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

- Merge into 5.3-subqueries
2025-08-07 00:04:31 +03:00 · 2010-05-24 15:24:20 +04:00
parent 64d505d42f 61864021ca
commit 5a53be655c
41 changed files with 1269 additions and 675 deletions
--- a/mysql-test/include/mix1.inc
+++ b/mysql-test/include/mix1.inc
@@ -1522,6 +1522,12 @@ INSERT INTO t1 VALUES (1,1,1), (1,1,1), (1,1,2), (1,1,1), (1,1,2);

 SELECT 1 FROM (SELECT COUNT(DISTINCT c1) 
                 FROM t1 WHERE c2 IN (1, 1) AND c3 = 2 GROUP BY c2) x;
+--echo # MariaDB note:
+--echo #  This will show 2 for table which has 5 rows. 
+--echo #  This is because the access method employed is actually range access
+--echo #  which scans 2 records (yes, EXPLAIN displays it incorrectly).
+--echo #  our correct printing is an artifact of changing in select_describe()
+--echo #  from printing table->starts.records() to tab->records.
 EXPLAIN 
 SELECT 1 FROM (SELECT COUNT(DISTINCT c1) 
                 FROM t1 WHERE c2 IN (1, 1) AND c3 = 2 GROUP BY c2) x;
@@ -1535,6 +1541,7 @@ INSERT INTO t1 VALUES (1,1,1), (1,1,1), (1,1,2), (1,1,1), (1,1,2);

 SELECT 1 FROM (SELECT COUNT(DISTINCT c1) 
                 FROM t1 WHERE c2 IN (1, 1) AND c3 = 2 GROUP BY c2) x;
+--echo # See above "MariaDB note"
 EXPLAIN 
 SELECT 1 FROM (SELECT COUNT(DISTINCT c1) 
                 FROM t1 WHERE c2 IN (1, 1) AND c3 = 2 GROUP BY c2) x;
@@ -1549,6 +1556,7 @@ INSERT INTO t1 VALUES (1,1,1), (1,1,1), (1,1,2), (1,1,1), (1,1,2);

