`a2`) in ( <materialize> (select `test`.`t3i`.`c1` AS `c1`,`test`.`t3i`.`c2` AS `c2` from `test`.`t3i` where <in_optimizer>((`test`.`t3i`.`c1`,`test`.`t3i`.`c2`),(`test`.`t3i`.`c1`,`test`.`t3i`.`c2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b2` > '0') ), <primary_index_lookup>(`test`.`t3i`.`c1` in <temporary table> on distinct_key where ((`test`.`t3i`.`c1` = `SUBQUERY#4`.`b1`) and (`test`.`t3i`.`c2` = `SUBQUERY#4`.`b2`))))) ), <primary_index_lookup>(`test`.`t1i`.`a1` in <temporary table> on distinct_key where ((`test`.`t1i`.`a1` = `SUBQUERY#3`.`c1`) and (`test`.`t1i`.`a2` = `SUBQUERY#3`.`c2`))))))
 select * from t1i
 where (a1, a2) in (select b1, b2 from t2i where b1 >  '0') and
 (a1, a2) in (select c1, c2 from t3i
@@ -331,17 +312,14 @@ b2 in (select c2 from t3 where c2 LIKE '%03')) and
 (a1, a2) in (select c1, c2 from t3
 where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	SUBQUERY#2	ALL	distinct_key	NULL	NULL	NULL	5	0.00	
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
-1	PRIMARY	SUBQUERY#5	eq_ref	distinct_key	distinct_key	18	SUBQUERY#2.b1,SUBQUERY#2.b2	1	100.00	
+5	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	4	100.00	Using where
 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where; Using join buffer
 5	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	4	100.00	
 5	SUBQUERY	SUBQUERY#6	eq_ref	distinct_key	distinct_key	18	test.t3.c1,test.t3.c2	1	100.00	
 6	SUBQUERY	t2i	index	it2i2	it2i3	18	NULL	5	100.00	Using where; Using index
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	5	100.00	Using where
 4	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	4	100.00	Using where
 3	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	4	100.00	Using where
 Warnings:
-Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from  <materialize> (select `test`.`t3`.`c1` AS `c1`,`test`.`t3`.`c2` AS `c2` from  <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b2` > '0')) join `test`.`t3` where ((`SUBQUERY#6`.`b2` = `test`.`t3`.`c2`) and (`SUBQUERY#6`.`b1` = `test`.`t3`.`c1`))) join  <materialize> (select `test`.`t2`.`b1` AS `b1`,`test`.`t2`.`b2` AS `b2` from `test`.`t2` where (<in_optimizer>(`test`.`t2`.`b2`,`test`.`t2`.`b2` in ( <materialize> (select `test`.`t3`.`c2` AS `c2` from `test`.`t3` where (`test`.`t3`.`c2` like '%02') ), <primary_index_lookup>(`test`.`t2`.`b2` in <temporary table> on distinct_key where ((`test`.`t2`.`b2` = `SUBQUERY#3`.`c2`))))) or <in_optimizer>(`test`.`t2`.`b2`,`test`.`t2`.`b2` in ( <materialize> (select `test`.`t3`.`c2` AS `c2` from `test`.`t3` where (`test`.`t3`.`c2` like '%03') ), <primary_index_lookup>(`test`.`t2`.`b2` in <temporary table> on distinct_key where ((`test`.`t2`.`b2` = `SUBQUERY#4`.`c2`))))))) join `test`.`t1` where ((`SUBQUERY#5`.`c2` = `SUBQUERY#2`.`b2`) and (`test`.`t1`.`a2` = `SUBQUERY#2`.`b2`) and (`SUBQUERY#5`.`c1` = `SUBQUERY#2`.`b1`) and (`test`.`t1`.`a1` = `SUBQUERY#2`.`b1`))
+Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where (<in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),(`test`.`t1`.`a1`,`test`.`t1`.`a2`) in ( <materialize> (select `test`.`t2`.`b1` AS `b1`,`test`.`t2`.`b2` AS `b2` from `test`.`t2` where (<in_optimizer>(`test`.`t2`.`b2`,`test`.`t2`.`b2` in ( <materialize> (select `test`.`t3`.`c2` AS `c2` from `test`.`t3` where (`test`.`t3`.`c2` like '%02') ), <primary_index_lookup>(`test`.`t2`.`b2` in <temporary table> on distinct_key where ((`test`.`t2`.`b2` = `SUBQUERY#3`.`c2`))))) or <in_optimizer>(`test`.`t2`.`b2`,`test`.`t2`.`b2` in ( <materialize> (select `test`.`t3`.`c2` AS `c2` from `test`.`t3` where (`test`.`t3`.`c2` like '%03') ), <primary_index_lookup>(`test`.`t2`.`b2` in <temporary table> on distinct_key where ((`test`.`t2`.`b2` = `SUBQUERY#4`.`c2`)))))) ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key where ((`test`.`t1`.`a1` = `SUBQUERY#2`.`b1`) and (`test`.`t1`.`a2` = `SUBQUERY#2`.`b2`))))) and <in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),(`test`.`t1`.`a1`,`test`.`t1`.`a2`) in ( <materialize> (select `test`.`t3`.`c1` AS `c1`,`test`.`t3`.`c2` AS `c2` from `test`.`t3` where <in_optimizer>((`test`.`t3`.`c1`,`test`.`t3`.`c2`),(`test`.`t3`.`c1`,`test`.`t3`.`c2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b2` > '0') ), <primary_index_lookup>(`test`.`t3`.`c1` in <temporary table> on distinct_key where ((`test`.`t3`.`c1` = `SUBQUERY#6`.`b1`) and (`test`.`t3`.`c2` = `SUBQUERY#6`.`b2`))))) ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key where ((`test`.`t1`.`a1` = `SUBQUERY#5`.`c1`) and (`test`.`t1`.`a2` = `SUBQUERY#5`.`c2`))))))
 select * from t1
 where (a1, a2) in (select b1, b2 from t2
 where b2 in (select c2 from t3 where c2 LIKE '%02') or
@@ -359,16 +337,14 @@ b2 in (select c2 from t3 t3b where c2 LIKE '%03')) and
 where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
-1	PRIMARY	SUBQUERY#5	eq_ref	distinct_key	distinct_key	18	test.t1.a1,test.t1.a2	1	100.00	
+5	SUBQUERY	t3c	ALL	NULL	NULL	NULL	NULL	4	100.00	Using where
 5	SUBQUERY	t3c	ALL	NULL	NULL	NULL	NULL	4	100.00	
 5	SUBQUERY	SUBQUERY#6	eq_ref	distinct_key	distinct_key	18	test.t3c.c1,test.t3c.c2	1	100.00	
 6	SUBQUERY	t2i	index	it2i2	it2i3	18	NULL	5	100.00	Using where; Using index
 2	DEPENDENT SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	5	100.00	Using where
 4	SUBQUERY	t3b	ALL	NULL	NULL	NULL	NULL	4	100.00	Using where
 3	DEPENDENT SUBQUERY	t3a	ALL	NULL	NULL	NULL	NULL	4	100.00	Using where
 Warnings:
 Note	1276	Field or reference 'test.t1.a1' of SELECT #3 was resolved in SELECT #1
-Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from  <materialize> (select `test`.`t3c`.`c1` AS `c1`,`test`.`t3c`.`c2` AS `c2` from  <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b2` > '0')) join `test`.`t3` `t3c` where ((`SUBQUERY#6`.`b2` = `test`.`t3c`.`c2`) and (`SUBQUERY#6`.`b1` = `test`.`t3c`.`c1`))) join `test`.`t1` where ((`SUBQUERY#5`.`c2` = `test`.`t1`.`a2`) and (`SUBQUERY#5`.`c1` = `test`.`t1`.`a1`) and <in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),<exists>(select `test`.`t2`.`b1` AS `b1`,`test`.`t2`.`b2` AS `b2` from `test`.`t2` where ((<in_optimizer>(`test`.`t2`.`b2`,<exists>(select 1 AS `Not_used` from `test`.`t3` `t3a` where ((`test`.`t3a`.`c1` = `test`.`t1`.`a1`) and (<cache>(`test`.`t2`.`b2`) = `test`.`t3a`.`c2`)))) or <in_optimizer>(`test`.`t2`.`b2`,`test`.`t2`.`b2` in ( <materialize> (select `test`.`t3b`.`c2` AS `c2` from `test`.`t3` `t3b` where (`test`.`t3b`.`c2` like '%03') ), <primary_index_lookup>(`test`.`t2`.`b2` in <temporary table> on distinct_key where ((`test`.`t2`.`b2` = `SUBQUERY#4`.`c2`)))))) and (<cache>(`test`.`t1`.`a1`) = `test`.`t2`.`b1`) and (<cache>(`test`.`t1`.`a2`) = `test`.`t2`.`b2`)))))
+Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where (<in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),<exists>(select `test`.`t2`.`b1` AS `b1`,`test`.`t2`.`b2` AS `b2` from `test`.`t2` where ((<in_optimizer>(`test`.`t2`.`b2`,<exists>(select 1 AS `Not_used` from `test`.`t3` `t3a` where ((`test`.`t3a`.`c1` = `test`.`t1`.`a1`) and (<cache>(`test`.`t2`.`b2`) = `test`.`t3a`.`c2`)))) or <in_optimizer>(`test`.`t2`.`b2`,`test`.`t2`.`b2` in ( <materialize> (select `test`.`t3b`.`c2` AS `c2` from `test`.`t3` `t3b` where (`test`.`t3b`.`c2` like '%03') ), <primary_index_lookup>(`test`.`t2`.`b2` in <temporary table> on distinct_key where ((`test`.`t2`.`b2` = `SUBQUERY#4`.`c2`)))))) and (<cache>(`test`.`t1`.`a1`) = `test`.`t2`.`b1`) and (<cache>(`test`.`t1`.`a2`) = `test`.`t2`.`b2`)))) and <in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),(`test`.`t1`.`a1`,`test`.`t1`.`a2`) in ( <materialize> (select `test`.`t3c`.`c1` AS `c1`,`test`.`t3c`.`c2` AS `c2` from `test`.`t3` `t3c` where <in_optimizer>((`test`.`t3c`.`c1`,`test`.`t3c`.`c2`),(`test`.`t3c`.`c1`,`test`.`t3c`.`c2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b2` > '0') ), <primary_index_lookup>(`test`.`t3c`.`c1` in <temporary table> on distinct_key where ((`test`.`t3c`.`c1` = `SUBQUERY#6`.`b1`) and (`test`.`t3c`.`c2` = `SUBQUERY#6`.`b2`))))) ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key where ((`test`.`t1`.`a1` = `SUBQUERY#5`.`c1`) and (`test`.`t1`.`a2` = `SUBQUERY#5`.`c2`))))))
 select * from t1
 where (a1, a2) in (select b1, b2 from t2
 where b2 in (select c2 from t3 t3a where c1 = a1) or
@@ -392,25 +368,19 @@ where (a1, a2) in (select b1, b2 from t2i where b1 >  '0') and
 (a1, a2) in (select c1, c2 from t3i
 where (c1, c2) in (select b1, b2 from t2i where b2 > '0')));
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	SUBQUERY#2	ALL	distinct_key	#	#	#	5	0.00	#
 1	PRIMARY	SUBQUERY#5	eq_ref	distinct_key	#	#	#	1	100.00	#
 1	PRIMARY	t1	ALL	NULL	#	#	#	3	100.00	#
 5	SUBQUERY	t3	ALL	NULL	#	#	#	4	100.00	#
 5	SUBQUERY	SUBQUERY#6	eq_ref	distinct_key	#	#	#	1	100.00	#
 6	SUBQUERY	t2i	index	it2i2	#	#	#	5	100.00	#
 2	SUBQUERY	t2	ALL	NULL	#	#	#	5	100.00	#
 4	SUBQUERY	t3	ALL	NULL	#	#	#	4	100.00	#
 3	SUBQUERY	t3	ALL	NULL	#	#	#	4	100.00	#
-7	UNION	SUBQUERY#8	ALL	distinct_key	#	#	#	5	0.00	#
+7	UNION	t1i	index	NULL	#	#	#	3	100.00	#
-7	UNION	SUBQUERY#9	eq_ref	distinct_key	#	#	#	1	100.00	#
+9	SUBQUERY	t3i	index	NULL	#	#	#	4	100.00	#
 7	UNION	t1i	ref	it1i1,it1i2,it1i3	#	#	#	1	100.00	#
 9	SUBQUERY	t3i	index	it3i1,it3i2,it3i3	#	#	#	4	100.00	#
 9	SUBQUERY	SUBQUERY#10	eq_ref	distinct_key	#	#	#	1	100.00	#
 10	SUBQUERY	t2i	index	it2i2	#	#	#	5	100.00	#
 8	SUBQUERY	t2i	index	it2i1,it2i3	#	#	#	5	100.00	#
 NULL	UNION RESULT	<union1,7>	ALL	NULL	#	#	#	NULL	NULL	#
 Warnings:
-Note	1003	(select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from  <materialize> (select `test`.`t3`.`c1` AS `c1`,`test`.`t3`.`c2` AS `c2` from  <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b2` > '0')) join `test`.`t3` where ((`SUBQUERY#6`.`b2` = `test`.`t3`.`c2`) and (`SUBQUERY#6`.`b1` = `test`.`t3`.`c1`))) join  <materialize> (select `test`.`t2`.`b1` AS `b1`,`test`.`t2`.`b2` AS `b2` from `test`.`t2` where (<in_optimizer>(`test`.`t2`.`b2`,`test`.`t2`.`b2` in ( <materialize> (select `test`.`t3`.`c2` AS `c2` from `test`.`t3` where (`test`.`t3`.`c2` like '%02') ), <primary_index_lookup>(`test`.`t2`.`b2` in <temporary table> on distinct_key where ((`test`.`t2`.`b2` = `SUBQUERY#3`.`c2`))))) or <in_optimizer>(`test`.`t2`.`b2`,`test`.`t2`.`b2` in ( <materialize> (select `test`.`t3`.`c2` AS `c2` from `test`.`t3` where (`test`.`t3`.`c2` like '%03') ), <primary_index_lookup>(`test`.`t2`.`b2` in <temporary table> on distinct_key where ((`test`.`t2`.`b2` = `SUBQUERY#4`.`c2`)))))) group by `test`.`t2`.`b1`,`test`.`t2`.`b2`) join `test`.`t1` where ((`SUBQUERY#5`.`c2` = `SUBQUERY#2`.`b2`) and (`test`.`t1`.`a2` = `SUBQUERY#2`.`b2`) and (`SUBQUERY#5`.`c1` = `SUBQUERY#2`.`b1`) and (`test`.`t1`.`a1` = `SUBQUERY#2`.`b1`))) union (select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from  <materialize> (select `test`.`t3i`.`c1` AS `c1`,`test`.`t3i`.`c2` AS `c2` from  <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b2` > '0')) join `test`.`t3i` where ((`SUBQUERY#10`.`b2` = `test`.`t3i`.`c2`) and (`SUBQUERY#10`.`b1` = `test`.`t3i`.`c1`))) join  <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b1` > '0')) join `test`.`t1i` where ((`SUBQUERY#9`.`c2` = `SUBQUERY#8`.`b2`) and (`test`.`t1i`.`a2` = `SUBQUERY#8`.`b2`) and (`SUBQUERY#9`.`c1` = `SUBQUERY#8`.`b1`) and (`test`.`t1i`.`a1` = `SUBQUERY#8`.`b1`)))
+Note	1003	(select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where (<in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),(`test`.`t1`.`a1`,`test`.`t1`.`a2`) in ( <materialize> (select `test`.`t2`.`b1` AS `b1`,`test`.`t2`.`b2` AS `b2` from `test`.`t2` where (<in_optimizer>(`test`.`t2`.`b2`,`test`.`t2`.`b2` in ( <materialize> (select `test`.`t3`.`c2` AS `c2` from `test`.`t3` where (`test`.`t3`.`c2` like '%02') ), <primary_index_lookup>(`test`.`t2`.`b2` in <temporary table> on distinct_key where ((`test`.`t2`.`b2` = `SUBQUERY#3`.`c2`))))) or <in_optimizer>(`test`.`t2`.`b2`,`test`.`t2`.`b2` in ( <materialize> (select `test`.`t3`.`c2` AS `c2` from `test`.`t3` where (`test`.`t3`.`c2` like '%03') ), <primary_index_lookup>(`test`.`t2`.`b2` in <temporary table> on distinct_key where ((`test`.`t2`.`b2` = `SUBQUERY#4`.`c2`)))))) group by `test`.`t2`.`b1`,`test`.`t2`.`b2` ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key where ((`test`.`t1`.`a1` = `SUBQUERY#2`.`b1`) and (`test`.`t1`.`a2` = `SUBQUERY#2`.`b2`))))) and <in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),(`test`.`t1`.`a1`,`test`.`t1`.`a2`) in ( <materialize> (select `test`.`t3`.`c1` AS `c1`,`test`.`t3`.`c2` AS `c2` from `test`.`t3` where <in_optimizer>((`test`.`t3`.`c1`,`test`.`t3`.`c2`),(`test`.`t3`.`c1`,`test`.`t3`.`c2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b2` > '0') ), <primary_index_lookup>(`test`.`t3`.`c1` in <temporary table> on distinct_key where ((`test`.`t3`.`c1` = `SUBQUERY#6`.`b1`) and (`test`.`t3`.`c2` = `SUBQUERY#6`.`b2`))))) ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key where ((`test`.`t1`.`a1` = `SUBQUERY#5`.`c1`) and (`test`.`t1`.`a2` = `SUBQUERY#5`.`c2`))))))) union (select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from `test`.`t1i` where (<in_optimizer>((`test`.`t1i`.`a1`,`test`.`t1i`.`a2`),(`test`.`t1i`.`a1`,`test`.`t1i`.`a2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b1` > '0') ), <primary_index_lookup>(`test`.`t1i`.`a1` in <temporary table> on distinct_key where ((`test`.`t1i`.`a1` = `SUBQUERY#8`.`b1`) and (`test`.`t1i`.`a2` = `SUBQUERY#8`.`b2`))))) and <in_optimizer>((`test`.`t1i`.`a1`,`test`.`t1i`.`a2`),(`test`.`t1i`.`a1`,`test`.`t1i`.`a2`) in ( <materialize> (select `test`.`t3i`.`c1` AS `c1`,`test`.`t3i`.`c2` AS `c2` from `test`.`t3i` where <in_optimizer>((`test`.`t3i`.`c1`,`test`.`t3i`.`c2`),(`test`.`t3i`.`c1`,`test`.`t3i`.`c2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b2` > '0') ), <primary_index_lookup>(`test`.`t3i`.`c1` in <temporary table> on distinct_key where ((`test`.`t3i`.`c1` = `SUBQUERY#10`.`b1`) and (`test`.`t3i`.`c2` = `SUBQUERY#10`.`b2`))))) ), <primary_index_lookup>(`test`.`t1i`.`a1` in <temporary table> on distinct_key where ((`test`.`t1i`.`a1` = `SUBQUERY#9`.`c1`) and (`test`.`t1i`.`a2` = `SUBQUERY#9`.`c2`)))))))
 (select * from t1
 where (a1, a2) in (select b1, b2 from t2
 where b2 in (select c2 from t3 where c2 LIKE '%02') or
@@ -433,15 +403,13 @@ where (a1, a2) in (select * from t1 where a1 > '0' UNION select * from t2 where
 where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
-1	PRIMARY	SUBQUERY#4	eq_ref	distinct_key	distinct_key	18	test.t1.a1,test.t1.a2	1	100.00	
+4	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	4	100.00	Using where
 4	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	4	100.00	
 4	SUBQUERY	SUBQUERY#5	eq_ref	distinct_key	distinct_key	18	test.t3.c1,test.t3.c2	1	100.00	
 5	SUBQUERY	t2i	index	it2i2	it2i3	18	NULL	5	100.00	Using where; Using index
 2	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 3	DEPENDENT UNION	t2	ALL	NULL	NULL	NULL	NULL	5	100.00	Using where
 NULL	UNION RESULT	<union2,3>	ALL	NULL	NULL	NULL	NULL	NULL	NULL	
 Warnings:
-Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from  <materialize> (select `test`.`t3`.`c1` AS `c1`,`test`.`t3`.`c2` AS `c2` from  <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b2` > '0')) join `test`.`t3` where ((`SUBQUERY#5`.`b2` = `test`.`t3`.`c2`) and (`SUBQUERY#5`.`b1` = `test`.`t3`.`c1`))) join `test`.`t1` where ((`SUBQUERY#4`.`c2` = `test`.`t1`.`a2`) and (`SUBQUERY#4`.`c1` = `test`.`t1`.`a1`) and <in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),<exists>(select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where ((`test`.`t1`.`a1` > '0') and (<cache>(`test`.`t1`.`a1`) = `test`.`t1`.`a1`) and (<cache>(`test`.`t1`.`a2`) = `test`.`t1`.`a2`)) union select `test`.`t2`.`b1` AS `b1`,`test`.`t2`.`b2` AS `b2` from `test`.`t2` where ((`test`.`t2`.`b1` < '9') and (<cache>(`test`.`t1`.`a1`) = `test`.`t2`.`b1`) and (<cache>(`test`.`t1`.`a2`) = `test`.`t2`.`b2`)))))
+Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where (<in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),<exists>(select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where ((`test`.`t1`.`a1` > '0') and (<cache>(`test`.`t1`.`a1`) = `test`.`t1`.`a1`) and (<cache>(`test`.`t1`.`a2`) = `test`.`t1`.`a2`)) union select `test`.`t2`.`b1` AS `b1`,`test`.`t2`.`b2` AS `b2` from `test`.`t2` where ((`test`.`t2`.`b1` < '9') and (<cache>(`test`.`t1`.`a1`) = `test`.`t2`.`b1`) and (<cache>(`test`.`t1`.`a2`) = `test`.`t2`.`b2`)))) and <in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),(`test`.`t1`.`a1`,`test`.`t1`.`a2`) in ( <materialize> (select `test`.`t3`.`c1` AS `c1`,`test`.`t3`.`c2` AS `c2` from `test`.`t3` where <in_optimizer>((`test`.`t3`.`c1`,`test`.`t3`.`c2`),(`test`.`t3`.`c1`,`test`.`t3`.`c2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b2` > '0') ), <primary_index_lookup>(`test`.`t3`.`c1` in <temporary table> on distinct_key where ((`test`.`t3`.`c1` = `SUBQUERY#5`.`b1`) and (`test`.`t3`.`c2` = `SUBQUERY#5`.`b2`))))) ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key where ((`test`.`t1`.`a1` = `SUBQUERY#4`.`c1`) and (`test`.`t1`.`a2` = `SUBQUERY#4`.`c2`))))))
 select * from t1
 where (a1, a2) in (select * from t1 where a1 > '0' UNION select * from t2 where b1 < '9') and
 (a1, a2) in (select c1, c2 from t3
@@ -457,16 +425,14 @@ where (c1, c2) in (select b1, b2 from t2i where b2 > '0')) and
 a1 = c1;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 1	PRIMARY	SUBQUERY#4	ALL	distinct_key	NULL	NULL	NULL	4	75.00	Using where; Using join buffer
 1	PRIMARY	t3	ALL	NULL	NULL	NULL	NULL	4	100.00	Using where; Using join buffer
-4	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	4	100.00	
+4	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	4	100.00	Using where
 4	SUBQUERY	SUBQUERY#5	eq_ref	distinct_key	distinct_key	18	test.t3.c1,test.t3.c2	1	100.00	
 5	SUBQUERY	t2i	index	it2i2	it2i3	18	NULL	5	100.00	Using where; Using index
 2	DEPENDENT SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 3	DEPENDENT UNION	t2	ALL	NULL	NULL	NULL	NULL	5	100.00	Using where
 NULL	UNION RESULT	<union2,3>	ALL	NULL	NULL	NULL	NULL	NULL	NULL	
 Warnings:
-Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2`,`test`.`t3`.`c1` AS `c1`,`test`.`t3`.`c2` AS `c2` from  <materialize> (select `test`.`t3`.`c1` AS `c1`,`test`.`t3`.`c2` AS `c2` from  <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b2` > '0')) join `test`.`t3` where ((`SUBQUERY#5`.`b2` = `test`.`t3`.`c2`) and (`SUBQUERY#5`.`b1` = `test`.`t3`.`c1`))) join `test`.`t1` join `test`.`t3` where ((`test`.`t3`.`c2` = `SUBQUERY#4`.`c2`) and (`SUBQUERY#4`.`c1` = `test`.`t1`.`a1`) and (`test`.`t3`.`c1` = `test`.`t1`.`a1`) and <in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),<exists>(select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where ((`test`.`t1`.`a1` > '0') and (<cache>(`test`.`t1`.`a1`) = `test`.`t1`.`a1`) and (<cache>(`test`.`t1`.`a2`) = `test`.`t1`.`a2`)) union select `test`.`t2`.`b1` AS `b1`,`test`.`t2`.`b2` AS `b2` from `test`.`t2` where ((`test`.`t2`.`b1` < '9') and (<cache>(`test`.`t1`.`a1`) = `test`.`t2`.`b1`) and (<cache>(`test`.`t1`.`a2`) = `test`.`t2`.`b2`)))))
+Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2`,`test`.`t3`.`c1` AS `c1`,`test`.`t3`.`c2` AS `c2` from `test`.`t1` join `test`.`t3` where ((`test`.`t3`.`c1` = `test`.`t1`.`a1`) and <in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),<exists>(select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where ((`test`.`t1`.`a1` > '0') and (<cache>(`test`.`t1`.`a1`) = `test`.`t1`.`a1`) and (<cache>(`test`.`t1`.`a2`) = `test`.`t1`.`a2`)) union select `test`.`t2`.`b1` AS `b1`,`test`.`t2`.`b2` AS `b2` from `test`.`t2` where ((`test`.`t2`.`b1` < '9') and (<cache>(`test`.`t1`.`a1`) = `test`.`t2`.`b1`) and (<cache>(`test`.`t1`.`a2`) = `test`.`t2`.`b2`)))) and <in_optimizer>((`test`.`t3`.`c1`,`test`.`t3`.`c2`),(`test`.`t3`.`c1`,`test`.`t3`.`c2`) in ( <materialize> (select `test`.`t3`.`c1` AS `c1`,`test`.`t3`.`c2` AS `c2` from `test`.`t3` where <in_optimizer>((`test`.`t3`.`c1`,`test`.`t3`.`c2`),(`test`.`t3`.`c1`,`test`.`t3`.`c2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b2` > '0') ), <primary_index_lookup>(`test`.`t3`.`c1` in <temporary table> on distinct_key where ((`test`.`t3`.`c1` = `SUBQUERY#5`.`b1`) and (`test`.`t3`.`c2` = `SUBQUERY#5`.`b2`))))) ), <primary_index_lookup>(`test`.`t3`.`c1` in <temporary table> on distinct_key where ((`test`.`t3`.`c1` = `SUBQUERY#4`.`c1`) and (`test`.`t3`.`c2` = `SUBQUERY#4`.`c2`))))))
 select * from t1, t3
 where (a1, a2) in (select * from t1 where a1 > '0' UNION select * from t2 where b1 < '9') and
 (c1, c2) in (select c1, c2 from t3
@@ -585,7 +551,6 @@ a1	a2
 Test that BLOBs are not materialized (except when arguments of some functions).
 */
 # force materialization to be always considered
 set @@optimizer_switch='semijoin=off';
 set @prefix_len = 6;
 set @blob_len = 16;
 set @suffix_len = @blob_len - @prefix_len;
@@ -644,11 +609,10 @@ explain extended select left(a1,7), left(a2,7)
 from t1_16
 where a1 in (select substring(b1,1,16) from t2_16 where b1 > '0');
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t1_16	ALL	NULL	NULL	NULL	NULL	3	100.00	
+1	PRIMARY	t1_16	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	20	test.t1_16.a1	1	100.00	Using where
 2	SUBQUERY	t2_16	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 Warnings:
-Note	1003	select left(`test`.`t1_16`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_16`.`a2`,7) AS `left(a2,7)` from  <materialize> (select substr(`test`.`t2_16`.`b1`,1,16) AS `substring(b1,1,16)` from `test`.`t2_16` where (`test`.`t2_16`.`b1` > '0')) join `test`.`t1_16` where (`test`.`t1_16`.`a1` = `SUBQUERY#2`.`substring(b1,1,16)`)
+Note	1003	select left(`test`.`t1_16`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_16`.`a2`,7) AS `left(a2,7)` from `test`.`t1_16` where <in_optimizer>(`test`.`t1_16`.`a1`,`test`.`t1_16`.`a1` in ( <materialize> (select substr(`test`.`t2_16`.`b1`,1,16) AS `substring(b1,1,16)` from `test`.`t2_16` where (`test`.`t2_16`.`b1` > '0') ), <primary_index_lookup>(`test`.`t1_16`.`a1` in <temporary table> on distinct_key where ((`test`.`t1_16`.`a1` = `SUBQUERY#2`.`substring(b1,1,16)`)))))
 select left(a1,7), left(a2,7)
 from t1_16
 where a1 in (select substring(b1,1,16) from t2_16 where b1 > '0');
@@ -674,11 +638,10 @@ explain extended select left(a1,7), left(a2,7)
 from t1_16
 where a1 in (select group_concat(b1) from t2_16 group by b2);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t1_16	ALL	NULL	NULL	NULL	NULL	3	100.00	
+1	PRIMARY	t1_16	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	261	test.t1_16.a1	1	100.00	Using where
 2	SUBQUERY	t2_16	ALL	NULL	NULL	NULL	NULL	3	100.00	Using filesort
 Warnings:
-Note	1003	select left(`test`.`t1_16`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_16`.`a2`,7) AS `left(a2,7)` from  <materialize> (select group_concat(`test`.`t2_16`.`b1` separator ',') AS `group_concat(b1)` from `test`.`t2_16` group by `test`.`t2_16`.`b2`) join `test`.`t1_16` where (`test`.`t1_16`.`a1` = `SUBQUERY#2`.`group_concat(b1)`)
+Note	1003	select left(`test`.`t1_16`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_16`.`a2`,7) AS `left(a2,7)` from `test`.`t1_16` where <in_optimizer>(`test`.`t1_16`.`a1`,`test`.`t1_16`.`a1` in ( <materialize> (select group_concat(`test`.`t2_16`.`b1` separator ',') AS `group_concat(b1)` from `test`.`t2_16` group by `test`.`t2_16`.`b2` ), <primary_index_lookup>(`test`.`t1_16`.`a1` in <temporary table> on distinct_key where ((`test`.`t1_16`.`a1` = `SUBQUERY#2`.`group_concat(b1)`)))))
 select left(a1,7), left(a2,7)
 from t1_16
 where a1 in (select group_concat(b1) from t2_16 group by b2);
@@ -698,10 +661,9 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 2	DEPENDENT SUBQUERY	t1_16	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 3	DEPENDENT SUBQUERY	t2_16	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 3	DEPENDENT SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	5	100.00	Using where; Using join buffer
 3	DEPENDENT SUBQUERY	SUBQUERY#4	eq_ref	distinct_key	distinct_key	9	test.t2.b1	1	100.00	Using where
 4	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	4	100.00	Using where
 Warnings:
-Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where <in_optimizer>(concat(`test`.`t1`.`a1`,'x'),<exists>(select 1 AS `Not_used` from `test`.`t1_16` where (<in_optimizer>((`test`.`t1_16`.`a1`,`test`.`t1_16`.`a2`),<exists>(select `test`.`t2_16`.`b1` AS `b1`,`test`.`t2_16`.`b2` AS `b2` from  <materialize> (select `test`.`t3`.`c1` AS `c1` from `test`.`t3` where (`test`.`t3`.`c2` > '0')) join `test`.`t2_16` join `test`.`t2` where ((`SUBQUERY#4`.`c1` = `test`.`t2`.`b1`) and (`test`.`t2`.`b2` = substr(`test`.`t2_16`.`b2`,1,6)) and (<cache>(`test`.`t1_16`.`a1`) = `test`.`t2_16`.`b1`) and (<cache>(`test`.`t1_16`.`a2`) = `test`.`t2_16`.`b2`)))) and (<cache>(concat(`test`.`t1`.`a1`,'x')) = left(`test`.`t1_16`.`a1`,8)))))
+Note	1003	select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where <in_optimizer>(concat(`test`.`t1`.`a1`,'x'),<exists>(select 1 AS `Not_used` from `test`.`t1_16` where (<in_optimizer>((`test`.`t1_16`.`a1`,`test`.`t1_16`.`a2`),<exists>(select `test`.`t2_16`.`b1` AS `b1`,`test`.`t2_16`.`b2` AS `b2` from `test`.`t2_16` join `test`.`t2` where ((`test`.`t2`.`b2` = substr(`test`.`t2_16`.`b2`,1,6)) and <in_optimizer>(`test`.`t2`.`b1`,`test`.`t2`.`b1` in ( <materialize> (select `test`.`t3`.`c1` AS `c1` from `test`.`t3` where (`test`.`t3`.`c2` > '0') ), <primary_index_lookup>(`test`.`t2`.`b1` in <temporary table> on distinct_key where ((`test`.`t2`.`b1` = `SUBQUERY#4`.`c1`))))) and (<cache>(`test`.`t1_16`.`a1`) = `test`.`t2_16`.`b1`) and (<cache>(`test`.`t1_16`.`a2`) = `test`.`t2_16`.`b2`)))) and (<cache>(concat(`test`.`t1`.`a1`,'x')) = left(`test`.`t1_16`.`a1`,8)))))
 drop table t1_16, t2_16, t3_16;
 set @blob_len = 512;
 set @suffix_len = @blob_len - @prefix_len;
@@ -760,11 +722,10 @@ explain extended select left(a1,7), left(a2,7)
 from t1_512
 where a1 in (select substring(b1,1,512) from t2_512 where b1 > '0');
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t1_512	ALL	NULL	NULL	NULL	NULL	3	100.00	
+1	PRIMARY	t1_512	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	517	test.t1_512.a1	1	100.00	Using where
 2	SUBQUERY	t2_512	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 Warnings:
-Note	1003	select left(`test`.`t1_512`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_512`.`a2`,7) AS `left(a2,7)` from  <materialize> (select substr(`test`.`t2_512`.`b1`,1,512) AS `substring(b1,1,512)` from `test`.`t2_512` where (`test`.`t2_512`.`b1` > '0')) join `test`.`t1_512` where (`test`.`t1_512`.`a1` = `SUBQUERY#2`.`substring(b1,1,512)`)
+Note	1003	select left(`test`.`t1_512`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_512`.`a2`,7) AS `left(a2,7)` from `test`.`t1_512` where <in_optimizer>(`test`.`t1_512`.`a1`,`test`.`t1_512`.`a1` in ( <materialize> (select substr(`test`.`t2_512`.`b1`,1,512) AS `substring(b1,1,512)` from `test`.`t2_512` where (`test`.`t2_512`.`b1` > '0') ), <primary_index_lookup>(`test`.`t1_512`.`a1` in <temporary table> on distinct_key where ((`test`.`t1_512`.`a1` = `SUBQUERY#2`.`substring(b1,1,512)`)))))
 select left(a1,7), left(a2,7)
 from t1_512
 where a1 in (select substring(b1,1,512) from t2_512 where b1 > '0');
@@ -775,11 +736,10 @@ explain extended select left(a1,7), left(a2,7)
 from t1_512
 where a1 in (select group_concat(b1) from t2_512 group by b2);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t1_512	ALL	NULL	NULL	NULL	NULL	3	100.00	
+1	PRIMARY	t1_512	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	261	test.t1_512.a1	1	100.00	Using where
 2	SUBQUERY	t2_512	ALL	NULL	NULL	NULL	NULL	3	100.00	Using filesort
 Warnings:
-Note	1003	select left(`test`.`t1_512`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_512`.`a2`,7) AS `left(a2,7)` from  <materialize> (select group_concat(`test`.`t2_512`.`b1` separator ',') AS `group_concat(b1)` from `test`.`t2_512` group by `test`.`t2_512`.`b2`) join `test`.`t1_512` where (`test`.`t1_512`.`a1` = `SUBQUERY#2`.`group_concat(b1)`)
+Note	1003	select left(`test`.`t1_512`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_512`.`a2`,7) AS `left(a2,7)` from `test`.`t1_512` where <in_optimizer>(`test`.`t1_512`.`a1`,`test`.`t1_512`.`a1` in ( <materialize> (select group_concat(`test`.`t2_512`.`b1` separator ',') AS `group_concat(b1)` from `test`.`t2_512` group by `test`.`t2_512`.`b2` ), <primary_index_lookup>(`test`.`t1_512`.`a1` in <temporary table> on distinct_key where ((`test`.`t1_512`.`a1` = `SUBQUERY#2`.`group_concat(b1)`)))))
 select left(a1,7), left(a2,7)
 from t1_512
 where a1 in (select group_concat(b1) from t2_512 group by b2);
@@ -789,11 +749,10 @@ explain extended select left(a1,7), left(a2,7)
 from t1_512
 where a1 in (select group_concat(b1) from t2_512 group by b2);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t1_512	ALL	NULL	NULL	NULL	NULL	3	100.00	
+1	PRIMARY	t1_512	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	261	test.t1_512.a1	1	100.00	Using where
 2	SUBQUERY	t2_512	ALL	NULL	NULL	NULL	NULL	3	100.00	Using filesort
 Warnings:
-Note	1003	select left(`test`.`t1_512`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_512`.`a2`,7) AS `left(a2,7)` from  <materialize> (select group_concat(`test`.`t2_512`.`b1` separator ',') AS `group_concat(b1)` from `test`.`t2_512` group by `test`.`t2_512`.`b2`) join `test`.`t1_512` where (`test`.`t1_512`.`a1` = `SUBQUERY#2`.`group_concat(b1)`)
+Note	1003	select left(`test`.`t1_512`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_512`.`a2`,7) AS `left(a2,7)` from `test`.`t1_512` where <in_optimizer>(`test`.`t1_512`.`a1`,`test`.`t1_512`.`a1` in ( <materialize> (select group_concat(`test`.`t2_512`.`b1` separator ',') AS `group_concat(b1)` from `test`.`t2_512` group by `test`.`t2_512`.`b2` ), <primary_index_lookup>(`test`.`t1_512`.`a1` in <temporary table> on distinct_key where ((`test`.`t1_512`.`a1` = `SUBQUERY#2`.`group_concat(b1)`)))))
 select left(a1,7), left(a2,7)
 from t1_512
 where a1 in (select group_concat(b1) from t2_512 group by b2);
@@ -859,7 +818,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	t1_1024	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 2	DEPENDENT SUBQUERY	t2_1024	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 Warnings:
-Note	1003	select left(`test`.`t1_1024`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1024`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1024` where <in_optimizer>(`test`.`t1_1024`.`a1`,<exists>(select 1 AS `Not_used` from `test`.`t2_1024` where ((`test`.`t2_1024`.`b1` > '0') and (<cache>(`test`.`t1_1024`.`a1`) = substr(`test`.`t2_1024`.`b1`,1,1024)) and (<cache>(`test`.`t1_1024`.`a1`) = 1))))
