Merge MWL#90 with 5.3-main

mysql-test/r/group_by.result

@@ -1543,7 +1543,7 @@ EXPLAIN SELECT 1 FROM t1 WHERE a IN
 (SELECT a FROM t1 USE INDEX (i2) IGNORE INDEX (i2));
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 1	PRIMARY	t1	index	PRIMARY,i2	PRIMARY	4	NULL	144	Using index
-1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	144	Using where; FirstMatch(t1)
+1	PRIMARY	<subquery2>	eq_ref	distinct_key	distinct_key	4	func	1	
 CREATE TABLE t2 (a INT, b INT, KEY(a));
 INSERT INTO t2 VALUES (1, 1), (2, 2), (3,3), (4,4);
 EXPLAIN SELECT a, SUM(b) FROM t2 GROUP BY a LIMIT 2;

mysql-test/r/group_min_max.result

@@ -2401,7 +2401,7 @@ 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	Using where
 2	DEPENDENT SUBQUERY	t1	index	NULL	a	10	NULL	1	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/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/subselect.result

@@ -1361,7 +1361,7 @@ 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 where; Using index
 1	PRIMARY	t3	index	a	a	5	NULL	3	100.00	Using where; 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);
@@ -2831,7 +2831,7 @@ Note	1003	select `test`.`t1`.`one` AS `one`,`test`.`t1`.`two` AS `two`,<expr_cac
 explain extended SELECT one,two from t1 where ROW(one,two) IN (SELECT one,two FROM t2 WHERE flag = 'N');
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	filtered	Extra
 1	PRIMARY	t1	ALL	NULL	NULL	NULL	NULL	8	100.00	
-1	PRIMARY	t2	ALL	NULL	NULL	NULL	NULL	9	100.00	Using where; FirstMatch(t1)
+1	PRIMARY	<subquery2>	eq_ref	distinct_key	distinct_key	10	func,func	1	100.00	
 Warnings:
 Note	1003	select `test`.`t1`.`one` AS `one`,`test`.`t1`.`two` AS `two` from `test`.`t1` semi join (`test`.`t2`) where ((`test`.`t2`.`two` = `test`.`t1`.`two`) and (`test`.`t2`.`one` = `test`.`t1`.`one`) and (`test`.`t2`.`flag` = 'N'))
 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;
@@ -3429,7 +3429,7 @@ 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	t1	ALL	a	NULL	NULL	NULL	9	Using where
 2	DEPENDENT SUBQUERY	t1	index	NULL	a	8	NULL	1	
 DROP TABLE t1;
 create table t1( f1 int,f2 int);

mysql-test/r/subselect4.result

@@ -356,7 +356,7 @@ 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 (flat, BNL join)
 PREPARE stmt FROM "EXPLAIN SELECT EMPNAME
@@ -371,13 +371,13 @@ 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 (flat, BNL join)
 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 (flat, BNL join)
 DEALLOCATE PREPARE stmt;
@@ -394,7 +394,7 @@ 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 (flat, BNL join)
 PREPARE stmt FROM "EXPLAIN SELECT EMPNAME
@@ -409,13 +409,13 @@ 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 (flat, BNL join)
 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 (flat, BNL join)
 DEALLOCATE PREPARE stmt;
@@ -431,7 +431,7 @@ 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 (flat, BNL join)
 PREPARE stmt FROM "EXPLAIN SELECT EMPNAME
@@ -446,13 +446,13 @@ 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 (flat, BNL join)
 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 (flat, BNL join)
 DEALLOCATE PREPARE stmt;
@@ -579,7 +579,7 @@ 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 (flat, BNL join)
 PREPARE stmt FROM "EXPLAIN SELECT EMPNAME
@@ -594,13 +594,13 @@ 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 (flat, BNL join)
 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 (flat, BNL join)
 DEALLOCATE PREPARE stmt;
@@ -617,7 +617,7 @@ 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 (flat, BNL join)
 PREPARE stmt FROM "EXPLAIN SELECT EMPNAME
@@ -632,13 +632,13 @@ 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 (flat, BNL join)
 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 (flat, BNL join)
 DEALLOCATE PREPARE stmt;
@@ -654,7 +654,7 @@ 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 (flat, BNL join)
 PREPARE stmt FROM "EXPLAIN SELECT EMPNAME
@@ -669,13 +669,13 @@ 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 (flat, BNL join)
 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 (flat, BNL join)
 DEALLOCATE PREPARE stmt;