 SELECT 1 FROM (SELECT COUNT(DISTINCT c1) 
                 FROM t1 WHERE c2 IN (1, 1) AND c3 = 2 GROUP BY c2) x;
+--echo # See above "MariaDB note"
 EXPLAIN 
 SELECT 1 FROM (SELECT COUNT(DISTINCT c1) 
                 FROM t1 WHERE c2 IN (1, 1) AND c3 = 2 GROUP BY c2) x;
--- a/mysql-test/r/group_min_max.result
+++ b/mysql-test/r/group_min_max.result
@@ -2255,7 +2255,8 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 EXPLAIN SELECT 1 FROM t1 AS t1_outer WHERE 
 a IN (SELECT max(b) FROM t1 GROUP BY a HAVING a < 2);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	t1_outer	index	NULL	a	10	NULL	15	Using where; Using index
+1	PRIMARY	SUBQUERY#2	ALL	distinct_key	NULL	NULL	NULL	8	
+1	PRIMARY	t1_outer	ref	a	a	5	SUBQUERY#2.max(b)	2	Using index
 2	SUBQUERY	t1	range	NULL	a	5	NULL	8	Using index for group-by
 EXPLAIN SELECT 1 FROM t1 AS t1_outer GROUP BY a HAVING 
 a > (SELECT max(b) FROM t1 GROUP BY a HAVING a < 2);
--- a/mysql-test/r/innodb_mysql.result
+++ b/mysql-test/r/innodb_mysql.result
@@ -1727,12 +1727,18 @@ SELECT 1 FROM (SELECT COUNT(DISTINCT c1)
 FROM t1 WHERE c2 IN (1, 1) AND c3 = 2 GROUP BY c2) x;
 1
 1
+# MariaDB note:
+#  This will show 2 for table which has 5 rows. 
+#  This is because the access method employed is actually range access
+#  which scans 2 records (yes, EXPLAIN displays it incorrectly).
+#  our correct printing is an artifact of changing in select_describe()
+#  from printing table->starts.records() to tab->records.
 EXPLAIN 
 SELECT 1 FROM (SELECT COUNT(DISTINCT c1) 
 FROM t1 WHERE c2 IN (1, 1) AND c3 = 2 GROUP BY c2) x;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	<derived2>	system	NULL	NULL	NULL	NULL	1	
-2	DERIVED	t1	index	c3,c2	c2	10	NULL	5	
+2	DERIVED	t1	index	c3,c2	c2	10	NULL	2	
 DROP TABLE t1;
 CREATE TABLE t1 (c1 REAL, c2 REAL, c3 REAL, KEY (c3), KEY (c2, c3))
 ENGINE=InnoDB;
@@ -1741,12 +1747,13 @@ SELECT 1 FROM (SELECT COUNT(DISTINCT c1)
 FROM t1 WHERE c2 IN (1, 1) AND c3 = 2 GROUP BY c2) x;
 1
 1
+# See above "MariaDB note"
 EXPLAIN 
 SELECT 1 FROM (SELECT COUNT(DISTINCT c1) 
 FROM t1 WHERE c2 IN (1, 1) AND c3 = 2 GROUP BY c2) x;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	<derived2>	system	NULL	NULL	NULL	NULL	1	
-2	DERIVED	t1	index	c3,c2	c2	18	NULL	5	
+2	DERIVED	t1	index	c3,c2	c2	18	NULL	2	
 DROP TABLE t1;
 CREATE TABLE t1 (c1 DECIMAL(12,2), c2 DECIMAL(12,2), c3 DECIMAL(12,2), 
 KEY (c3), KEY (c2, c3))
@@ -1756,12 +1763,13 @@ SELECT 1 FROM (SELECT COUNT(DISTINCT c1)
 FROM t1 WHERE c2 IN (1, 1) AND c3 = 2 GROUP BY c2) x;
 1
 1
+# See above "MariaDB note"
 EXPLAIN 
 SELECT 1 FROM (SELECT COUNT(DISTINCT c1) 
 FROM t1 WHERE c2 IN (1, 1) AND c3 = 2 GROUP BY c2) x;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	<derived2>	system	NULL	NULL	NULL	NULL	1	
-2	DERIVED	t1	index	c3,c2	c2	14	NULL	5	
+2	DERIVED	t1	index	c3,c2	c2	14	NULL	2	
 DROP TABLE t1;
 End of 5.1 tests
 drop table if exists t1, t2, t3;
--- a/mysql-test/r/metadata.result
+++ b/mysql-test/r/metadata.result
@@ -55,7 +55,7 @@ id	data	data
 2	female	no
 select t1.id from t1 union select t2.id from t2;
 Catalog	Database	Table	Table_alias	Column	Column_alias	Type	Length	Max length	Is_null	Flags	Decimals	Charsetnr
-def				id	id	1	4	1	Y	32768	0	63
+def				id	id	1	4	1	Y	49152	0	63
 id
 1
 2
@@ -66,7 +66,7 @@ insert into t1 values (2,'two');
 set @arg00=1 ;
 select @arg00 FROM t1 where a=1 union distinct select 1 FROM t1 where a=1;
 Catalog	Database	Table	Table_alias	Column	Column_alias	Type	Length	Max length	Is_null	Flags	Decimals	Charsetnr
-def				@arg00	@arg00	8	20	1	Y	32768	0	63
+def				@arg00	@arg00	8	20	1	Y	49152	0	63
@arg00
 1
 select * from (select @arg00) aaa;
@@ -76,7 +76,7 @@ def			aaa	@arg00	@arg00	8	20	1	Y	32768	0	63
 1
 select 1 union select 1;
 Catalog	Database	Table	Table_alias	Column	Column_alias	Type	Length	Max length	Is_null	Flags	Decimals	Charsetnr
-def				1	1	8	20	1	N	32769	0	63
+def				1	1	8	20	1	N	49153	0	63
 1
 1
 select * from (select 1 union select 1) aaa;
--- a/mysql-test/r/myisam_mrr.result
+++ b/mysql-test/r/myisam_mrr.result
@@ -347,7 +347,7 @@ GROUP BY t2.pk
 );
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE
-2	SUBQUERY	t2	ALL	int_key	int_key	5		3	33.33	Using index condition; Using filesort
+2	SUBQUERY	t2	ALL	int_key	int_key	5		0	0.00	Using index condition; Using filesort
 Warnings:
 Note	1003	select min(`test`.`t1`.`pk`) AS `MIN(t1.pk)` from `test`.`t1` where 0
 DROP TABLE t1, t2;
--- a/mysql-test/r/partition.result
+++ b/mysql-test/r/partition.result
@@ -1382,7 +1382,7 @@ NULL
 2
 explain partitions select * from t1 where a is null or a < 0 or a > 1;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	pn,p2	ALL	NULL	NULL	NULL	NULL	4	Using where
+1	SIMPLE	t1	pn,p2	ALL	NULL	NULL	NULL	NULL	2	Using where
 drop table t1;
 CREATE TABLE t1 (id INT NOT NULL PRIMARY KEY, name VARCHAR(20)) 
 ENGINE=MyISAM DEFAULT CHARSET=latin1
--- a/mysql-test/r/partition_hash.result
+++ b/mysql-test/r/partition_hash.result
@@ -69,25 +69,25 @@ id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	p0,p1,p2,p3	ALL	NULL	NULL	NULL	NULL	9	Using where
 explain partitions select * from t1 where a is null or (a >= 5 and a <= 7);
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0,p2,p3	ALL	NULL	NULL	NULL	NULL	9	Using where
+1	SIMPLE	t1	p0,p2,p3	ALL	NULL	NULL	NULL	NULL	7	Using where
 explain partitions select * from t1 where a is null;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	9	Using where
+1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	3	Using where
 explain partitions select * from t1 where a is not null;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	p0,p1,p2,p3	ALL	NULL	NULL	NULL	NULL	9	Using where
 explain partitions select * from t1 where a >= 1 and a < 3;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0,p1	ALL	NULL	NULL	NULL	NULL	9	Using where
+1	SIMPLE	t1	p0,p1	ALL	NULL	NULL	NULL	NULL	5	Using where
 explain partitions select * from t1 where a >= 3 and a <= 5;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p1,p2	ALL	NULL	NULL	NULL	NULL	9	Using where
+1	SIMPLE	t1	p1,p2	ALL	NULL	NULL	NULL	NULL	4	Using where
 explain partitions select * from t1 where a > 2 and a < 4;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p1	ALL	NULL	NULL	NULL	NULL	9	Using where
+1	SIMPLE	t1	p1	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where a > 3 and a <= 6;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p2,p3	ALL	NULL	NULL	NULL	NULL	9	Using where
+1	SIMPLE	t1	p2,p3	ALL	NULL	NULL	NULL	NULL	4	Using where
 explain partitions select * from t1 where a > 5;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	p0,p1,p2,p3	ALL	NULL	NULL	NULL	NULL	9	Using where
--- a/mysql-test/r/partition_pruning.result
+++ b/mysql-test/r/partition_pruning.result
--- a/mysql-test/r/partition_range.result
+++ b/mysql-test/r/partition_range.result
@@ -59,13 +59,13 @@ id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	pnull	system	NULL	NULL	NULL	NULL	1	
 explain partitions select * from t1 where a >= 0;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0,p1	ALL	NULL	NULL	NULL	NULL	3	Using where
+1	SIMPLE	t1	p0,p1	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where a < 0;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
 explain partitions select * from t1 where a <= 0;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	pnull,p0	ALL	NULL	NULL	NULL	NULL	3	Using where
+1	SIMPLE	t1	pnull,p0	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where a > 1;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
@@ -98,16 +98,16 @@ select * from t1 where a > 1;
 a	b
 explain partitions select * from t1 where a is null;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	pnull_pnullsp0,pnull_pnullsp1	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t1	pnull_pnullsp0,pnull_pnullsp1	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where a >= 0;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0_p0sp0,p0_p0sp1,p1_p1sp0,p1_p1sp1	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t1	p0_p0sp0,p0_p0sp1,p1_p1sp0,p1_p1sp1	ALL	NULL	NULL	NULL	NULL	4	Using where
 explain partitions select * from t1 where a < 0;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	pnull_pnullsp0,pnull_pnullsp1	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t1	pnull_pnullsp0,pnull_pnullsp1	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where a <= 0;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	pnull_pnullsp0,pnull_pnullsp1,p0_p0sp0,p0_p0sp1	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t1	pnull_pnullsp0,pnull_pnullsp1,p0_p0sp0,p0_p0sp1	ALL	NULL	NULL	NULL	NULL	4	Using where
 explain partitions select * from t1 where a > 1;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	NULL	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Impossible WHERE noticed after reading const tables
--- a/mysql-test/r/subselect.result
+++ b/mysql-test/r/subselect.result
@@ -3417,7 +3417,8 @@ 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	Using where
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	9	
+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);
@@ -3428,7 +3429,8 @@ 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	Using where
+1	PRIMARY	t1	ALL	a	NULL	NULL	NULL	9	
+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);
@@ -4322,16 +4324,18 @@ 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	Using where
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	2	100.00	
+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 `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 = `materialized subselect`.`1`)))))
+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)
 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	Using where
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	2	100.00	
+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 `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 = `materialized subselect`.`1`)))))
+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)
 DROP TABLE t1;
 #
 # Bug#45061: Incorrectly market field caused wrong result.
--- a/mysql-test/r/subselect3.result
+++ b/mysql-test/r/subselect3.result
@@ -1017,7 +1017,7 @@ update t22 set c = '2005-12-08 15:58:27' where a = 255;
 explain select t21.* from t21,t22 where t21.a = t22.a and 
 t22.a in (select t12.a from t11, t12 where t11.a in(255,256) and t11.a = t12.a and t11.c is null) and t22.c is null order by t21.a;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	subselect2	ALL	unique_key	NULL	NULL	NULL	8	Using temporary; Using filesort
+1	PRIMARY	SUBQUERY#2	ALL	unique_key	NULL	NULL	NULL	8	Using temporary; Using filesort
 1	PRIMARY	t21	ALL	NULL	NULL	NULL	NULL	26	Using where; Using join buffer
 1	PRIMARY	t22	ALL	NULL	NULL	NULL	NULL	26	Using where; Using join buffer
 2	SUBQUERY	t11	ALL	NULL	NULL	NULL	NULL	8	Using where
@@ -1035,7 +1035,7 @@ select (select max(Y.a) from t1 Y where a in (select a from t1 Z) and a < X.a) a
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	X	ALL	NULL	NULL	NULL	NULL	2	
 2	DEPENDENT SUBQUERY	Y	ALL	NULL	NULL	NULL	NULL	2	Using where
-2	DEPENDENT SUBQUERY	subselect3	eq_ref	unique_key	unique_key	5	func	1	
+2	DEPENDENT SUBQUERY	SUBQUERY#3	eq_ref	unique_key	unique_key	5	func	1	
 3	SUBQUERY	Z	ALL	NULL	NULL	NULL	NULL	2	
 select (select max(Y.a) from t1 Y where a in (select a from t1 Z) and a < X.a) as subq from t1 X;
 subq
@@ -1158,7 +1158,7 @@ create table t3 ( a int , filler char(100), key(a));
 insert into t3 select A.a + 10*B.a, 'filler' from t0 A, t0 B;
 explain select * from t3 where a in (select a from t2) and (a > 5 or a < 10);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	subselect2	ALL	unique_key	NULL	NULL	NULL	2	
+1	PRIMARY	SUBQUERY#2	ALL	unique_key	NULL	NULL	NULL	2	
 1	PRIMARY	t3	ref	a	a	5	test.t2.a	1	
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	2	Using where
 select * from t3 where a in (select a from t2);
@@ -1207,29 +1207,33 @@ insert into t3 select A.a + 10*B.a, A.a + 10*B.a, 'filler' from t1 A, t1 B, t1 C
 explain select * from t1, t3 where t3.a in (select a from t2) and (t3.a < 10 or t3.a >30) and t1.a =3;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	10	Using where
-1	PRIMARY	subselect2	ALL	unique_key	NULL	NULL	NULL	10	
+1	PRIMARY	SUBQUERY#2	ALL	unique_key	NULL	NULL	NULL	10	
 1	PRIMARY	t3	ref	a	a	5	test.t2.a	10	
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	10	Using where
 explain select straight_join * from t1 A, t1 B where A.a in (select a from t2);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	A	ALL	NULL	NULL	NULL	NULL	10	Using where
+1	PRIMARY	A	ALL	NULL	NULL	NULL	NULL	10	
 1	PRIMARY	B	ALL	NULL	NULL	NULL	NULL	10	Using join buffer
+1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	5	test.A.a	1	
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	10	
 explain select * from t2 where a in (select straight_join A.a from t1 A, t1 B);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	10	Using where
+1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	10	
+1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	5	test.t2.a	1	
 2	SUBQUERY	A	ALL	NULL	NULL	NULL	NULL	10	
 2	SUBQUERY	B	ALL	NULL	NULL	NULL	NULL	10	Using join buffer
 explain select * from t2 where a in (select straight_join A.a from t1 A, t1 B);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	10	Using where
+1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	10	
+1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	5	test.t2.a	1	
 2	SUBQUERY	A	ALL	NULL	NULL	NULL	NULL	10	
 2	SUBQUERY	B	ALL	NULL	NULL	NULL	NULL	10	Using join buffer
 explain select straight_join * from t2 X, t2 Y 
 where X.a in (select straight_join A.a from t1 A, t1 B);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	X	ALL	NULL	NULL	NULL	NULL	10	Using where
+1	PRIMARY	X	ALL	NULL	NULL	NULL	NULL	10	
 1	PRIMARY	Y	ALL	NULL	NULL	NULL	NULL	10	Using join buffer
+1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	5	test.X.a	1	
 2	SUBQUERY	A	ALL	NULL	NULL	NULL	NULL	10	
 2	SUBQUERY	B	ALL	NULL	NULL	NULL	NULL	10	Using join buffer
 create table t0 (a int, b int);
@@ -1237,14 +1241,14 @@ insert into t0 values(1,1);
 explain select * from t0, t3 where t3.a in (select a from t2) and (t3.a < 10 or t3.a >30);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t0	system	NULL	NULL	NULL	NULL	1	
-1	PRIMARY	subselect2	ALL	unique_key	NULL	NULL	NULL	10	
+1	PRIMARY	SUBQUERY#2	ALL	unique_key	NULL	NULL	NULL	10	
 1	PRIMARY	t3	ref	a	a	5	test.t2.a	10	
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	10	Using where
 create table t4 as select a as x, a as y from t1;
 explain select * from t0, t3 where (t3.a, t3.b) in (select x,y from t4) and (t3.a < 10 or t3.a >30);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t0	system	NULL	NULL	NULL	NULL	1	
-1	PRIMARY	subselect2	ALL	unique_key	NULL	NULL	NULL	10	
+1	PRIMARY	SUBQUERY#2	ALL	unique_key	NULL	NULL	NULL	10	
 1	PRIMARY	t3	ref	a	a	5	test.t4.x	10	Using where
 2	SUBQUERY	t4	ALL	NULL	NULL	NULL	NULL	10	Using where
 drop table t0,t1,t2,t3,t4;
@@ -1270,14 +1274,14 @@ set @@optimizer_switch='firstmatch=off';
 explain select * from t1 where (a,b) in (select a,b from t2);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	10	
-1	PRIMARY	subselect2	eq_ref	unique_key	unique_key	10	func	1	
+1	PRIMARY	SUBQUERY#2	eq_ref	unique_key	unique_key	10	func	1	
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	100	
 set @save_optimizer_search_depth=@@optimizer_search_depth;
 set @@optimizer_search_depth=63;
 explain select * from t1 where (a,b) in (select a,b from t2);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	10	
-1	PRIMARY	subselect2	eq_ref	unique_key	unique_key	10	func	1	
+1	PRIMARY	SUBQUERY#2	eq_ref	unique_key	unique_key	10	func	1	
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	100	
 set @@optimizer_search_depth=@save_optimizer_search_depth;
 set @@optimizer_switch=default;
@@ -1316,7 +1320,7 @@ insert into t2 select * from t2;
 explain select * from t1 where (a,b,c) in (select X.a, Y.a, Z.a from t2 X, t2 Y, t2 Z where X.b=33);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	
-1	PRIMARY	subselect2	eq_ref	unique_key	unique_key	15	func	1	
+1	PRIMARY	SUBQUERY#2	eq_ref	unique_key	unique_key	15	func	1	
 2	SUBQUERY	X	ALL	NULL	NULL	NULL	NULL	6	Using where
 2	SUBQUERY	Y	ALL	NULL	NULL	NULL	NULL	6	Using join buffer
 2	SUBQUERY	Z	ALL	NULL	NULL	NULL	NULL	6	Using join buffer
@@ -1389,7 +1393,7 @@ INNER JOIN t2 c ON c.idContact=cona.idContact
 WHERE cona.postalStripped='T2H3B2'
 	);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	subselect2	ALL	unique_key	NULL	NULL	NULL	2	1.00	
+1	PRIMARY	SUBQUERY#2	ALL	unique_key	NULL	NULL	NULL	2	1.00	
 1	PRIMARY	a	index	PRIMARY	PRIMARY	4	NULL	2	100.00	Using where; Using index; Using join buffer
 2	SUBQUERY	cona	ALL	NULL	NULL	NULL	NULL	2	100.00	Using where
 2	SUBQUERY	c	eq_ref	PRIMARY	PRIMARY	4	test.cona.idContact	1	100.00	
--- a/mysql-test/r/subselect3_jcl6.result
+++ b/mysql-test/r/subselect3_jcl6.result
@@ -1021,7 +1021,7 @@ update t22 set c = '2005-12-08 15:58:27' where a = 255;
 explain select t21.* from t21,t22 where t21.a = t22.a and 
 t22.a in (select t12.a from t11, t12 where t11.a in(255,256) and t11.a = t12.a and t11.c is null) and t22.c is null order by t21.a;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	subselect2	ALL	unique_key	NULL	NULL	NULL	8	Using temporary; Using filesort
+1	PRIMARY	SUBQUERY#2	ALL	unique_key	NULL	NULL	NULL	8	Using temporary; Using filesort
 1	PRIMARY	t21	ALL	NULL	NULL	NULL	NULL	26	Using where; Using join buffer
 1	PRIMARY	t22	ALL	NULL	NULL	NULL	NULL	26	Using where; Using join buffer
 2	SUBQUERY	t11	ALL	NULL	NULL	NULL	NULL	8	Using where
@@ -1040,7 +1040,7 @@ select (select max(Y.a) from t1 Y where a in (select a from t1 Z) and a < X.a) a
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	X	ALL	NULL	NULL	NULL	NULL	2	
 2	DEPENDENT SUBQUERY	Y	ALL	NULL	NULL	NULL	NULL	2	Using where
-2	DEPENDENT SUBQUERY	subselect3	eq_ref	unique_key	unique_key	5	func	1	
+2	DEPENDENT SUBQUERY	SUBQUERY#3	eq_ref	unique_key	unique_key	5	func	1	
 3	SUBQUERY	Z	ALL	NULL	NULL	NULL	NULL	2	
 select (select max(Y.a) from t1 Y where a in (select a from t1 Z) and a < X.a) as subq from t1 X;
 subq
@@ -1163,7 +1163,7 @@ create table t3 ( a int , filler char(100), key(a));
 insert into t3 select A.a + 10*B.a, 'filler' from t0 A, t0 B;
 explain select * from t3 where a in (select a from t2) and (a > 5 or a < 10);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	subselect2	ALL	unique_key	NULL	NULL	NULL	2	
+1	PRIMARY	SUBQUERY#2	ALL	unique_key	NULL	NULL	NULL	2	
 1	PRIMARY	t3	ref	a	a	5	test.t2.a	1	Using join buffer
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	2	Using where
 select * from t3 where a in (select a from t2);
@@ -1212,29 +1212,33 @@ insert into t3 select A.a + 10*B.a, A.a + 10*B.a, 'filler' from t1 A, t1 B, t1 C
 explain select * from t1, t3 where t3.a in (select a from t2) and (t3.a < 10 or t3.a >30) and t1.a =3;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	10	Using where
-1	PRIMARY	subselect2	ALL	unique_key	NULL	NULL	NULL	10	
+1	PRIMARY	SUBQUERY#2	ALL	unique_key	NULL	NULL	NULL	10	
 1	PRIMARY	t3	ref	a	a	5	test.t2.a	10	Using join buffer
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	10	Using where
 explain select straight_join * from t1 A, t1 B where A.a in (select a from t2);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	A	ALL	NULL	NULL	NULL	NULL	10	Using where
+1	PRIMARY	A	ALL	NULL	NULL	NULL	NULL	10	
 1	PRIMARY	B	ALL	NULL	NULL	NULL	NULL	10	Using join buffer
+1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	5	test.A.a	1	
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	10	
 explain select * from t2 where a in (select straight_join A.a from t1 A, t1 B);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	10	Using where
+1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	10	
+1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	5	test.t2.a	1	
 2	SUBQUERY	A	ALL	NULL	NULL	NULL	NULL	10	
 2	SUBQUERY	B	ALL	NULL	NULL	NULL	NULL	10	Using join buffer
 explain select * from t2 where a in (select straight_join A.a from t1 A, t1 B);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	10	Using where
+1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	10	
+1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	5	test.t2.a	1	
 2	SUBQUERY	A	ALL	NULL	NULL	NULL	NULL	10	
 2	SUBQUERY	B	ALL	NULL	NULL	NULL	NULL	10	Using join buffer
 explain select straight_join * from t2 X, t2 Y 
 where X.a in (select straight_join A.a from t1 A, t1 B);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	X	ALL	NULL	NULL	NULL	NULL	10	Using where
+1	PRIMARY	X	ALL	NULL	NULL	NULL	NULL	10	
 1	PRIMARY	Y	ALL	NULL	NULL	NULL	NULL	10	Using join buffer
+1	PRIMARY	SUBQUERY#2	eq_ref	distinct_key	distinct_key	5	test.X.a	1	
 2	SUBQUERY	A	ALL	NULL	NULL	NULL	NULL	10	
 2	SUBQUERY	B	ALL	NULL	NULL	NULL	NULL	10	Using join buffer
 create table t0 (a int, b int);
@@ -1242,14 +1246,14 @@ insert into t0 values(1,1);
 explain select * from t0, t3 where t3.a in (select a from t2) and (t3.a < 10 or t3.a >30);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t0	system	NULL	NULL	NULL	NULL	1	
-1	PRIMARY	subselect2	ALL	unique_key	NULL	NULL	NULL	10	
+1	PRIMARY	SUBQUERY#2	ALL	unique_key	NULL	NULL	NULL	10	
 1	PRIMARY	t3	ref	a	a	5	test.t2.a	10	Using join buffer
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	10	Using where
 create table t4 as select a as x, a as y from t1;
 explain select * from t0, t3 where (t3.a, t3.b) in (select x,y from t4) and (t3.a < 10 or t3.a >30);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t0	system	NULL	NULL	NULL	NULL	1	
-1	PRIMARY	subselect2	ALL	unique_key	NULL	NULL	NULL	10	
+1	PRIMARY	SUBQUERY#2	ALL	unique_key	NULL	NULL	NULL	10	
 1	PRIMARY	t3	ref	a	a	5	test.t4.x	10	Using where; Using join buffer
 2	SUBQUERY	t4	ALL	NULL	NULL	NULL	NULL	10	Using where
 drop table t0,t1,t2,t3,t4;
@@ -1275,14 +1279,14 @@ set @@optimizer_switch='firstmatch=off';
 explain select * from t1 where (a,b) in (select a,b from t2);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	10	
-1	PRIMARY	subselect2	eq_ref	unique_key	unique_key	10	func	1	
+1	PRIMARY	SUBQUERY#2	eq_ref	unique_key	unique_key	10	func	1	
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	100	
 set @save_optimizer_search_depth=@@optimizer_search_depth;
 set @@optimizer_search_depth=63;
 explain select * from t1 where (a,b) in (select a,b from t2);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	10	
-1	PRIMARY	subselect2	eq_ref	unique_key	unique_key	10	func	1	
+1	PRIMARY	SUBQUERY#2	eq_ref	unique_key	unique_key	10	func	1	
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	100	
 set @@optimizer_search_depth=@save_optimizer_search_depth;
 set @@optimizer_switch=default;
@@ -1321,7 +1325,7 @@ insert into t2 select * from t2;
 explain select * from t1 where (a,b,c) in (select X.a, Y.a, Z.a from t2 X, t2 Y, t2 Z where X.b=33);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	
-1	PRIMARY	subselect2	eq_ref	unique_key	unique_key	15	func	1	
+1	PRIMARY	SUBQUERY#2	eq_ref	unique_key	unique_key	15	func	1	
 2	SUBQUERY	X	ALL	NULL	NULL	NULL	NULL	6	Using where
 2	SUBQUERY	Y	ALL	NULL	NULL	NULL	NULL	6	Using join buffer
 2	SUBQUERY	Z	ALL	NULL	NULL	NULL	NULL	6	Using join buffer
@@ -1394,7 +1398,7 @@ INNER JOIN t2 c ON c.idContact=cona.idContact
 WHERE cona.postalStripped='T2H3B2'
 	);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
-1	PRIMARY	subselect2	ALL	unique_key	NULL	NULL	NULL	2	1.00	
+1	PRIMARY	SUBQUERY#2	ALL	unique_key	NULL	NULL	NULL	2	1.00	
 1	PRIMARY	a	index	PRIMARY	PRIMARY	4	NULL	2	100.00	Using where; Using index; Using join buffer
 2	SUBQUERY	cona	ALL	NULL	NULL	NULL	NULL	2	100.00	Using where
 2	SUBQUERY	c	eq_ref	PRIMARY	PRIMARY	4	test.cona.idContact	1	100.00	Using join buffer
--- a/mysql-test/r/subselect4.result
+++ b/mysql-test/r/subselect4.result
@@ -216,7 +216,7 @@ FROM t2
 WHERE PTYPE = 'Design'));
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t1	ALL	t1_IDX	NULL	NULL	NULL	5	
-1	PRIMARY	subselect2	eq_ref	unique_key	unique_key	3	func	1	
+1	PRIMARY	SUBQUERY#2	eq_ref	unique_key	unique_key	3	func	1	
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
 2	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	12	Using where; Using join buffer
 PREPARE stmt FROM "EXPLAIN SELECT EMPNAME
@@ -231,13 +231,13 @@ WHERE EMPNUM IN
 EXECUTE stmt;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t1	ALL	t1_IDX	NULL	NULL	NULL	5	
-1	PRIMARY	subselect2	eq_ref	unique_key	unique_key	3	func	1	
+1	PRIMARY	SUBQUERY#2	eq_ref	unique_key	unique_key	3	func	1	
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
 2	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	12	Using where; Using join buffer
 EXECUTE stmt;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	ALL	t1_IDX	NULL	NULL	NULL	5	
-1	SIMPLE	subselect2	eq_ref	unique_key	unique_key	3	func	1	
+1	SIMPLE	SUBQUERY#2	eq_ref	unique_key	unique_key	3	func	1	
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
 2	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	12	Using where; Using join buffer
 DEALLOCATE PREPARE stmt;
@@ -254,7 +254,7 @@ FROM t2
 WHERE PTYPE = 'Design'));
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t1	ALL	t1_IDX	NULL	NULL	NULL	5	
-1	PRIMARY	subselect2	eq_ref	unique_key	unique_key	3	func	1	
+1	PRIMARY	SUBQUERY#2	eq_ref	unique_key	unique_key	3	func	1	
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
 2	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	12	Using where; Using join buffer
 PREPARE stmt FROM "EXPLAIN SELECT EMPNAME
@@ -269,13 +269,13 @@ WHERE EMPNUM IN
 EXECUTE stmt;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t1	ALL	t1_IDX	NULL	NULL	NULL	5	
-1	PRIMARY	subselect2	eq_ref	unique_key	unique_key	3	func	1	
+1	PRIMARY	SUBQUERY#2	eq_ref	unique_key	unique_key	3	func	1	
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
 2	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	12	Using where; Using join buffer
 EXECUTE stmt;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	ALL	t1_IDX	NULL	NULL	NULL	5	
-1	SIMPLE	subselect2	eq_ref	unique_key	unique_key	3	func	1	
+1	SIMPLE	SUBQUERY#2	eq_ref	unique_key	unique_key	3	func	1	
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
 2	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	12	Using where; Using join buffer
 DEALLOCATE PREPARE stmt;
@@ -291,7 +291,7 @@ FROM t2
 WHERE PTYPE = 'Design'));
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	5	
-1	PRIMARY	subselect2	eq_ref	unique_key	unique_key	3	func	1	
+1	PRIMARY	SUBQUERY#2	eq_ref	unique_key	unique_key	3	func	1	
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
 2	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	12	Using where; Using join buffer
 PREPARE stmt FROM "EXPLAIN SELECT EMPNAME
@@ -306,13 +306,13 @@ WHERE EMPNUM IN
 EXECUTE stmt;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	5	
-1	PRIMARY	subselect2	eq_ref	unique_key	unique_key	3	func	1	
+1	PRIMARY	SUBQUERY#2	eq_ref	unique_key	unique_key	3	func	1	
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
 2	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	12	Using where; Using join buffer
 EXECUTE stmt;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	ALL	NULL	NULL	NULL	NULL	5	
-1	SIMPLE	subselect2	eq_ref	unique_key	unique_key	3	func	1	
+1	SIMPLE	SUBQUERY#2	eq_ref	unique_key	unique_key	3	func	1	
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	6	Using where
 2	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	12	Using where; Using join buffer
 DEALLOCATE PREPARE stmt;
--- a/mysql-test/r/subselect_mat.result
+++ b/mysql-test/r/subselect_mat.result
@@ -38,10 +38,11 @@ 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	Using where
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	
+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 `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` = `materialized subselect`.`b1`)))))
+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`)
 select * from t1 where a1 in (select b1 from t2 where b1 > '0');
 a1	a2
 1 - 01	2 - 01
@@ -49,10 +50,11 @@ 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	Using where