+Note	1003	select left(`test`.`t1_1024`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1024`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1024` where <in_optimizer>(`test`.`t1_1024`.`a1`,`test`.`t1_1024`.`a1` in (select 1 AS `Not_used` from `test`.`t2_1024` where ((`test`.`t2_1024`.`b1` > '0') and (<cache>(`test`.`t1_1024`.`a1`) = substr(`test`.`t2_1024`.`b1`,1,1024)))))
 select left(a1,7), left(a2,7)
 from t1_1024
 where a1 in (select substring(b1,1,1024) from t2_1024 where b1 > '0');
@@ -870,11 +829,10 @@ explain extended select left(a1,7), left(a2,7)
 from t1_1024
 where a1 in (select group_concat(b1) from t2_1024 group by b2);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t1_1024	ALL	NULL	NULL	NULL	NULL	3	100.00	
+1	PRIMARY	t1_1024	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	261	test.t1_1024.a1	1	100.00	Using where
 2	SUBQUERY	t2_1024	ALL	NULL	NULL	NULL	NULL	3	100.00	Using filesort
 Warnings:
-Note	1003	select left(`test`.`t1_1024`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1024`.`a2`,7) AS `left(a2,7)` from  <materialize> (select group_concat(`test`.`t2_1024`.`b1` separator ',') AS `group_concat(b1)` from `test`.`t2_1024` group by `test`.`t2_1024`.`b2`) join `test`.`t1_1024` where (`test`.`t1_1024`.`a1` = `SUBQUERY#2`.`group_concat(b1)`)
+Note	1003	select left(`test`.`t1_1024`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1024`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1024` where <in_optimizer>(`test`.`t1_1024`.`a1`,`test`.`t1_1024`.`a1` in ( <materialize> (select group_concat(`test`.`t2_1024`.`b1` separator ',') AS `group_concat(b1)` from `test`.`t2_1024` group by `test`.`t2_1024`.`b2` ), <primary_index_lookup>(`test`.`t1_1024`.`a1` in <temporary table> on distinct_key where ((`test`.`t1_1024`.`a1` = `SUBQUERY#2`.`group_concat(b1)`)))))
 select left(a1,7), left(a2,7)
 from t1_1024
 where a1 in (select group_concat(b1) from t2_1024 group by b2);
@@ -884,11 +842,10 @@ explain extended select left(a1,7), left(a2,7)
 from t1_1024
 where a1 in (select group_concat(b1) from t2_1024 group by b2);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t1_1024	ALL	NULL	NULL	NULL	NULL	3	100.00	
+1	PRIMARY	t1_1024	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	261	test.t1_1024.a1	1	100.00	Using where
 2	SUBQUERY	t2_1024	ALL	NULL	NULL	NULL	NULL	3	100.00	Using filesort
 Warnings:
-Note	1003	select left(`test`.`t1_1024`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1024`.`a2`,7) AS `left(a2,7)` from  <materialize> (select group_concat(`test`.`t2_1024`.`b1` separator ',') AS `group_concat(b1)` from `test`.`t2_1024` group by `test`.`t2_1024`.`b2`) join `test`.`t1_1024` where (`test`.`t1_1024`.`a1` = `SUBQUERY#2`.`group_concat(b1)`)
+Note	1003	select left(`test`.`t1_1024`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1024`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1024` where <in_optimizer>(`test`.`t1_1024`.`a1`,`test`.`t1_1024`.`a1` in ( <materialize> (select group_concat(`test`.`t2_1024`.`b1` separator ',') AS `group_concat(b1)` from `test`.`t2_1024` group by `test`.`t2_1024`.`b2` ), <primary_index_lookup>(`test`.`t1_1024`.`a1` in <temporary table> on distinct_key where ((`test`.`t1_1024`.`a1` = `SUBQUERY#2`.`group_concat(b1)`)))))
 select left(a1,7), left(a2,7)
 from t1_1024
 where a1 in (select group_concat(b1) from t2_1024 group by b2);
@@ -954,7 +911,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	t1_1025	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 2	DEPENDENT SUBQUERY	t2_1025	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 Warnings:
-Note	1003	select left(`test`.`t1_1025`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1025`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1025` where <in_optimizer>(`test`.`t1_1025`.`a1`,<exists>(select 1 AS `Not_used` from `test`.`t2_1025` where ((`test`.`t2_1025`.`b1` > '0') and (<cache>(`test`.`t1_1025`.`a1`) = substr(`test`.`t2_1025`.`b1`,1,1025)) and (<cache>(`test`.`t1_1025`.`a1`) = 1))))
+Note	1003	select left(`test`.`t1_1025`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1025`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1025` where <in_optimizer>(`test`.`t1_1025`.`a1`,`test`.`t1_1025`.`a1` in (select 1 AS `Not_used` from `test`.`t2_1025` where ((`test`.`t2_1025`.`b1` > '0') and (<cache>(`test`.`t1_1025`.`a1`) = substr(`test`.`t2_1025`.`b1`,1,1025)))))
 select left(a1,7), left(a2,7)
 from t1_1025
 where a1 in (select substring(b1,1,1025) from t2_1025 where b1 > '0');
@@ -965,11 +922,10 @@ explain extended select left(a1,7), left(a2,7)
 from t1_1025
 where a1 in (select group_concat(b1) from t2_1025 group by b2);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t1_1025	ALL	NULL	NULL	NULL	NULL	3	100.00	
+1	PRIMARY	t1_1025	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	261	test.t1_1025.a1	1	100.00	Using where
 2	SUBQUERY	t2_1025	ALL	NULL	NULL	NULL	NULL	3	100.00	Using filesort
 Warnings:
-Note	1003	select left(`test`.`t1_1025`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1025`.`a2`,7) AS `left(a2,7)` from  <materialize> (select group_concat(`test`.`t2_1025`.`b1` separator ',') AS `group_concat(b1)` from `test`.`t2_1025` group by `test`.`t2_1025`.`b2`) join `test`.`t1_1025` where (`test`.`t1_1025`.`a1` = `SUBQUERY#2`.`group_concat(b1)`)
+Note	1003	select left(`test`.`t1_1025`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1025`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1025` where <in_optimizer>(`test`.`t1_1025`.`a1`,`test`.`t1_1025`.`a1` in ( <materialize> (select group_concat(`test`.`t2_1025`.`b1` separator ',') AS `group_concat(b1)` from `test`.`t2_1025` group by `test`.`t2_1025`.`b2` ), <primary_index_lookup>(`test`.`t1_1025`.`a1` in <temporary table> on distinct_key where ((`test`.`t1_1025`.`a1` = `SUBQUERY#2`.`group_concat(b1)`)))))
 select left(a1,7), left(a2,7)
 from t1_1025
 where a1 in (select group_concat(b1) from t2_1025 group by b2);
@@ -979,11 +935,10 @@ explain extended select left(a1,7), left(a2,7)
 from t1_1025
 where a1 in (select group_concat(b1) from t2_1025 group by b2);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t1_1025	ALL	NULL	NULL	NULL	NULL	3	100.00	
+1	PRIMARY	t1_1025	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	261	test.t1_1025.a1	1	100.00	Using where
 2	SUBQUERY	t2_1025	ALL	NULL	NULL	NULL	NULL	3	100.00	Using filesort
 Warnings:
-Note	1003	select left(`test`.`t1_1025`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1025`.`a2`,7) AS `left(a2,7)` from  <materialize> (select group_concat(`test`.`t2_1025`.`b1` separator ',') AS `group_concat(b1)` from `test`.`t2_1025` group by `test`.`t2_1025`.`b2`) join `test`.`t1_1025` where (`test`.`t1_1025`.`a1` = `SUBQUERY#2`.`group_concat(b1)`)
+Note	1003	select left(`test`.`t1_1025`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1025`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1025` where <in_optimizer>(`test`.`t1_1025`.`a1`,`test`.`t1_1025`.`a1` in ( <materialize> (select group_concat(`test`.`t2_1025`.`b1` separator ',') AS `group_concat(b1)` from `test`.`t2_1025` group by `test`.`t2_1025`.`b2` ), <primary_index_lookup>(`test`.`t1_1025`.`a1` in <temporary table> on distinct_key where ((`test`.`t1_1025`.`a1` = `SUBQUERY#2`.`group_concat(b1)`)))))
 select left(a1,7), left(a2,7)
 from t1_1025
 where a1 in (select group_concat(b1) from t2_1025 group by b2);
@@ -997,16 +952,14 @@ insert into t1bit values (b'010', b'110');
 insert into t2bit values (b'001', b'101');
 insert into t2bit values (b'010', b'110');
 insert into t2bit values (b'110', b'111');
 set @@optimizer_switch='semijoin=off';
 explain extended select bin(a1), bin(a2)
 from t1bit
 where (a1, a2) in (select b1, b2 from t2bit);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t1bit	ALL	NULL	NULL	NULL	NULL	3	100.00	
+1	PRIMARY	t1bit	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	10	test.t1bit.a1,test.t1bit.a2	1	100.00	Using where
 2	SUBQUERY	t2bit	ALL	NULL	NULL	NULL	NULL	3	100.00	
 Warnings:
-Note	1003	select conv(`test`.`t1bit`.`a1`,10,2) AS `bin(a1)`,conv(`test`.`t1bit`.`a2`,10,2) AS `bin(a2)` from  <materialize> (select `test`.`t2bit`.`b1` AS `b1`,`test`.`t2bit`.`b2` AS `b2` from `test`.`t2bit`) join `test`.`t1bit` where ((`test`.`t1bit`.`a1` = `SUBQUERY#2`.`b1`) and (`test`.`t1bit`.`a2` = `SUBQUERY#2`.`b2`))
+Note	1003	select conv(`test`.`t1bit`.`a1`,10,2) AS `bin(a1)`,conv(`test`.`t1bit`.`a2`,10,2) AS `bin(a2)` from `test`.`t1bit` where <in_optimizer>((`test`.`t1bit`.`a1`,`test`.`t1bit`.`a2`),(`test`.`t1bit`.`a1`,`test`.`t1bit`.`a2`) in ( <materialize> (select `test`.`t2bit`.`b1` AS `b1`,`test`.`t2bit`.`b2` AS `b2` from `test`.`t2bit` ), <primary_index_lookup>(`test`.`t1bit`.`a1` in <temporary table> on distinct_key where ((`test`.`t1bit`.`a1` = `SUBQUERY#2`.`b1`) and (`test`.`t1bit`.`a2` = `SUBQUERY#2`.`b2`)))))
 select bin(a1), bin(a2)
 from t1bit
 where (a1, a2) in (select b1, b2 from t2bit);
@@ -1041,7 +994,7 @@ drop table t1, t2, t3, t1i, t2i, t3i, columns;
 /******************************************************************************
 * Test the cache of the left operand of IN.
 ******************************************************************************/
-set @@optimizer_switch='semijoin=off';
+# Test that default values of Cached_item are not used for comparison
 create table t1 (s1 int);
 create table t2 (s2 int);
 insert into t1 values (5),(1),(0);
@@ -1074,11 +1027,10 @@ insert into t3 values (30);
 explain extended
 select a from t1 where a in (select c from t2 where d >= 20);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	7	100.00	
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	7	100.00	Using where
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	4	test.t1.a	1	100.00	
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	6	100.00	Using where
 Warnings:
-Note	1003	select `test`.`t1`.`a` AS `a` from  <materialize> (select `test`.`t2`.`c` AS `c` from `test`.`t2` where (`test`.`t2`.`d` >= 20)) join `test`.`t1` where (`SUBQUERY#2`.`c` = `test`.`t1`.`a`)
+Note	1003	select `test`.`t1`.`a` AS `a` from `test`.`t1` where <in_optimizer>(`test`.`t1`.`a`,`test`.`t1`.`a` in ( <materialize> (select `test`.`t2`.`c` AS `c` from `test`.`t2` where (`test`.`t2`.`d` >= 20) ), <primary_index_lookup>(`test`.`t1`.`a` in <temporary table> on distinct_key where ((`test`.`t1`.`a` = `SUBQUERY#2`.`c`)))))
 select a from t1 where a in (select c from t2 where d >= 20);
 a
 2
@@ -1089,11 +1041,10 @@ create index it1a on t1(a);
 explain extended
 select a from t1 where a in (select c from t2 where d >= 20);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t1	index	it1a	it1a	4	NULL	7	100.00	Using index
+1	PRIMARY	t1	index	NULL	it1a	4	NULL	7	100.00	Using where; Using index
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	4	test.t1.a	1	100.00	
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	6	100.00	Using where
 Warnings:
-Note	1003	select `test`.`t1`.`a` AS `a` from  <materialize> (select `test`.`t2`.`c` AS `c` from `test`.`t2` where (`test`.`t2`.`d` >= 20)) join `test`.`t1` where (`SUBQUERY#2`.`c` = `test`.`t1`.`a`)
+Note	1003	select `test`.`t1`.`a` AS `a` from `test`.`t1` where <in_optimizer>(`test`.`t1`.`a`,`test`.`t1`.`a` in ( <materialize> (select `test`.`t2`.`c` AS `c` from `test`.`t2` where (`test`.`t2`.`d` >= 20) ), <primary_index_lookup>(`test`.`t1`.`a` in <temporary table> on distinct_key where ((`test`.`t1`.`a` = `SUBQUERY#2`.`c`)))))
 select a from t1 where a in (select c from t2 where d >= 20);
 a
 2
@@ -1104,11 +1055,10 @@ insert into t2 values (1,10);
 explain extended
 select a from t1 where a in (select c from t2 where d >= 20);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t1	index	it1a	it1a	4	NULL	7	100.00	Using index
+1	PRIMARY	t1	index	NULL	it1a	4	NULL	7	100.00	Using where; Using index
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	4	test.t1.a	1	100.00	
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	7	100.00	Using where
 Warnings:
-Note	1003	select `test`.`t1`.`a` AS `a` from  <materialize> (select `test`.`t2`.`c` AS `c` from `test`.`t2` where (`test`.`t2`.`d` >= 20)) join `test`.`t1` where (`SUBQUERY#2`.`c` = `test`.`t1`.`a`)
+Note	1003	select `test`.`t1`.`a` AS `a` from `test`.`t1` where <in_optimizer>(`test`.`t1`.`a`,`test`.`t1`.`a` in ( <materialize> (select `test`.`t2`.`c` AS `c` from `test`.`t2` where (`test`.`t2`.`d` >= 20) ), <primary_index_lookup>(`test`.`t1`.`a` in <temporary table> on distinct_key where ((`test`.`t1`.`a` = `SUBQUERY#2`.`c`)))))
 select a from t1 where a in (select c from t2 where d >= 20);
 a
 2
@@ -1188,12 +1138,11 @@ create table t2 (b1 int);
 insert into t1 values (5);
 explain select min(a1) from t1 where 7 in (select b1 from t2 group by b1);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	t1	system	NULL	NULL	NULL	NULL	1	
+1	PRIMARY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Select tables optimized away
-1	PRIMARY	SUBQUERY#2	const	distinct_key	distinct_key	5	const	1	
+2	SUBQUERY	t2	system	NULL	NULL	NULL	NULL	0	const row not found
 2	SUBQUERY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	no matching row in const table
 select min(a1) from t1 where 7 in (select b1 from t2 group by b1);
 min(a1)
-NULL
+set @save_optimizer_switch=@@optimizer_switch;
 set @@optimizer_switch='default,materialization=off';
 explain select min(a1) from t1 where 7 in (select b1 from t2 group by b1);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
@@ -1204,12 +1153,10 @@ min(a1)
 set @@optimizer_switch='default,semijoin=off';
 explain select min(a1) from t1 where 7 in (select b1 from t2);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	t1	system	NULL	NULL	NULL	NULL	1	
+1	PRIMARY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Select tables optimized away
-1	PRIMARY	SUBQUERY#2	const	distinct_key	distinct_key	5	const	1	
+2	SUBQUERY	t2	system	NULL	NULL	NULL	NULL	0	const row not found
 2	SUBQUERY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	no matching row in const table
 select min(a1) from t1 where 7 in (select b1 from t2);
 min(a1)
 NULL
 set @@optimizer_switch='default,materialization=off';
 # with MariaDB and MWL#90, this particular case is solved:
 explain select min(a1) from t1 where 7 in (select b1 from t2);
@@ -1225,15 +1172,14 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 2	DEPENDENT SUBQUERY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
 select min(a1) from t1 where 7 in (select b1 from t2) or 2> 4;
 min(a1)
 set @@optimizer_switch= @save_optimizer_switch;
 drop table t1,t2;
 create table t1 (a char(2), b varchar(10));
 insert into t1 values ('a',  'aaa');
 insert into t1 values ('aa', 'aaaa');
 set @@optimizer_switch='default,semijoin=off';
 explain select a,b from t1 where b in (select a from t1);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	2	
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	2	Using where
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	3	test.t1.b	1	Using where
 2	SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	2	
 select a,b from t1 where b in (select a from t1);
 a	b