mysql-test/r/subselect_no_mat.result

@@ -1365,7 +1365,7 @@ 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 where; Using index
 1	PRIMARY	t3	index	a	a	5	NULL	3	100.00	Using where; 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_sj2.result

@@ -351,6 +351,10 @@ 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)

mysql-test/r/subselect_sj2_jcl6.result

@@ -358,6 +358,10 @@ 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)

mysql-test/r/subselect_sj_nonmerged.result

+drop table if exists t0, t1, t2, t3, t4;
+set @save_optimizer_switch=@@optimizer_switch;
+create table t0 (a int);
+insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
+create table t1 as select * from t0;
+# The following should use full scan on <subquery2> and it must scan 1 row:
+explain select * from t0 where a in (select max(a) from t1);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	<subquery2>	ALL	distinct_key	NULL	NULL	NULL	1	
+1	PRIMARY	t0	ALL	NULL	NULL	NULL	NULL	10	Using where; Using join buffer (flat, BNL join)
+2	SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	10	
+select * from t0 where a in (select max(a) from t1);
+a
+9
+insert into t1 values (11);
+select * from t0 where a in (select max(a) from t1);
+a
+delete from t1 where a=11;
+insert into t0 values (NULL);
+select * from t0 where a in (select max(a) from t1);
+a
+9
+delete from t0 where a is NULL;
+delete from t1;
+select * from t0 where a in (select max(a) from t1);
+a
+insert into t0 values (NULL);
+select * from t0 where a in (select max(a) from t1);
+a
+delete from t0 where a is NULL;
+drop table t1;
+create table t1 (a int, b int);
+insert into t1 select a,a from t0;
+create table t2 as select * from t1 where a<5;
+create table t3 as select (A.a + 10*B.a) as a from t0 A, t0 B;
+alter table t3 add primary key(a);
+# The following should have do a full scan on <subquery2> and scan 5 rows 
+#   (despite that subquery's join output estimate is 50 rows)
+explain select * from t3 where a in (select max(t2.a) from t1, t2 group by t2.b);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	<subquery2>	ALL	distinct_key	NULL	NULL	NULL	5	Using where
+1	PRIMARY	t3	eq_ref	PRIMARY	PRIMARY	8	<subquery2>.max(t2.a)	1	Using where; Using index
+2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	5	Using temporary; Using filesort
+2	SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	10	Using join buffer (flat, BNL join)
+# Compare to this which really will have 50 record combinations:
+explain select * from t3 where a in (select max(t2.a) from t1, t2 group by t2.b, t1.b);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	<subquery2>	ALL	distinct_key	NULL	NULL	NULL	50	Using where
+1	PRIMARY	t3	eq_ref	PRIMARY	PRIMARY	8	<subquery2>.max(t2.a)	1	Using where; Using index
+2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	5	Using temporary; Using filesort
+2	SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	10	Using join buffer (flat, BNL join)
+# Outer joins also work:
+explain select * from t3 
+where a in (select max(t2.a) from t1 left join t2 on t1.a=t2.a group by t2.b, t1.b);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	<subquery2>	ALL	distinct_key	NULL	NULL	NULL	50	Using where
+1	PRIMARY	t3	eq_ref	PRIMARY	PRIMARY	8	<subquery2>.max(t2.a)	1	Using where; Using index
+2	SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	10	Using temporary; Using filesort
+2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	5	Using where
+create table t4 (a int, b int, filler char(20), unique key(a,b));
+insert into t4 select A.a + 10*B.a, A.a + 10*B.a, 'filler' from t0 A, t0 B;
+explain select * from t0, t4 where 
+t4.b=t0.a and t4.a in (select max(t2.a) from t1, t2 group by t2.b);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	t0	ALL	NULL	NULL	NULL	NULL	10	
+1	PRIMARY	t4	ALL	a	NULL	NULL	NULL	100	Using where; Using join buffer (flat, BNL join)
+1	PRIMARY	<subquery2>	eq_ref	distinct_key	distinct_key	5	test.t4.a	1	
+2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	5	Using temporary; Using filesort
+2	SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	10	Using join buffer (flat, BNL join)
+insert into t4 select 100 + (B.a *100 + A.a), 100 + (B.a*100 + A.a), 'filler' from t4 A, t0 B;
+explain select * from t4 where 
+t4.a in (select max(t2.a) from t1, t2 group by t2.b) and 
+t4.b in (select max(t2.a) from t1, t2 group by t2.b);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	PRIMARY	<subquery2>	ALL	distinct_key	NULL	NULL	NULL	5	Using where
+1	PRIMARY	<subquery3>	ALL	distinct_key	NULL	NULL	NULL	5	Using where; Using join buffer (flat, BNL join)
+1	PRIMARY	t4	ref	a	a	10	<subquery2>.max(t2.a),<subquery3>.max(t2.a)	12	
+3	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	5	Using temporary; Using filesort
+3	SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	10	Using join buffer (flat, BNL join)
+2	SUBQUERY	t2	ALL	NULL	NULL	NULL	NULL	5	Using temporary; Using filesort
+2	SUBQUERY	t1	ALL	NULL	NULL	NULL	NULL	10	Using join buffer (flat, BNL join)
+drop table t1,t2,t3,t4;
+drop table t0;
+#
+# BUG#780359: Crash with get_fanout_with_deps in maria-5.3-mwl90
+#
+CREATE TABLE t1 (f1 int);
+INSERT INTO t1 VALUES (2),(2);
+CREATE TABLE t2 (f3 int);
+INSERT INTO t2 VALUES (2),(2);
+SELECT *
+FROM t1
+WHERE ( f1 ) IN (
+SELECT t2.f3
+FROM t2
+WHERE t2.f3 = 97
+AND t2.f3 = 50
+GROUP BY 1
+);
+f1
+DROP TABLE t1, t2;