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	
+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 `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` = `materialized subselect`.`b1`)))))
+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`)
 select * from t1 where a1 in (select b1 from t2 where b1 > '0' group by b1);
 a1	a2
 1 - 01	2 - 01
@@ -60,10 +62,11 @@ 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	Using where
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	
+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 `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` = `materialized subselect`.`b1`) and (`test`.`t1`.`a2` = `materialized subselect`.`b2`)))))
+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`))
 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
@@ -71,10 +74,11 @@ 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	Using where
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	
+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 `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` = `materialized subselect`.`b1`) and (`test`.`t1`.`a2` = `materialized subselect`.`min(b2)`)))))
+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`))
 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
@@ -82,10 +86,11 @@ 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	NULL	it1i3	18	NULL	3	100.00	Using where; Using index
+1	PRIMARY	t1i	index	it1i1,it1i3	it1i3	18	NULL	3	100.00	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 `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` = `materialized subselect`.`b1`)))))
+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`)
 select * from t1i where a1 in (select b1 from t2i where b1 > '0');
 a1	a2
 1 - 01	2 - 01
@@ -93,10 +98,11 @@ 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	t1i	index	NULL	it1i3	18	NULL	3	100.00	Using where; Using index
-2	SUBQUERY	t2i	range	it2i1,it2i3	it2i1	9	NULL	3	100.00	Using where; Using index for group-by
+1	PRIMARY	SUBQUERY#2	ALL	distinct_key	#	NULL	#	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 `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` = `materialized subselect`.`b1`)))))
+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`)
 select * from t1i where a1 in (select b1 from t2i where b1 > '0' group by b1);
 a1	a2
 1 - 01	2 - 01
@@ -104,10 +110,11 @@ 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	NULL	it1i3	18	NULL	3	100.00	Using where; Using index
+1	PRIMARY	t1i	index	it1i1,it1i2,it1i3	it1i3	18	NULL	3	100.00	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 `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` = `materialized subselect`.`b1`) and (`test`.`t1i`.`a2` = `materialized subselect`.`b2`)))))
+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`))
 select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0');
 a1	a2
 1 - 01	2 - 01
@@ -115,10 +122,11 @@ 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	NULL	it1i3	18	NULL	3	100.00	Using where; Using index
-2	SUBQUERY	t2i	range	it2i1,it2i3	it2i3	18	NULL	3	100.00	Using where; Using index for group-by
+1	PRIMARY	t1i	index	it1i1,it1i2,it1i3	#	#	#	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 `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` = `materialized subselect`.`b1`) and (`test`.`t1i`.`a2` = `materialized subselect`.`b2`)))))
+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`))
 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
@@ -126,10 +134,11 @@ 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	NULL	it1i3	18	NULL	3	100.00	Using where; Using index
-2	SUBQUERY	t2i	range	it2i1,it2i3	it2i3	18	NULL	3	100.00	Using where; Using index for group-by
+1	PRIMARY	t1i	index	it1i1,it1i2,it1i3	#	#	#	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 `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` = `materialized subselect`.`b1`) and (`test`.`t1i`.`a2` = `materialized subselect`.`min(b2)`)))))
+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`))
 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
@@ -137,10 +146,11 @@ 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	Using where
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	
+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 `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` = `materialized subselect`.`b1`) and (`test`.`t1`.`a2` = `materialized subselect`.`max(b2)`)))))
+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`))
 select * from t1 where (a1, a2) in (select b1, max(b2) from t2i group by b1);
 a1	a2
 1 - 01	2 - 01
@@ -148,11 +158,13 @@ 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	Using where
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	
+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	Using where
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	
+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;
@@ -166,10 +178,11 @@ 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	Using where
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	
+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 `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` = `materialized subselect`.`b1`) and (`test`.`t1`.`a2` = `materialized subselect`.`min(b2)`)))))
+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`))
 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
@@ -206,10 +219,11 @@ set @@optimizer_switch='default,semijoin=off';
 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	Using where
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	
+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 `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` = `materialized subselect`.`b1`) and (`test`.`t1`.`a2` = `materialized subselect`.`b2`)))))
+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`))
 select * from t1 where (a1, a2) in (select b1, b2 from t2 order by b1, b2);
 a1	a2
 1 - 01	2 - 01
@@ -217,10 +231,11 @@ 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	NULL	it1i3	18	NULL	3	100.00	Using where; Using index
+1	PRIMARY	t1i	index	it1i1,it1i2,it1i3	it1i3	18	NULL	3	100.00	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 `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` = `materialized subselect`.`b1`) and (`test`.`t1i`.`a2` = `materialized subselect`.`b2`)))))
+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`))
 select * from t1i where (a1, a2) in (select b1, b2 from t2i order by b1, b2);
 a1	a2
 1 - 01	2 - 01
@@ -270,12 +285,15 @@ 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	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
-3	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	4	100.00	Using where
+1	PRIMARY	SUBQUERY#2	ALL	distinct_key	NULL	NULL	NULL	5	0.00	
+1	PRIMARY	SUBQUERY#3	eq_ref	distinct_key	distinct_key	18	SUBQUERY#2.b1,SUBQUERY#2.b2	1	100.00	
+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 `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` = `materialized subselect`.`b1`) and (`test`.`t1`.`a2` = `materialized subselect`.`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` = `materialized subselect`.`b1`) and (`test`.`t3`.`c2` = `materialized subselect`.`b2`))))) ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key where ((`test`.`t1`.`a1` = `materialized subselect`.`c1`) and (`test`.`t1`.`a2` = `materialized subselect`.`c2`))))))
+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`))
 select * from t1
 where (a1, a2) in (select b1, b2 from t2 where b1 >  '0') and
 (a1, a2) in (select c1, c2 from t3
@@ -289,12 +307,15 @@ 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	t1i	index	NULL	it1i3	18	NULL	3	100.00	Using where; Using index
-3	SUBQUERY	t3i	index	NULL	it3i3	18	NULL	4	100.00	Using where; Using index
-4	SUBQUERY	t2i	index	it2i2	it2i3	18	NULL	5	100.00	Using where; Using index
-2	SUBQUERY	t2i	index	it2i1,it2i3	it2i3	18	NULL	5	100.00	Using where; Using index
+1	PRIMARY	SUBQUERY#2	ALL	distinct_key	#	#	#	5	0.00	#
+1	PRIMARY	SUBQUERY#3	eq_ref	distinct_key	#	#	#	1	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 `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` = `materialized subselect`.`b1`) and (`test`.`t1i`.`a2` = `materialized subselect`.`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` = `materialized subselect`.`b1`) and (`test`.`t3i`.`c2` = `materialized subselect`.`b2`))))) ), <primary_index_lookup>(`test`.`t1i`.`a1` in <temporary table> on distinct_key where ((`test`.`t1i`.`a1` = `materialized subselect`.`c1`) and (`test`.`t1i`.`a2` = `materialized subselect`.`c2`))))))
+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`))
 select * from t1i
 where (a1, a2) in (select b1, b2 from t2i where b1 >  '0') and
 (a1, a2) in (select c1, c2 from t3i
@@ -310,14 +331,17 @@ 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	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
-5	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	4	100.00	Using where
+1	PRIMARY	SUBQUERY#2	ALL	distinct_key	NULL	NULL	NULL	5	0.00	
+1	PRIMARY	SUBQUERY#5	eq_ref	distinct_key	distinct_key	18	SUBQUERY#2.b1,SUBQUERY#2.b2	1	100.00	
+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 `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` = `materialized subselect`.`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` = `materialized subselect`.`c2`)))))) ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key where ((`test`.`t1`.`a1` = `materialized subselect`.`b1`) and (`test`.`t1`.`a2` = `materialized subselect`.`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` = `materialized subselect`.`b1`) and (`test`.`t3`.`c2` = `materialized subselect`.`b2`))))) ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key where ((`test`.`t1`.`a1` = `materialized subselect`.`c1`) and (`test`.`t1`.`a2` = `materialized subselect`.`c2`))))))
+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`))
 select * from t1
 where (a1, a2) in (select b1, b2 from t2
 where b2 in (select c2 from t3 where c2 LIKE '%02') or
@@ -335,14 +359,16 @@ 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
-5	SUBQUERY	t3c	ALL	NULL	NULL	NULL	NULL	4	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	
+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 `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` = `materialized subselect`.`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` = `materialized subselect`.`b1`) and (`test`.`t3c`.`c2` = `materialized subselect`.`b2`))))) ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key where ((`test`.`t1`.`a1` = `materialized subselect`.`c1`) and (`test`.`t1`.`a2` = `materialized subselect`.`c2`))))))
+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`)))))
 select * from t1
 where (a1, a2) in (select b1, b2 from t2
 where b2 in (select c2 from t3 t3a where c1 = a1) or
@@ -366,19 +392,25 @@ 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	t1	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
-5	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	4	100.00	Using where
-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; Using temporary; Using filesort
-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
-7	UNION	t1i	index	NULL	it1i3	18	NULL	3	100.00	Using where; Using index
-9	SUBQUERY	t3i	index	NULL	it3i3	18	NULL	4	100.00	Using where; Using index
-10	SUBQUERY	t2i	index	it2i2	it2i3	18	NULL	5	100.00	Using where; Using index
-8	SUBQUERY	t2i	index	it2i1,it2i3	it2i3	18	NULL	5	100.00	Using where; Using index
-NULL	UNION RESULT	<union1,7>	ALL	NULL	NULL	NULL	NULL	NULL	NULL	
+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	SUBQUERY#9	eq_ref	distinct_key	#	#	#	1	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 `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` = `materialized subselect`.`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` = `materialized subselect`.`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` = `materialized subselect`.`b1`) and (`test`.`t1`.`a2` = `materialized subselect`.`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` = `materialized subselect`.`b1`) and (`test`.`t3`.`c2` = `materialized subselect`.`b2`))))) ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key where ((`test`.`t1`.`a1` = `materialized subselect`.`c1`) and (`test`.`t1`.`a2` = `materialized subselect`.`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` = `materialized subselect`.`b1`) and (`test`.`t1i`.`a2` = `materialized subselect`.`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` = `materialized subselect`.`b1`) and (`test`.`t3i`.`c2` = `materialized subselect`.`b2`))))) ), <primary_index_lookup>(`test`.`t1i`.`a1` in <temporary table> on distinct_key where ((`test`.`t1i`.`a1` = `materialized subselect`.`c1`) and (`test`.`t1i`.`a2` = `materialized subselect`.`c2`)))))))
+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`)))
 (select * from t1
 where (a1, a2) in (select b1, b2 from t2
 where b2 in (select c2 from t3 where c2 LIKE '%02') or
@@ -401,13 +433,15 @@ 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
-4	SUBQUERY	t3	ALL	NULL	NULL	NULL	NULL	4	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	
+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 `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` = `materialized subselect`.`b1`) and (`test`.`t3`.`c2` = `materialized subselect`.`b2`))))) ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key where ((`test`.`t1`.`a1` = `materialized subselect`.`c1`) and (`test`.`t1`.`a2` = `materialized subselect`.`c2`))))))
+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`)))))
 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
@@ -423,14 +457,16 @@ 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	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`,`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` = `materialized subselect`.`b1`) and (`test`.`t3`.`c2` = `materialized subselect`.`b2`))))) ), <primary_index_lookup>(`test`.`t3`.`c1` in <temporary table> on distinct_key where ((`test`.`t3`.`c1` = `materialized subselect`.`c1`) and (`test`.`t3`.`c2` = `materialized subselect`.`c2`))))))
+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`)))))
 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
@@ -476,7 +512,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 Warnings:
 Note	1276	Field or reference 'test.t1.a1' of SELECT #3 was resolved in SELECT #1
 Note	1276	Field or reference 'test.t1.a2' of SELECT #6 was resolved in SELECT #1
-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` = `materialized subselect`.`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`),<exists>(select `test`.`t3c`.`c1` AS `c1`,`test`.`t3c`.`c2` AS `c2` from `test`.`t3` `t3c` where (<in_optimizer>((`test`.`t3c`.`c1`,`test`.`t3c`.`c2`),<exists>(<index_lookup>(<cache>(`test`.`t3c`.`c1`) in t2i on it2i3 where (((`test`.`t2i`.`b2` > '0') or (`test`.`t2i`.`b2` = `test`.`t1`.`a2`)) and (<cache>(`test`.`t3c`.`c1`) = `test`.`t2i`.`b1`) and (<cache>(`test`.`t3c`.`c2`) = `test`.`t2i`.`b2`))))) and (<cache>(`test`.`t1`.`a1`) = `test`.`t3c`.`c1`) and (<cache>(`test`.`t1`.`a2`) = `test`.`t3c`.`c2`)))))
+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`),<exists>(select `test`.`t3c`.`c1` AS `c1`,`test`.`t3c`.`c2` AS `c2` from `test`.`t3` `t3c` where (<in_optimizer>((`test`.`t3c`.`c1`,`test`.`t3c`.`c2`),<exists>(<index_lookup>(<cache>(`test`.`t3c`.`c1`) in t2i on it2i3 where (((`test`.`t2i`.`b2` > '0') or (`test`.`t2i`.`b2` = `test`.`t1`.`a2`)) and (<cache>(`test`.`t3c`.`c1`) = `test`.`t2i`.`b1`) and (<cache>(`test`.`t3c`.`c2`) = `test`.`t2i`.`b2`))))) and (<cache>(`test`.`t1`.`a1`) = `test`.`t3c`.`c1`) and (<cache>(`test`.`t1`.`a2`) = `test`.`t3c`.`c2`)))))
 explain extended
 select * from t1 where (a1, a2) in (select '1 - 01', '2 - 01');
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
@@ -608,10 +644,11 @@ 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	Using where
+1	PRIMARY	t1_16	ALL	NULL	NULL	NULL	NULL	3	100.00	
+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 `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` = `materialized subselect`.`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  <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)`)
 select left(a1,7), left(a2,7)
 from t1_16
 where a1 in (select substring(b1,1,16) from t2_16 where b1 > '0');
@@ -637,10 +674,11 @@ 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	Using where
+1	PRIMARY	t1_16	ALL	NULL	NULL	NULL	NULL	3	100.00	
+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 `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` = `materialized subselect`.`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  <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)`)
 select left(a1,7), left(a2,7)
 from t1_16
 where a1 in (select group_concat(b1) from t2_16 group by b2);
@@ -660,9 +698,10 @@ 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 `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` = `materialized subselect`.`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)))))
+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)))))
 drop table t1_16, t2_16, t3_16;
 set @blob_len = 512;
 set @suffix_len = @blob_len - @prefix_len;
@@ -721,10 +760,11 @@ 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	Using where
+1	PRIMARY	t1_512	ALL	NULL	NULL	NULL	NULL	3	100.00	
+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 `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` = `materialized subselect`.`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  <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)`)
 select left(a1,7), left(a2,7)
 from t1_512
 where a1 in (select substring(b1,1,512) from t2_512 where b1 > '0');
@@ -735,10 +775,11 @@ 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	Using where
+1	PRIMARY	t1_512	ALL	NULL	NULL	NULL	NULL	3	100.00	
+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 `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` = `materialized subselect`.`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  <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)`)
 select left(a1,7), left(a2,7)
 from t1_512
 where a1 in (select group_concat(b1) from t2_512 group by b2);
@@ -748,10 +789,11 @@ 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	Using where
+1	PRIMARY	t1_512	ALL	NULL	NULL	NULL	NULL	3	100.00	
+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 `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` = `materialized subselect`.`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  <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)`)
 select left(a1,7), left(a2,7)
 from t1_512
 where a1 in (select group_concat(b1) from t2_512 group by b2);
@@ -817,7 +859,7 @@ 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`,`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)))))
+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))))
 select left(a1,7), left(a2,7)
 from t1_1024
 where a1 in (select substring(b1,1,1024) from t2_1024 where b1 > '0');
@@ -828,10 +870,11 @@ 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	Using where
+1	PRIMARY	t1_1024	ALL	NULL	NULL	NULL	NULL	3	100.00	
+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 `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` = `materialized subselect`.`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  <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)`)
 select left(a1,7), left(a2,7)
 from t1_1024
 where a1 in (select group_concat(b1) from t2_1024 group by b2);
@@ -841,10 +884,11 @@ 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	Using where
+1	PRIMARY	t1_1024	ALL	NULL	NULL	NULL	NULL	3	100.00	
+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 `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` = `materialized subselect`.`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  <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)`)
 select left(a1,7), left(a2,7)
 from t1_1024
 where a1 in (select group_concat(b1) from t2_1024 group by b2);
@@ -910,7 +954,7 @@ 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`,`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)))))
+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))))
 select left(a1,7), left(a2,7)
 from t1_1025
 where a1 in (select substring(b1,1,1025) from t2_1025 where b1 > '0');
@@ -921,10 +965,11 @@ 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	Using where
+1	PRIMARY	t1_1025	ALL	NULL	NULL	NULL	NULL	3	100.00	
+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 `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` = `materialized subselect`.`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  <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)`)
 select left(a1,7), left(a2,7)
 from t1_1025
 where a1 in (select group_concat(b1) from t2_1025 group by b2);
@@ -934,10 +979,11 @@ 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	Using where
+1	PRIMARY	t1_1025	ALL	NULL	NULL	NULL	NULL	3	100.00	
+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 `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` = `materialized subselect`.`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  <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)`)
 select left(a1,7), left(a2,7)
 from t1_1025
 where a1 in (select group_concat(b1) from t2_1025 group by b2);
@@ -956,10 +1002,11 @@ 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	Using where
+1	PRIMARY	t1bit	ALL	NULL	NULL	NULL	NULL	3	100.00	
+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 `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` = `materialized subselect`.`b1`) and (`test`.`t1bit`.`a2` = `materialized subselect`.`b2`)))))
+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`))
 select bin(a1), bin(a2)
 from t1bit
 where (a1, a2) in (select b1, b2 from t2bit);
@@ -1027,10 +1074,11 @@ 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	Using where
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	7	100.00	
+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 `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` = `materialized subselect`.`c`)))))
+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`)
 select a from t1 where a in (select c from t2 where d >= 20);
 a
 2
@@ -1041,10 +1089,11 @@ 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	NULL	it1a	4	NULL	7	100.00	Using where; Using index
+1	PRIMARY	t1	index	it1a	it1a	4	NULL	7	100.00	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 `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` = `materialized subselect`.`c`)))))
+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`)
 select a from t1 where a in (select c from t2 where d >= 20);
 a
 2
@@ -1055,10 +1104,11 @@ 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	NULL	it1a	4	NULL	7	100.00	Using where; Using index
+1	PRIMARY	t1	index	it1a	it1a	4	NULL	7	100.00	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 `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` = `materialized subselect`.`c`)))))
+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`)
 select a from t1 where a in (select c from t2 where d >= 20);
 a
 2
@@ -1071,7 +1121,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	t1	index	NULL	it1a	4	NULL	7	100.00	Using index
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	7	100.00	Using where
 Warnings:
-Note	1003	select `test`.`t1`.`a` AS `a` from `test`.`t1` group by `test`.`t1`.`a` having <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` = `materialized subselect`.`c`)))))
+Note	1003	select `test`.`t1`.`a` AS `a` from `test`.`t1` group by `test`.`t1`.`a` having <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 group by a having a in (select c from t2 where d >= 20);
 a
 2
@@ -1083,7 +1133,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	t1	index	NULL	it1a	4	NULL	7	100.00	Using index
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	7	100.00	Using where
 Warnings:
-Note	1003	select `test`.`t1`.`a` AS `a` from `test`.`t1` group by `test`.`t1`.`a` having <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` = `materialized subselect`.`c`)))))
+Note	1003	select `test`.`t1`.`a` AS `a` from `test`.`t1` group by `test`.`t1`.`a` having <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 group by a having a in (select c from t2 where d >= 20);
 a
 2
@@ -1138,10 +1188,12 @@ 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	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Select tables optimized away
-2	SUBQUERY	t2	system	NULL	NULL	NULL	NULL	0	const row not found
+1	PRIMARY	t1	system	NULL	NULL	NULL	NULL	1	
+1	PRIMARY	SUBQUERY#2	const	distinct_key	distinct_key	5	const	1	
+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 @@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
@@ -1152,17 +1204,27 @@ 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	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Select tables optimized away
-2	SUBQUERY	t2	system	NULL	NULL	NULL	NULL	0	const row not found
+1	PRIMARY	t1	system	NULL	NULL	NULL	NULL	1	
+1	PRIMARY	SUBQUERY#2	const	distinct_key	distinct_key	5	const	1	
+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);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	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);
 min(a1)
 NULL
+# 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;
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	NULL	NULL	NULL	NULL	NULL	NULL	NULL	Select tables optimized away
+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)
 drop table t1,t2;
 create table t1 (a char(2), b varchar(10));
 insert into t1 values ('a',  'aaa');
@@ -1170,7 +1232,8 @@ 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	Using where
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	2	
+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
@@ -1190,7 +1253,7 @@ 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);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	subselect2	ALL	unique_key	NULL	NULL	NULL	2	
+1	PRIMARY	SUBQUERY#2	ALL	unique_key	NULL	NULL	NULL	2	
 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	Using where; Using join buffer
 2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	2	
 SELECT COUNT(*) FROM t1 WHERE (f1,f2) IN (SELECT f1,f2 FROM t2);
@@ -1212,7 +1275,7 @@ 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
 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	2	
-1	PRIMARY	subselect2	eq_ref	unique_key	unique_key	5	func	1	
+1	PRIMARY	SUBQUERY#2	eq_ref	unique_key	unique_key	5	func	1	
 2	SUBQUERY	t2	range	PRIMARY	PRIMARY	4	NULL	2	Using index condition; Using MRR
 SELECT pk FROM t1 WHERE (a) IN (SELECT a FROM t2 WHERE pk > 0);
 pk
--- a/mysql-test/r/subselect_no_semijoin.result
+++ b/mysql-test/r/subselect_no_semijoin.result
@@ -1299,31 +1299,34 @@ 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	NULL	PRIMARY	4	NULL	4	100.00	Using where; Using index
+1	PRIMARY	SUBQUERY#2	ALL	distinct_key	NULL	NULL	NULL	4	100.00	
+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 `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` = `materialized subselect`.`a`)))))
+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`)
 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	NULL	PRIMARY	4	NULL	4	100.00	Using where; Using index
+1	PRIMARY	SUBQUERY#2	ALL	distinct_key	NULL	NULL	NULL	4	100.00	
+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 `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` = `materialized subselect`.`a`)))))
+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`)
 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	NULL	PRIMARY	4	NULL	4	100.00	Using where; Using index
+1	PRIMARY	t2	index	PRIMARY	PRIMARY	4	NULL	4	100.00	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 `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` = `materialized subselect`.`a`)))))
+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`)
 drop table t1, t2, t3;
 create table t1 (a int, b int, index a (a,b));