@@ -1250,6 +1196,7 @@ INSERT INTO t1 (f1, f2) VALUES (10, 1.668);
 CREATE TABLE t2 LIKE t1;
 INSERT INTO t2 VALUES (1, 1.789);
 INSERT INTO t2 VALUES (13, 1.454);
 set @save_optimizer_switch=@@optimizer_switch;
 SET @@optimizer_switch='default,semijoin=on,materialization=on';
 EXPLAIN SELECT COUNT(*) FROM t1 WHERE (f1,f2) IN (SELECT f1,f2 FROM t2);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
@@ -1259,6 +1206,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 SELECT COUNT(*) FROM t1 WHERE (f1,f2) IN (SELECT f1,f2 FROM t2);
 COUNT(*)
 2
 set @@optimizer_switch= @save_optimizer_switch;
 DROP TABLE t1, t2;
 CREATE TABLE t1 (
 pk int,
@@ -1271,6 +1219,7 @@ PRIMARY KEY (pk)
 INSERT INTO t1 VALUES (1,'o','ffff','ffff','ffoo'),(2,'f','ffff','ffff','ffff');
 CREATE TABLE t2 LIKE t1;
 INSERT INTO t2 VALUES (1,'i','iiii','iiii','iiii'),(2,'f','ffff','ffff','ffff');
 set @save_optimizer_switch=@@optimizer_switch;
 SET @@optimizer_switch='default,semijoin=on,materialization=on';
 EXPLAIN SELECT pk FROM t1 WHERE (a) IN (SELECT a FROM t2 WHERE pk > 0);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
@@ -1284,6 +1233,7 @@ SELECT pk FROM t1 WHERE (b,c,d) IN (SELECT b,c,d FROM t2 WHERE pk > 0);
 pk
 2
 DROP TABLE t1, t2;
 set optimizer_switch=@save_optimizer_switch;
 #
 # BUG#50019: Wrong result for IN-subquery with materialization
 #
@@ -1335,3 +1285,5 @@ a	a in (select a from t1)
 1	0
 2	0
 drop table t0, t1;
 set optimizer_switch='firstmatch=on';
 set @@optimizer_switch=default;
--- a/mysql-test/r/subselect_no_semijoin.result
+++ b/mysql-test/r/subselect_no_semijoin.result
@@ -1299,34 +1299,31 @@ a
 4
 explain extended select * from t2 where t2.a in (select a from t1);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	SUBQUERY#2	ALL	distinct_key	NULL	NULL	NULL	4	100.00	
+1	PRIMARY	t2	index	NULL	PRIMARY	4	NULL	4	100.00	Using where; Using index
 1	PRIMARY	t2	index	PRIMARY	PRIMARY	4	NULL	4	75.00	Using where; Using index; Using join buffer
 2	SUBQUERY	t1	index	NULL	PRIMARY	4	NULL	4	100.00	Using index
 Warnings:
-Note	1003	select `test`.`t2`.`a` AS `a` from  <materialize> (select `test`.`t1`.`a` AS `a` from `test`.`t1`) join `test`.`t2` where (`test`.`t2`.`a` = `SUBQUERY#2`.`a`)
+Note	1003	select `test`.`t2`.`a` AS `a` from `test`.`t2` where <in_optimizer>(`test`.`t2`.`a`,`test`.`t2`.`a` in ( <materialize> (select `test`.`t1`.`a` AS `a` from `test`.`t1` ), <primary_index_lookup>(`test`.`t2`.`a` in <temporary table> on distinct_key where ((`test`.`t2`.`a` = `SUBQUERY#2`.`a`)))))
 select * from t2 where t2.a in (select a from t1 where t1.b <> 30);
 a
 2
 4
 explain extended select * from t2 where t2.a in (select a from t1 where t1.b <> 30);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	SUBQUERY#2	ALL	distinct_key	NULL	NULL	NULL	4	100.00	
+1	PRIMARY	t2	index	NULL	PRIMARY	4	NULL	4	100.00	Using where; Using index
 1	PRIMARY	t2	index	PRIMARY	PRIMARY	4	NULL	4	75.00	Using where; Using index; Using join buffer
 2	SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	4	100.00	Using where
 Warnings:
-Note	1003	select `test`.`t2`.`a` AS `a` from  <materialize> (select `test`.`t1`.`a` AS `a` from `test`.`t1` where (`test`.`t1`.`b` <> 30)) join `test`.`t2` where (`test`.`t2`.`a` = `SUBQUERY#2`.`a`)
+Note	1003	select `test`.`t2`.`a` AS `a` from `test`.`t2` where <in_optimizer>(`test`.`t2`.`a`,`test`.`t2`.`a` in ( <materialize> (select `test`.`t1`.`a` AS `a` from `test`.`t1` where (`test`.`t1`.`b` <> 30) ), <primary_index_lookup>(`test`.`t2`.`a` in <temporary table> on distinct_key where ((`test`.`t2`.`a` = `SUBQUERY#2`.`a`)))))
 select * from t2 where t2.a in (select t1.a from t1,t3 where t1.b=t3.a);
 a
 2
 3
 explain extended select * from t2 where t2.a in (select t1.a from t1,t3 where t1.b=t3.a);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t2	index	PRIMARY	PRIMARY	4	NULL	4	100.00	Using index
+1	PRIMARY	t2	index	NULL	PRIMARY	4	NULL	4	100.00	Using where; Using index
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	4	test.t2.a	1	100.00	
 2	SUBQUERY	t3	index	PRIMARY	PRIMARY	4	NULL	3	100.00	Using index
 2	SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	4	100.00	Using where; Using join buffer
 Warnings:
-Note	1003	select `test`.`t2`.`a` AS `a` from  <materialize> (select `test`.`t1`.`a` AS `a` from `test`.`t1` join `test`.`t3` where (`test`.`t1`.`b` = `test`.`t3`.`a`)) join `test`.`t2` where (`SUBQUERY#2`.`a` = `test`.`t2`.`a`)
+Note	1003	select `test`.`t2`.`a` AS `a` from `test`.`t2` where <in_optimizer>(`test`.`t2`.`a`,`test`.`t2`.`a` in ( <materialize> (select `test`.`t1`.`a` AS `a` from `test`.`t1` join `test`.`t3` where (`test`.`t1`.`b` = `test`.`t3`.`a`) ), <primary_index_lookup>(`test`.`t2`.`a` in <temporary table> on distinct_key where ((`test`.`t2`.`a` = `SUBQUERY#2`.`a`)))))
 drop table t1, t2, t3;
 create table t1 (a int, b int, index a (a,b));
 create table t2 (a int, index a (a));
@@ -1345,34 +1342,31 @@ a
 4
 explain extended select * from t2 where t2.a in (select a from t1);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t2	index	a	a	5	NULL	4	100.00	Using index
+1	PRIMARY	t2	index	NULL	a	5	NULL	4	100.00	Using where; Using index
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	5	test.t2.a	1	100.00	
 2	SUBQUERY	t1	index	NULL	a	10	NULL	10004	100.00	Using index
 Warnings:
-Note	1003	select `test`.`t2`.`a` AS `a` from  <materialize> (select `test`.`t1`.`a` AS `a` from `test`.`t1`) join `test`.`t2` where (`SUBQUERY#2`.`a` = `test`.`t2`.`a`)
+Note	1003	select `test`.`t2`.`a` AS `a` from `test`.`t2` where <in_optimizer>(`test`.`t2`.`a`,`test`.`t2`.`a` in ( <materialize> (select `test`.`t1`.`a` AS `a` from `test`.`t1` ), <primary_index_lookup>(`test`.`t2`.`a` in <temporary table> on distinct_key where ((`test`.`t2`.`a` = `SUBQUERY#2`.`a`)))))
 select * from t2 where t2.a in (select a from t1 where t1.b <> 30);
 a
 2
 4
 explain extended select * from t2 where t2.a in (select a from t1 where t1.b <> 30);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t2	index	a	a	5	NULL	4	100.00	Using index
+1	PRIMARY	t2	index	NULL	a	5	NULL	4	100.00	Using where; Using index
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	5	test.t2.a	1	100.00	
 2	SUBQUERY	t1	index	NULL	a	10	NULL	10004	100.00	Using where; Using index
 Warnings:
-Note	1003	select `test`.`t2`.`a` AS `a` from  <materialize> (select `test`.`t1`.`a` AS `a` from `test`.`t1` where (`test`.`t1`.`b` <> 30)) join `test`.`t2` where (`SUBQUERY#2`.`a` = `test`.`t2`.`a`)
+Note	1003	select `test`.`t2`.`a` AS `a` from `test`.`t2` where <in_optimizer>(`test`.`t2`.`a`,`test`.`t2`.`a` in ( <materialize> (select `test`.`t1`.`a` AS `a` from `test`.`t1` where (`test`.`t1`.`b` <> 30) ), <primary_index_lookup>(`test`.`t2`.`a` in <temporary table> on distinct_key where ((`test`.`t2`.`a` = `SUBQUERY#2`.`a`)))))
 select * from t2 where t2.a in (select t1.a from t1,t3 where t1.b=t3.a);
 a
 2
 3
 explain extended select * from t2 where t2.a in (select t1.a from t1,t3 where t1.b=t3.a);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t2	index	a	a	5	NULL	4	100.00	Using index
+1	PRIMARY	t2	index	NULL	a	5	NULL	4	100.00	Using where; Using index
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	5	test.t2.a	1	100.00	
 2	SUBQUERY	t3	index	a	a	5	NULL	3	100.00	Using index
 2	SUBQUERY	t1	index	NULL	a	10	NULL	10004	100.00	Using where; Using index; Using join buffer
 Warnings:
-Note	1003	select `test`.`t2`.`a` AS `a` from  <materialize> (select `test`.`t1`.`a` AS `a` from `test`.`t1` join `test`.`t3` where (`test`.`t1`.`b` = `test`.`t3`.`a`)) join `test`.`t2` where (`SUBQUERY#2`.`a` = `test`.`t2`.`a`)
+Note	1003	select `test`.`t2`.`a` AS `a` from `test`.`t2` where <in_optimizer>(`test`.`t2`.`a`,`test`.`t2`.`a` in ( <materialize> (select `test`.`t1`.`a` AS `a` from `test`.`t1` join `test`.`t3` where (`test`.`t1`.`b` = `test`.`t3`.`a`) ), <primary_index_lookup>(`test`.`t2`.`a` in <temporary table> on distinct_key where ((`test`.`t2`.`a` = `SUBQUERY#2`.`a`)))))
 insert into t1 values (3,31);
 select * from t2 where t2.a in (select a from t1 where t1.b <> 30);
 a
@@ -1385,11 +1379,10 @@ a
 4
 explain extended select * from t2 where t2.a in (select a from t1 where t1.b <> 30);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t2	index	a	a	5	NULL	4	100.00	Using index
+1	PRIMARY	t2	index	NULL	a	5	NULL	4	100.00	Using where; Using index
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	5	test.t2.a	1	100.00	
 2	SUBQUERY	t1	index	NULL	a	10	NULL	10005	100.00	Using where; Using index
 Warnings:
-Note	1003	select `test`.`t2`.`a` AS `a` from  <materialize> (select `test`.`t1`.`a` AS `a` from `test`.`t1` where (`test`.`t1`.`b` <> 30)) join `test`.`t2` where (`SUBQUERY#2`.`a` = `test`.`t2`.`a`)
+Note	1003	select `test`.`t2`.`a` AS `a` from `test`.`t2` where <in_optimizer>(`test`.`t2`.`a`,`test`.`t2`.`a` in ( <materialize> (select `test`.`t1`.`a` AS `a` from `test`.`t1` where (`test`.`t1`.`b` <> 30) ), <primary_index_lookup>(`test`.`t2`.`a` in <temporary table> on distinct_key where ((`test`.`t2`.`a` = `SUBQUERY#2`.`a`)))))
 drop table t0, t1, t2, t3;
 create table t1 (a int, b int);
 create table t2 (a int, b int);
@@ -2840,11 +2833,10 @@ Warnings:
 Note	1003	select `test`.`t1`.`one` AS `one`,`test`.`t1`.`two` AS `two`,<in_optimizer>((`test`.`t1`.`one`,`test`.`t1`.`two`),<exists>(select `test`.`t2`.`one` AS `one`,`test`.`t2`.`two` AS `two` from `test`.`t2` where ((`test`.`t2`.`flag` = '0') and trigcond(((<cache>(`test`.`t1`.`one`) = `test`.`t2`.`one`) or isnull(`test`.`t2`.`one`))) and trigcond(((<cache>(`test`.`t1`.`two`) = `test`.`t2`.`two`) or isnull(`test`.`t2`.`two`)))) having (trigcond(<is_not_null_test>(`test`.`t2`.`one`)) and trigcond(<is_not_null_test>(`test`.`t2`.`two`))))) AS `test` from `test`.`t1`
 explain extended SELECT one,two from t1 where ROW(one,two) IN (SELECT one,two FROM t2 WHERE flag = 'N');
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	8	100.00	
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	8	100.00	Using where
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	10	test.t1.one,test.t1.two	1	100.00	
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	9	100.00	Using where
 Warnings:
-Note	1003	select `test`.`t1`.`one` AS `one`,`test`.`t1`.`two` AS `two` from  <materialize> (select `test`.`t2`.`one` AS `one`,`test`.`t2`.`two` AS `two` from `test`.`t2` where (`test`.`t2`.`flag` = 'N')) join `test`.`t1` where ((`SUBQUERY#2`.`two` = `test`.`t1`.`two`) and (`SUBQUERY#2`.`one` = `test`.`t1`.`one`))
+Note	1003	select `test`.`t1`.`one` AS `one`,`test`.`t1`.`two` AS `two` from `test`.`t1` where <in_optimizer>((`test`.`t1`.`one`,`test`.`t1`.`two`),(`test`.`t1`.`one`,`test`.`t1`.`two`) in ( <materialize> (select `test`.`t2`.`one` AS `one`,`test`.`t2`.`two` AS `two` from `test`.`t2` where (`test`.`t2`.`flag` = 'N') ), <primary_index_lookup>(`test`.`t1`.`one` in <temporary table> on distinct_key where ((`test`.`t1`.`one` = `SUBQUERY#2`.`one`) and (`test`.`t1`.`two` = `SUBQUERY#2`.`two`)))))
 explain extended SELECT one,two,ROW(one,two) IN (SELECT one,two FROM t2 WHERE flag = '0' group by one,two) as 'test' from t1;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	8	100.00	
@@ -3429,8 +3421,7 @@ AAA	8
 EXPLAIN
 SELECT * FROM t1 WHERE (a,b) = ANY (SELECT a, max(b) FROM t1 GROUP BY a);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	9	
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	9	Using where
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	23	test.t1.a,test.t1.b	1	
 2	SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	9	Using temporary; Using filesort
 ALTER TABLE t1 ADD INDEX(a);
 SELECT * FROM t1 WHERE (a,b) = ANY (SELECT a, max(b) FROM t1 GROUP BY a);
@@ -3441,8 +3432,7 @@ AAA	8
 EXPLAIN
 SELECT * FROM t1 WHERE (a,b) = ANY (SELECT a, max(b) FROM t1 GROUP BY a);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	t1	ALL	a	NULL	NULL	NULL	9	
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	9	Using where
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	23	test.t1.a,test.t1.b	1	
 2	SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	9	Using temporary; Using filesort
 DROP TABLE t1;
 create table t1( f1 int,f2 int);
@@ -4216,8 +4206,7 @@ CREATE INDEX I1 ON t1 (a);
 CREATE INDEX I2 ON t1 (b);
 EXPLAIN SELECT a,b FROM t1 WHERE b IN (SELECT a FROM t1);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	t1	ALL	I2	NULL	NULL	NULL	2	
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	2	Using where
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	2	test.t1.b	1	Using where
 2	SUBQUERY	t1	index	NULL	I1	2	NULL	2	Using index
 SELECT a,b FROM t1 WHERE b IN (SELECT a FROM t1);
 a	b
@@ -4227,16 +4216,14 @@ CREATE INDEX I1 ON t2 (a);
 CREATE INDEX I2 ON t2 (b);
 EXPLAIN SELECT a,b FROM t2 WHERE b IN (SELECT a FROM t2);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	t2	ALL	I2	NULL	NULL	NULL	2	
+1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	2	Using where
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	5	test.t2.b	1	Using where
 2	SUBQUERY	t2	index	NULL	I1	4	NULL	2	Using index
 SELECT a,b FROM t2 WHERE b IN (SELECT a FROM t2);
 a	b
 EXPLAIN
 SELECT a,b FROM t1 WHERE b IN (SELECT a FROM t1 WHERE LENGTH(a)<500);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	t1	ALL	I2	NULL	NULL	NULL	2	
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	2	Using where
 1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	2	test.t1.b	1	Using where
 2	SUBQUERY	t1	index	NULL	I1	2	NULL	2	Using where; Using index
 SELECT a,b FROM t1 WHERE b IN (SELECT a FROM t1 WHERE LENGTH(a)<500);
 a	b
@@ -4339,18 +4326,16 @@ CREATE TABLE t1 (a INT);
 INSERT INTO t1 VALUES (1),(2);
 EXPLAIN EXTENDED SELECT 1 FROM t1 WHERE 1 IN (SELECT 1 FROM t1 GROUP BY a);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	2	100.00	
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	2	100.00	Using where
 1	PRIMARY	SUBQUERY#2	const	distinct_key	distinct_key	4	const	1	100.00	
 2	SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	2	100.00	Using temporary; Using filesort
 Warnings:
-Note	1003	select 1 AS `1` from  <materialize> (select 1 AS `1` from `test`.`t1` group by `test`.`t1`.`a`) join `test`.`t1` where (`SUBQUERY#2`.`1` = 1)
+Note	1003	select 1 AS `1` from `test`.`t1` where <in_optimizer>(1,1 in ( <materialize> (select 1 AS `1` from `test`.`t1` group by `test`.`t1`.`a` ), <primary_index_lookup>(1 in <temporary table> on distinct_key where ((1 = `SUBQUERY#2`.`1`)))))
 EXPLAIN EXTENDED SELECT 1 FROM t1 WHERE 1 IN (SELECT 1 FROM t1 WHERE a > 3 GROUP BY a);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	2	100.00	
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	2	100.00	Using where
 1	PRIMARY	SUBQUERY#2	const	distinct_key	distinct_key	4	const	1	100.00	
 2	SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	2	100.00	Using where; Using temporary; Using filesort
 Warnings:
-Note	1003	select 1 AS `1` from  <materialize> (select 1 AS `1` from `test`.`t1` where (`test`.`t1`.`a` > 3) group by `test`.`t1`.`a`) join `test`.`t1` where (`SUBQUERY#2`.`1` = 1)
+Note	1003	select 1 AS `1` from `test`.`t1` where <in_optimizer>(1,1 in ( <materialize> (select 1 AS `1` from `test`.`t1` where (`test`.`t1`.`a` > 3) group by `test`.`t1`.`a` ), <primary_index_lookup>(1 in <temporary table> on distinct_key where ((1 = `SUBQUERY#2`.`1`)))))
 DROP TABLE t1;
