MWL#90: Subqueries: Inside-out execution for materialized non-sj subqueries

- Merge with MariaDB 5.3 -main

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;

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	<subquery2>	ALL	distinct_key	NULL	NULL	NULL	8	
+1	PRIMARY	t1_outer	ref	a	a	5	<subquery2>.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);

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;

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;

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;

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

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

mysql-test/r/partition_range.result

@@ -73,13 +73,13 @@ 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
@@ -112,16 +112,16 @@ 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

mysql-test/r/subselect.result

@@ -1360,7 +1360,7 @@ explain extended select * from t2 where t2.a in (select t1.a from t1,t3 where t1
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	t2	index	a	a	5	NULL	4	100.00	Using index
 1	PRIMARY	t3	index	a	a	5	NULL	3	100.00	Using index
-1	PRIMARY	t1	ref	a	a	10	test.t2.a,test.t3.a	116	100.61	Using index; FirstMatch(t2)
+1	PRIMARY	t1	ref	a	a	10	test.t2.a,test.t3.a	116	100.00	Using index; FirstMatch(t2)
 Warnings:
 Note	1003	select `test`.`t2`.`a` AS `a` from `test`.`t2` semi join (`test`.`t1` join `test`.`t3`) where ((`test`.`t1`.`a` = `test`.`t2`.`a`) and (`test`.`t1`.`b` = `test`.`t3`.`a`))
 insert into t1 values (3,31);
@@ -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	<subquery2>	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	<subquery2>	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	<subquery2>	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 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 from `test`.`t1` group by `test`.`t1`.`a`) join `test`.`t1` where (`<subquery2>`.`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	<subquery2>	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 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 from `test`.`t1` where (`test`.`t1`.`a` > 3) group by `test`.`t1`.`a`) join `test`.`t1` where (`<subquery2>`.`1` = 1)
 DROP TABLE t1;
 #
 # Bug#45061: Incorrectly market field caused wrong result.

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	<subquery2>	ALL	distinct_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	<subquery3>	eq_ref	distinct_key	distinct_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	<subquery2>	ALL	distinct_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	<subquery2>	ALL	distinct_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	<subquery2>	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	<subquery2>	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	<subquery2>	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	<subquery2>	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	<subquery2>	ALL	distinct_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	<subquery2>	ALL	distinct_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	<subquery2>	eq_ref	distinct_key	distinct_key	10	func,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	<subquery2>	eq_ref	distinct_key	distinct_key	10	func,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	<subquery2>	eq_ref	distinct_key	distinct_key	15	func,func,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	<subquery2>	ALL	distinct_key	NULL	NULL	NULL	2	100.00	
 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	

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	<subquery2>	ALL	distinct_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
@@ -1030,7 +1030,6 @@ 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;
 a	b	c
 256	67	NULL
-256	67	NULL
 drop table t1, t11, t12, t21, t22;
 create table t1(a int);
 insert into t1 values (0),(1);
@@ -1040,7 +1039,7 @@ 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	<subquery3>	eq_ref	distinct_key	distinct_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 +1162,7 @@ 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	<subquery2>	ALL	distinct_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 +1211,33 @@ 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	<subquery2>	ALL	distinct_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	<subquery2>	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	<subquery2>	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	<subquery2>	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	<subquery2>	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 +1245,14 @@ 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	<subquery2>	ALL	distinct_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	<subquery2>	ALL	distinct_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 +1278,14 @@ 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	<subquery2>	eq_ref	distinct_key	distinct_key	10	func,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	<subquery2>	eq_ref	distinct_key	distinct_key	10	func,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 +1324,7 @@ 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	<subquery2>	eq_ref	distinct_key	distinct_key	15	func,func,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 +1397,7 @@ 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	<subquery2>	ALL	distinct_key	NULL	NULL	NULL	2	100.00	
 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