 create table t2 (a int, index a (a));
@@ -1342,31 +1345,34 @@ 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	NULL	a	5	NULL	4	100.00	Using where; Using index
+1	PRIMARY	t2	index	a	a	5	NULL	4	100.00	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 `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` = `materialized subselect`.`a`)))))
+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`)
 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	NULL	a	5	NULL	4	100.00	Using where; Using index
+1	PRIMARY	t2	index	a	a	5	NULL	4	100.00	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 `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` = `materialized subselect`.`a`)))))
+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`)
 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	NULL	a	5	NULL	4	100.00	Using where; Using index
+1	PRIMARY	t2	index	a	a	5	NULL	4	100.00	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 `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` = `materialized subselect`.`a`)))))
+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`)
 insert into t1 values (3,31);
 select * from t2 where t2.a in (select a from t1 where t1.b <> 30);
 a
@@ -1379,10 +1385,11 @@ 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	NULL	a	5	NULL	4	100.00	Using where; Using index
+1	PRIMARY	t2	index	a	a	5	NULL	4	100.00	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 `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` = `materialized subselect`.`a`)))))
+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`)
 drop table t0, t1, t2, t3;
 create table t1 (a int, b int);
 create table t2 (a int, b int);
@@ -2833,10 +2840,11 @@ 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	Using where
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	8	100.00	
+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 `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` = `materialized subselect`.`one`) and (`test`.`t1`.`two` = `materialized subselect`.`two`)))))
+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`))
 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	
@@ -3421,7 +3429,8 @@ 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	Using where
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	9	
+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);
@@ -3432,7 +3441,8 @@ 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	Using where
+1	PRIMARY	t1	ALL	a	NULL	NULL	NULL	9	
+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);
@@ -4206,7 +4216,8 @@ 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	NULL	NULL	NULL	NULL	2	Using where
+1	PRIMARY	t1	ALL	I2	NULL	NULL	NULL	2	
+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
@@ -4216,14 +4227,16 @@ 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	NULL	NULL	NULL	NULL	2	Using where
+1	PRIMARY	t2	ALL	I2	NULL	NULL	NULL	2	
+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	NULL	NULL	NULL	NULL	2	Using where
+1	PRIMARY	t1	ALL	I2	NULL	NULL	NULL	2	
+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
@@ -4326,16 +4339,18 @@ 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	Using where
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	2	100.00	
+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 `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 = `materialized subselect`.`1`)))))
+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)
 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	Using where
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	2	100.00	
+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 `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 = `materialized subselect`.`1`)))))
+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)
 DROP TABLE t1;
 #
 # Bug#45061: Incorrectly market field caused wrong result.
--- a/mysql-test/r/subselect_sj.result
+++ b/mysql-test/r/subselect_sj.result
@@ -848,7 +848,7 @@ INSERT INTO t2 VALUES (1,'i','iiii','iiii','iiii','iiii','ffff','ffff','ffff','f
 EXPLAIN EXTENDED SELECT pk FROM t1 WHERE (a, b) IN (SELECT a, b FROM t2 WHERE pk > 0);
 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	subselect2	eq_ref	unique_key	unique_key	13	func	1	1.00	
+1	PRIMARY	SUBQUERY#2	eq_ref	unique_key	unique_key	13	func	1	1.00	
 2	SUBQUERY	t2	range	PRIMARY	PRIMARY	4	NULL	2	100.00	Using index condition; Using MRR
 Warnings:
 Note	1003	select `test`.`t1`.`pk` AS `pk` from `test`.`t1` semi join (`test`.`t2`) where ((`test`.`t2`.`pk` > 0))
@@ -1017,7 +1017,7 @@ FROM t1
 WHERE `varchar_nokey`  < 'n' XOR `pk`  )   ;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	18	100.00	
-1	PRIMARY	subselect2	eq_ref	unique_key	unique_key	8	func	1	1.00	
+1	PRIMARY	SUBQUERY#2	eq_ref	unique_key	unique_key	8	func	1	1.00	
 2	SUBQUERY	t1	ALL	varchar_key	NULL	NULL	NULL	15	100.00	Using where
 Warnings:
 Note	1003	select `test`.`t2`.`varchar_nokey` AS `varchar_nokey` from `test`.`t2` semi join (`test`.`t1`) where ((`test`.`t1`.`varchar_nokey` = `test`.`t1`.`varchar_key`) and ((`test`.`t1`.`varchar_nokey` < 'n') xor `test`.`t1`.`pk`))
--- a/mysql-test/r/subselect_sj2.result
+++ b/mysql-test/r/subselect_sj2.result
@@ -32,7 +32,7 @@ a	b
 9	5
 explain select * from t2 where b in (select a from t1);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	subselect2	ALL	unique_key	NULL	NULL	NULL	3	
+1	PRIMARY	SUBQUERY#2	ALL	unique_key	NULL	NULL	NULL	3	
 1	PRIMARY	t2	ref	b	b	5	test.t1.a	2	
 2	SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	3	
 select * from t2 where b in (select a from t1);
@@ -74,7 +74,7 @@ A.a + 10*B.a, A.a + 10*B.a, A.a + 10*B.a, A.a + 10*B.a
 from t0 A, t0 B where B.a <5;
 explain select * from t3 where b in (select a from t0);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	subselect2	ALL	unique_key	NULL	NULL	NULL	10	
+1	PRIMARY	SUBQUERY#2	ALL	unique_key	NULL	NULL	NULL	10	
 1	PRIMARY	t3	ref	b	b	5	test.t0.a	1	
 2	SUBQUERY	t0	ALL	NULL	NULL	NULL	NULL	10	
 set @save_ecp= @@engine_condition_pushdown;
@@ -101,7 +101,7 @@ set max_heap_table_size= @save_max_heap_table_size;
 explain select * from t1 where a in (select b from t2);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	
-1	PRIMARY	subselect2	eq_ref	unique_key	unique_key	5	func	1	
+1	PRIMARY	SUBQUERY#2	eq_ref	unique_key	unique_key	5	func	1	
 2	SUBQUERY	t2	index	b	b	5	NULL	10	Using index
 select * from t1;
 a	b
@@ -129,7 +129,7 @@ explain select
 a, mid(filler1, 1,10), length(filler1)=length(filler2) as Z 
 from t1 ot where a in (select a from t2 it);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	subselect2	ALL	unique_key	NULL	NULL	NULL	22	
+1	PRIMARY	SUBQUERY#2	ALL	unique_key	NULL	NULL	NULL	22	
 1	PRIMARY	ot	ALL	NULL	NULL	NULL	NULL	32	Using where; Using join buffer
 2	SUBQUERY	it	ALL	NULL	NULL	NULL	NULL	22	
 select 
@@ -163,7 +163,7 @@ a, mid(filler1, 1,10), length(filler1)=length(filler2)
 from t2 ot where a in (select a from t1 it);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	ot	ALL	NULL	NULL	NULL	NULL	22	
-1	PRIMARY	subselect2	eq_ref	unique_key	unique_key	5	func	1	
+1	PRIMARY	SUBQUERY#2	eq_ref	unique_key	unique_key	5	func	1	
 2	SUBQUERY	it	ALL	NULL	NULL	NULL	NULL	32	
 select 
 a, mid(filler1, 1,10), length(filler1)=length(filler2) 
@@ -197,7 +197,7 @@ explain select
 a, mid(filler1, 1,10), length(filler1)=length(filler2) as Z 
 from t1 ot where a in (select a from t2 it);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	subselect2	ALL	unique_key	NULL	NULL	NULL	22	
+1	PRIMARY	SUBQUERY#2	ALL	unique_key	NULL	NULL	NULL	22	
 1	PRIMARY	ot	ALL	NULL	NULL	NULL	NULL	52	Using where; Using join buffer
 2	SUBQUERY	it	ALL	NULL	NULL	NULL	NULL	22	
 select 
@@ -231,7 +231,7 @@ a, mid(filler1, 1,10), length(filler1)=length(filler2)
 from t2 ot where a in (select a from t1 it);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	ot	ALL	NULL	NULL	NULL	NULL	22	
-1	PRIMARY	subselect2	eq_ref	unique_key	unique_key	5	func	1	
+1	PRIMARY	SUBQUERY#2	eq_ref	unique_key	unique_key	5	func	1	
 2	SUBQUERY	it	ALL	NULL	NULL	NULL	NULL	52	
 select 
 a, mid(filler1, 1,10), length(filler1)=length(filler2) 
@@ -348,7 +348,7 @@ WHERE t1.Code IN (
 SELECT t2.CountryCode FROM t2 WHERE Population > 5000000);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t1	ALL	PRIMARY	NULL	NULL	NULL	31	
-1	PRIMARY	subselect2	eq_ref	unique_key	unique_key	3	func	1	
+1	PRIMARY	SUBQUERY#2	eq_ref	unique_key	unique_key	3	func	1	
 2	SUBQUERY	t2	ALL	CountryCode	NULL	NULL	NULL	545	Using where
 SELECT Name FROM t1 
 WHERE t1.Code IN (
@@ -359,6 +359,10 @@ Canada
 China
 Czech Republic
 drop table t1, t2;
+drop procedure if exists p1;
+drop procedure if exists p2;
+drop procedure if exists p3;
+drop procedure if exists p4;
 CREATE TABLE t1(a INT);
 CREATE TABLE t2(c INT);
 CREATE PROCEDURE p1(v1 int)
@@ -692,7 +696,7 @@ The following must use loose index scan over t3, key a:
 explain select count(a) from t2 where a in ( SELECT  a FROM t3);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t2	index	a	a	5	NULL	1000	Using index
-1	PRIMARY	subselect2	eq_ref	unique_key	unique_key	5	func	1	
+1	PRIMARY	SUBQUERY#2	eq_ref	unique_key	unique_key	5	func	1	
 2	SUBQUERY	t3	index	a	a	5	NULL	30000	Using index
 select count(a) from t2 where a in ( SELECT  a FROM t3);
 count(a)
--- a/mysql-test/r/subselect_sj2_jcl6.result
+++ b/mysql-test/r/subselect_sj2_jcl6.result
@@ -36,7 +36,7 @@ a	b
 9	5
 explain select * from t2 where b in (select a from t1);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	subselect2	ALL	unique_key	NULL	NULL	NULL	3	
+1	PRIMARY	SUBQUERY#2	ALL	unique_key	NULL	NULL	NULL	3	
 1	PRIMARY	t2	ref	b	b	5	test.t1.a	2	Using join buffer
 2	SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	3	
 select * from t2 where b in (select a from t1);
@@ -78,7 +78,7 @@ A.a + 10*B.a, A.a + 10*B.a, A.a + 10*B.a, A.a + 10*B.a
 from t0 A, t0 B where B.a <5;
 explain select * from t3 where b in (select a from t0);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	subselect2	ALL	unique_key	NULL	NULL	NULL	10	
+1	PRIMARY	SUBQUERY#2	ALL	unique_key	NULL	NULL	NULL	10	
 1	PRIMARY	t3	ref	b	b	5	test.t0.a	1	Using join buffer
 2	SUBQUERY	t0	ALL	NULL	NULL	NULL	NULL	10	
 set @save_ecp= @@engine_condition_pushdown;
@@ -105,7 +105,7 @@ set max_heap_table_size= @save_max_heap_table_size;
 explain select * from t1 where a in (select b from t2);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	3	
-1	PRIMARY	subselect2	eq_ref	unique_key	unique_key	5	func	1	
+1	PRIMARY	SUBQUERY#2	eq_ref	unique_key	unique_key	5	func	1	
 2	SUBQUERY	t2	index	b	b	5	NULL	10	Using index
 select * from t1;
 a	b
@@ -133,7 +133,7 @@ explain select
 a, mid(filler1, 1,10), length(filler1)=length(filler2) as Z 
 from t1 ot where a in (select a from t2 it);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	subselect2	ALL	unique_key	NULL	NULL	NULL	22	
+1	PRIMARY	SUBQUERY#2	ALL	unique_key	NULL	NULL	NULL	22	
 1	PRIMARY	ot	ALL	NULL	NULL	NULL	NULL	32	Using where; Using join buffer
 2	SUBQUERY	it	ALL	NULL	NULL	NULL	NULL	22	
 select 
@@ -167,7 +167,7 @@ a, mid(filler1, 1,10), length(filler1)=length(filler2)
 from t2 ot where a in (select a from t1 it);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	ot	ALL	NULL	NULL	NULL	NULL	22	
-1	PRIMARY	subselect2	eq_ref	unique_key	unique_key	5	func	1	
+1	PRIMARY	SUBQUERY#2	eq_ref	unique_key	unique_key	5	func	1	
 2	SUBQUERY	it	ALL	NULL	NULL	NULL	NULL	32	
 select 
 a, mid(filler1, 1,10), length(filler1)=length(filler2) 
@@ -201,7 +201,7 @@ explain select
 a, mid(filler1, 1,10), length(filler1)=length(filler2) as Z 
 from t1 ot where a in (select a from t2 it);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	subselect2	ALL	unique_key	NULL	NULL	NULL	22	
+1	PRIMARY	SUBQUERY#2	ALL	unique_key	NULL	NULL	NULL	22	
 1	PRIMARY	ot	ALL	NULL	NULL	NULL	NULL	52	Using where; Using join buffer
 2	SUBQUERY	it	ALL	NULL	NULL	NULL	NULL	22	
 select 
@@ -235,7 +235,7 @@ a, mid(filler1, 1,10), length(filler1)=length(filler2)
 from t2 ot where a in (select a from t1 it);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	ot	ALL	NULL	NULL	NULL	NULL	22	
-1	PRIMARY	subselect2	eq_ref	unique_key	unique_key	5	func	1	
+1	PRIMARY	SUBQUERY#2	eq_ref	unique_key	unique_key	5	func	1	
 2	SUBQUERY	it	ALL	NULL	NULL	NULL	NULL	52	
 select 
 a, mid(filler1, 1,10), length(filler1)=length(filler2) 
@@ -352,7 +352,7 @@ WHERE t1.Code IN (
 SELECT t2.CountryCode FROM t2 WHERE Population > 5000000);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t1	ALL	PRIMARY	NULL	NULL	NULL	31	
-1	PRIMARY	subselect2	eq_ref	unique_key	unique_key	3	func	1	
+1	PRIMARY	SUBQUERY#2	eq_ref	unique_key	unique_key	3	func	1	
 2	SUBQUERY	t2	ALL	CountryCode	NULL	NULL	NULL	545	Using where
 SELECT Name FROM t1 
 WHERE t1.Code IN (
@@ -363,6 +363,10 @@ Canada
 China
 Czech Republic
 drop table t1, t2;
+drop procedure if exists p1;
+drop procedure if exists p2;
+drop procedure if exists p3;
+drop procedure if exists p4;
 CREATE TABLE t1(a INT);
 CREATE TABLE t2(c INT);
 CREATE PROCEDURE p1(v1 int)
@@ -698,7 +702,7 @@ The following must use loose index scan over t3, key a:
 explain select count(a) from t2 where a in ( SELECT  a FROM t3);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t2	index	a	a	5	NULL	1000	Using index
-1	PRIMARY	subselect2	eq_ref	unique_key	unique_key	5	func	1	
+1	PRIMARY	SUBQUERY#2	eq_ref	unique_key	unique_key	5	func	1	
 2	SUBQUERY	t3	index	a	a	5	NULL	30000	Using index
 select count(a) from t2 where a in ( SELECT  a FROM t3);
 count(a)
--- a/mysql-test/r/subselect_sj_jcl6.result
+++ b/mysql-test/r/subselect_sj_jcl6.result
@@ -852,7 +852,7 @@ INSERT INTO t2 VALUES (1,'i','iiii','iiii','iiii','iiii','ffff','ffff','ffff','f
 EXPLAIN EXTENDED SELECT pk FROM t1 WHERE (a, b) IN (SELECT a, b FROM t2 WHERE pk > 0);
 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	subselect2	eq_ref	unique_key	unique_key	13	func	1	1.00	
+1	PRIMARY	SUBQUERY#2	eq_ref	unique_key	unique_key	13	func	1	1.00	
 2	SUBQUERY	t2	range	PRIMARY	PRIMARY	4	NULL	2	100.00	Using index condition; Using MRR
 Warnings:
 Note	1003	select `test`.`t1`.`pk` AS `pk` from `test`.`t1` semi join (`test`.`t2`) where ((`test`.`t2`.`pk` > 0))
@@ -1021,7 +1021,7 @@ FROM t1
 WHERE `varchar_nokey`  < 'n' XOR `pk`  )   ;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	18	100.00	
-1	PRIMARY	subselect2	eq_ref	unique_key	unique_key	8	func	1	1.00	
+1	PRIMARY	SUBQUERY#2	eq_ref	unique_key	unique_key	8	func	1	1.00	
 2	SUBQUERY	t1	ALL	varchar_key	NULL	NULL	NULL	15	100.00	Using where
 Warnings:
 Note	1003	select `test`.`t2`.`varchar_nokey` AS `varchar_nokey` from `test`.`t2` semi join (`test`.`t1`) where ((`test`.`t1`.`varchar_nokey` = `test`.`t1`.`varchar_key`) and ((`test`.`t1`.`varchar_nokey` < 'n') xor `test`.`t1`.`pk`))
--- a/mysql-test/r/view.result
+++ b/mysql-test/r/view.result
@@ -303,7 +303,7 @@ a+1
 explain select * from v1;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	<derived2>	ALL	NULL	NULL	NULL	NULL	2	
-2	DERIVED	t1	ALL	NULL	NULL	NULL	NULL	4	Using filesort
+2	DERIVED	t1	ALL	NULL	NULL	NULL	NULL	2	Using filesort
 drop view v1;
 drop table t1;
 create table t1 (a int);
--- a/mysql-test/suite/parts/r/partition_alter3_innodb.result
+++ b/mysql-test/suite/parts/r/partition_alter3_innodb.result
@@ -141,7 +141,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) FROM t1 WHERE f_date = '1000-02-10';
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	part1	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	part1	ALL	NULL	NULL	NULL	NULL	7	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -165,7 +165,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) FROM t1 WHERE f_date = '1000-02-10';
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	5	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -190,7 +190,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) FROM t1 WHERE f_date = '1000-02-10';
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	3	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -226,7 +226,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) FROM t1 WHERE f_date = '1000-02-10';
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p6	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	p6	ALL	NULL	NULL	NULL	NULL	3	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -248,7 +248,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) FROM t1 WHERE f_date = '1000-02-10';
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p4	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	p4	ALL	NULL	NULL	NULL	NULL	4	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -269,7 +269,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) FROM t1 WHERE f_date = '1000-02-10';
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	4	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -289,7 +289,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) FROM t1 WHERE f_date = '1000-02-10';
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	5	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -308,7 +308,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) FROM t1 WHERE f_date = '1000-02-10';
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	part1	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	part1	ALL	NULL	NULL	NULL	NULL	7	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -326,7 +326,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) FROM t1 WHERE f_date = '1000-02-10';
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	10	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -452,7 +452,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) <> 1 FROM t1 WHERE f_int1 = 3;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	part7	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	part7	ALL	NULL	NULL	NULL	NULL	7	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -476,7 +476,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) <> 1 FROM t1 WHERE f_int1 = 3;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	part7	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	part7	ALL	NULL	NULL	NULL	NULL	5	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -504,7 +504,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) <> 1 FROM t1 WHERE f_int1 = 3;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p6	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	p6	ALL	NULL	NULL	NULL	NULL	3	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -538,7 +538,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) <> 1 FROM t1 WHERE f_int1 = 3;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	4	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -563,7 +563,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) <> 1 FROM t1 WHERE f_int1 = 3;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	part7	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	part7	ALL	NULL	NULL	NULL	NULL	3	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -587,7 +587,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) <> 1 FROM t1 WHERE f_int1 = 3;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p4	ALL	NULL	NULL	NULL	NULL	23	Using where
+1	SIMPLE	t1	p4	ALL	NULL	NULL	NULL	NULL	10	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -610,7 +610,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) <> 1 FROM t1 WHERE f_int1 = 3;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	part7	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	part7	ALL	NULL	NULL	NULL	NULL	5	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -632,7 +632,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) <> 1 FROM t1 WHERE f_int1 = 3;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	part7	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	part7	ALL	NULL	NULL	NULL	NULL	7	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -653,7 +653,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) <> 1 FROM t1 WHERE f_int1 = 3;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	10	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
--- a/mysql-test/suite/parts/r/partition_alter3_myisam.result
+++ b/mysql-test/suite/parts/r/partition_alter3_myisam.result
@@ -155,7 +155,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) FROM t1 WHERE f_date = '1000-02-10';
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	part1	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	part1	ALL	NULL	NULL	NULL	NULL	7	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -187,7 +187,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) FROM t1 WHERE f_date = '1000-02-10';
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	5	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -228,7 +228,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) FROM t1 WHERE f_date = '1000-02-10';
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	3	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -278,7 +278,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) FROM t1 WHERE f_date = '1000-02-10';
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p6	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	p6	ALL	NULL	NULL	NULL	NULL	3	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -312,7 +312,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) FROM t1 WHERE f_date = '1000-02-10';
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p4	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	p4	ALL	NULL	NULL	NULL	NULL	4	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -343,7 +343,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) FROM t1 WHERE f_date = '1000-02-10';
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	4	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -371,7 +371,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) FROM t1 WHERE f_date = '1000-02-10';
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	5	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -396,7 +396,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) FROM t1 WHERE f_date = '1000-02-10';
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	part1	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	part1	ALL	NULL	NULL	NULL	NULL	7	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -418,7 +418,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) FROM t1 WHERE f_date = '1000-02-10';
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	10	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -552,7 +552,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) <> 1 FROM t1 WHERE f_int1 = 3;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	part7	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	part7	ALL	NULL	NULL	NULL	NULL	7	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -584,7 +584,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) <> 1 FROM t1 WHERE f_int1 = 3;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	part7	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	part7	ALL	NULL	NULL	NULL	NULL	5	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -628,7 +628,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) <> 1 FROM t1 WHERE f_int1 = 3;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p6	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	p6	ALL	NULL	NULL	NULL	NULL	3	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -676,7 +676,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) <> 1 FROM t1 WHERE f_int1 = 3;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	4	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -713,7 +713,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) <> 1 FROM t1 WHERE f_int1 = 3;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	part7	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	part7	ALL	NULL	NULL	NULL	NULL	3	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -747,7 +747,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) <> 1 FROM t1 WHERE f_int1 = 3;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p4	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	p4	ALL	NULL	NULL	NULL	NULL	10	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -778,7 +778,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) <> 1 FROM t1 WHERE f_int1 = 3;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	part7	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	part7	ALL	NULL	NULL	NULL	NULL	5	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -806,7 +806,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) <> 1 FROM t1 WHERE f_int1 = 3;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	part7	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	part7	ALL	NULL	NULL	NULL	NULL	7	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
@@ -831,7 +831,7 @@ t1.frm
 t1.par
 EXPLAIN PARTITIONS SELECT COUNT(*) <> 1 FROM t1 WHERE f_int1 = 3;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	20	Using where
+1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	10	Using where
 # check read single success: 1
 # check read all success: 1
 # check read row by row success: 1
--- a/mysql-test/suite/pbxt/r/group_min_max.result
+++ b/mysql-test/suite/pbxt/r/group_min_max.result
@@ -2256,7 +2256,8 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 EXPLAIN SELECT 1 FROM t1 AS t1_outer WHERE 
 a IN (SELECT max(b) FROM t1 GROUP BY a HAVING a < 2);
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	PRIMARY	t1_outer	index	NULL	a	10	NULL	15	Using where; Using index
+1	PRIMARY	SUBQUERY#2	ALL	distinct_key	NULL	NULL	NULL	15	
+1	PRIMARY	t1_outer	ref	a	a	5	SUBQUERY#2.max(b)	1	Using index
 2	SUBQUERY	t1	index	NULL	a	10	NULL	15	Using index
 EXPLAIN SELECT 1 FROM t1 AS t1_outer GROUP BY a HAVING 
 a > (SELECT max(b) FROM t1 GROUP BY a HAVING a < 2);
--- a/mysql-test/suite/pbxt/r/metadata.result
+++ b/mysql-test/suite/pbxt/r/metadata.result
@@ -55,7 +55,7 @@ id	data	data
 2	female	no
 select t1.id from t1 union select t2.id from t2;
 Catalog	Database	Table	Table_alias	Column	Column_alias	Type	Length	Max length	Is_null	Flags	Decimals	Charsetnr
-def				id	id	1	4	1	Y	32768	0	63
+def				id	id	1	4	1	Y	49152	0	63
 id
 1
 2
@@ -66,7 +66,7 @@ insert into t1 values (2,'two');
 set @arg00=1 ;
 select @arg00 FROM t1 where a=1 union distinct select 1 FROM t1 where a=1;
 Catalog	Database	Table	Table_alias	Column	Column_alias	Type	Length	Max length	Is_null	Flags	Decimals	Charsetnr
-def				@arg00	@arg00	8	20	1	Y	32768	0	63
+def				@arg00	@arg00	8	20	1	Y	49152	0	63
@arg00
 1
 select * from (select @arg00) aaa;
@@ -76,7 +76,7 @@ def			aaa	@arg00	@arg00	8	20	1	Y	32768	0	63
 1
 select 1 union select 1;
 Catalog	Database	Table	Table_alias	Column	Column_alias	Type	Length	Max length	Is_null	Flags	Decimals	Charsetnr
-def				1	1	8	20	1	N	32769	0	63
+def				1	1	8	20	1	N	49153	0	63
 1
 1
 select * from (select 1 union select 1) aaa;
--- a/mysql-test/suite/pbxt/r/partition_hash.result
+++ b/mysql-test/suite/pbxt/r/partition_hash.result
@@ -57,25 +57,25 @@ id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	p0,p1,p2,p3	ALL	NULL	NULL	NULL	NULL	9	Using where
 explain partitions select * from t1 where a is null or (a >= 5 and a <= 7);
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0,p2,p3	ALL	NULL	NULL	NULL	NULL	9	Using where
+1	SIMPLE	t1	p0,p2,p3	ALL	NULL	NULL	NULL	NULL	7	Using where
 explain partitions select * from t1 where a is null;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	9	Using where
+1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	3	Using where
 explain partitions select * from t1 where a is not null;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	p0,p1,p2,p3	ALL	NULL	NULL	NULL	NULL	9	Using where
 explain partitions select * from t1 where a >= 1 and a < 3;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0,p1	ALL	NULL	NULL	NULL	NULL	9	Using where
+1	SIMPLE	t1	p0,p1	ALL	NULL	NULL	NULL	NULL	5	Using where
 explain partitions select * from t1 where a >= 3 and a <= 5;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p1,p2	ALL	NULL	NULL	NULL	NULL	9	Using where
+1	SIMPLE	t1	p1,p2	ALL	NULL	NULL	NULL	NULL	4	Using where
 explain partitions select * from t1 where a > 2 and a < 4;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p1	ALL	NULL	NULL	NULL	NULL	9	Using where