 #
 # Bug#45061: Incorrectly market field caused wrong result.
--- a/mysql-test/r/subselect_sj_mat.result
+++ b/mysql-test/r/subselect_sj_mat.result
--- a/mysql-test/t/subselect_mat.test
+++ b/mysql-test/t/subselect_mat.test
@@ -3,930 +3,10 @@
 # (WL#1110: Subquery optimization: materialization)
 #
 --disable_warnings
 drop table if exists t1, t2, t3, t1i, t2i, t3i;
 drop view if exists v1, v2, v1m, v2m;
 --enable_warnings
 create table t1 (a1 char(8), a2 char(8));
 create table t2 (b1 char(8), b2 char(8));
 create table t3 (c1 char(8), c2 char(8));
 insert into t1 values ('1 - 00', '2 - 00');
 insert into t1 values ('1 - 01', '2 - 01');
 insert into t1 values ('1 - 02', '2 - 02');
 insert into t2 values ('1 - 01', '2 - 01');
 insert into t2 values ('1 - 01', '2 - 01');
 insert into t2 values ('1 - 02', '2 - 02');
 insert into t2 values ('1 - 02', '2 - 02');
 insert into t2 values ('1 - 03', '2 - 03');
 insert into t3 values ('1 - 01', '2 - 01');
 insert into t3 values ('1 - 02', '2 - 02');
 insert into t3 values ('1 - 03', '2 - 03');
 insert into t3 values ('1 - 04', '2 - 04');
 # Indexed columns
 create table t1i (a1 char(8), a2 char(8));
 create table t2i (b1 char(8), b2 char(8));
 create table t3i (c1 char(8), c2 char(8));
 create index it1i1 on t1i (a1);
 create index it1i2 on t1i (a2);
 create index it1i3 on t1i (a1, a2);
 create index it2i1 on t2i (b1);
 create index it2i2 on t2i (b2);
 create index it2i3 on t2i (b1, b2);
 create index it3i1 on t3i (c1);
 create index it3i2 on t3i (c2);
 create index it3i3 on t3i (c1, c2);
 insert into t1i select * from t1;
 insert into t2i select * from t2;
 insert into t3i select * from t3;
 # force the use of materialization
 set @@optimizer_switch='semijoin=off';
-/******************************************************************************
+--source t/subselect_sj_mat.test
 * Simple tests.
 ******************************************************************************/
 # non-indexed nullable fields
 explain extended
 select * from t1 where a1 in (select b1 from t2 where b1 > '0');
 select * from t1 where a1 in (select b1 from t2 where b1 > '0');
-explain extended
+set @@optimizer_switch=default;
 select * from t1 where a1 in (select b1 from t2 where b1 > '0' group by b1);
 select * from t1 where a1 in (select b1 from t2 where b1 > '0' group by b1);
 explain extended
 select * from t1 where (a1, a2) in (select b1, b2 from t2 where b1 > '0' group by b1, b2);
 select * from t1 where (a1, a2) in (select b1, b2 from t2 where b1 > '0' group by b1, b2);
 explain extended
 select * from t1 where (a1, a2) in (select b1, min(b2) from t2 where b1 > '0' group by b1);
 select * from t1 where (a1, a2) in (select b1, min(b2) from t2 where b1 > '0' group by b1);
 # indexed columns
 explain extended
 select * from t1i where a1 in (select b1 from t2i where b1 > '0');
 select * from t1i where a1 in (select b1 from t2i where b1 > '0');
 --replace_column 6 # 8 # 11 #
 explain extended
 select * from t1i where a1 in (select b1 from t2i where b1 > '0' group by b1);
 select * from t1i where a1 in (select b1 from t2i where b1 > '0' group by b1);
 explain extended
 select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0');
 select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0');
 --replace_column 6 # 7 # 8 # 11 #
 explain extended
 select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0' group by b1, b2);
 select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0' group by b1, b2);
 --replace_column 6 # 7 # 8 # 11 #
 explain extended
 select * from t1i where (a1, a2) in (select b1, min(b2) from t2i where b1 > '0' group by b1);
 select * from t1i where (a1, a2) in (select b1, min(b2) from t2i where b1 > '0' group by b1);
 # BUG#31639: Wrong plan for uncorrelated subquery when loose scan is applicable.
 explain extended
 select * from t1 where (a1, a2) in (select b1, max(b2) from t2i group by b1);
 select * from t1 where (a1, a2) in (select b1, max(b2) from t2i group by b1);
 prepare st1 from "explain select * from t1 where (a1, a2) in (select b1, max(b2) from t2i group by b1)";
 execute st1;
 execute st1;
 prepare st2 from "select * from t1 where (a1, a2) in (select b1, max(b2) from t2i group by b1)";
 execute st2;
 execute st2;
 explain extended
 select * from t1 where (a1, a2) in (select b1, min(b2) from t2i where b1 > '0' group by b1);
 select * from t1 where (a1, a2) in (select b1, min(b2) from t2i where b1 > '0' group by b1);
 -- error 1235
 select * from t1 where (a1, a2) in (select b1, min(b2) from t2i limit 1,1);
 # test re-optimization/re-execution with different execution methods
 # prepare once, exec with different modes
 set @@optimizer_switch='default,semijoin=off';
 prepare st1 from
 "select * from t1 where (a1, a2) in (select b1, min(b2) from t2 where b1 > '0' group by b1)";
 set @@optimizer_switch='default,materialization=off';
 execute st1;
 set @@optimizer_switch='default,semijoin=off';
 execute st1;
 set @@optimizer_switch='default,materialization=off';
 prepare st1 from
 "select * from t1 where (a1, a2) in (select b1, min(b2) from t2 where b1 > '0' group by b1)";
 set @@optimizer_switch='default,semijoin=off';
 execute st1;
 set @@optimizer_switch='default,materialization=off';
 execute st1;
 set @@optimizer_switch='default,semijoin=off';
 # materialize the result of ORDER BY
 # non-indexed fields
 explain extended
 select * from t1 where (a1, a2) in (select b1, b2 from t2 order by b1, b2);
 select * from t1 where (a1, a2) in (select b1, b2 from t2 order by b1, b2);
 # indexed fields
 explain extended
 select * from t1i where (a1, a2) in (select b1, b2 from t2i order by b1, b2);
 select * from t1i where (a1, a2) in (select b1, b2 from t2i order by b1, b2);
 /******************************************************************************
 * Views, UNIONs, several levels of nesting.
 ******************************************************************************/
 # materialize the result of subquery over temp-table view
 create algorithm=merge view v1 as
 select b1, c2 from t2, t3 where b2 > c2;
 create algorithm=merge view v2 as
 select b1, c2 from t2, t3 group by b2, c2;
 create algorithm=temptable view v1m as
 select b1, c2 from t2, t3 where b2 > c2;
 create algorithm=temptable view v2m as
 select b1, c2 from t2, t3 group by b2, c2;
 select * from v1 where (c2, b1) in (select c2, b1 from v2 where b1 is not null);
 select * from v1 where (c2, b1) in (select distinct c2, b1 from v2 where b1 is not null);
 select * from v1m where (c2, b1) in (select c2, b1 from v2m where b1 is not null);
 select * from v1m where (c2, b1) in (select distinct c2, b1 from v2m where b1 is not null);
 drop view v1, v2, v1m, v2m;
 # nested subqueries, views
 explain extended
 select * from t1
 where (a1, a2) in (select b1, b2 from t2 where b1 >  '0') and
      (a1, a2) in (select c1, c2 from t3
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
 select * from t1
 where (a1, a2) in (select b1, b2 from t2 where b1 >  '0') and
      (a1, a2) in (select c1, c2 from t3
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
 --replace_column 6 # 7 # 8 # 11 #
 explain extended
 select * from t1i
 where (a1, a2) in (select b1, b2 from t2i where b1 >  '0') and
      (a1, a2) in (select c1, c2 from t3i
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
 select * from t1i
 where (a1, a2) in (select b1, b2 from t2i where b1 >  '0') and
      (a1, a2) in (select c1, c2 from t3i
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
 explain extended
 select * from t1
 where (a1, a2) in (select b1, b2 from t2
                   where b2 in (select c2 from t3 where c2 LIKE '%02') or
                         b2 in (select c2 from t3 where c2 LIKE '%03')) and
      (a1, a2) in (select c1, c2 from t3
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
 select * from t1
 where (a1, a2) in (select b1, b2 from t2
                   where b2 in (select c2 from t3 where c2 LIKE '%02') or
                         b2 in (select c2 from t3 where c2 LIKE '%03')) and
      (a1, a2) in (select c1, c2 from t3
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
 # as above with correlated innermost subquery
 explain extended
 select * from t1
 where (a1, a2) in (select b1, b2 from t2
                   where b2 in (select c2 from t3 t3a where c1 = a1) or
                         b2 in (select c2 from t3 t3b where c2 LIKE '%03')) and
      (a1, a2) in (select c1, c2 from t3 t3c
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
 select * from t1
 where (a1, a2) in (select b1, b2 from t2
                   where b2 in (select c2 from t3 t3a where c1 = a1) or
                         b2 in (select c2 from t3 t3b where c2 LIKE '%03')) and
      (a1, a2) in (select c1, c2 from t3 t3c
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
 # multiple levels of nesting subqueries, unions
 --replace_column 6 # 7 # 8 # 11 #
 explain extended
 (select * from t1
 where (a1, a2) in (select b1, b2 from t2
                   where b2 in (select c2 from t3 where c2 LIKE '%02') or
                         b2 in (select c2 from t3 where c2 LIKE '%03')
                   group by b1, b2) and
      (a1, a2) in (select c1, c2 from t3
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0')))
 UNION
 (select * from t1i
 where (a1, a2) in (select b1, b2 from t2i where b1 >  '0') and
      (a1, a2) in (select c1, c2 from t3i
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0')));
 (select * from t1
 where (a1, a2) in (select b1, b2 from t2
                   where b2 in (select c2 from t3 where c2 LIKE '%02') or
                         b2 in (select c2 from t3 where c2 LIKE '%03')
                   group by b1, b2) and
      (a1, a2) in (select c1, c2 from t3
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0')))
 UNION
 (select * from t1i
 where (a1, a2) in (select b1, b2 from t2i where b1 >  '0') and
      (a1, a2) in (select c1, c2 from t3i
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0')));
 # UNION of subqueries as a subquery (thus it is not computed via materialization)
 explain extended
 select * from t1
 where (a1, a2) in (select * from t1 where a1 > '0' UNION select * from t2 where b1 < '9') and
      (a1, a2) in (select c1, c2 from t3
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
 select * from t1
 where (a1, a2) in (select * from t1 where a1 > '0' UNION select * from t2 where b1 < '9') and
      (a1, a2) in (select c1, c2 from t3
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
 # as above, with a join conditon between the outer references
 explain extended
 select * from t1, t3
 where (a1, a2) in (select * from t1 where a1 > '0' UNION select * from t2 where b1 < '9') and
      (c1, c2) in (select c1, c2 from t3
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0')) and
       a1 = c1;
 select * from t1, t3
 where (a1, a2) in (select * from t1 where a1 > '0' UNION select * from t2 where b1 < '9') and
      (c1, c2) in (select c1, c2 from t3
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0')) and
       a1 = c1;
 /******************************************************************************
 * Negative tests, where materialization should not be applied.
 ******************************************************************************/
 # UNION in a subquery
 explain extended
 select * from t3
 where c1 in (select a1 from t1 where a1 > '0' UNION select b1 from t2 where b1 < '9');
 select * from t3
 where c1 in (select a1 from t1 where a1 > '0' UNION select b1 from t2 where b1 < '9');
 # correlation
 explain extended
 select * from t1
 where (a1, a2) in (select b1, b2 from t2
                   where b2 in (select c2 from t3 t3a where c1 = a1) or
                         b2 in (select c2 from t3 t3b where c2 LIKE '%03')) and
      (a1, a2) in (select c1, c2 from t3 t3c
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0' or b2 = a2));
 # subquery has no tables
 explain extended
 select * from t1 where (a1, a2) in (select '1 - 01', '2 - 01');
 select * from t1 where (a1, a2) in (select '1 - 01', '2 - 01');
 explain extended
 select * from t1 where (a1, a2) in (select '1 - 01', '2 - 01' from dual);
 select * from t1 where (a1, a2) in (select '1 - 01', '2 - 01' from dual);
 /******************************************************************************
 * Subqueries in other uncovered clauses.
 ******************************************************************************/
 /* SELECT clause */
 select ((a1,a2) IN (select * from t2 where b2 > '0')) IS NULL from t1;
 /* GROUP BY clause */
 create table columns (col int key);
 insert into columns values (1), (2);
 explain extended
 select * from t1 group by (select col from columns limit 1);
 select * from t1 group by (select col from columns limit 1);
 explain extended
 select * from t1 group by (a1 in (select col from columns));
 select * from t1 group by (a1 in (select col from columns));
 /* ORDER BY clause */
 explain extended
 select * from t1 order by (select col from columns limit 1);
 select * from t1 order by (select col from columns limit 1);
 /******************************************************************************
 * Column types/sizes that affect materialization.
 ******************************************************************************/
 /*
  Test that BLOBs are not materialized (except when arguments of some functions).