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	<subquery2>	eq_ref	distinct_key	distinct_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	<subquery2>	eq_ref	distinct_key	distinct_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	<subquery2>	eq_ref	distinct_key	distinct_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	<subquery2>	eq_ref	distinct_key	distinct_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	<subquery2>	eq_ref	distinct_key	distinct_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	<subquery2>	eq_ref	distinct_key	distinct_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	<subquery2>	eq_ref	distinct_key	distinct_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	<subquery2>	eq_ref	distinct_key	distinct_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	<subquery2>	eq_ref	distinct_key	distinct_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;

mysql-test/r/subselect_no_mat.result

@@ -1364,7 +1364,7 @@ explain extended select * from t2 where t2.a in (select t1.a from t1,t3 where t1
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	t2	index	a	a	5	NULL	4	100.00	Using index
 1	PRIMARY	t3	index	a	a	5	NULL	3	100.00	Using index
-1	PRIMARY	t1	ref	a	a	10	test.t2.a,test.t3.a	116	100.61	Using index; FirstMatch(t2)
+1	PRIMARY	t1	ref	a	a	10	test.t2.a,test.t3.a	116	100.00	Using index; FirstMatch(t2)
 Warnings:
 Note	1003	select `test`.`t2`.`a` AS `a` from `test`.`t2` semi join (`test`.`t1` join `test`.`t3`) where ((`test`.`t1`.`a` = `test`.`t2`.`a`) and (`test`.`t1`.`b` = `test`.`t3`.`a`))
 insert into t1 values (3,31);

mysql-test/r/subselect_no_semijoin.result

@@ -1302,7 +1302,7 @@ 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
 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` 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 `test`.`t2` where <in_optimizer>(`test`.`t2`.`a`,`test`.`t2`.`a` in ( <materialize> (select `test`.`t1`.`a` from `test`.`t1` ), <primary_index_lookup>(`test`.`t2`.`a` in <temporary table> on distinct_key where ((`test`.`t2`.`a` = `<subquery2>`.`a`)))))
 select * from t2 where t2.a in (select a from t1 where t1.b <> 30);
 a
 2
@@ -1312,7 +1312,7 @@ 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
 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` 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 `test`.`t2` where <in_optimizer>(`test`.`t2`.`a`,`test`.`t2`.`a` in ( <materialize> (select `test`.`t1`.`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` = `<subquery2>`.`a`)))))
 select * from t2 where t2.a in (select t1.a from t1,t3 where t1.b=t3.a);
 a
 2
@@ -1323,7 +1323,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 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` 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 `test`.`t2` where <in_optimizer>(`test`.`t2`.`a`,`test`.`t2`.`a` in ( <materialize> (select `test`.`t1`.`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` = `<subquery2>`.`a`)))))
 drop table t1, t2, t3;
 create table t1 (a int, b int, index a (a,b));
 create table t2 (a int, index a (a));
@@ -1345,7 +1345,7 @@ 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
 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` 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 `test`.`t2` where <in_optimizer>(`test`.`t2`.`a`,`test`.`t2`.`a` in ( <materialize> (select `test`.`t1`.`a` from `test`.`t1` ), <primary_index_lookup>(`test`.`t2`.`a` in <temporary table> on distinct_key where ((`test`.`t2`.`a` = `<subquery2>`.`a`)))))
 select * from t2 where t2.a in (select a from t1 where t1.b <> 30);
 a
 2
@@ -1355,7 +1355,7 @@ 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
 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` 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 `test`.`t2` where <in_optimizer>(`test`.`t2`.`a`,`test`.`t2`.`a` in ( <materialize> (select `test`.`t1`.`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` = `<subquery2>`.`a`)))))
 select * from t2 where t2.a in (select t1.a from t1,t3 where t1.b=t3.a);
 a
 2
@@ -1366,7 +1366,7 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 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` 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 `test`.`t2` where <in_optimizer>(`test`.`t2`.`a`,`test`.`t2`.`a` in ( <materialize> (select `test`.`t1`.`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` = `<subquery2>`.`a`)))))
 insert into t1 values (3,31);
 select * from t2 where t2.a in (select a from t1 where t1.b <> 30);
 a
@@ -1382,7 +1382,7 @@ 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
 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` 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 `test`.`t2` where <in_optimizer>(`test`.`t2`.`a`,`test`.`t2`.`a` in ( <materialize> (select `test`.`t1`.`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` = `<subquery2>`.`a`)))))
 drop table t0, t1, t2, t3;
 create table t1 (a int, b int);
 create table t2 (a int, b int);
@@ -2836,7 +2836,7 @@ 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
 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`,`test`.`t2`.`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 `test`.`t1` where <in_optimizer>((`test`.`t1`.`one`,`test`.`t1`.`two`),(`test`.`t1`.`one`,`test`.`t1`.`two`) in ( <materialize> (select `test`.`t2`.`one`,`test`.`t2`.`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` = `<subquery2>`.`one`) and (`test`.`t1`.`two` = `<subquery2>`.`two`)))))
 explain extended SELECT one,two,ROW(one,two) IN (SELECT one,two FROM t2 WHERE flag = '0' group by one,two) as 'test' from t1;
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	8	100.00	
@@ -4329,13 +4329,13 @@ 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
 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 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 `test`.`t1` where <in_optimizer>(1,1 in ( <materialize> (select 1 from `test`.`t1` group by `test`.`t1`.`a` ), <primary_index_lookup>(1 in <temporary table> on distinct_key where ((1 = `<subquery2>`.`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
 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 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 `test`.`t1` where <in_optimizer>(1,1 in ( <materialize> (select 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 = `<subquery2>`.`1`)))))
 DROP TABLE t1;
 #
 # Bug#45061: Incorrectly market field caused wrong result.