+1	SIMPLE	t1	p1	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where a > 3 and a <= 6;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p2,p3	ALL	NULL	NULL	NULL	NULL	9	Using where
+1	SIMPLE	t1	p2,p3	ALL	NULL	NULL	NULL	NULL	4	Using where
 explain partitions select * from t1 where a > 5;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	p0,p1,p2,p3	ALL	NULL	NULL	NULL	NULL	9	Using where
--- a/mysql-test/suite/pbxt/r/partition_pruning.result
+++ b/mysql-test/suite/pbxt/r/partition_pruning.result
@@ -14,7 +14,7 @@ id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	p1	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where a=2;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	3	Using where
+1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where a=1 or a=2;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	p0,p1	ALL	NULL	NULL	NULL	NULL	3	Using where
@@ -31,7 +31,7 @@ id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t2	p0,p1	ALL	NULL	NULL	NULL	NULL	3	Using where
 explain partitions select * from t2 where a=1 and b=1;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t2	p0	ALL	NULL	NULL	NULL	NULL	3	Using where
+1	SIMPLE	t2	p0	ALL	NULL	NULL	NULL	NULL	2	Using where
 create table t3 (
 a int
 )
@@ -42,16 +42,16 @@ partition p1 values less than (20)
 insert into t3 values (5),(15);
 explain partitions select * from t3 where a=11;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t3	p1	ALL	NULL	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t3	p1	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t3 where a=10;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t3	p1	ALL	NULL	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t3	p1	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t3 where a=20;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t3		ALL	NULL	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t3		ALL	NULL	NULL	NULL	NULL	0	Using where
 explain partitions select * from t3 where a=30;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t3		ALL	NULL	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t3		ALL	NULL	NULL	NULL	NULL	0	Using where
 create table t4 (a int not null, b int not null) partition by LIST (a+b) (
 partition p0 values in (12),
 partition p1 values in (14)
@@ -59,11 +59,11 @@ partition p1 values in (14)
 insert into t4 values (10,2), (10,4);
 explain partitions select * from t4 where (a=10 and b=1) or (a=10 and b=2);
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t4	p0	ALL	NULL	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t4	p0	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t4 
 where (a=10 and b=1) or (a=10 and b=2) or (a=10 and b = 3);
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t4	p0	ALL	NULL	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t4	p0	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t4 where (a=10 and b=2) or (a=10 and b=3)
 or (a=10 and b = 4);
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
@@ -89,25 +89,25 @@ id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 explain partitions select * from t5
 where (a=10 and b=1) or (a=10 and b=2) or (a=10 and b = 3);
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t5	p0_p0sp0,p0_p0sp1	ALL	NULL	NULL	NULL	NULL	4	Using where
+1	SIMPLE	t5	p0_p0sp0,p0_p0sp1	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t5 where (a=10 and b=2) or (a=10 and b=3)
 or (a=10 and b = 4);
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t5	p0_p0sp0,p0_p0sp1,p1_p1sp0,p1_p1sp1	ALL	NULL	NULL	NULL	NULL	4	Using where
 explain partitions select * from t5 where (c=1 and d=1);
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t5	p0_p0sp0,p1_p1sp0	ALL	NULL	NULL	NULL	NULL	4	Using where
+1	SIMPLE	t5	p0_p0sp0,p1_p1sp0	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t5 where (c=2 and d=1);
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t5	p0_p0sp1,p1_p1sp1	ALL	NULL	NULL	NULL	NULL	4	Using where
+1	SIMPLE	t5	p0_p0sp1,p1_p1sp1	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t5 where (a=10 and b=2 and c=1 and d=1) or 
 (c=2 and d=1);
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t5	p0_p0sp0,p0_p0sp1,p1_p1sp1	ALL	NULL	NULL	NULL	NULL	4	Using where
+1	SIMPLE	t5	p0_p0sp0,p0_p0sp1,p1_p1sp1	ALL	NULL	NULL	NULL	NULL	3	Using where
 explain partitions select * from t5 where (a=10 and b=2 and c=1 and d=1) or 
 (b=2 and c=2 and d=1);
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t5	p0_p0sp0,p0_p0sp1,p1_p1sp1	ALL	NULL	NULL	NULL	NULL	4	Using where
+1	SIMPLE	t5	p0_p0sp0,p0_p0sp1,p1_p1sp1	ALL	NULL	NULL	NULL	NULL	3	Using where
 create table t6 (a int not null) partition by LIST(a) (
 partition p1 values in (1),
 partition p3 values in (3),
@@ -121,34 +121,34 @@ id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t6		ALL	NULL	NULL	NULL	NULL	0	Using where
 explain partitions select * from t6 where a <= 1;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t6	p1	ALL	NULL	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t6	p1	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t6 where a >  9;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t6		ALL	NULL	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t6		ALL	NULL	NULL	NULL	NULL	0	Using where
 explain partitions select * from t6 where a >= 9;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t6	p9	ALL	NULL	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t6	p9	ALL	NULL	NULL	NULL	NULL	0	Using where
 explain partitions select * from t6 where a > 0 and a < 5;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t6	p1,p3	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t6 where a > 5 and a < 12;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t6	p7,p9	ALL	NULL	NULL	NULL	NULL	2	Using where
+1	SIMPLE	t6	p7,p9	ALL	NULL	NULL	NULL	NULL	0	Using where
 explain partitions select * from t6 where a > 3 and a < 8 ;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t6	p5,p7	ALL	NULL	NULL	NULL	NULL	3	Using where
+1	SIMPLE	t6	p5,p7	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t6 where a >= 0 and a <= 5;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t6	p1,p3,p5	ALL	NULL	NULL	NULL	NULL	3	Using where
 explain partitions select * from t6 where a >= 5 and a <= 12;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t6	p5,p7,p9	ALL	NULL	NULL	NULL	NULL	3	Using where
+1	SIMPLE	t6	p5,p7,p9	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t6 where a >= 3 and a <= 8;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t6	p3,p5,p7	ALL	NULL	NULL	NULL	NULL	3	Using where
+1	SIMPLE	t6	p3,p5,p7	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t6 where a > 3 and a < 5;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t6		ALL	NULL	NULL	NULL	NULL	3	Using where
+1	SIMPLE	t6		ALL	NULL	NULL	NULL	NULL	0	Using where
 drop table t6;
 create table t6 (a int unsigned not null) partition by LIST(a) (
 partition p1 values in (1),
@@ -163,34 +163,34 @@ id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t6		ALL	NULL	NULL	NULL	NULL	0	Using where
 explain partitions select * from t6 where a <= 1;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t6	p1	ALL	NULL	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t6	p1	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t6 where a >  9;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t6		ALL	NULL	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t6		ALL	NULL	NULL	NULL	NULL	0	Using where
 explain partitions select * from t6 where a >= 9;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t6	p9	ALL	NULL	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t6	p9	ALL	NULL	NULL	NULL	NULL	0	Using where
 explain partitions select * from t6 where a > 0 and a < 5;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t6	p1,p3	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t6 where a > 5 and a < 12;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t6	p7,p9	ALL	NULL	NULL	NULL	NULL	2	Using where
+1	SIMPLE	t6	p7,p9	ALL	NULL	NULL	NULL	NULL	0	Using where
 explain partitions select * from t6 where a > 3 and a < 8 ;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t6	p5,p7	ALL	NULL	NULL	NULL	NULL	3	Using where
+1	SIMPLE	t6	p5,p7	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t6 where a >= 0 and a <= 5;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t6	p1,p3,p5	ALL	NULL	NULL	NULL	NULL	3	Using where
 explain partitions select * from t6 where a >= 5 and a <= 12;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t6	p5,p7,p9	ALL	NULL	NULL	NULL	NULL	3	Using where
+1	SIMPLE	t6	p5,p7,p9	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t6 where a >= 3 and a <= 8;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t6	p3,p5,p7	ALL	NULL	NULL	NULL	NULL	3	Using where
+1	SIMPLE	t6	p3,p5,p7	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t6 where a > 3 and a < 5;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t6		ALL	NULL	NULL	NULL	NULL	3	Using where
+1	SIMPLE	t6		ALL	NULL	NULL	NULL	NULL	0	Using where
 create table t7 (a int not null) partition by RANGE(a) (
 partition p10 values less than (10),
 partition p30 values less than (30),
@@ -207,25 +207,25 @@ id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t7	p10	ALL	NULL	NULL	NULL	NULL	0	Using where
 explain partitions select * from t7 where a <= 10;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t7	p10,p30	ALL	NULL	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t7	p10,p30	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t7 where a = 10;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t7	p30	ALL	NULL	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t7	p30	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t7 where a < 90;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t7	p10,p30,p50,p70,p90	ALL	NULL	NULL	NULL	NULL	3	Using where
 explain partitions select * from t7 where a = 90;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t7		ALL	NULL	NULL	NULL	NULL	3	Using where
+1	SIMPLE	t7		ALL	NULL	NULL	NULL	NULL	0	Using where
 explain partitions select * from t7 where a > 90;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t7		ALL	NULL	NULL	NULL	NULL	3	Using where
+1	SIMPLE	t7		ALL	NULL	NULL	NULL	NULL	0	Using where
 explain partitions select * from t7 where a >= 90;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t7		ALL	NULL	NULL	NULL	NULL	3	Using where
+1	SIMPLE	t7		ALL	NULL	NULL	NULL	NULL	0	Using where
 explain partitions select * from t7 where a > 11 and a < 29;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t7	p30	ALL	NULL	NULL	NULL	NULL	3	Using where
+1	SIMPLE	t7	p30	ALL	NULL	NULL	NULL	NULL	2	Using where
 drop table t7;
 create table t7 (a int unsigned not null) partition by RANGE(a) (
 partition p10 values less than (10),
@@ -243,25 +243,25 @@ id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t7	p10	ALL	NULL	NULL	NULL	NULL	0	Using where
 explain partitions select * from t7 where a <= 10;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t7	p10,p30	ALL	NULL	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t7	p10,p30	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t7 where a = 10;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t7	p30	ALL	NULL	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t7	p30	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t7 where a < 90;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t7	p10,p30,p50,p70,p90	ALL	NULL	NULL	NULL	NULL	3	Using where
 explain partitions select * from t7 where a = 90;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t7		ALL	NULL	NULL	NULL	NULL	3	Using where
+1	SIMPLE	t7		ALL	NULL	NULL	NULL	NULL	0	Using where
 explain partitions select * from t7 where a > 90;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t7		ALL	NULL	NULL	NULL	NULL	3	Using where
+1	SIMPLE	t7		ALL	NULL	NULL	NULL	NULL	0	Using where
 explain partitions select * from t7 where a >= 90;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t7		ALL	NULL	NULL	NULL	NULL	3	Using where
+1	SIMPLE	t7		ALL	NULL	NULL	NULL	NULL	0	Using where
 explain partitions select * from t7 where a > 11 and a < 29;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t7	p30	ALL	NULL	NULL	NULL	NULL	3	Using where
+1	SIMPLE	t7	p30	ALL	NULL	NULL	NULL	NULL	2	Using where
 create table t8 (a date not null) partition by RANGE(YEAR(a)) (
 partition p0 values less than (1980),
 partition p1 values less than (1990),
@@ -270,7 +270,7 @@ partition p2 values less than (2000)
 insert into t8 values ('1985-05-05'),('1995-05-05');
 explain partitions select * from t8 where a < '1980-02-02';
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t8	p0,p1	ALL	NULL	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t8	p0,p1	ALL	NULL	NULL	NULL	NULL	2	Using where
 create table t9 (a date not null) partition by RANGE(TO_DAYS(a)) (
 partition p0 values less than (732299), -- 2004-12-19
 partition p1 values less than (732468), -- 2005-06-06
@@ -295,13 +295,13 @@ partition p2 values less than (9)
 insert into t1 values (1),(2),(3);
 explain partitions select * from t1 where a1 > 3;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p1,p2	ALL	NULL	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t1	p1,p2	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where a1 >= 3;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p1,p2	ALL	NULL	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t1	p1,p2	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where a1 < 3 and a1 > 3;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1		ALL	NULL	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t1		ALL	NULL	NULL	NULL	NULL	0	Using where
 drop table t1;
 create table t3 (a int, b int) 
 partition by list(a) subpartition by hash(b) subpartitions 4 (
@@ -325,7 +325,7 @@ create table t1 (a int) partition by hash(a) partitions 2;
 insert into t1 values (1),(2);
 explain partitions select * from t1 where a is null;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where a is not null;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	p0,p1	ALL	NULL	NULL	NULL	NULL	2	Using where
@@ -342,20 +342,20 @@ id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 explain partitions
 select * from t1 X, t1 Y where X.a = Y.a and (X.a=1 or X.a=2);
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	X	p1,p2	ALL	a	NULL	NULL	NULL	4	Using where
+1	SIMPLE	X	p1,p2	ALL	a	NULL	NULL	NULL	2	Using where
 1	SIMPLE	Y	p1,p2	ref	a	a	4	test.X.a	1	
 drop table t1;
 create table t1 (a int) partition by hash(a) partitions 20;
 insert into t1 values (1),(2),(3);
 explain partitions select * from t1 where a >  1 and a < 3;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p2	ALL	NULL	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t1	p2	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where a >= 1 and a < 3;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	p1,p2	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where a >  1 and a <= 3;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p2,p3	ALL	NULL	NULL	NULL	NULL	3	Using where
+1	SIMPLE	t1	p2,p3	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where a >= 1 and a <= 3;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	p1,p2,p3	ALL	NULL	NULL	NULL	NULL	3	Using where
@@ -371,10 +371,10 @@ partition p3 values in (3)
 insert into t1 values (1,1),(2,2),(3,3);
 explain partitions select * from t1 where b >  1 and b < 3;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0_p0sp2,p1_p1sp2,p2_p2sp2,p3_p3sp2	ALL	NULL	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t1	p0_p0sp2,p1_p1sp2,p2_p2sp2,p3_p3sp2	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where b >  1 and b < 3 and (a =1 or a =2);
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p1_p1sp2,p2_p2sp2	ALL	NULL	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t1	p1_p1sp2,p2_p2sp2	ALL	NULL	NULL	NULL	NULL	2	Using where
 drop table t1;
 create table t1 (a int) partition by list(a) (
 partition p0 values in (1,2),
@@ -445,22 +445,22 @@ id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t2	p0,p1,p2,p3,p4	ALL	NULL	NULL	NULL	NULL	1010	
 explain partitions select * from t2 where a < 801 and a > 200;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t2	p1,p2,p3,p4	ALL	NULL	NULL	NULL	NULL	1010	Using where
+1	SIMPLE	t2	p1,p2,p3,p4	ALL	NULL	NULL	NULL	NULL	800	Using where
 explain partitions select * from t2 where a < 801 and a > 800;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t2	p4	ALL	NULL	NULL	NULL	NULL	1010	Using where
+1	SIMPLE	t2	p4	ALL	NULL	NULL	NULL	NULL	200	Using where
 explain partitions select * from t2 where a > 600;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t2	p3,p4	ALL	NULL	NULL	NULL	NULL	1010	Using where
+1	SIMPLE	t2	p3,p4	ALL	NULL	NULL	NULL	NULL	400	Using where
 explain partitions select * from t2 where a > 600 and b = 1;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t2	p3,p4	ALL	NULL	NULL	NULL	NULL	1010	Using where
+1	SIMPLE	t2	p3,p4	ALL	NULL	NULL	NULL	NULL	400	Using where
 explain partitions select * from t2 where a > 600 and b = 4;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t2	p3,p4	ALL	NULL	NULL	NULL	NULL	1010	Using where
+1	SIMPLE	t2	p3,p4	ALL	NULL	NULL	NULL	NULL	400	Using where
 explain partitions select * from t2 where a > 600 and b = 5;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t2	p3,p4	ALL	NULL	NULL	NULL	NULL	1010	Using where
+1	SIMPLE	t2	p3,p4	ALL	NULL	NULL	NULL	NULL	400	Using where
 explain partitions select * from t2 where b = 5;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t2	p0,p1,p2,p3,p4	ALL	NULL	NULL	NULL	NULL	1010	Using where
@@ -515,19 +515,19 @@ id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t2	p0,p1,p2,p3,p4	ALL	NULL	NULL	NULL	NULL	910	
 explain partitions select * from t2 where a = 101;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t2	p0	ALL	NULL	NULL	NULL	NULL	910	Using where
+1	SIMPLE	t2	p0	ALL	NULL	NULL	NULL	NULL	110	Using where
 explain partitions select * from t2 where a = 550;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t2	p2	ALL	NULL	NULL	NULL	NULL	910	Using where
+1	SIMPLE	t2	p2	ALL	NULL	NULL	NULL	NULL	200	Using where
 explain partitions select * from t2 where a = 833;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t2	p4	ALL	NULL	NULL	NULL	NULL	910	Using where
+1	SIMPLE	t2	p4	ALL	NULL	NULL	NULL	NULL	200	Using where
 explain partitions select * from t2 where (a = 100 OR a = 900);
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t2	p0,p4	ALL	NULL	NULL	NULL	NULL	910	Using where
+1	SIMPLE	t2	p0,p4	ALL	NULL	NULL	NULL	NULL	310	Using where
 explain partitions select * from t2 where (a > 100 AND a < 600);
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t2	p0,p1,p2	ALL	NULL	NULL	NULL	NULL	910	Using where
+1	SIMPLE	t2	p0,p1,p2	ALL	NULL	NULL	NULL	NULL	510	Using where
 analyze table t2;
 Table	Op	Msg_type	Msg_text
 test.t2	analyze	status	OK
@@ -692,7 +692,7 @@ f_int1
 NULL
 explain partitions select * from t1 where f_int1 is null;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	part4_part4sp0	ALL	NULL	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t1	part4_part4sp0	ALL	NULL	NULL	NULL	NULL	2	Using where
 drop table t1;
 create table t1 (a int not null, b int not null)
 partition by list(a) 
@@ -721,10 +721,10 @@ insert into t1 values (1,1),(1,2),(1,3),(1,4),
 (2,1),(2,2),(2,3),(2,4), (NULL,1);
 explain partitions select * from t1 where a IS NULL AND (b=1 OR b=2);
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	pn_pnsp0,pn_pnsp1	ALL	NULL	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t1	pn_pnsp0,pn_pnsp1	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where (a IS NULL or a < 1) AND (b=1 OR b=2);
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	pn_pnsp0,pn_pnsp1	ALL	NULL	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t1	pn_pnsp0,pn_pnsp1	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where (a IS NULL or a < 2) AND (b=1 OR b=2);
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	p0_p0sp0,p0_p0sp1,pn_pnsp0,pn_pnsp1	ALL	NULL	NULL	NULL	NULL	5	Using where
@@ -753,7 +753,7 @@ count(*)
 1
 explain partitions select count(*) from t1 where s1 < 0 or s1 is null;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p3	ALL	NULL	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t1	p3	ALL	NULL	NULL	NULL	NULL	2	Using where
 drop table t1;
 create table t1 (a char(32) primary key)
 partition by key()
@@ -812,24 +812,24 @@ insert into t1 values (18446744073709551000+1);
 insert into t1 values (18446744073709551614-1);
 explain partitions select * from t1 where a < 10;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	1	Using where
+1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 
 where a >= 18446744073709551000-1 and a <= 18446744073709551000+1;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p3,p4	ALL	NULL	NULL	NULL	NULL	4	Using where
+1	SIMPLE	t1	p3,p4	ALL	NULL	NULL	NULL	NULL	3	Using where
 explain partitions select * from t1 
 where a between 18446744073709551001 and 18446744073709551002;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p4	ALL	NULL	NULL	NULL	NULL	4	Using where
+1	SIMPLE	t1	p4	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where a = 18446744073709551000;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p4	ALL	NULL	NULL	NULL	NULL	4	Using where
+1	SIMPLE	t1	p4	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where a = 18446744073709551613;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p4	ALL	NULL	NULL	NULL	NULL	4	Using where
+1	SIMPLE	t1	p4	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where a = 18446744073709551614;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1		ALL	NULL	NULL	NULL	NULL	4	Using where
+1	SIMPLE	t1		ALL	NULL	NULL	NULL	NULL	0	Using where
 drop table t1;
 create table t1 (a int)
 partition by range(a) (
@@ -853,34 +853,34 @@ id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t2	p0	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where a=0xFE;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p2	ALL	NULL	NULL	NULL	NULL	4	Using where
+1	SIMPLE	t1	p2	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t2 where a=0xFE;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t2	p2	ALL	NULL	NULL	NULL	NULL	4	Using where
+1	SIMPLE	t2	p2	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where a > 0xFE AND a <= 0xFF;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1		ALL	NULL	NULL	NULL	NULL	4	Using where
+1	SIMPLE	t1		ALL	NULL	NULL	NULL	NULL	0	Using where
 explain partitions select * from t2 where a > 0xFE AND a <= 0xFF;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t2		ALL	NULL	NULL	NULL	NULL	4	Using where
+1	SIMPLE	t2		ALL	NULL	NULL	NULL	NULL	0	Using where
 explain partitions select * from t1 where a >= 0xFE AND a <= 0xFF;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p2	ALL	NULL	NULL	NULL	NULL	4	Using where
+1	SIMPLE	t1	p2	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t2 where a >= 0xFE AND a <= 0xFF;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t2	p2	ALL	NULL	NULL	NULL	NULL	4	Using where
+1	SIMPLE	t2	p2	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where a < 64 AND a >= 63;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	4	Using where
+1	SIMPLE	t1	p0	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t2 where a < 64 AND a >= 63;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t2	p0	ALL	NULL	NULL	NULL	NULL	4	Using where
+1	SIMPLE	t2	p0	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where a <= 64 AND a >= 63;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0,p1	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t1	p0,p1	ALL	NULL	NULL	NULL	NULL	4	Using where
 explain partitions select * from t2 where a <= 64 AND a >= 63;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t2	p0,p1	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t2	p0,p1	ALL	NULL	NULL	NULL	NULL	4	Using where
 drop table t1;
 drop table t2;
 create table t1(a bigint unsigned not null) partition by range(a+0) (
@@ -898,7 +898,7 @@ id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 explain partitions select * from t1 where 
 a > 0xFFFFFFFFFFFFFFEC and a < 0xFFFFFFFFFFFFFFEE;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1		ALL	NULL	NULL	NULL	NULL	4	Using where
+1	SIMPLE	t1		ALL	NULL	NULL	NULL	NULL	0	Using where
 explain partitions select * from t1 where a>=0 and a <= 0xFFFFFFFFFFFFFFFF;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
 1	SIMPLE	t1	p1,p2,p3,p4	ALL	NULL	NULL	NULL	NULL	8	Using where
--- a/mysql-test/suite/pbxt/r/partition_range.result
+++ b/mysql-test/suite/pbxt/r/partition_range.result
@@ -21,19 +21,19 @@ select * from t1 where a > 1;
 a
 explain partitions select * from t1 where a is null;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	pnull	ALL	NULL	NULL	NULL	NULL	3	Using where
+1	SIMPLE	t1	pnull	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where a >= 0;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0,p1	ALL	NULL	NULL	NULL	NULL	3	Using where
+1	SIMPLE	t1	p0,p1	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where a < 0;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	pnull	ALL	NULL	NULL	NULL	NULL	3	Using where
+1	SIMPLE	t1	pnull	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where a <= 0;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	pnull,p0	ALL	NULL	NULL	NULL	NULL	3	Using where
+1	SIMPLE	t1	pnull,p0	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where a > 1;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1		ALL	NULL	NULL	NULL	NULL	3	Using where
+1	SIMPLE	t1		ALL	NULL	NULL	NULL	NULL	0	Using where
 drop table t1;
 create table t1 (a int unsigned, b int unsigned)
 partition by range (a)
@@ -63,19 +63,19 @@ select * from t1 where a > 1;
 a	b
 explain partitions select * from t1 where a is null;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	pnull_pnullsp0,pnull_pnullsp1	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t1	pnull_pnullsp0,pnull_pnullsp1	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where a >= 0;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	p0_p0sp0,p0_p0sp1,p1_p1sp0,p1_p1sp1	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t1	p0_p0sp0,p0_p0sp1,p1_p1sp0,p1_p1sp1	ALL	NULL	NULL	NULL	NULL	4	Using where
 explain partitions select * from t1 where a < 0;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	pnull_pnullsp0,pnull_pnullsp1	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t1	pnull_pnullsp0,pnull_pnullsp1	ALL	NULL	NULL	NULL	NULL	2	Using where
 explain partitions select * from t1 where a <= 0;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1	pnull_pnullsp0,pnull_pnullsp1,p0_p0sp0,p0_p0sp1	ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t1	pnull_pnullsp0,pnull_pnullsp1,p0_p0sp0,p0_p0sp1	ALL	NULL	NULL	NULL	NULL	4	Using where
 explain partitions select * from t1 where a > 1;
 id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	t1		ALL	NULL	NULL	NULL	NULL	6	Using where
+1	SIMPLE	t1		ALL	NULL	NULL	NULL	NULL	0	Using where
 drop table t1;
 CREATE TABLE t1 (
 a int not null,
--- a/mysql-test/suite/pbxt/r/subselect.result
+++ b/mysql-test/suite/pbxt/r/subselect.result
@@ -3420,18 +3420,20 @@ 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	Using where
+1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	9	
+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);
 a	b
+AAA	8
 BBB	4
 CCC	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	Using where
+1	PRIMARY	SUBQUERY#2	ALL	distinct_key	NULL	NULL	NULL	9	
+1	PRIMARY	t1	ref	a	a	8	SUBQUERY#2.a	1	Using where
 2	SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	9	Using temporary; Using filesort
 DROP TABLE t1;
 create table t1( f1 int,f2 int);
--- a/mysql-test/t/subselect_mat.test
+++ b/mysql-test/t/subselect_mat.test
@@ -75,6 +75,7 @@ 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);
@@ -83,10 +84,12 @@ 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);
@@ -174,6 +177,7 @@ 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
@@ -215,6 +219,7 @@ where (a1, a2) in (select b1, b2 from t2