mysql-test/suite/pbxt/r/group_min_max.result

@@ -2256,7 +2256,7 @@ 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	Using where
 2	DEPENDENT SUBQUERY	t1	index	NULL	a	10	NULL	1	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/subselect.result

@@ -3425,13 +3425,13 @@ id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
 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	Using where
 2	DEPENDENT SUBQUERY	t1	index	NULL	a	8	NULL	1	
 DROP TABLE t1;
 create table t1( f1 int,f2 int);

mysql-test/suite/vcol/inc/vcol_view.inc

@@ -69,10 +69,14 @@ create table t1 (a int not null,
 insert into t1 (a) values (1), (2), (3), (4);
 create view v1 as select b+1 from t1 order by 1 desc limit 2;
 select * from v1;
+--echo MariaDB-5.3: the following EXPLAIN produces incorrect #rows for table t1.
+--echo MariaDB-5.3: this is expected to go away when FROM subquery optimizations are pushed
 explain select * from v1;
 drop view v1;
 create view v1 as select c+1 from t1 order by 1 desc limit 2;
 select * from v1;
+--echo MariaDB-5.3: the following EXPLAIN produces incorrect #rows for table t1.
+--echo MariaDB-5.3: this is expected to go away when FROM subquery optimizations are pushed
 explain select * from v1;
 drop view v1;
 drop table t1;