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	<subquery2>	eq_ref	distinct_key	distinct_key	13	func,func	1	100.00	
 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	<subquery2>	eq_ref	distinct_key	distinct_key	8	func,func	1	100.00	
 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`))

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	<subquery2>	ALL	distinct_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	<subquery2>	ALL	distinct_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	<subquery2>	eq_ref	distinct_key	distinct_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	<subquery2>	ALL	distinct_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	<subquery2>	eq_ref	distinct_key	distinct_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	<subquery2>	ALL	distinct_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	<subquery2>	eq_ref	distinct_key	distinct_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	<subquery2>	eq_ref	distinct_key	distinct_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	<subquery2>	eq_ref	distinct_key	distinct_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)

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	<subquery2>	ALL	distinct_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	<subquery2>	ALL	distinct_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	<subquery2>	eq_ref	distinct_key	distinct_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	<subquery2>	ALL	distinct_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	<subquery2>	eq_ref	distinct_key	distinct_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	<subquery2>	ALL	distinct_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	<subquery2>	eq_ref	distinct_key	distinct_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	<subquery2>	eq_ref	distinct_key	distinct_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	<subquery2>	eq_ref	distinct_key	distinct_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)

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	<subquery2>	eq_ref	distinct_key	distinct_key	13	func,func	1	100.00	
 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	<subquery2>	eq_ref	distinct_key	distinct_key	8	func,func	1	100.00	
 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`))

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);

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

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

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	<subquery2>	ALL	distinct_key	NULL	NULL	NULL	15	
+1	PRIMARY	t1_outer	ref	a	a	5	<subquery2>.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);

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;

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

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,

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	<subquery2>	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	<subquery2>	ALL	distinct_key	NULL	NULL	NULL	9	
+1	PRIMARY	t1	ref	a	a	8	<subquery2>.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);