 # 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
@@ -829,8 +834,12 @@ select min(a1) from t1 where 7 in (select b1 from t2);
 # 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;

 #
--- a/mysql-test/t/subselect_sj2.test
+++ b/mysql-test/t/subselect_sj2.test
@@ -490,6 +490,12 @@ drop table t1, t2;
 # Bug#33062: subquery in stored routine cause crash
 #

+--disable_warnings
+drop procedure if exists p1;
+drop procedure if exists p2;
+drop procedure if exists p3;
+drop procedure if exists p4;
+--enable_warnings
 CREATE TABLE t1(a INT);
 CREATE TABLE t2(c INT);

--- a/sql/item_subselect.cc
+++ b/sql/item_subselect.cc
@@ -190,10 +190,6 @@ bool Item_subselect::fix_fields(THD *thd_param, Item **ref)
    changed= 1;
    inside_first_fix_fields= FALSE;

-
-    // all transformation is done (used by prepared statements)
-    changed= 1;
-
    /*
      Substitute the current item with an Item_in_optimizer that was
      created by Item_in_subselect::select_in_like_transformer and
@@ -217,13 +213,13 @@ bool Item_subselect::fix_fields(THD *thd_param, Item **ref)
      if (!(*ref)->fixed)
 	res= (*ref)->fix_fields(thd, ref);
      goto end;
-//psergey-merge:  done_first_fix_fields= FALSE;
+
    }
    // Is it one field subselect?
    if (engine->cols() > max_columns)
    {
      my_error(ER_OPERAND_COLUMNS, MYF(0), 1);
-//psergey-merge:  done_first_fix_fields= FALSE;
+
      goto end;
    }
    fix_length_and_dec();
@@ -241,6 +237,7 @@ bool Item_subselect::fix_fields(THD *thd_param, Item **ref)

 end:
  done_first_fix_fields= FALSE;
+  inside_first_fix_fields= FALSE;
  thd->where= save_where;
  return res;
 }
@@ -468,6 +465,12 @@ bool Item_subselect::exec()
  return (res);
 }

+int Item_subselect::optimize()
+{
+  int res;
+  res= engine->optimize();
+  return res;
+}

 /*
  Compute the IN predicate if the left operand's cache changed.
@@ -724,9 +727,6 @@ Item_singlerow_subselect::select_transformer(JOIN *join)
 void Item_singlerow_subselect::store(uint i, Item *item)
 {
  row[i]->store(item);
-  //psergey-merge: can do without that: row[i]->cache_value();
-  //psergey-backport-timours: ^ really, without that ^ 
-  //psergey-try-merge-again:
  row[i]->cache_value();
 }

@@ -2088,7 +2088,7 @@ void Item_in_subselect::update_used_tables()
    @retval FALSE an execution method was chosen successfully
 */

-bool Item_in_subselect::setup_engine()
+bool Item_in_subselect::setup_engine(bool dont_switch_arena)
 {
  subselect_hash_sj_engine *new_engine= NULL;
  bool res= FALSE;
@@ -2103,14 +2103,15 @@ bool Item_in_subselect::setup_engine()

    old_engine= (subselect_single_select_engine*) engine;

-    if (arena->is_conventional())
+    if (arena->is_conventional() || dont_switch_arena)
      arena= 0;
    else
      thd->set_n_backup_active_arena(arena, &backup);

    if (!(new_engine= new subselect_hash_sj_engine(thd, this,
                                                   old_engine)) ||
-        new_engine->init_permanent(unit->get_unit_column_types()))
+        new_engine->init_permanent(unit->get_unit_column_types(),
+                                   old_engine->get_identifier()))
    {
      Item_subselect::trans_res trans_res;
      /*
@@ -3457,7 +3458,7 @@ subselect_hash_sj_engine::get_strategy_using_schema()
        bitmap_set_bit(&partial_match_key_parts, i);
        ++count_partial_match_columns;
      }
-    }
+    };
  }

  /* If no column contains NULLs use regular hash index lookups. */
@@ -3656,6 +3657,7 @@ bitmap_init_memroot(MY_BITMAP *map, uint n_bits, MEM_ROOT *mem_root)
  reexecution.

  @param tmp_columns the items that produce the data for the temp table
+  @param subquery_id subquery's identifier (for temptable name)

  @details
  - Create a temporary table to store the result of the IN subquery. The
@@ -3671,7 +3673,8 @@ bitmap_init_memroot(MY_BITMAP *map, uint n_bits, MEM_ROOT *mem_root)
  @retval FALSE otherwise
 */

-bool subselect_hash_sj_engine::init_permanent(List<Item> *tmp_columns)
+bool subselect_hash_sj_engine::init_permanent(List<Item> *tmp_columns, 
+                                              uint subquery_id)
 {
  /* Options to create_tmp_table. */
  ulonglong tmp_create_options= thd->options | TMP_TABLE_ALL_COLUMNS;
@@ -3706,12 +3709,19 @@ bool subselect_hash_sj_engine::init_permanent(List<Item> *tmp_columns)
    DBUG_RETURN(TRUE);
  }
 */
+  char buf[32];
+  uint len= my_snprintf(buf, sizeof(buf), "SUBQUERY#%d", subquery_id);
+  char *name;
+  if (!(name= (char*)thd->alloc(len + 1)))
+    DBUG_RETURN(TRUE);
+  memcpy(name, buf, len+1);
+
  if (!(result= new select_materialize_with_stats))
    DBUG_RETURN(TRUE);

  if (((select_union*) result)->create_result_table(
                         thd, tmp_columns, TRUE, tmp_create_options,
-                         "materialized subselect", TRUE))
+                         name, TRUE))
    DBUG_RETURN(TRUE);

  tmp_table= ((select_union*) result)->table;
@@ -3792,7 +3802,7 @@ bool subselect_hash_sj_engine::make_semi_join_conds()
  if (!(tmp_table_ref= (TABLE_LIST*) thd->alloc(sizeof(TABLE_LIST))))
    DBUG_RETURN(TRUE);

-  tmp_table_ref->init_one_table("", "materialized subselect", TL_READ);
+  tmp_table_ref->init_one_table("", tmp_table->alias, TL_READ);
  tmp_table_ref->table= tmp_table;

  context= new Name_resolution_context;
@@ -3971,6 +3981,17 @@ void subselect_hash_sj_engine::cleanup()
 }


+int subselect_hash_sj_engine::optimize()
+{
+  int res= 0;
+  SELECT_LEX *save_select= thd->lex->current_select;
+  thd->lex->current_select= materialize_join->select_lex;
+  res= materialize_join->optimize();
+  thd->lex->current_select= save_select;
+
+  return res;
+}
+
 /**
  Execute a subquery IN predicate via materialization.

--- a/sql/item_subselect.h
+++ b/sql/item_subselect.h
@@ -46,15 +46,16 @@ public:
          < child_join->prepare
        < engine->prepare
        *ref= substitution;
+        substitution= NULL;
      < Item_subselect::fix_fields
  */
  Item *substitution;
 public:
  /* unit of subquery */
  st_select_lex_unit *unit;
-protected:
  /* engine that perform execution of subselect (single select or union) */
  subselect_engine *engine;
+protected:
  /* old engine if engine was changed */
  subselect_engine *old_engine;
  /* cache of used external tables */
@@ -139,6 +140,7 @@ public:
  bool mark_as_dependent(THD *thd, st_select_lex *select, Item *item);
  void fix_after_pullout(st_select_lex *new_parent, Item **ref);
  void recalc_used_tables(st_select_lex *new_parent, bool after_pullout);
+  virtual int optimize();
  virtual bool exec();
  virtual void fix_length_and_dec();
  table_map used_tables() const;
@@ -333,7 +335,9 @@ protected:
    all JOIN in UNION
  */
  Item *expr;
+public:
  Item_in_optimizer *optimizer;
+protected:
  bool was_null;
  bool abort_on_null;
 public:
@@ -379,6 +383,23 @@ public:
  };
  enum_exec_method exec_method;

+  /*
+    JTBM: temporary measure to tell JTBM predicates from SJ predicates
+    psergey-jtbm-todo: can't we do without this?
+     - either remove it altogether
+     - or put into enum_exec_method
+    
+    We can't remove it altogether as it is used to classify contents in
+    join->sj_subselects.
+    jtbm-todo: option 1: let sj_subselects list pairs.
+  */
+  bool is_flattenable_semijoin;
+  
+  /*
+    Cost to populate the temporary table (set on if-needed basis).
+  */
+  //double startup_cost;
+
  bool *get_cond_guard(int i)
  {
    return pushed_cond_guards ? pushed_cond_guards + i : NULL;
@@ -428,7 +449,7 @@ public:
  bool fix_fields(THD *thd, Item **ref);
  void fix_after_pullout(st_select_lex *new_parent, Item **ref);
  void update_used_tables();
-  bool setup_engine();
+  bool setup_engine(bool dont_switch_arena);
  bool init_left_expr_cache();
  /* Inform 'this' that it was computed, and contains a valid result. */
  void set_first_execution() { if (first_execution) first_execution= FALSE; }
@@ -502,6 +523,7 @@ public:
  THD * get_thd() { return thd; }
  virtual int prepare()= 0;
  virtual void fix_length_and_dec(Item_cache** row)= 0;
+  virtual int optimize() { DBUG_ASSERT(0); return 0; }
  /*
    Execute the engine

@@ -734,7 +756,7 @@ inline bool Item_subselect::is_uncacheable() const

 class subselect_hash_sj_engine : public subselect_engine
 {
-protected:
+public:
  /* The table into which the subquery is materialized. */
  TABLE *tmp_table;
  /* TRUE if the subquery was materialized into a temp table. */
@@ -746,14 +768,16 @@ protected:
    of subselect_single_select_engine::[prepare | cols].
  */
  subselect_single_select_engine *materialize_engine;
+protected:
  /* The engine used to compute the IN predicate. */
  subselect_engine *lookup_engine;
  /*
    QEP to execute the subquery and materialize its result into a
    temporary table. Created during the first call to exec().
  */
+public:
  JOIN *materialize_join;
-
+protected:
  /* Keyparts of the only non-NULL composite index in a rowid merge. */
  MY_BITMAP non_null_key_parts;
  /* Keyparts of the single column indexes with NULL, one keypart per index. */
@@ -766,7 +790,9 @@ protected:
    IN results because index lookups sometimes match values that are actually
    not equal to the search key in SQL terms.
 */
+public:
  Item_cond_and *semi_join_conds;
+protected:
  /* Possible execution strategies that can be used to compute hash semi-join.*/
  enum exec_strategy {
    UNDEFINED,
@@ -802,10 +828,11 @@ public:
  }
  ~subselect_hash_sj_engine();

-  bool init_permanent(List<Item> *tmp_columns);
+  bool init_permanent(List<Item> *tmp_columns, uint subquery_id);
  bool init_runtime();
  void cleanup();
  int prepare() { return 0; } /* Override virtual function in base class. */
+  int optimize();
  int exec();
  virtual void print(String *str, enum_query_type query_type);
  uint cols()
--- a/sql/opt_range.cc
+++ b/sql/opt_range.cc
@@ -2285,7 +2285,8 @@ int SQL_SELECT::test_quick_select(THD *thd, key_map keys_to_use,
  quick=0;
  needed_reg.clear_all();
  quick_keys.clear_all();
-  if (keys_to_use.is_clear_all())
+  DBUG_ASSERT(!head->is_filled_at_execution());
+  if (keys_to_use.is_clear_all() || head->is_filled_at_execution())
    DBUG_RETURN(0);
  records= head->file->stats.records;
  if (!records)
--- a/sql/opt_subselect.cc
+++ b/sql/opt_subselect.cc
@@ -2,7 +2,7 @@
  @file

  @brief
-    Subquery optimization code here.
+    Semi-join subquery optimizations code

 */

@@ -16,7 +16,6 @@

 #include <my_bit.h>

-// Our own:
 static
 bool subquery_types_allow_materialization(Item_in_subselect *in_subs);
 static bool replace_where_subcondition(JOIN *join, Item **expr, 
@@ -25,6 +24,8 @@ static bool replace_where_subcondition(JOIN *join, Item **expr,
 static int subq_sj_candidate_cmp(Item_in_subselect* const *el1, 
                                 Item_in_subselect* const *el2);
 static bool convert_subq_to_sj(JOIN *parent_join, Item_in_subselect *subq_pred);
+static bool convert_subq_to_jtbm(JOIN *parent_join, 
+                                 Item_in_subselect *subq_pred, bool *remove);
 static TABLE_LIST *alloc_join_nest(THD *thd);
 static 
 void fix_list_after_tbl_changes(SELECT_LEX *new_parent, List<TABLE_LIST> *tlist);
@@ -50,17 +51,22 @@ static void remove_subq_pushed_predicates(JOIN *join, Item **where);
 /*
  Check if we need JOIN::prepare()-phase subquery rewrites and if yes, do them

+  SYNOPSIS
+     check_and_do_in_subquery_rewrites()
+       join  Subquery's join
+
  DESCRIPTION
    Check if we need to do
-     - subquery->semi-join rewrite
+     - subquery -> mergeable semi-join rewrite
     - if the subquery can be handled with materialization
     - 'substitution' rewrite for table-less subqueries like "(select 1)"
-
-    and mark appropriately
+     - IN->EXISTS rewrite
+    and, depending on the rewrite, either do it, or record it to be done at a
+    later phase.