 */
 # force materialization to be always considered
 set @@optimizer_switch='semijoin=off';
 set @prefix_len = 6;
 # BLOB == 16 (small blobs that could be stored in HEAP tables)
 set @blob_len = 16;
 set @suffix_len = @blob_len - @prefix_len;
 create table t1_16 (a1 blob(16), a2 blob(16));
 create table t2_16 (b1 blob(16), b2 blob(16));
 create table t3_16 (c1 blob(16), c2 blob(16));
 insert into t1_16 values
 (concat('1 - 00', repeat('x', @suffix_len)), concat('2 - 00', repeat('x', @suffix_len)));
 insert into t1_16 values
 (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
 insert into t1_16 values
 (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
 insert into t2_16 values
 (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
 insert into t2_16 values
 (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
 insert into t2_16 values
 (concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len)));
 insert into t3_16 values
 (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
 insert into t3_16 values
 (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
 insert into t3_16 values
 (concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len)));
 insert into t3_16 values
 (concat('1 - 04', repeat('x', @suffix_len)), concat('2 - 04', repeat('x', @suffix_len)));
 # single value transformer
 explain extended select left(a1,7), left(a2,7)
 from t1_16
 where a1 in (select b1 from t2_16 where b1 > '0');
 select left(a1,7), left(a2,7)
 from t1_16
 where a1 in (select b1 from t2_16 where b1 > '0');
 # row value transformer
 explain extended select left(a1,7), left(a2,7)
 from t1_16
 where (a1,a2) in (select b1, b2 from t2_16 where b1 > '0');
 select left(a1,7), left(a2,7)
 from t1_16
 where (a1,a2) in (select b1, b2 from t2_16 where b1 > '0');
 # string function with a blob argument, the return type may be != blob
 explain extended select left(a1,7), left(a2,7)
 from t1_16
 where a1 in (select substring(b1,1,16) from t2_16 where b1 > '0');
 select left(a1,7), left(a2,7)
 from t1_16
 where a1 in (select substring(b1,1,16) from t2_16 where b1 > '0');
 # group_concat with a blob argument - depends on
 # the variable group_concat_max_len, and
 # convert_blob_length == max_len*collation->mbmaxlen > CONVERT_IF_BIGGER_TO_BLOB
 explain extended select left(a1,7), left(a2,7)
 from t1_16
 where a1 in (select group_concat(b1) from t2_16 group by b2);
 select left(a1,7), left(a2,7)
 from t1_16
 where a1 in (select group_concat(b1) from t2_16 group by b2);
 set @@group_concat_max_len = 256; # anything < (CONVERT_IF_BIGGER_TO_BLOB = 512)
 explain extended select left(a1,7), left(a2,7)
 from t1_16
 where a1 in (select group_concat(b1) from t2_16 group by b2);
 select left(a1,7), left(a2,7)
 from t1_16
 where a1 in (select group_concat(b1) from t2_16 group by b2);
 # BLOB column at the second (intermediate) level of nesting
 explain extended
 select * from t1
 where concat(a1,'x') IN
      (select left(a1,8) from t1_16
       where (a1, a2) IN
             (select t2_16.b1, t2_16.b2 from t2_16, t2
              where t2.b2 = substring(t2_16.b2,1,6) and
                    t2.b1 IN (select c1 from t3 where c2 > '0')));
 drop table t1_16, t2_16, t3_16;
 # BLOB == 512 (CONVERT_IF_BIGGER_TO_BLOB == 512)
 set @blob_len = 512;
 set @suffix_len = @blob_len - @prefix_len;
 create table t1_512 (a1 blob(512), a2 blob(512));
 create table t2_512 (b1 blob(512), b2 blob(512));
 create table t3_512 (c1 blob(512), c2 blob(512));
 insert into t1_512 values
 (concat('1 - 00', repeat('x', @suffix_len)), concat('2 - 00', repeat('x', @suffix_len)));
 insert into t1_512 values
 (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
 insert into t1_512 values
 (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
 insert into t2_512 values
 (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
 insert into t2_512 values
 (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
 insert into t2_512 values
 (concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len)));
 insert into t3_512 values
 (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
 insert into t3_512 values
 (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
 insert into t3_512 values
 (concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len)));
 insert into t3_512 values
 (concat('1 - 04', repeat('x', @suffix_len)), concat('2 - 04', repeat('x', @suffix_len)));
 # single value transformer
 explain extended select left(a1,7), left(a2,7)
 from t1_512
 where a1 in (select b1 from t2_512 where b1 > '0');
 select left(a1,7), left(a2,7)
 from t1_512
 where a1 in (select b1 from t2_512 where b1 > '0');
 # row value transformer
 explain extended select left(a1,7), left(a2,7)
 from t1_512
 where (a1,a2) in (select b1, b2 from t2_512 where b1 > '0');
 select left(a1,7), left(a2,7)
 from t1_512
 where (a1,a2) in (select b1, b2 from t2_512 where b1 > '0');
 # string function with a blob argument, the return type may be != blob
 explain extended select left(a1,7), left(a2,7)
 from t1_512
 where a1 in (select substring(b1,1,512) from t2_512 where b1 > '0');
 select left(a1,7), left(a2,7)
 from t1_512
 where a1 in (select substring(b1,1,512) from t2_512 where b1 > '0');
 # group_concat with a blob argument - depends on
 # the variable group_concat_max_len, and
 # convert_blob_length == max_len*collation->mbmaxlen > CONVERT_IF_BIGGER_TO_BLOB
 explain extended select left(a1,7), left(a2,7)
 from t1_512
 where a1 in (select group_concat(b1) from t2_512 group by b2);
 select left(a1,7), left(a2,7)
 from t1_512
 where a1 in (select group_concat(b1) from t2_512 group by b2);
 set @@group_concat_max_len = 256; # anything < (CONVERT_IF_BIGGER_TO_BLOB = 512)
 explain extended select left(a1,7), left(a2,7)
 from t1_512
 where a1 in (select group_concat(b1) from t2_512 group by b2);
 select left(a1,7), left(a2,7)
 from t1_512
 where a1 in (select group_concat(b1) from t2_512 group by b2);
 drop table t1_512, t2_512, t3_512;
 # BLOB == 1024 (group_concat_max_len == 1024)
 set @blob_len = 1024;
 set @suffix_len = @blob_len - @prefix_len;
 create table t1_1024 (a1 blob(1024), a2 blob(1024));
 create table t2_1024 (b1 blob(1024), b2 blob(1024));
 create table t3_1024 (c1 blob(1024), c2 blob(1024));
 insert into t1_1024 values
 (concat('1 - 00', repeat('x', @suffix_len)), concat('2 - 00', repeat('x', @suffix_len)));
 insert into t1_1024 values
 (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
 insert into t1_1024 values
 (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
 insert into t2_1024 values
 (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
 insert into t2_1024 values
 (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
 insert into t2_1024 values
 (concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len)));
 insert into t3_1024 values
 (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
 insert into t3_1024 values
 (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
 insert into t3_1024 values
 (concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len)));
 insert into t3_1024 values
 (concat('1 - 04', repeat('x', @suffix_len)), concat('2 - 04', repeat('x', @suffix_len)));
 # single value transformer
 explain extended select left(a1,7), left(a2,7)
 from t1_1024
 where a1 in (select b1 from t2_1024 where b1 > '0');
 select left(a1,7), left(a2,7)
 from t1_1024
 where a1 in (select b1 from t2_1024 where b1 > '0');
 # row value transformer
 explain extended select left(a1,7), left(a2,7)
 from t1_1024
 where (a1,a2) in (select b1, b2 from t2_1024 where b1 > '0');
 select left(a1,7), left(a2,7)
 from t1_1024
 where (a1,a2) in (select b1, b2 from t2_1024 where b1 > '0');
 # string function with a blob argument, the return type may be != blob
 explain extended select left(a1,7), left(a2,7)
 from t1_1024
 where a1 in (select substring(b1,1,1024) from t2_1024 where b1 > '0');
 select left(a1,7), left(a2,7)
 from t1_1024
 where a1 in (select substring(b1,1,1024) from t2_1024 where b1 > '0');
 # group_concat with a blob argument - depends on
 # the variable group_concat_max_len, and
 # convert_blob_length == max_len*collation->mbmaxlen > CONVERT_IF_BIGGER_TO_BLOB
 explain extended select left(a1,7), left(a2,7)
 from t1_1024
 where a1 in (select group_concat(b1) from t2_1024 group by b2);
 select left(a1,7), left(a2,7)
 from t1_1024
 where a1 in (select group_concat(b1) from t2_1024 group by b2);
 set @@group_concat_max_len = 256; # anything < (CONVERT_IF_BIGGER_TO_BLOB = 1024)
 explain extended select left(a1,7), left(a2,7)
 from t1_1024
 where a1 in (select group_concat(b1) from t2_1024 group by b2);
 select left(a1,7), left(a2,7)
 from t1_1024
 where a1 in (select group_concat(b1) from t2_1024 group by b2);
 drop table t1_1024, t2_1024, t3_1024;
 # BLOB == 1025
 set @blob_len = 1025;
 set @suffix_len = @blob_len - @prefix_len;
 create table t1_1025 (a1 blob(1025), a2 blob(1025));
 create table t2_1025 (b1 blob(1025), b2 blob(1025));
 create table t3_1025 (c1 blob(1025), c2 blob(1025));
 insert into t1_1025 values
 (concat('1 - 00', repeat('x', @suffix_len)), concat('2 - 00', repeat('x', @suffix_len)));
 insert into t1_1025 values
 (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
 insert into t1_1025 values
 (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
 insert into t2_1025 values
 (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
 insert into t2_1025 values
 (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
 insert into t2_1025 values
 (concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len)));
 insert into t3_1025 values
 (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
 insert into t3_1025 values
 (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
 insert into t3_1025 values
 (concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len)));
 insert into t3_1025 values
 (concat('1 - 04', repeat('x', @suffix_len)), concat('2 - 04', repeat('x', @suffix_len)));
 # single value transformer
 explain extended select left(a1,7), left(a2,7)
 from t1_1025
 where a1 in (select b1 from t2_1025 where b1 > '0');
 select left(a1,7), left(a2,7)
 from t1_1025
 where a1 in (select b1 from t2_1025 where b1 > '0');
 # row value transformer
 explain extended select left(a1,7), left(a2,7)
 from t1_1025
 where (a1,a2) in (select b1, b2 from t2_1025 where b1 > '0');
 select left(a1,7), left(a2,7)
 from t1_1025
 where (a1,a2) in (select b1, b2 from t2_1025 where b1 > '0');
 # string function with a blob argument, the return type may be != blob
 explain extended select left(a1,7), left(a2,7)
 from t1_1025
 where a1 in (select substring(b1,1,1025) from t2_1025 where b1 > '0');
 select left(a1,7), left(a2,7)
 from t1_1025
 where a1 in (select substring(b1,1,1025) from t2_1025 where b1 > '0');
 # group_concat with a blob argument - depends on
 # the variable group_concat_max_len, and
 # convert_blob_length == max_len*collation->mbmaxlen > CONVERT_IF_BIGGER_TO_BLOB
 explain extended select left(a1,7), left(a2,7)
 from t1_1025
 where a1 in (select group_concat(b1) from t2_1025 group by b2);
 select left(a1,7), left(a2,7)
 from t1_1025
 where a1 in (select group_concat(b1) from t2_1025 group by b2);
 set @@group_concat_max_len = 256; # anything < (CONVERT_IF_BIGGER_TO_BLOB = 1025)
 explain extended select left(a1,7), left(a2,7)
 from t1_1025
 where a1 in (select group_concat(b1) from t2_1025 group by b2);
 select left(a1,7), left(a2,7)
 from t1_1025
 where a1 in (select group_concat(b1) from t2_1025 group by b2);
 drop table t1_1025, t2_1025, t3_1025;
 # test for BIT fields
 create table t1bit (a1 bit(3), a2 bit(3));
 create table t2bit (b1 bit(3), b2 bit(3));
 insert into t1bit values (b'000', b'100');
 insert into t1bit values (b'001', b'101');
 insert into t1bit values (b'010', b'110');
 insert into t2bit values (b'001', b'101');
 insert into t2bit values (b'010', b'110');
 insert into t2bit values (b'110', b'111');
 set @@optimizer_switch='semijoin=off';
 explain extended select bin(a1), bin(a2)
 from t1bit
 where (a1, a2) in (select b1, b2 from t2bit);
 select bin(a1), bin(a2)
 from t1bit
 where (a1, a2) in (select b1, b2 from t2bit);
 drop table t1bit, t2bit;
 # test mixture of BIT and BLOB
 create table t1bb (a1 bit(3), a2 blob(3));
 create table t2bb (b1 bit(3), b2 blob(3));
 insert into t1bb values (b'000', '100');
 insert into t1bb values (b'001', '101');
 insert into t1bb values (b'010', '110');
 insert into t2bb values (b'001', '101');
 insert into t2bb values (b'010', '110');
 insert into t2bb values (b'110', '111');
 explain extended select bin(a1), a2
 from t1bb
 where (a1, a2) in (select b1, b2 from t2bb);
 select bin(a1), a2
 from t1bb
 where (a1, a2) in (select b1, b2 from t2bb);
 drop table t1bb, t2bb;
 drop table t1, t2, t3, t1i, t2i, t3i, columns;
 /******************************************************************************
 * Test the cache of the left operand of IN.
 ******************************************************************************/
 set @@optimizer_switch='semijoin=off';
 # Test that default values of Cached_item are not used for comparison
 create table t1 (s1 int);
 create table t2 (s2 int);
 insert into t1 values (5),(1),(0);
 insert into t2 values (0), (1);
 select s2 from t2 where s2 in (select s1 from t1);
 drop table t1, t2;
 create table t1 (a int not null, b int not null);
 create table t2 (c int not null, d int not null);
 create table t3 (e int not null);
 # the first outer row has no matching inner row
 insert into t1 values (1,10);
 insert into t1 values (1,20);
 insert into t1 values (2,10);
 insert into t1 values (2,20);
 insert into t1 values (2,30);
 insert into t1 values (3,20);
 insert into t1 values (4,40);
 insert into t2 values (2,10);
 insert into t2 values (2,20);
 insert into t2 values (2,40);
 insert into t2 values (3,20);
 insert into t2 values (4,10);
 insert into t2 values (5,10);
 insert into t3 values (10);
 insert into t3 values (10);
 insert into t3 values (20);
 insert into t3 values (30);
 explain extended
 select a from t1 where a in (select c from t2 where d >= 20);
 select a from t1 where a in (select c from t2 where d >= 20);
 create index it1a on t1(a);
 explain extended
 select a from t1 where a in (select c from t2 where d >= 20);
 select a from t1 where a in (select c from t2 where d >= 20);
 # the first outer row has a matching inner row
 insert into t2 values (1,10);
 explain extended
 select a from t1 where a in (select c from t2 where d >= 20);
 select a from t1 where a in (select c from t2 where d >= 20);
 # cacheing for IN predicates inside a having clause - here the cached
 # items are changed to point to temporary tables.
 explain extended
 select a from t1 group by a having a in (select c from t2 where d >= 20);
 select a from t1 group by a having a in (select c from t2 where d >= 20);
 # create an index that can be used for the outer query GROUP BY 
 create index iab on t1(a, b);
 explain extended
 select a from t1 group by a having a in (select c from t2 where d >= 20);
 select a from t1 group by a having a in (select c from t2 where d >= 20);
 explain extended
 select a from t1 group by a
 having a in (select c from t2 where d >= some(select e from t3 where max(b)=e));
 select a from t1 group by a
 having a in (select c from t2 where d >= some(select e from t3 where max(b)=e));
 explain extended
 select a from t1
 where a in (select c from t2 where d >= some(select e from t3 where b=e));
 select a from t1
 where a in (select c from t2 where d >= some(select e from t3 where b=e));
 drop table t1, t2, t3;
 #
 # BUG#36133 "Assertion `exec_method != MATERIALIZATION || (exec_method == MATERIALIZATION &&"
 #
 create table t2 (a int, b int, key(a), key(b));
 insert into t2 values (3,3),(3,3),(3,3);
 select 1 from t2 where  
    t2.a > 1 
  or 
    t2.a = 3 and not t2.a not in (select t2.b from t2);
 drop table t2;
 #
 # BUG#37896 Assertion on entry of Item_in_subselect::exec on subquery with AND NOT
 #
 create table t1 (a1 int key);
 create table t2 (b1 int);
 insert into t1 values (5);
 # Query with group by, executed via materialization
 explain select min(a1) from t1 where 7 in (select b1 from t2 group by b1);
 select min(a1) from t1 where 7 in (select b1 from t2 group by b1);
 # Query with group by, executed via IN=>EXISTS
 set @@optimizer_switch='default,materialization=off';
 explain select min(a1) from t1 where 7 in (select b1 from t2 group by b1);
 select min(a1) from t1 where 7 in (select b1 from t2 group by b1);
 # Executed with materialization
 set @@optimizer_switch='default,semijoin=off';
 explain select min(a1) from t1 where 7 in (select b1 from t2);
 select min(a1) from t1 where 7 in (select b1 from t2);
 # Executed with semi-join. Notice, this time we get a different result (NULL).
 # This is the only correct result of all four queries. This difference is
 # filed as BUG#40037.
 set @@optimizer_switch='default,materialization=off';
 -- echo # with MariaDB and MWL#90, this particular case is solved:
 explain select min(a1) from t1 where 7 in (select b1 from t2);
 select min(a1) from t1 where 7 in (select b1 from t2);
 -- echo # but when we go around MWL#90 code, the problem still shows up:
 explain select min(a1) from t1 where 7 in (select b1 from t2) or 2> 4;
 select min(a1) from t1 where 7 in (select b1 from t2) or 2> 4;
 drop table t1,t2;
 #
 # BUG#36752 "subquery materialization produces wrong results when comparing different types"
 #
 create table t1 (a char(2), b varchar(10));
 insert into t1 values ('a',  'aaa');
 insert into t1 values ('aa', 'aaaa');
 set @@optimizer_switch='default,semijoin=off';
 explain select a,b from t1 where b in (select a from t1);
 select a,b from t1 where b in (select a from t1);
 prepare st1 from "select a,b from t1 where b in (select a from t1)";
 execute st1;
 execute st1;
 drop table t1;
 #
 # Bug #44303 Assertion failures in Field_new_decimal::store_decimal
 #            when executing materialized InsideOut semijoin
 # 
 CREATE TABLE t1 (f1 INT, f2 DECIMAL(5,3)) ENGINE=MyISAM;
 INSERT INTO t1 (f1, f2) VALUES (1, 1.789);
 INSERT INTO t1 (f1, f2) VALUES (13, 1.454);
 INSERT INTO t1 (f1, f2) VALUES (10, 1.668);
 CREATE TABLE t2 LIKE t1;
 INSERT INTO t2 VALUES (1, 1.789);
 INSERT INTO t2 VALUES (13, 1.454);
 SET @@optimizer_switch='default,semijoin=on,materialization=on';
 EXPLAIN SELECT COUNT(*) FROM t1 WHERE (f1,f2) IN (SELECT f1,f2 FROM t2);
 SELECT COUNT(*) FROM t1 WHERE (f1,f2) IN (SELECT f1,f2 FROM t2);
 DROP TABLE t1, t2;
 #
 # BUG#46548 IN-subqueries return 0 rows with materialization=on
 #
 CREATE TABLE t1 (
  pk int,
  a varchar(1),
  b varchar(4),
  c varchar(4),
  d varchar(4),
  PRIMARY KEY (pk)
 );
 INSERT INTO t1 VALUES (1,'o','ffff','ffff','ffoo'),(2,'f','ffff','ffff','ffff');
 CREATE TABLE t2 LIKE t1;
 INSERT INTO t2 VALUES (1,'i','iiii','iiii','iiii'),(2,'f','ffff','ffff','ffff');
 SET @@optimizer_switch='default,semijoin=on,materialization=on';
 EXPLAIN SELECT pk FROM t1 WHERE (a) IN (SELECT a FROM t2 WHERE pk > 0);
 SELECT pk FROM t1 WHERE (a) IN (SELECT a FROM t2 WHERE pk > 0);
 SELECT pk FROM t1 WHERE (b,c,d) IN (SELECT b,c,d FROM t2 WHERE pk > 0);
 DROP TABLE t1, t2;
 --echo #
 --echo # BUG#50019: Wrong result for IN-subquery with materialization
 --echo #
 create table t1(i int);
 insert into t1 values (1), (2), (3), (4), (5), (6), (7), (8), (9), (10);
 create table t2(i int);
 insert into t2 values (1), (2), (3), (4), (5), (6), (7), (8), (9), (10);
 create table t3(i int);
 insert into t3 values (1), (2), (3), (4), (5), (6), (7), (8), (9), (10);
 select * from t1 where t1.i in (select t2.i from t2 join t3 where t2.i + t3.i = 5);
 set @save_optimizer_switch=@@optimizer_switch;
 set session optimizer_switch='materialization=off';
 select * from t1 where t1.i in (select t2.i from t2 join t3 where t2.i + t3.i = 5);
 set session optimizer_switch=@save_optimizer_switch;
 drop table t1, t2, t3;
 #
 # Test that the contentes of the temp table of a materialized subquery is
 # cleanup up between PS reexecutions.
 #
 create table t0 (a int);
 insert into t0 values (0),(1),(2);
 create table t1 (a int);
 insert into t1 values (0),(1),(2);
 explain select a, a in (select a from t1) from t0;
 select a, a in (select a from t1) from t0;
 prepare s from 'select a, a in (select a from t1) from t0';
 execute s;
 update t1 set a=123;
 execute s;
 drop table t0, t1;
--- a/mysql-test/t/subselect_sj_mat.test
+++ b/mysql-test/t/subselect_sj_mat.test
@@ -0,0 +1,934 @@
 #
 # Hash semi-join regression tests
 # (WL#1110: Subquery optimization: materialization)
 #
 set optimizer_switch='firstmatch=off';
 --disable_warnings
 drop table if exists t1, t2, t3, t1i, t2i, t3i;
 drop view if exists v1, v2, v1m, v2m;
 --enable_warnings
 create table t1 (a1 char(8), a2 char(8));
 create table t2 (b1 char(8), b2 char(8));
 create table t3 (c1 char(8), c2 char(8));
 insert into t1 values ('1 - 00', '2 - 00');
 insert into t1 values ('1 - 01', '2 - 01');
 insert into t1 values ('1 - 02', '2 - 02');
 insert into t2 values ('1 - 01', '2 - 01');
 insert into t2 values ('1 - 01', '2 - 01');
 insert into t2 values ('1 - 02', '2 - 02');
 insert into t2 values ('1 - 02', '2 - 02');
 insert into t2 values ('1 - 03', '2 - 03');
 insert into t3 values ('1 - 01', '2 - 01');
 insert into t3 values ('1 - 02', '2 - 02');
 insert into t3 values ('1 - 03', '2 - 03');
 insert into t3 values ('1 - 04', '2 - 04');
 # Indexed columns
 create table t1i (a1 char(8), a2 char(8));
 create table t2i (b1 char(8), b2 char(8));
 create table t3i (c1 char(8), c2 char(8));
 create index it1i1 on t1i (a1);
 create index it1i2 on t1i (a2);
 create index it1i3 on t1i (a1, a2);
 create index it2i1 on t2i (b1);
 create index it2i2 on t2i (b2);
 create index it2i3 on t2i (b1, b2);
 create index it3i1 on t3i (c1);
 create index it3i2 on t3i (c2);
 create index it3i3 on t3i (c1, c2);
 insert into t1i select * from t1;
 insert into t2i select * from t2;
 insert into t3i select * from t3;
 /******************************************************************************
 * Simple tests.