mysql-test/suite/vcol/r/vcol_view_innodb.result

@@ -103,6 +103,8 @@ select * from v1;
 b+1
 0
 -1
+MariaDB-5.3: the following EXPLAIN produces incorrect #rows for table t1.
+MariaDB-5.3: this is expected to go away when FROM subquery optimizations are pushed
 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	
@@ -113,6 +115,8 @@ select * from v1;
 c+1
 0
 -1
+MariaDB-5.3: the following EXPLAIN produces incorrect #rows for table t1.
+MariaDB-5.3: this is expected to go away when FROM subquery optimizations are pushed
 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	

mysql-test/suite/vcol/r/vcol_view_myisam.result

@@ -103,6 +103,8 @@ select * from v1;
 b+1
 0
 -1
+MariaDB-5.3: the following EXPLAIN produces incorrect #rows for table t1.
+MariaDB-5.3: this is expected to go away when FROM subquery optimizations are pushed
 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	
@@ -113,6 +115,8 @@ select * from v1;
 c+1
 0
 -1
+MariaDB-5.3: the following EXPLAIN produces incorrect #rows for table t1.
+MariaDB-5.3: this is expected to go away when FROM subquery optimizations are pushed
 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	

mysql-test/t/subselect4.test

 # General purpose bug fix tests go here : subselect.test too large
 
+--disable_warnings
+drop table if exists t1,t2,t3,t4,t5,t6;
+--enable_warnings
 
 --echo #
 --echo # Bug #46791: Assertion failed:(table->key_read==0),function unknown
@@ -663,6 +666,7 @@ INSERT INTO t2 VALUES ('f'),('d');
 SET @old_optimizer_switch = @@session.optimizer_switch;
 SET SESSION optimizer_switch = 'materialization=on,in_to_exists=off,';
 
+select sin(0);
 EXPLAIN
 SELECT * FROM t1
 WHERE f3 = (

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);
 

mysql-test/t/subselect_sj_nonmerged.test

+#
+# Tests for non-merged semi-joins
+#
+--disable_warnings
+drop table if exists t0, t1, t2, t3, t4;
+--enable_warnings
+
+set @save_optimizer_switch=@@optimizer_switch;
+
+create table t0 (a int);
+insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
+
+
+# Check the case of subquery having agggregates but not having grouping
+
+create table t1 as select * from t0;
+--echo # The following should use full scan on <subquery2> and it must scan 1 row:
+explain select * from t0 where a in (select max(a) from t1);
+select * from t0 where a in (select max(a) from t1);
+
+# Ok, now check the trivial match/no-match/NULL on the left/NULL on the right cases
+insert into t1 values (11);
+select * from t0 where a in (select max(a) from t1);
+delete from t1 where a=11;
+
+insert into t0 values (NULL);
+select * from t0 where a in (select max(a) from t1);
+delete from t0 where a is NULL;
+
+delete from t1;
+select * from t0 where a in (select max(a) from t1);
+
+insert into t0 values (NULL);
+select * from t0 where a in (select max(a) from t1);
+delete from t0 where a is NULL;
+
+drop table t1;
+
+# 
+# Try with join subqueries
+#
+
+create table t1 (a int, b int);
+insert into t1 select a,a from t0;  # 10 rows 
+create table t2 as select * from t1 where a<5;  # 5 rows
+create table t3 as select (A.a + 10*B.a) as a from t0 A, t0 B; # 100 rows
+alter table t3 add primary key(a);
+
+--echo # The following should have do a full scan on <subquery2> and scan 5 rows 
+--echo #   (despite that subquery's join output estimate is 50 rows)
+explain select * from t3 where a in (select max(t2.a) from t1, t2 group by t2.b);
+
+--echo # Compare to this which really will have 50 record combinations:
+explain select * from t3 where a in (select max(t2.a) from t1, t2 group by t2.b, t1.b);
+
+--echo # Outer joins also work:
+explain select * from t3 
+where a in (select max(t2.a) from t1 left join t2 on t1.a=t2.a group by t2.b, t1.b);
+
+#
+# Check if joins on the outer side also work
+#
+create table t4 (a int, b int, filler char(20), unique key(a,b));
+insert into t4 select A.a + 10*B.a, A.a + 10*B.a, 'filler' from t0 A, t0 B; # 100 rows
+explain select * from t0, t4 where 
+  t4.b=t0.a and t4.a in (select max(t2.a) from t1, t2 group by t2.b);
+
+insert into t4 select 100 + (B.a *100 + A.a), 100 + (B.a*100 + A.a), 'filler' from t4 A, t0 B;
+explain select * from t4 where 
+  t4.a in (select max(t2.a) from t1, t2 group by t2.b) and 
+  t4.b in (select max(t2.a) from t1, t2 group by t2.b);
+
+drop table t1,t2,t3,t4;
+
+drop table t0;
+
+--echo #
+--echo # BUG#780359: Crash with get_fanout_with_deps in maria-5.3-mwl90
+--echo #
+CREATE TABLE t1 (f1 int);
+INSERT INTO t1 VALUES (2),(2);
+
+CREATE TABLE t2 (f3 int);
+INSERT INTO t2 VALUES (2),(2);
+
+SELECT *
+FROM t1
+WHERE ( f1 ) IN (
+        SELECT t2.f3
+        FROM t2
+        WHERE t2.f3 = 97
+        AND t2.f3 = 50
+        GROUP BY 1
+);
+
+DROP TABLE t1, t2;
+