  RETURN
    0      - OK
-    -1  - Some sort of query error
+    Other  - Some sort of query error
 */

 int check_and_do_in_subquery_rewrites(JOIN *join)
@@ -166,6 +172,7 @@ int check_and_do_in_subquery_rewrites(JOIN *join)
      (void)subquery_types_allow_materialization(in_subs);

      in_subs->emb_on_expr_nest= thd->thd_marker.emb_on_expr_nest;
+      in_subs->is_flattenable_semijoin= TRUE;

      /* Register the subquery for further processing in flatten_subqueries() */
      select_lex->
@@ -220,10 +227,23 @@ int check_and_do_in_subquery_rewrites(JOIN *join)
          (in_subs->is_top_level_item() ||
           optimizer_flag(thd, OPTIMIZER_SWITCH_PARTIAL_MATCH_ROWID_MERGE) ||
           optimizer_flag(thd, OPTIMIZER_SWITCH_PARTIAL_MATCH_TABLE_SCAN)) &&//4
-          !in_subs->is_correlated &&                                  // 5
-          in_subs->exec_method == Item_in_subselect::NOT_TRANSFORMED) // 6
+          !in_subs->is_correlated)                                  // 5
      {
+        if (in_subs->exec_method == Item_in_subselect::NOT_TRANSFORMED)
          in_subs->exec_method= Item_in_subselect::MATERIALIZATION;
+
+        /*
+          If the subquery is an AND-part of WHERE register for being processed
+          with jtbm strategy
+        */
+        if (in_subs->exec_method == Item_in_subselect::MATERIALIZATION &&
+            thd->thd_marker.emb_on_expr_nest == (TABLE_LIST*)0x1)
+        {
+          in_subs->emb_on_expr_nest= thd->thd_marker.emb_on_expr_nest;
+          in_subs->is_flattenable_semijoin= FALSE;
+          select_lex->outer_select()->
+            join->sj_subselects.append(thd->mem_root, in_subs);
+        }
      }

      Item_subselect::trans_res trans_res;
@@ -338,6 +358,69 @@ bool subquery_types_allow_materialization(Item_in_subselect *in_subs)
 }


+/*
+  Finalize IN->EXISTS conversion in case we couldn't use materialization.
+
+  DESCRIPTION  Invoke the IN->EXISTS converter
+    Replace the Item_in_subselect with its wrapper Item_in_optimizer in WHERE.
+
+  RETURN 
+    FALSE - Ok
+    TRUE  - Fatal error
+*/
+
+static 
+bool make_in_exists_conversion(THD *thd, JOIN *join, Item_in_subselect *item)
+{
+  DBUG_ENTER("make_in_exists_conversion");
+  JOIN *child_join= item->unit->first_select()->join;
+  Item_subselect::trans_res res;
+  item->changed= 0;
+  item->fixed= 0;
+
+  SELECT_LEX *save_select_lex= thd->lex->current_select;
+  thd->lex->current_select= item->unit->first_select();
+
+  res= item->select_transformer(child_join);
+
+  thd->lex->current_select= save_select_lex;
+
+  if (res == Item_subselect::RES_ERROR)
+    DBUG_RETURN(TRUE);
+
+  item->changed= 1;
+  item->fixed= 1;
+
+  Item *substitute= item->substitution;
+  bool do_fix_fields= !item->substitution->fixed;
+  /*
+    The Item_subselect has already been wrapped with Item_in_optimizer, so we
+    should search for item->optimizer, not 'item'.
+  */
+  Item *replace_me= item->optimizer;
+  DBUG_ASSERT(replace_me==substitute);
+
+  Item **tree= (item->emb_on_expr_nest == (TABLE_LIST*)1)?
+                 &join->conds : &(item->emb_on_expr_nest->on_expr);
+  if (replace_where_subcondition(join, tree, replace_me, substitute, 
+                                 do_fix_fields))
+    DBUG_RETURN(TRUE);
+  item->substitution= NULL;
+   
+  if (!thd->stmt_arena->is_conventional())
+  {
+    tree= (item->emb_on_expr_nest == (TABLE_LIST*)1)?
+           &join->select_lex->prep_where : 
+           &(item->emb_on_expr_nest->prep_on_expr);
+
+    if (replace_where_subcondition(join, tree, replace_me, substitute, 
+                                   FALSE))
+      DBUG_RETURN(TRUE);
+  }
+  DBUG_RETURN(FALSE);
+}
+
+
 /*
  Convert semi-join subquery predicates into semi-join join nests

@@ -445,26 +528,42 @@ bool convert_join_subqueries_to_semijoins(JOIN *join)
  // #tables-in-parent-query + #tables-in-subquery < MAX_TABLES
  /* Replace all subqueries to be flattened with Item_int(1) */
  arena= thd->activate_stmt_arena_if_needed(&backup);
-  for (in_subq= join->sj_subselects.front(); 
-       in_subq != in_subq_end && 
-       join->tables + (*in_subq)->unit->first_select()->join->tables < MAX_TABLES;
-       in_subq++)
-  {
-    Item **tree= ((*in_subq)->emb_on_expr_nest == (TABLE_LIST*)1)?
-                   &join->conds : &((*in_subq)->emb_on_expr_nest->on_expr);
-    if (replace_where_subcondition(join, tree, *in_subq, new Item_int(1),
-                                   FALSE))
-      DBUG_RETURN(TRUE); /* purecov: inspected */
-  }
 
  for (in_subq= join->sj_subselects.front(); 
       in_subq != in_subq_end && 
       join->tables + (*in_subq)->unit->first_select()->join->tables < MAX_TABLES;
       in_subq++)
+  {
+    bool remove_item= TRUE;
+    if ((*in_subq)->is_flattenable_semijoin) 
    {
      if (convert_subq_to_sj(join, *in_subq))
        DBUG_RETURN(TRUE);
    }
+    else
+    {
+      if (convert_subq_to_jtbm(join, *in_subq, &remove_item))
+        DBUG_RETURN(TRUE);
+    }
+    if (remove_item)
+    {
+      Item **tree= ((*in_subq)->emb_on_expr_nest == (TABLE_LIST*)1)?
+                     &join->conds : &((*in_subq)->emb_on_expr_nest->on_expr);
+      Item *replace_me= *in_subq;
+      /*
+        JTBM: the subquery was already mapped with Item_in_optimizer, so we
+        should search for that, not for original Item_in_subselect.
+        TODO: what about delaying that rewrite until here?
+      */
+      if (!(*in_subq)->is_flattenable_semijoin)
+      {
+        replace_me= (*in_subq)->optimizer;
+      }
+      if (replace_where_subcondition(join, tree, replace_me, new Item_int(1),
+                                     FALSE))
+        DBUG_RETURN(TRUE); /* purecov: inspected */
+    }
+  }
 skip_conversion:
  /* 
    3. Finalize (perform IN->EXISTS rewrite) the subqueries that we didn't
@@ -494,7 +593,19 @@ skip_conversion:
    bool do_fix_fields= !(*in_subq)->substitution->fixed;
    Item **tree= ((*in_subq)->emb_on_expr_nest == (TABLE_LIST*)1)?
                   &join->conds : &((*in_subq)->emb_on_expr_nest->on_expr);
-    if (replace_where_subcondition(join, tree, *in_subq, substitute, 
+
+    Item *replace_me= *in_subq;
+    /*
+      JTBM: the subquery was already mapped with Item_in_optimizer, so we
+      should search for that, not for original Item_in_subselect.
+      TODO: what about delaying that rewrite until here?
+    */
+    if (!(*in_subq)->is_flattenable_semijoin)
+    {
+      replace_me= (*in_subq)->optimizer;
+    }
+
+    if (replace_where_subcondition(join, tree, replace_me, substitute, 
                                   do_fix_fields))
      DBUG_RETURN(TRUE);
    (*in_subq)->substitution= NULL;
@@ -505,7 +616,7 @@ skip_conversion:
             &join->select_lex->prep_where : 
             &((*in_subq)->emb_on_expr_nest->prep_on_expr);

-      if (replace_where_subcondition(join, tree, *in_subq, substitute, 
+      if (replace_where_subcondition(join, tree, replace_me, substitute, 
                                     FALSE))
        DBUG_RETURN(TRUE);
    }
@@ -517,6 +628,61 @@ skip_conversion:
  DBUG_RETURN(FALSE);
 }

+
+/*
+  Get #output_rows and scan_time estimates for a "delayed" table.
+
+  SYNOPSIS
+    get_delayed_table_estimates()
+      table         IN    Table to get estimates for
+      out_rows      OUT   E(#rows in the table)
+      scan_time     OUT   E(scan_time).
+      startup_cost  OUT   cost to populate the table.
+
+  DESCRIPTION
+    Get #output_rows and scan_time estimates for a "delayed" table. By
+    "delayed" here we mean that the table is filled at the start of query
+    execution. This means that the optimizer can't use table statistics to 
+    get #rows estimate for it, it has to call this function instead.
+
+    This function is expected to make different actions depending on the nature
+    of the table. At the moment there is only one kind of delayed tables,
+    non-flattenable semi-joins.
+*/
+
+void get_delayed_table_estimates(TABLE *table,
+                                 ha_rows *out_rows, 
+                                 double *scan_time,
+                                 double *startup_cost)
+{
+  Item_in_subselect *item= table->pos_in_table_list->jtbm_subselect;
+  item->optimize();
+
+  DBUG_ASSERT(item->engine->engine_type() ==
+              subselect_engine::HASH_SJ_ENGINE);
+
+  subselect_hash_sj_engine *hash_sj_engine=
+    ((subselect_hash_sj_engine*)item->engine);
+  JOIN *join= hash_sj_engine->materialize_join;
+
+  double rows= 1;
+  double read_time= 0.0;
+
+  /* Calculate #rows and cost of join execution */
+  for (uint i= join->const_tables; i < join->tables; i++)
+  {
+    rows      *= join->best_positions[i].records_read;
+    read_time += join->best_positions[i].read_time;
+  }
+  *out_rows= rows;
+  *startup_cost= read_time;
+  /* Calculate cost of scanning the temptable */
+  double data_size= rows * hash_sj_engine->tmp_table->s->reclength;
+  /* Do like in handler::read_time */
+  *scan_time= data_size/IO_SIZE + 2;
+} 
+
+
 /**
   @brief Replaces an expression destructively inside the expression tree of
   the WHERE clase.
@@ -534,6 +700,7 @@ skip_conversion:
   @return <code>true</code> if there was an error, <code>false</code> if
   successful.
 */
+
 static bool replace_where_subcondition(JOIN *join, Item **expr, 
                                       Item *old_cond, Item *new_cond,
                                       bool do_fix_fields)
@@ -769,8 +936,7 @@ static bool convert_subq_to_sj(JOIN *parent_join, Item_in_subselect *subq_pred)
  /* 3. Remove the original subquery predicate from the WHERE/ON */

  // The subqueries were replaced for Item_int(1) earlier
-  subq_pred->exec_method=
-    Item_in_subselect::SEMI_JOIN;         // for subsequent executions
+  subq_pred->exec_method= Item_in_subselect::SEMI_JOIN; // for subsequent executions
  /*TODO: also reset the 'with_subselect' there. */

  /* n. Adjust the parent_join->tables counter */
@@ -887,6 +1053,118 @@ static bool convert_subq_to_sj(JOIN *parent_join, Item_in_subselect *subq_pred)
  DBUG_RETURN(FALSE);
 }

+
+/*
+  Convert subquery predicate into non-mergeable semi-join nest.
+
+  TODO: 
+    why does this do IN-EXISTS conversion? Can't we unify it with mergeable
+    semi-joins? currently, convert_subq_to_sj() cannot fail to convert (unless
+    fatal errors)
+
+    
+  RETURN 
+    FALSE - Ok
+    TRUE  - Fatal error
+*/
+
+static bool convert_subq_to_jtbm(JOIN *parent_join, 
+                                 Item_in_subselect *subq_pred, 
+                                 bool *remove_item)
+{
+  SELECT_LEX *parent_lex= parent_join->select_lex;
+  List<TABLE_LIST> *emb_join_list= &parent_lex->top_join_list;
+  TABLE_LIST *emb_tbl_nest= NULL; // will change when we learn to handle outer joins
+  TABLE_LIST *tl;
+  DBUG_ENTER("convert_subq_to_jtbm");
+
+  if (subq_pred->setup_engine(TRUE))
+    DBUG_RETURN(TRUE);
+
+  if (subq_pred->engine->engine_type() != subselect_engine::HASH_SJ_ENGINE)
+  {
+    *remove_item= FALSE;
+    make_in_exists_conversion(parent_join->thd, parent_join, subq_pred);
+    DBUG_RETURN(FALSE);
+  }
+  *remove_item= TRUE;
+
+  TABLE_LIST *jtbm;
+  char *tbl_alias;
+  const char alias_mask[]="SUBQUERY#%d";
+  if (!(tbl_alias= (char*)parent_join->thd->calloc(sizeof(alias_mask)+5)) || 
+      !(jtbm= alloc_join_nest(parent_join->thd))) //todo: this is not a join nest!
+  {
+    DBUG_RETURN(TRUE);
+  }
+
+  jtbm->join_list= emb_join_list;
+  jtbm->embedding= emb_tbl_nest;
+  jtbm->jtbm_subselect= subq_pred;
+  jtbm->nested_join= NULL;
+
+  /* Nests do not participate in those 'chains', so: */
+  /* jtbm->next_leaf= jtbm->next_local= jtbm->next_global == NULL*/
+  emb_join_list->push_back(jtbm);
+  
+  /* 
+    Inject the jtbm table into TABLE_LIST::next_leaf list, so that 
+    make_join_statistics() and co. can find it.
+  */
+  for (tl= parent_lex->leaf_tables; tl->next_leaf; tl= tl->next_leaf) ;
+  tl->next_leaf= jtbm;
+
+  /*
+    Same as above for TABLE_LIST::next_local chain
+    (a theory: a next_local chain always starts with ::leaf_tables
+     because view's tables are inserted after the view)
+  */
+  for (tl= parent_lex->leaf_tables; tl->next_local; tl= tl->next_local) ;
+  tl->next_local= jtbm;
+
+  /* A theory: no need to re-connect the next_global chain */
+
+  subselect_hash_sj_engine *hash_sj_engine=
+    ((subselect_hash_sj_engine*)subq_pred->engine);
+  jtbm->table= hash_sj_engine->tmp_table;
+
+  jtbm->table->tablenr= parent_join->tables;
+  jtbm->table->map= table_map(1) << (parent_join->tables);
+
+  parent_join->tables++;
+
+  Item *conds= hash_sj_engine->semi_join_conds;
+  conds->fix_after_pullout(parent_lex, &conds);
+
+  DBUG_EXECUTE("where", print_where(conds,"SJ-EXPR", QT_ORDINARY););
+  
+  my_snprintf(tbl_alias, sizeof(alias_mask)+5, alias_mask, 
+    hash_sj_engine->materialize_join->select_lex->select_number);
+  jtbm->alias= tbl_alias; 
+
+  /* Inject sj_on_expr into the parent's WHERE or ON */
+  if (emb_tbl_nest)
+  {
+    DBUG_ASSERT(0);
+    /*emb_tbl_nest->on_expr= and_items(emb_tbl_nest->on_expr, 
+                                     sj_nest->sj_on_expr);
+    emb_tbl_nest->on_expr->fix_fields(parent_join->thd, &emb_tbl_nest->on_expr);
+    */
+  }
+  else
+  {
+    /* Inject into the WHERE */
+    parent_join->conds= and_items(parent_join->conds, conds);
+    parent_join->conds->fix_fields(parent_join->thd, &parent_join->conds);
+    parent_join->select_lex->where= parent_join->conds;
+  }
+
+  /* Don't unlink the child subselect, as the subquery will be used. */
+
+  DBUG_RETURN(FALSE);
+}
+
+
 static TABLE_LIST *alloc_join_nest(THD *thd)
 {
  TABLE_LIST *tbl;
@@ -1245,6 +1523,7 @@ bool optimize_semijoin_nests(JOIN *join, table_map all_table_map)
  DBUG_RETURN(FALSE);
 }

+
 /*
  Get estimated record length for semi-join materialization temptable
  
@@ -1301,7 +1580,7 @@ static uint get_tmp_table_rec_length(List<Item> &items)
  return len;
 }

-//psergey-todo: is the below a kind of table elimination??
+
 /*
  Check if table's KEYUSE elements have an eq_ref(outer_tables) candidate

@@ -1318,6 +1597,8 @@ static uint get_tmp_table_rec_length(List<Item> &items)
    Check again if it is feasible to factor common parts with constant table
    search

+    Also check if it's feasible to factor common parts with table elimination
+
  RETURN
    TRUE  - There exists an eq_ref(outer-tables) candidate
    FALSE - Otherwise
@@ -1368,6 +1649,7 @@ bool find_eq_ref_candidate(TABLE *table, table_map sj_inner_tables)
  return FALSE;
 }

+
 /*
  Do semi-join optimization step after we've added a new tab to join prefix

@@ -3504,3 +3786,26 @@ static void remove_subq_pushed_predicates(JOIN *join, Item **where)
 }