 ******************************************************************************/
 # non-indexed nullable fields
 explain extended
 select * from t1 where a1 in (select b1 from t2 where b1 > '0');
 select * from t1 where a1 in (select b1 from t2 where b1 > '0');
 explain extended
 select * from t1 where a1 in (select b1 from t2 where b1 > '0' group by b1);
 select * from t1 where a1 in (select b1 from t2 where b1 > '0' group by b1);
 explain extended
 select * from t1 where (a1, a2) in (select b1, b2 from t2 where b1 > '0' group by b1, b2);
 select * from t1 where (a1, a2) in (select b1, b2 from t2 where b1 > '0' group by b1, b2);
 explain extended
 select * from t1 where (a1, a2) in (select b1, min(b2) from t2 where b1 > '0' group by b1);
 select * from t1 where (a1, a2) in (select b1, min(b2) from t2 where b1 > '0' group by b1);
 # indexed columns
 explain extended
 select * from t1i where a1 in (select b1 from t2i where b1 > '0');
 select * from t1i where a1 in (select b1 from t2i where b1 > '0');
 --replace_column 6 # 8 # 11 #
 explain extended
 select * from t1i where a1 in (select b1 from t2i where b1 > '0' group by b1);
 select * from t1i where a1 in (select b1 from t2i where b1 > '0' group by b1);
 explain extended
 select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0');
 select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0');
 --replace_column 6 # 7 # 8 # 11 #
 explain extended
 select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0' group by b1, b2);
 select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0' group by b1, b2);
 --replace_column 6 # 7 # 8 # 11 #
 explain extended
 select * from t1i where (a1, a2) in (select b1, min(b2) from t2i where b1 > '0' group by b1);
 select * from t1i where (a1, a2) in (select b1, min(b2) from t2i where b1 > '0' group by b1);
 # BUG#31639: Wrong plan for uncorrelated subquery when loose scan is applicable.
 explain extended
 select * from t1 where (a1, a2) in (select b1, max(b2) from t2i group by b1);
 select * from t1 where (a1, a2) in (select b1, max(b2) from t2i group by b1);
 prepare st1 from "explain select * from t1 where (a1, a2) in (select b1, max(b2) from t2i group by b1)";
 execute st1;
 execute st1;
 prepare st2 from "select * from t1 where (a1, a2) in (select b1, max(b2) from t2i group by b1)";
 execute st2;
 execute st2;
 explain extended
 select * from t1 where (a1, a2) in (select b1, min(b2) from t2i where b1 > '0' group by b1);
 select * from t1 where (a1, a2) in (select b1, min(b2) from t2i where b1 > '0' group by b1);
 -- error 1235
 select * from t1 where (a1, a2) in (select b1, min(b2) from t2i limit 1,1);
 # test re-optimization/re-execution with different execution methods
 # prepare once, exec with different modes
 set @save_optimizer_switch=@@optimizer_switch;
 set @@optimizer_switch='default,semijoin=off';
 prepare st1 from
 "select * from t1 where (a1, a2) in (select b1, min(b2) from t2 where b1 > '0' group by b1)";
 set @@optimizer_switch='default,materialization=off';
 execute st1;
 set @@optimizer_switch='default,semijoin=off';
 execute st1;
 set @@optimizer_switch='default,materialization=off';
 prepare st1 from
 "select * from t1 where (a1, a2) in (select b1, min(b2) from t2 where b1 > '0' group by b1)";
 set @@optimizer_switch='default,semijoin=off';
 execute st1;
 set @@optimizer_switch='default,materialization=off';
 execute st1;
 set @@optimizer_switch=@save_optimizer_switch;
 # materialize the result of ORDER BY
 # non-indexed fields
 explain extended
 select * from t1 where (a1, a2) in (select b1, b2 from t2 order by b1, b2);
 select * from t1 where (a1, a2) in (select b1, b2 from t2 order by b1, b2);
 # indexed fields
 explain extended
 select * from t1i where (a1, a2) in (select b1, b2 from t2i order by b1, b2);
 select * from t1i where (a1, a2) in (select b1, b2 from t2i order by b1, b2);
 /******************************************************************************
 * Views, UNIONs, several levels of nesting.
 ******************************************************************************/
 # materialize the result of subquery over temp-table view
 create algorithm=merge view v1 as
 select b1, c2 from t2, t3 where b2 > c2;
 create algorithm=merge view v2 as
 select b1, c2 from t2, t3 group by b2, c2;
 create algorithm=temptable view v1m as
 select b1, c2 from t2, t3 where b2 > c2;
 create algorithm=temptable view v2m as
 select b1, c2 from t2, t3 group by b2, c2;
 select * from v1 where (c2, b1) in (select c2, b1 from v2 where b1 is not null);
 select * from v1 where (c2, b1) in (select distinct c2, b1 from v2 where b1 is not null);
 select * from v1m where (c2, b1) in (select c2, b1 from v2m where b1 is not null);
 select * from v1m where (c2, b1) in (select distinct c2, b1 from v2m where b1 is not null);
 drop view v1, v2, v1m, v2m;
 # nested subqueries, views
 explain extended
 select * from t1
 where (a1, a2) in (select b1, b2 from t2 where b1 >  '0') and
      (a1, a2) in (select c1, c2 from t3
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
 select * from t1
 where (a1, a2) in (select b1, b2 from t2 where b1 >  '0') and
      (a1, a2) in (select c1, c2 from t3
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
 --replace_column 6 # 7 # 8 # 11 #
 explain extended
 select * from t1i
 where (a1, a2) in (select b1, b2 from t2i where b1 >  '0') and
      (a1, a2) in (select c1, c2 from t3i
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
 select * from t1i
 where (a1, a2) in (select b1, b2 from t2i where b1 >  '0') and
      (a1, a2) in (select c1, c2 from t3i
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
 explain extended
 select * from t1
 where (a1, a2) in (select b1, b2 from t2
                   where b2 in (select c2 from t3 where c2 LIKE '%02') or
                         b2 in (select c2 from t3 where c2 LIKE '%03')) and
      (a1, a2) in (select c1, c2 from t3
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
 select * from t1
 where (a1, a2) in (select b1, b2 from t2
                   where b2 in (select c2 from t3 where c2 LIKE '%02') or
                         b2 in (select c2 from t3 where c2 LIKE '%03')) and
      (a1, a2) in (select c1, c2 from t3
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
 # as above with correlated innermost subquery
 explain extended
 select * from t1
 where (a1, a2) in (select b1, b2 from t2
                   where b2 in (select c2 from t3 t3a where c1 = a1) or
                         b2 in (select c2 from t3 t3b where c2 LIKE '%03')) and
      (a1, a2) in (select c1, c2 from t3 t3c
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
 select * from t1
 where (a1, a2) in (select b1, b2 from t2
                   where b2 in (select c2 from t3 t3a where c1 = a1) or
                         b2 in (select c2 from t3 t3b where c2 LIKE '%03')) and
      (a1, a2) in (select c1, c2 from t3 t3c
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
 # multiple levels of nesting subqueries, unions
 --replace_column 6 # 7 # 8 # 11 #
 explain extended
 (select * from t1
 where (a1, a2) in (select b1, b2 from t2
                   where b2 in (select c2 from t3 where c2 LIKE '%02') or
                         b2 in (select c2 from t3 where c2 LIKE '%03')
                   group by b1, b2) and
      (a1, a2) in (select c1, c2 from t3
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0')))
 UNION
 (select * from t1i
 where (a1, a2) in (select b1, b2 from t2i where b1 >  '0') and
      (a1, a2) in (select c1, c2 from t3i
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0')));
 (select * from t1
 where (a1, a2) in (select b1, b2 from t2
                   where b2 in (select c2 from t3 where c2 LIKE '%02') or
                         b2 in (select c2 from t3 where c2 LIKE '%03')
                   group by b1, b2) and
      (a1, a2) in (select c1, c2 from t3
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0')))
 UNION
 (select * from t1i
 where (a1, a2) in (select b1, b2 from t2i where b1 >  '0') and
      (a1, a2) in (select c1, c2 from t3i
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0')));
 # UNION of subqueries as a subquery (thus it is not computed via materialization)
 explain extended
 select * from t1
 where (a1, a2) in (select * from t1 where a1 > '0' UNION select * from t2 where b1 < '9') and
      (a1, a2) in (select c1, c2 from t3
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
 select * from t1
 where (a1, a2) in (select * from t1 where a1 > '0' UNION select * from t2 where b1 < '9') and
      (a1, a2) in (select c1, c2 from t3
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
 # as above, with a join conditon between the outer references
 explain extended
 select * from t1, t3
 where (a1, a2) in (select * from t1 where a1 > '0' UNION select * from t2 where b1 < '9') and
      (c1, c2) in (select c1, c2 from t3
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0')) and
       a1 = c1;
 select * from t1, t3
 where (a1, a2) in (select * from t1 where a1 > '0' UNION select * from t2 where b1 < '9') and
      (c1, c2) in (select c1, c2 from t3
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0')) and
       a1 = c1;
 /******************************************************************************
 * Negative tests, where materialization should not be applied.
 ******************************************************************************/
 # UNION in a subquery
 explain extended
 select * from t3
 where c1 in (select a1 from t1 where a1 > '0' UNION select b1 from t2 where b1 < '9');
 select * from t3
 where c1 in (select a1 from t1 where a1 > '0' UNION select b1 from t2 where b1 < '9');
 # correlation
 explain extended
 select * from t1
 where (a1, a2) in (select b1, b2 from t2
                   where b2 in (select c2 from t3 t3a where c1 = a1) or
                         b2 in (select c2 from t3 t3b where c2 LIKE '%03')) and
      (a1, a2) in (select c1, c2 from t3 t3c
                   where (c1, c2) in (select b1, b2 from t2i where b2 > '0' or b2 = a2));
 # subquery has no tables
 explain extended
 select * from t1 where (a1, a2) in (select '1 - 01', '2 - 01');
 select * from t1 where (a1, a2) in (select '1 - 01', '2 - 01');
 explain extended
 select * from t1 where (a1, a2) in (select '1 - 01', '2 - 01' from dual);
 select * from t1 where (a1, a2) in (select '1 - 01', '2 - 01' from dual);
 /******************************************************************************
 * Subqueries in other uncovered clauses.
 ******************************************************************************/
 /* SELECT clause */
 select ((a1,a2) IN (select * from t2 where b2 > '0')) IS NULL from t1;
 /* GROUP BY clause */
 create table columns (col int key);
 insert into columns values (1), (2);
 explain extended
 select * from t1 group by (select col from columns limit 1);
 select * from t1 group by (select col from columns limit 1);
 explain extended
 select * from t1 group by (a1 in (select col from columns));
 select * from t1 group by (a1 in (select col from columns));
 /* ORDER BY clause */
 explain extended
 select * from t1 order by (select col from columns limit 1);
 select * from t1 order by (select col from columns limit 1);
 /******************************************************************************
 * Column types/sizes that affect materialization.
 ******************************************************************************/
 /*
  Test that BLOBs are not materialized (except when arguments of some functions).
 */
 # force materialization to be always considered
 set @prefix_len = 6;
 # BLOB == 16 (small blobs that could be stored in HEAP tables)
 set @blob_len = 16;
 set @suffix_len = @blob_len - @prefix_len;
 create table t1_16 (a1 blob(16), a2 blob(16));
 create table t2_16 (b1 blob(16), b2 blob(16));
 create table t3_16 (c1 blob(16), c2 blob(16));
 insert into t1_16 values
 (concat('1 - 00', repeat('x', @suffix_len)), concat('2 - 00', repeat('x', @suffix_len)));
 insert into t1_16 values
 (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
 insert into t1_16 values
 (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
 insert into t2_16 values
 (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
 insert into t2_16 values
 (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
 insert into t2_16 values
 (concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len)));
 insert into t3_16 values
 (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
 insert into t3_16 values
 (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
 insert into t3_16 values
 (concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len)));
 insert into t3_16 values
 (concat('1 - 04', repeat('x', @suffix_len)), concat('2 - 04', repeat('x', @suffix_len)));
 # single value transformer
 explain extended select left(a1,7), left(a2,7)
 from t1_16
 where a1 in (select b1 from t2_16 where b1 > '0');
 select left(a1,7), left(a2,7)
 from t1_16
 where a1 in (select b1 from t2_16 where b1 > '0');
 # row value transformer
 explain extended select left(a1,7), left(a2,7)
 from t1_16
 where (a1,a2) in (select b1, b2 from t2_16 where b1 > '0');
 select left(a1,7), left(a2,7)
 from t1_16
 where (a1,a2) in (select b1, b2 from t2_16 where b1 > '0');
 # string function with a blob argument, the return type may be != blob
 explain extended select left(a1,7), left(a2,7)
 from t1_16
 where a1 in (select substring(b1,1,16) from t2_16 where b1 > '0');
 select left(a1,7), left(a2,7)
 from t1_16
 where a1 in (select substring(b1,1,16) from t2_16 where b1 > '0');
 # group_concat with a blob argument - depends on
 # the variable group_concat_max_len, and
 # convert_blob_length == max_len*collation->mbmaxlen > CONVERT_IF_BIGGER_TO_BLOB
 explain extended select left(a1,7), left(a2,7)
 from t1_16
 where a1 in (select group_concat(b1) from t2_16 group by b2);
 select left(a1,7), left(a2,7)
 from t1_16
 where a1 in (select group_concat(b1) from t2_16 group by b2);
 set @@group_concat_max_len = 256; # anything < (CONVERT_IF_BIGGER_TO_BLOB = 512)
 explain extended select left(a1,7), left(a2,7)
 from t1_16
 where a1 in (select group_concat(b1) from t2_16 group by b2);
 select left(a1,7), left(a2,7)
 from t1_16
 where a1 in (select group_concat(b1) from t2_16 group by b2);
 # BLOB column at the second (intermediate) level of nesting
 explain extended
 select * from t1
 where concat(a1,'x') IN
      (select left(a1,8) from t1_16
       where (a1, a2) IN
             (select t2_16.b1, t2_16.b2 from t2_16, t2
              where t2.b2 = substring(t2_16.b2,1,6) and
                    t2.b1 IN (select c1 from t3 where c2 > '0')));
 drop table t1_16, t2_16, t3_16;
 # BLOB == 512 (CONVERT_IF_BIGGER_TO_BLOB == 512)
 set @blob_len = 512;
 set @suffix_len = @blob_len - @prefix_len;
 create table t1_512 (a1 blob(512), a2 blob(512));
 create table t2_512 (b1 blob(512), b2 blob(512));
 create table t3_512 (c1 blob(512), c2 blob(512));
 insert into t1_512 values
 (concat('1 - 00', repeat('x', @suffix_len)), concat('2 - 00', repeat('x', @suffix_len)));
 insert into t1_512 values
 (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
 insert into t1_512 values
 (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
 insert into t2_512 values
 (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
 insert into t2_512 values
 (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
 insert into t2_512 values
 (concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len)));
 insert into t3_512 values
 (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
 insert into t3_512 values
 (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
 insert into t3_512 values
 (concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len)));
 insert into t3_512 values
 (concat('1 - 04', repeat('x', @suffix_len)), concat('2 - 04', repeat('x', @suffix_len)));
 # single value transformer
 explain extended select left(a1,7), left(a2,7)
 from t1_512
 where a1 in (select b1 from t2_512 where b1 > '0');
 select left(a1,7), left(a2,7)
 from t1_512
 where a1 in (select b1 from t2_512 where b1 > '0');
 # row value transformer
 explain extended select left(a1,7), left(a2,7)
 from t1_512
 where (a1,a2) in (select b1, b2 from t2_512 where b1 > '0');
 select left(a1,7), left(a2,7)
 from t1_512
 where (a1,a2) in (select b1, b2 from t2_512 where b1 > '0');
 # string function with a blob argument, the return type may be != blob
 explain extended select left(a1,7), left(a2,7)
 from t1_512
 where a1 in (select substring(b1,1,512) from t2_512 where b1 > '0');
 select left(a1,7), left(a2,7)
 from t1_512
 where a1 in (select substring(b1,1,512) from t2_512 where b1 > '0');
 # group_concat with a blob argument - depends on
 # the variable group_concat_max_len, and
 # convert_blob_length == max_len*collation->mbmaxlen > CONVERT_IF_BIGGER_TO_BLOB
 explain extended select left(a1,7), left(a2,7)
 from t1_512
 where a1 in (select group_concat(b1) from t2_512 group by b2);
 select left(a1,7), left(a2,7)
 from t1_512
 where a1 in (select group_concat(b1) from t2_512 group by b2);
 set @@group_concat_max_len = 256; # anything < (CONVERT_IF_BIGGER_TO_BLOB = 512)
 explain extended select left(a1,7), left(a2,7)
 from t1_512
 where a1 in (select group_concat(b1) from t2_512 group by b2);
 select left(a1,7), left(a2,7)
 from t1_512
 where a1 in (select group_concat(b1) from t2_512 group by b2);
 drop table t1_512, t2_512, t3_512;
 # BLOB == 1024 (group_concat_max_len == 1024)
 set @blob_len = 1024;
 set @suffix_len = @blob_len - @prefix_len;
 create table t1_1024 (a1 blob(1024), a2 blob(1024));
 create table t2_1024 (b1 blob(1024), b2 blob(1024));
 create table t3_1024 (c1 blob(1024), c2 blob(1024));
 insert into t1_1024 values
 (concat('1 - 00', repeat('x', @suffix_len)), concat('2 - 00', repeat('x', @suffix_len)));
 insert into t1_1024 values