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);
 

sql-bench/test-table-elimination.sh

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

sql/item_cmpfunc.cc

@@ -5740,25 +5740,11 @@ Item_field* Item_equal::get_first(Item_field *field)
   {
     /*
       It's a field from an materialized semi-join. We can substitute it only
-      for a field from the same semi-join.
+      for a field from the same semi-join. Find the first of such items.
     */
-    JOIN_TAB *first;
-    JOIN *join= field_tab->join;
-    int tab_idx= field_tab - field_tab->join->join_tab;
-
-    /* Find the first table of this semi-join nest */
-    for (int i= tab_idx; i >= (int)join->const_tables; i--)
-    {
-      if (join->join_tab[i].table->map & emb_nest->sj_inner_tables)
-        first= join->join_tab + i;
-      else
-        // Found first tab that doesn't belong to current SJ.
-        break;
-    }
-    /* Find an item to substitute for. */
     while ((item= it++))
     {
-      if (item->field->table->reginfo.join_tab >= first)
+      if (item->field->table->pos_in_table_list->embedding == emb_nest)
       {
         /*
           If we found given field then return NULL to avoid unnecessary
@@ -5770,32 +5756,27 @@ Item_field* Item_equal::get_first(Item_field *field)
   }
   else
   {
-#if 0    
     /*
       The field is not in SJ-Materialization nest. We must return the first
-      field that's not embedded in a SJ-Materialization nest.
-      Example: suppose we have a join order:
+      field in the join order. The field may be inside a semi-join nest, i.e 
+      a join order may look like this:
 
           SJ-Mat(it1  it2)  ot1  ot2
 
-      and equality ot2.col = ot1.col = it2.col
-      If we're looking for best substitute for 'ot2.col', we should pick ot1.col
-      and not it2.col, because when we run a join between ot1 and ot2
-      execution of SJ-Mat(...) has already finished and we can't rely on the
-      value of it*.*.
-      psergey-fix-fix: ^^ THAT IS INCORRECT ^^. Pick the first, whatever that
-      is.
+      where we're looking what to substitute ot2.col for. In this case we must 
+      still return it1.col, here's a proof why:
+
+      First let's note that either it1.col or it2.col participates in 
+      subquery's IN-equality. It can't be otherwise, because materialization is
+      only applicable to uncorrelated subqueries, so the only way we could
+      infer "it1.col=ot1.col" is from the IN-equality. Ok, so IN-eqality has 
+      it1.col or it2.col on its inner side. it1.col is first such item in the
+      join order, so it's not possible for SJ-Mat to be
+      SJ-Materialization-lookup, it is SJ-Materialization-Scan. The scan part
+      of this strategy will unpack value of it1.col=it2.col into it1.col
+      (that's the first equal item inside the subquery), and we'll be able to
+      get it from there. qed.
     */
-    while ((item= it++))
-    {
-      TABLE_LIST *emb_nest= item->field->table->pos_in_table_list->embedding;
-      if (!emb_nest || !emb_nest->sj_mat_info || 
-          !emb_nest->sj_mat_info->is_used)
-      {
-        return item;
-      }
-    }
-#endif
     return fields.head();
   }
   // Shouldn't get here.

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;
@@ -334,7 +336,9 @@ protected:
     all JOIN in UNION
   */
   Item *expr;
+public:
   Item_in_optimizer *optimizer;
+protected:
   bool was_null;
   bool abort_on_null;
 public:
@@ -380,6 +384,16 @@ public:
   };
   enum_exec_method exec_method;
 
+  /*
+    TRUE<=>this is a flattenable semi-join, false overwise.
+  */
+  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;
@@ -429,7 +443,7 @@ 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; }
@@ -503,6 +517,7 @@ 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
 
@@ -735,7 +750,7 @@ 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. */
@@ -747,14 +762,16 @@ 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. */
@@ -767,7 +784,9 @@ 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,
@@ -803,10 +822,11 @@ 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()

sql/opt_range.cc

@@ -2287,7 +2287,8 @@ 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)

sql/opt_subselect.h

-/* */
+/*
+  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);
+
+enum_nested_loop_state join_tab_execution_startup(JOIN_TAB *tab);
 

sql/sql_base.cc

@@ -7682,6 +7682,17 @@ 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. */

sql/table.cc

@@ -5148,6 +5148,12 @@ 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.