+bool do_jtbm_materialization_if_needed(JOIN_TAB *tab)
+{
+  Item_in_subselect *in_subs;
+  if (tab->table->pos_in_table_list && 
+      (in_subs= tab->table->pos_in_table_list->jtbm_subselect))
+  {
+    DBUG_ASSERT(in_subs->engine->engine_type() ==
+                subselect_engine::HASH_SJ_ENGINE);
+
+    subselect_hash_sj_engine *hash_sj_engine=
+      ((subselect_hash_sj_engine*)in_subs->engine);
+    if (!hash_sj_engine->is_materialized)
+    {
+      hash_sj_engine->materialize_join->exec();
+      hash_sj_engine->is_materialized= TRUE; 
+
+      if (hash_sj_engine->materialize_join->error || tab->join->thd->is_fatal_error)
+        return TRUE;
+    }
+  }
+  return FALSE;
+}
+
--- a/sql/opt_subselect.h
+++ b/sql/opt_subselect.h
@@ -1,4 +1,6 @@
-/* */
+/*
+  Semi-join subquery optimization code definitions
+*/

 #ifdef USE_PRAGMA_INTERFACE
 #pragma interface			/* gcc class implementation */
@@ -365,4 +367,10 @@ int clear_sj_tmp_tables(JOIN *join);
 int rewrite_to_index_subquery_engine(JOIN *join);


+void get_delayed_table_estimates(TABLE *table,
+                                 ha_rows *out_rows, 
+                                 double *scan_time,
+                                 double *startup_cost);
+
+bool do_jtbm_materialization_if_needed(JOIN_TAB *tab);

--- a/sql/sql_base.cc
+++ b/sql/sql_base.cc
@@ -7661,6 +7661,17 @@ bool setup_tables(THD *thd, Name_resolution_context *context,
      if (res)
        DBUG_RETURN(1);
    }
+    if (table_list->jtbm_subselect)
+    {
+      Item *item= table_list->jtbm_subselect;
+      if (item->fix_fields(thd, &item))
+      {
+        my_error(ER_TOO_MANY_TABLES,MYF(0),MAX_TABLES);
+        DBUG_RETURN(1);
+      }
+      DBUG_ASSERT(item == table_list->jtbm_subselect);
+      table_list->jtbm_subselect->setup_engine(FALSE);
+    }
  }

  /* Precompute and store the row types of NATURAL/USING joins. */
--- a/sql/sql_join_cache.cc
+++ b/sql/sql_join_cache.cc
@@ -33,7 +33,6 @@

 #define NO_MORE_RECORDS_IN_BUFFER  (uint)(-1)

-
 /*****************************************************************************
 *  Join cache module
 ******************************************************************************/
@@ -1778,6 +1777,13 @@ enum_nested_loop_state JOIN_CACHE_BNL::join_matching_records(bool skip_last)
  }

  /* Start retrieving all records of the joined table */
+  
+  if (do_jtbm_materialization_if_needed(join_tab))
+  {
+    rc= NESTED_LOOP_ERROR;
+    goto finish;
+  }
+
  if ((error= join_init_read_record(join_tab))) 
  {
    rc= error < 0 ? NESTED_LOOP_NO_MORE_ROWS: NESTED_LOOP_ERROR;
--- a/sql/sql_select.cc
+++ b/sql/sql_select.cc
@@ -2445,7 +2445,7 @@ bool JOIN::setup_subquery_materialization()
      {
        Item_in_subselect *in_subs= (Item_in_subselect*) subquery_predicate;
        if (in_subs->exec_method == Item_in_subselect::MATERIALIZATION &&
-            in_subs->setup_engine())
+            in_subs->setup_engine(FALSE))
          return TRUE;
      }
    }
@@ -2531,9 +2531,10 @@ make_join_statistics(JOIN *join, TABLE_LIST *tables_arg, COND *conds,
  DBUG_ENTER("make_join_statistics");

  table_count=join->tables;
-  stat=(JOIN_TAB*) join->thd->calloc(sizeof(JOIN_TAB)*table_count);
+
+  stat=(JOIN_TAB*) join->thd->calloc(sizeof(JOIN_TAB)*(table_count));
  stat_ref=(JOIN_TAB**) join->thd->alloc(sizeof(JOIN_TAB*)*MAX_TABLES);
-  table_vector=(TABLE**) join->thd->alloc(sizeof(TABLE*)*(table_count*2));
+  table_vector=(TABLE**) join->thd->alloc(sizeof(TABLE*)*((table_count)*2));
  if (!stat || !stat_ref || !table_vector)
    DBUG_RETURN(1);				// Eom /* purecov: inspected */

@@ -2565,7 +2566,7 @@ make_join_statistics(JOIN *join, TABLE_LIST *tables_arg, COND *conds,
    table->reginfo.join_tab=s;
    table->reginfo.not_exists_optimize=0;
    bzero((char*) table->const_key_parts, sizeof(key_part_map)*table->s->keys);
-    all_table_map|= table->map;
+    all_table_map|= s->table->map;
    s->join=join;
    s->info=0;					// For describe

@@ -2580,9 +2581,11 @@ make_join_statistics(JOIN *join, TABLE_LIST *tables_arg, COND *conds,
    {
      /* s is the only inner table of an outer join */
 #ifdef WITH_PARTITION_STORAGE_ENGINE
-      if ((!table->file->stats.records || table->no_partitions_used) && !embedding)
+      if (!table->is_filled_at_execution() &&
+           (!table->file->stats.records || table->no_partitions_used) && !embedding)
 #else
-      if (!table->file->stats.records && !embedding)
+      if (!table->is_filled_at_execution() &&
+          !table->file->stats.records && !embedding)
 #endif
      {						// Empty table
        s->dependent= 0;                        // Ignore LEFT JOIN depend.
@@ -2616,7 +2619,8 @@ make_join_statistics(JOIN *join, TABLE_LIST *tables_arg, COND *conds,
 #else
    const bool no_partitions_used= FALSE;
 #endif
-    if ((table->s->system || table->file->stats.records <= 1 ||
+    if (!table->is_filled_at_execution() && 
+        (table->s->system || table->file->stats.records <= 1 ||
         no_partitions_used) &&
 	!s->dependent &&
 	(table->file->ha_table_flags() & HA_STATS_RECORDS_IS_EXACT) &&
@@ -2626,6 +2630,7 @@ make_join_statistics(JOIN *join, TABLE_LIST *tables_arg, COND *conds,
      no_rows_const_tables |= table->map;
    }
  }
+
  stat_vector[i]=0;
  join->outer_join=outer_join;

@@ -2714,6 +2719,9 @@ make_join_statistics(JOIN *join, TABLE_LIST *tables_arg, COND *conds,
    {
      table=s->table;

+      if (table->is_filled_at_execution())
+        continue;
+
      /* 
        If equi-join condition by a key is null rejecting and after a
        substitution of a const table the key value happens to be null
@@ -2866,6 +2874,7 @@ make_join_statistics(JOIN *join, TABLE_LIST *tables_arg, COND *conds,

  for (s=stat ; s < stat_end ; s++)
  {
+    s->startup_cost= 0;
    if (s->type == JT_SYSTEM || s->type == JT_CONST)
    {
      /* Only one matching row */
@@ -2873,8 +2882,20 @@ make_join_statistics(JOIN *join, TABLE_LIST *tables_arg, COND *conds,
      continue;
    }
    /* Approximate found rows and time to read them */
-    s->found_records=s->records=s->table->file->stats.records;
-    s->read_time=(ha_rows) s->table->file->scan_time();
+
+    if (s->table->is_filled_at_execution())
+    {
+      get_delayed_table_estimates(s->table, &s->records, &s->read_time,
+                                  &s->startup_cost);
+      s->found_records= s->records;
+      table->quick_condition_rows=s->records;
+    }
+    else
+    {
+      s->found_records= s->records= s->table->file->stats.records;
+      s->read_time= s->table->file->scan_time();
+    }
+

    /*
      Set a max range of how many seeks we can expect when using keys
@@ -2900,7 +2921,8 @@ make_join_statistics(JOIN *join, TABLE_LIST *tables_arg, COND *conds,
    if (!s->const_keys.is_clear_all() &&                          // (1)
        (!s->table->pos_in_table_list->embedding ||               // (2)
         (s->table->pos_in_table_list->embedding &&               // (3)
-          s->table->pos_in_table_list->embedding->sj_on_expr))) // (3)
+          s->table->pos_in_table_list->embedding->sj_on_expr)) && // (3)
+        !s->table->is_filled_at_execution())
    {
      ha_rows records;
      SQL_SELECT *select;
@@ -2938,7 +2960,7 @@ make_join_statistics(JOIN *join, TABLE_LIST *tables_arg, COND *conds,
      if (records != HA_POS_ERROR)
      {
 	s->found_records=records;
-	s->read_time= (ha_rows) (s->quick ? s->quick->read_time : 0.0);
+	s->read_time= s->quick ? s->quick->read_time : 0.0;
      }
      delete select;
    }
@@ -4265,6 +4287,7 @@ 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");
@@ -4617,8 +4640,9 @@ best_access_path(JOIN      *join,
          else
            tmp= best_time;                    // Do nothing
        }
-        loose_scan_opt.check_ref_access_part2(key, start_key, records, tmp);

+        tmp += s->startup_cost;
+        loose_scan_opt.check_ref_access_part2(key, start_key, records, tmp);
      } /* not ft_key */
      if (tmp < best_time - records/(double) TIME_FOR_COMPARE)
      {
@@ -4660,13 +4684,19 @@ best_access_path(JOIN      *join,
        Since we have a 'ref' access path, and FORCE INDEX instructs us to
        choose it over ALL/index, there is no need to consider a full table
        scan.
+    (5) Non-flattenable semi-joins: don't consider doing a scan of temporary
+        table if we had an option to make lookups into it. In real-world cases,
+        lookups are cheaper than full scans, but when the table is small, they
+        can be [considered to be] more expensive, which causes lookups not to 
+        be used for cases with small datasets, which is annoying.
  */
  if ((records >= s->found_records || best > s->read_time) &&            // (1)
      !(s->quick && best_key && s->quick->index == best_key->key &&      // (2)
        best_max_key_part >= s->table->quick_key_parts[best_key->key]) &&// (2)
      !((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)
+      !(s->table->force_index && best_key && !s->quick) &&               // (4)
+      !(best_key && jtbm_subselect))                                     // (5)
  {                                             // Check full join
    ha_rows rnd_records= s->found_records;
    /*
@@ -4713,8 +4743,7 @@ best_access_path(JOIN      *join,
    }
    else
    {
-      /* Estimate cost of reading table. */
-      tmp= s->table->file->scan_time();
+      tmp= s->read_time;
      if ((s->table->map & join->outer_join) || disable_jbuf)     // Can't use join cache
      {
        /*
@@ -4743,6 +4772,7 @@ best_access_path(JOIN      *join,
      }
    }

+    tmp += s->startup_cost;
    /*
      We estimate the cost of evaluating WHERE clause for found records
      as record_count * rnd_records / TIME_FOR_COMPARE. This cost plus
@@ -6688,12 +6718,12 @@ make_join_select(JOIN *join,SQL_SELECT *select,COND *cond)
 	    the index if we are using limit and this is the first table
 	  */

-	  if ((cond &&
-               (!tab->keys.is_subset(tab->const_keys) && i > 0)) ||
+	  if (!tab->table->is_filled_at_execution() &&
+              ((cond && (!tab->keys.is_subset(tab->const_keys) && i > 0)) ||
               (!tab->const_keys.is_clear_all() && i == join->const_tables &&
                join->unit->select_limit_cnt <
                join->best_positions[i].records_read &&
-	       !(join->select_options & OPTION_FOUND_ROWS)))
+                !(join->select_options & OPTION_FOUND_ROWS))))
 	  {
 	    /* Join with outer join condition */
 	    COND *orig_cond=sel->cond;
@@ -7684,6 +7714,12 @@ void JOIN_TAB::cleanup()
      table->file->extra(HA_EXTRA_NO_KEYREAD);
    }
    table->file->ha_index_or_rnd_end();
+
+    if (table->pos_in_table_list && 
+        table->pos_in_table_list->jtbm_subselect)
+    {
+      table->pos_in_table_list->jtbm_subselect->cleanup();
+    }
    /*
      We need to reset this for next select
      (Tested in part_of_refkey)
@@ -9861,16 +9897,10 @@ static uint reset_nj_counters(JOIN *join, List<TABLE_LIST> *join_list)
    if ((nested_join= table->nested_join))
    {
      nested_join->counter= 0;
-      //nested_join->n_tables= my_count_bits(nested_join->used_tables & 
-      //                                     ~join->eliminated_tables);
      nested_join->n_tables= reset_nj_counters(join, &nested_join->join_list);
      if (!nested_join->n_tables)
        is_eliminated_nest= TRUE;
    }
-    //if (!table->table || (table->table->map & ~join->eliminated_tables))
-    //psergey-merge10^
-    //if (!table->table && (table->table->map & ~join->eliminated_tables))
-    //psergey-merge11^
    if ((!table->table && !is_eliminated_nest) || 
        (table->table && (table->table->map & ~join->eliminated_tables)))
      n++;
@@ -11396,6 +11426,8 @@ create_tmp_table(THD *thd,TMP_TABLE_PARAM *param,List<Item> &fields,
    share->keys=1;
    share->uniques= test(using_unique_constraint);
    table->key_info= table->s->key_info= keyinfo;
+    table->keys_in_use_for_query.set_bit(0);
+    share->keys_in_use.set_bit(0);
    keyinfo->key_part=key_part_info;
    keyinfo->flags=HA_NOSAME;
    keyinfo->usable_key_parts=keyinfo->key_parts= param->group_parts;
@@ -11411,6 +11443,8 @@ create_tmp_table(THD *thd,TMP_TABLE_PARAM *param,List<Item> &fields,
      bool maybe_null=(*cur_group->item)->maybe_null;
      key_part_info->null_bit=0;
      key_part_info->field=  field;
+      if (cur_group == group)
+        field->key_start.set_bit(0);
      key_part_info->offset= field->offset(table->record[0]);
      key_part_info->length= (uint16) field->key_length();
      key_part_info->type=   (uint8) field->key_type();
@@ -11481,6 +11515,8 @@ create_tmp_table(THD *thd,TMP_TABLE_PARAM *param,List<Item> &fields,
                     keyinfo->key_parts * sizeof(KEY_PART_INFO))))
      goto err;
    bzero((void*) key_part_info, keyinfo->key_parts * sizeof(KEY_PART_INFO));
+    table->keys_in_use_for_query.set_bit(0);
+    share->keys_in_use.set_bit(0);
    table->key_info= table->s->key_info= keyinfo;
    keyinfo->key_part=key_part_info;
    keyinfo->flags=HA_NOSAME | HA_NULL_ARE_EQUAL;
@@ -11519,6 +11555,13 @@ create_tmp_table(THD *thd,TMP_TABLE_PARAM *param,List<Item> &fields,
    {
      key_part_info->null_bit=0;
      key_part_info->field=    *reg_field;
+      (*reg_field)->flags |= PART_KEY_FLAG;
+      if (key_part_info == keyinfo->key_part)
+        (*reg_field)->key_start.set_bit(0);
+      key_part_info->null_bit= (*reg_field)->null_bit;
+      key_part_info->null_offset= (uint) ((*reg_field)->null_ptr -
+                                          (uchar*) table->record[0]);
+
      key_part_info->offset=   (*reg_field)->offset(table->record[0]);
      key_part_info->length=   (uint16) (*reg_field)->pack_length();
      /* TODO:
@@ -12805,6 +12848,9 @@ sub_select(JOIN *join,JOIN_TAB *join_tab,bool end_of_records)
    }
    join->thd->row_count= 0;
    
+    if (do_jtbm_materialization_if_needed(join_tab))
+      DBUG_RETURN(NESTED_LOOP_ERROR);
+
    error= (*join_tab->read_first_record)(join_tab);

    if (join_tab->keep_current_rowid)
@@ -17943,7 +17989,7 @@ static void select_describe(JOIN *join, bool need_tmp_table, bool need_order,
        /* table */
        int len= my_snprintf(table_name_buffer, 
                             sizeof(table_name_buffer)-1,
-                             "subselect%d", 
+                             "SUBQUERY#%d", 
                             tab->emb_sj_nest->sj_subq_pred->get_identifier());
 	item_list.push_back(new Item_string(table_name_buffer, len, cs));
        /* partitions */
@@ -18169,7 +18215,7 @@ static void select_describe(JOIN *join, bool need_tmp_table, bool need_order,
        if (tab->select && tab->select->quick)
          examined_rows= tab->select->quick->records;
        else if (tab->type == JT_NEXT || tab->type == JT_ALL)
-          examined_rows= tab->limit ? tab->limit : tab->table->file->records();
+          examined_rows= tab->limit ? tab->limit : tab->records;
        else
          examined_rows=(ha_rows)join->best_positions[i].records_read; 
 
@@ -18658,6 +18704,14 @@ void TABLE_LIST::print(THD *thd, table_map eliminated_tables, String *str,
    print_join(thd, eliminated_tables, str, &nested_join->join_list, query_type);
    str->append(')');
  }
+  else if (jtbm_subselect)
+  {
+    str->append(STRING_WITH_LEN(" <materialize> ("));
+    subselect_hash_sj_engine *hash_engine;
+    hash_engine= (subselect_hash_sj_engine*)jtbm_subselect->engine;
+    hash_engine->materialize_engine->print(str, query_type);
+    str->append(')');
+  }
  else
  {
    const char *cmp_name;                         // Name to compare with alias
--- a/sql/sql_select.h
+++ b/sql/sql_select.h
@@ -210,7 +210,10 @@ typedef struct st_join_table {
    method (but not 'index' for some reason), i.e. this matches method which
    E(#records) is in found_records.
  */
-  ha_rows       read_time;
+  double        read_time;
+  
+  /* Startup cost for execution */
+  double        startup_cost;

  table_map	dependent,key_dependent;
  uint		use_quick,index;
@@ -1551,6 +1554,10 @@ public:
  bool union_part; ///< this subselect is part of union 
  bool optimized; ///< flag to avoid double optimization in EXPLAIN

+  /* 
+    Subqueries that will need to be converted to semi-join nests, including
+    those converted to jtbm nests. The list is emptied when conversion is done.
+  */
  Array<Item_in_subselect> sj_subselects;
  
  /* Temporary tables used to weed-out semi-join duplicates */
--- a/sql/table.cc
+++ b/sql/table.cc
@@ -5114,6 +5114,12 @@ bool st_table::is_children_attached(void)
         (parent && parent->children_attached));
 }

+
+bool st_table::is_filled_at_execution()
+{ 
+  return test(pos_in_table_list->jtbm_subselect);
+}
+
 /*
  Cleanup this table for re-execution.

--- a/sql/table.h
+++ b/sql/table.h
@@ -914,6 +914,13 @@ struct st_table {
  inline bool needs_reopen_or_name_lock()
  { return s->version != refresh_version; }
  bool is_children_attached(void);
+ 
+  /*
+    If TRUE, the table is filled at execution phase (and so, the optimizer 
+    should not do things like range analysis or constant table detection on
+    it).
+  */
+  bool is_filled_at_execution();
 };

 enum enum_schema_table_state
@@ -1131,7 +1138,7 @@ class Item_in_subselect;
  1) table (TABLE_LIST::view == NULL)
     - base table
       (TABLE_LIST::derived == NULL)
-     - subquery - TABLE_LIST::table is a temp table
+     - FROM-clause subquery - TABLE_LIST::table is a temp table
       (TABLE_LIST::derived != NULL)
     - information schema table
       (TABLE_LIST::schema_table != NULL)
@@ -1150,6 +1157,8 @@ class Item_in_subselect;
       (TABLE_LIST::natural_join != NULL)
       - JOIN ... USING
         (TABLE_LIST::join_using_fields != NULL)
+     - semi-join nest (sj_on_expr!= NULL && sj_subq_pred!=NULL)
+  4) jtbm semi-join (jtbm_subselect != NULL)
 */

 class Index_hint;
@@ -1193,7 +1202,13 @@ struct TABLE_LIST
  table_map     sj_inner_tables;
  /* Number of IN-compared expressions */
  uint          sj_in_exprs;
+  
+  /* If this is a non-jtbm semi-join nest: corresponding subselect predicate */
  Item_in_subselect  *sj_subq_pred;
+
+  /* If this is a jtbm semi-join object: corresponding subselect predicate */
+  Item_in_subselect  *jtbm_subselect;
+
  SJ_MATERIALIZATION_INFO *sj_mat_info;

  /*