 (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
 insert into t1_1024 values
 (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
 insert into t2_1024 values
 (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
 insert into t2_1024 values
 (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
 insert into t2_1024 values
 (concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len)));
 insert into t3_1024 values
 (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
 insert into t3_1024 values
 (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
 insert into t3_1024 values
 (concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len)));
 insert into t3_1024 values
 (concat('1 - 04', repeat('x', @suffix_len)), concat('2 - 04', repeat('x', @suffix_len)));
 # single value transformer
 explain extended select left(a1,7), left(a2,7)
 from t1_1024
 where a1 in (select b1 from t2_1024 where b1 > '0');
 select left(a1,7), left(a2,7)
 from t1_1024
 where a1 in (select b1 from t2_1024 where b1 > '0');
 # row value transformer
 explain extended select left(a1,7), left(a2,7)
 from t1_1024
 where (a1,a2) in (select b1, b2 from t2_1024 where b1 > '0');
 select left(a1,7), left(a2,7)
 from t1_1024
 where (a1,a2) in (select b1, b2 from t2_1024 where b1 > '0');
 # string function with a blob argument, the return type may be != blob
 explain extended select left(a1,7), left(a2,7)
 from t1_1024
 where a1 in (select substring(b1,1,1024) from t2_1024 where b1 > '0');
 select left(a1,7), left(a2,7)
 from t1_1024
 where a1 in (select substring(b1,1,1024) from t2_1024 where b1 > '0');
 # group_concat with a blob argument - depends on
 # the variable group_concat_max_len, and
 # convert_blob_length == max_len*collation->mbmaxlen > CONVERT_IF_BIGGER_TO_BLOB
 explain extended select left(a1,7), left(a2,7)
 from t1_1024
 where a1 in (select group_concat(b1) from t2_1024 group by b2);
 select left(a1,7), left(a2,7)
 from t1_1024
 where a1 in (select group_concat(b1) from t2_1024 group by b2);
 set @@group_concat_max_len = 256; # anything < (CONVERT_IF_BIGGER_TO_BLOB = 1024)
 explain extended select left(a1,7), left(a2,7)
 from t1_1024
 where a1 in (select group_concat(b1) from t2_1024 group by b2);
 select left(a1,7), left(a2,7)
 from t1_1024
 where a1 in (select group_concat(b1) from t2_1024 group by b2);
 drop table t1_1024, t2_1024, t3_1024;
 # BLOB == 1025
 set @blob_len = 1025;
 set @suffix_len = @blob_len - @prefix_len;
 create table t1_1025 (a1 blob(1025), a2 blob(1025));
 create table t2_1025 (b1 blob(1025), b2 blob(1025));
 create table t3_1025 (c1 blob(1025), c2 blob(1025));
 insert into t1_1025 values
 (concat('1 - 00', repeat('x', @suffix_len)), concat('2 - 00', repeat('x', @suffix_len)));
 insert into t1_1025 values
 (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
 insert into t1_1025 values
 (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
 insert into t2_1025 values
 (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
 insert into t2_1025 values
 (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
 insert into t2_1025 values
 (concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len)));
 insert into t3_1025 values
 (concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
 insert into t3_1025 values
 (concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
 insert into t3_1025 values
 (concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len)));
 insert into t3_1025 values
 (concat('1 - 04', repeat('x', @suffix_len)), concat('2 - 04', repeat('x', @suffix_len)));
 # single value transformer
 explain extended select left(a1,7), left(a2,7)
 from t1_1025
 where a1 in (select b1 from t2_1025 where b1 > '0');
 select left(a1,7), left(a2,7)
 from t1_1025
 where a1 in (select b1 from t2_1025 where b1 > '0');
 # row value transformer
 explain extended select left(a1,7), left(a2,7)
 from t1_1025
 where (a1,a2) in (select b1, b2 from t2_1025 where b1 > '0');
 select left(a1,7), left(a2,7)
 from t1_1025
 where (a1,a2) in (select b1, b2 from t2_1025 where b1 > '0');
 # string function with a blob argument, the return type may be != blob
 explain extended select left(a1,7), left(a2,7)
 from t1_1025
 where a1 in (select substring(b1,1,1025) from t2_1025 where b1 > '0');
 select left(a1,7), left(a2,7)
 from t1_1025
 where a1 in (select substring(b1,1,1025) from t2_1025 where b1 > '0');
 # group_concat with a blob argument - depends on
 # the variable group_concat_max_len, and
 # convert_blob_length == max_len*collation->mbmaxlen > CONVERT_IF_BIGGER_TO_BLOB
 explain extended select left(a1,7), left(a2,7)
 from t1_1025
 where a1 in (select group_concat(b1) from t2_1025 group by b2);
 select left(a1,7), left(a2,7)
 from t1_1025
 where a1 in (select group_concat(b1) from t2_1025 group by b2);
 set @@group_concat_max_len = 256; # anything < (CONVERT_IF_BIGGER_TO_BLOB = 1025)
 explain extended select left(a1,7), left(a2,7)
 from t1_1025
 where a1 in (select group_concat(b1) from t2_1025 group by b2);
 select left(a1,7), left(a2,7)
 from t1_1025
 where a1 in (select group_concat(b1) from t2_1025 group by b2);
 drop table t1_1025, t2_1025, t3_1025;
 # test for BIT fields
 create table t1bit (a1 bit(3), a2 bit(3));
 create table t2bit (b1 bit(3), b2 bit(3));
 insert into t1bit values (b'000', b'100');
 insert into t1bit values (b'001', b'101');
 insert into t1bit values (b'010', b'110');
 insert into t2bit values (b'001', b'101');
 insert into t2bit values (b'010', b'110');
 insert into t2bit values (b'110', b'111');
 explain extended select bin(a1), bin(a2)
 from t1bit
 where (a1, a2) in (select b1, b2 from t2bit);
 select bin(a1), bin(a2)
 from t1bit
 where (a1, a2) in (select b1, b2 from t2bit);
 drop table t1bit, t2bit;
 # test mixture of BIT and BLOB
 create table t1bb (a1 bit(3), a2 blob(3));
 create table t2bb (b1 bit(3), b2 blob(3));
 insert into t1bb values (b'000', '100');
 insert into t1bb values (b'001', '101');
 insert into t1bb values (b'010', '110');
 insert into t2bb values (b'001', '101');
 insert into t2bb values (b'010', '110');
 insert into t2bb values (b'110', '111');
 explain extended select bin(a1), a2
 from t1bb
 where (a1, a2) in (select b1, b2 from t2bb);
 select bin(a1), a2
 from t1bb
 where (a1, a2) in (select b1, b2 from t2bb);
 drop table t1bb, t2bb;
 drop table t1, t2, t3, t1i, t2i, t3i, columns;
 /******************************************************************************
 * Test the cache of the left operand of IN.
 ******************************************************************************/
 # Test that default values of Cached_item are not used for comparison
 create table t1 (s1 int);
 create table t2 (s2 int);
 insert into t1 values (5),(1),(0);
 insert into t2 values (0), (1);
 select s2 from t2 where s2 in (select s1 from t1);
 drop table t1, t2;
 create table t1 (a int not null, b int not null);
 create table t2 (c int not null, d int not null);
 create table t3 (e int not null);
 # the first outer row has no matching inner row
 insert into t1 values (1,10);
 insert into t1 values (1,20);
 insert into t1 values (2,10);
 insert into t1 values (2,20);
 insert into t1 values (2,30);
 insert into t1 values (3,20);
 insert into t1 values (4,40);
 insert into t2 values (2,10);
 insert into t2 values (2,20);
 insert into t2 values (2,40);
 insert into t2 values (3,20);
 insert into t2 values (4,10);
 insert into t2 values (5,10);
 insert into t3 values (10);
 insert into t3 values (10);
 insert into t3 values (20);
 insert into t3 values (30);
 explain extended
 select a from t1 where a in (select c from t2 where d >= 20);
 select a from t1 where a in (select c from t2 where d >= 20);
 create index it1a on t1(a);
 explain extended
 select a from t1 where a in (select c from t2 where d >= 20);
 select a from t1 where a in (select c from t2 where d >= 20);
 # the first outer row has a matching inner row
 insert into t2 values (1,10);
 explain extended
 select a from t1 where a in (select c from t2 where d >= 20);
 select a from t1 where a in (select c from t2 where d >= 20);
 # cacheing for IN predicates inside a having clause - here the cached
 # items are changed to point to temporary tables.
 explain extended
 select a from t1 group by a having a in (select c from t2 where d >= 20);
 select a from t1 group by a having a in (select c from t2 where d >= 20);
 # create an index that can be used for the outer query GROUP BY 
 create index iab on t1(a, b);
 explain extended
 select a from t1 group by a having a in (select c from t2 where d >= 20);
 select a from t1 group by a having a in (select c from t2 where d >= 20);
 explain extended
 select a from t1 group by a
 having a in (select c from t2 where d >= some(select e from t3 where max(b)=e));
 select a from t1 group by a
 having a in (select c from t2 where d >= some(select e from t3 where max(b)=e));
 explain extended
 select a from t1
 where a in (select c from t2 where d >= some(select e from t3 where b=e));
 select a from t1
 where a in (select c from t2 where d >= some(select e from t3 where b=e));
 drop table t1, t2, t3;
 #
 # BUG#36133 "Assertion `exec_method != MATERIALIZATION || (exec_method == MATERIALIZATION &&"
 #
 create table t2 (a int, b int, key(a), key(b));
 insert into t2 values (3,3),(3,3),(3,3);
 select 1 from t2 where  
    t2.a > 1 
  or 
    t2.a = 3 and not t2.a not in (select t2.b from t2);
 drop table t2;
 #
 # BUG#37896 Assertion on entry of Item_in_subselect::exec on subquery with AND NOT
 #
 create table t1 (a1 int key);
 create table t2 (b1 int);
 insert into t1 values (5);
 # Query with group by, executed via materialization
 explain select min(a1) from t1 where 7 in (select b1 from t2 group by b1);
 select min(a1) from t1 where 7 in (select b1 from t2 group by b1);
 # Query with group by, executed via IN=>EXISTS
 set @save_optimizer_switch=@@optimizer_switch;
 set @@optimizer_switch='default,materialization=off';
 explain select min(a1) from t1 where 7 in (select b1 from t2 group by b1);
 select min(a1) from t1 where 7 in (select b1 from t2 group by b1);
 # Executed with materialization
 set @@optimizer_switch='default,semijoin=off';
 explain select min(a1) from t1 where 7 in (select b1 from t2);
 select min(a1) from t1 where 7 in (select b1 from t2);
 # Executed with semi-join. Notice, this time we get a different result (NULL).
 # This is the only correct result of all four queries. This difference is
 # filed as BUG#40037.
 set @@optimizer_switch='default,materialization=off';
 -- echo # with MariaDB and MWL#90, this particular case is solved:
 explain select min(a1) from t1 where 7 in (select b1 from t2);
 select min(a1) from t1 where 7 in (select b1 from t2);
 -- echo # but when we go around MWL#90 code, the problem still shows up:
 explain select min(a1) from t1 where 7 in (select b1 from t2) or 2> 4;
 select min(a1) from t1 where 7 in (select b1 from t2) or 2> 4;
 set @@optimizer_switch= @save_optimizer_switch;
 drop table t1,t2;
 #
 # BUG#36752 "subquery materialization produces wrong results when comparing different types"
 #
 create table t1 (a char(2), b varchar(10));
 insert into t1 values ('a',  'aaa');
 insert into t1 values ('aa', 'aaaa');
 explain select a,b from t1 where b in (select a from t1);
 select a,b from t1 where b in (select a from t1);
 prepare st1 from "select a,b from t1 where b in (select a from t1)";
 execute st1;
 execute st1;
 drop table t1;
 #
 # Bug #44303 Assertion failures in Field_new_decimal::store_decimal
 #            when executing materialized InsideOut semijoin
 # 
 CREATE TABLE t1 (f1 INT, f2 DECIMAL(5,3)) ENGINE=MyISAM;
 INSERT INTO t1 (f1, f2) VALUES (1, 1.789);
 INSERT INTO t1 (f1, f2) VALUES (13, 1.454);
 INSERT INTO t1 (f1, f2) VALUES (10, 1.668);
 CREATE TABLE t2 LIKE t1;
 INSERT INTO t2 VALUES (1, 1.789);
 INSERT INTO t2 VALUES (13, 1.454);
 set @save_optimizer_switch=@@optimizer_switch;
 SET @@optimizer_switch='default,semijoin=on,materialization=on';
 EXPLAIN SELECT COUNT(*) FROM t1 WHERE (f1,f2) IN (SELECT f1,f2 FROM t2);
 SELECT COUNT(*) FROM t1 WHERE (f1,f2) IN (SELECT f1,f2 FROM t2);
 set @@optimizer_switch= @save_optimizer_switch;
 DROP TABLE t1, t2;
 #
 # BUG#46548 IN-subqueries return 0 rows with materialization=on
 #
 CREATE TABLE t1 (
  pk int,
  a varchar(1),
  b varchar(4),
  c varchar(4),
  d varchar(4),
  PRIMARY KEY (pk)
 );
 INSERT INTO t1 VALUES (1,'o','ffff','ffff','ffoo'),(2,'f','ffff','ffff','ffff');
 CREATE TABLE t2 LIKE t1;
 INSERT INTO t2 VALUES (1,'i','iiii','iiii','iiii'),(2,'f','ffff','ffff','ffff');
 set @save_optimizer_switch=@@optimizer_switch;
 SET @@optimizer_switch='default,semijoin=on,materialization=on';
 EXPLAIN SELECT pk FROM t1 WHERE (a) IN (SELECT a FROM t2 WHERE pk > 0);
 SELECT pk FROM t1 WHERE (a) IN (SELECT a FROM t2 WHERE pk > 0);
 SELECT pk FROM t1 WHERE (b,c,d) IN (SELECT b,c,d FROM t2 WHERE pk > 0);
 DROP TABLE t1, t2;
 set optimizer_switch=@save_optimizer_switch;
 --echo #
 --echo # BUG#50019: Wrong result for IN-subquery with materialization
 --echo #
 create table t1(i int);
 insert into t1 values (1), (2), (3), (4), (5), (6), (7), (8), (9), (10);
 create table t2(i int);
 insert into t2 values (1), (2), (3), (4), (5), (6), (7), (8), (9), (10);
 create table t3(i int);
 insert into t3 values (1), (2), (3), (4), (5), (6), (7), (8), (9), (10);
 select * from t1 where t1.i in (select t2.i from t2 join t3 where t2.i + t3.i = 5);
 set @save_optimizer_switch=@@optimizer_switch;
 set session optimizer_switch='materialization=off';
 select * from t1 where t1.i in (select t2.i from t2 join t3 where t2.i + t3.i = 5);
 set session optimizer_switch=@save_optimizer_switch;
 drop table t1, t2, t3;
 #
 # Test that the contentes of the temp table of a materialized subquery is
 # cleanup up between PS reexecutions.
 #
 create table t0 (a int);
 insert into t0 values (0),(1),(2);
 create table t1 (a int);
 insert into t1 values (0),(1),(2);
 explain select a, a in (select a from t1) from t0;
 select a, a in (select a from t1) from t0;
 prepare s from 'select a, a in (select a from t1) from t0';
 execute s;
 update t1 set a=123;
 execute s;
 drop table t0, t1;
 set optimizer_switch='firstmatch=on';
--- a/sql-bench/test-table-elimination.sh
+++ b/sql-bench/test-table-elimination.sh
@@ -1,3 +1,4 @@
 #!@PERL@
 # Test of table elimination feature
--- a/sql/item_cmpfunc.cc
+++ b/sql/item_cmpfunc.cc
@@ -5761,32 +5761,27 @@ Item_field* Item_equal::get_first(Item_field *field)
  }
  else
  {
 #if 0    
    /*
      The field is not in SJ-Materialization nest. We must return the first
-      field that's not embedded in a SJ-Materialization nest.
+      field in the join order. The field may be inside a semi-join nest, i.e 
-      Example: suppose we have a join order:
+      a join order may look like this:
          SJ-Mat(it1  it2)  ot1  ot2
-      and equality ot2.col = ot1.col = it2.col
+      where we're looking what to substitute ot2.col for. In this case we must 
-      If we're looking for best substitute for 'ot2.col', we should pick ot1.col
+      still return it1.col, here's a proof why:
-      and not it2.col, because when we run a join between ot1 and ot2
+
-      execution of SJ-Mat(...) has already finished and we can't rely on the
+      First let's note that either it1.col or it2.col participates in 
-      value of it*.*.
+      subquery's IN-equality. It can't be otherwise, because materialization is
-      psergey-fix-fix: ^^ THAT IS INCORRECT ^^. Pick the first, whatever that
+      only applicable to uncorrelated subqueries, so the only way we could
-      is.
+      infer "it1.col=ot1.col" is from IN-equality. Ok, so IN-eqality has 
      it1.col or it2.col on its inner side. it1.col is first such item in the
      join order, so it's not possible for SJ-Mat to be
      SJ-Materialization-lookup, it is SJ-Materialization-Scan. The scan part
      of this strategy will unpack value of it1.col=it2.col into it1.col
      (that's the first equal item inside the subquery), and we'll be able to
      get it from there. qed.
    */
    while ((item= it++))
    {
      TABLE_LIST *emb_nest= item->field->table->pos_in_table_list->embedding;
      if (!emb_nest || !emb_nest->sj_mat_info || 
          !emb_nest->sj_mat_info->is_used)
      {
        return item;
      }
    }
 #endif
    return fields.head();
  }
  // Shouldn't get here.
--- a/sql/opt_subselect.cc
+++ b/sql/opt_subselect.cc
@@ -237,7 +237,8 @@ int check_and_do_in_subquery_rewrites(JOIN *join)
          with jtbm strategy
        */
        if (in_subs->exec_method == Item_in_subselect::MATERIALIZATION &&
-            thd->thd_marker.emb_on_expr_nest == (TABLE_LIST*)0x1)
+            thd->thd_marker.emb_on_expr_nest == (TABLE_LIST*)0x1 &&
            optimizer_flag(thd, OPTIMIZER_SWITCH_SEMIJOIN))
        {
          in_subs->emb_on_expr_nest= thd->thd_marker.emb_on_expr_nest;
          in_subs->is_flattenable_semijoin= FALSE;
--- a/sql/sql_select.cc
+++ b/sql/sql_select.cc
@@ -4287,7 +4287,6 @@ best_access_path(JOIN      *join,
  double tmp;
  ha_rows rec;
  bool best_uses_jbuf= FALSE;
  Item_in_subselect* jtbm_subselect= s->table->pos_in_table_list->jtbm_subselect;
  Loose_scan_opt loose_scan_opt;
  DBUG_ENTER("best_access_path");
@@ -4696,7 +4695,7 @@ best_access_path(JOIN      *join,
      !((s->table->file->ha_table_flags() & HA_TABLE_SCAN_ON_INDEX) &&   // (3)
        ! s->table->covering_keys.is_clear_all() && best_key && !s->quick) &&// (3)
      !(s->table->force_index && best_key && !s->quick) &&               // (4)
-      !(best_key && jtbm_subselect))                                     // (5)
+      !(best_key && s->table->pos_in_table_list->jtbm_subselect))        // (5)
  {                                             // Check full join
    ha_rows rnd_records= s->found_records;
    /*
`@@ -1,3 +1,4 @@`

	`#!@PERL@`	`#!@PERL@`
	`# Test of table elimination feature`	`# Test of table elimination feature`