sql-bench/test-table-elimination.sh

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

sql/item.h

@@ -1217,7 +1217,8 @@ class Item {
   virtual Item_equal *find_item_equal(COND_EQUAL *cond_equal) { return NULL; }
   /**
     Set the join tab index to the minimal (left-most) JOIN_TAB to which this
-    Item is attached.
+    Item is attached. The number is an index is depth_first_tab() traversal
+    order.
   */
   virtual void set_join_tab_idx(uint join_tab_idx_arg)
   {

sql/item_cmpfunc.cc

@@ -6004,28 +6004,12 @@ Item* Item_equal::get_first(Item *field_item)
   {
     /*
       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= field_tab;
-    JOIN *join= field_tab->join;
-    int tab_idx= field_tab - field_tab->join->join_tab;
 
-    DBUG_ASSERT(join->join_tab[tab_idx].table->map &
-                emb_nest->sj_inner_tables);
-
-    /* Find the first table of this semi-join nest */
-    for (int i= tab_idx-1; 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 (it.get_curr_field()->table->reginfo.join_tab >= first)
+      if (it.get_curr_field()->table->pos_in_table_list->embedding == emb_nest)
       {
         /*
           If we found given field then return NULL to avoid unnecessary
@@ -6037,33 +6021,28 @@ Item* Item_equal::get_first(Item *field_item)
   }
   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++))
-    {
-      Item_field *fld_item= (Item_field *) (item->real_item());
-      TABLE_LIST *emb_nest= fld_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 equal_items.head();
   }
   // Shouldn't get here.

sql/opt_range.cc

@@ -341,8 +341,9 @@ class SEL_ARG :public Sql_alloc
   SEL_ARG(Field *field, uint8 part, uchar *min_value, uchar *max_value,
 	  uint8 min_flag, uint8 max_flag, uint8 maybe_flag);
   SEL_ARG(enum Type type_arg)
-    :min_flag(0),elements(1),use_count(1),left(0),right(0),next_key_part(0),
-    color(BLACK), type(type_arg)
+    :min_flag(0), max_part_no(0) /* first key part means 1. 0 mean 'no parts'*/, 
+     elements(1),use_count(1),left(0),right(0),
+     next_key_part(0), color(BLACK), type(type_arg)
   {}
   inline bool is_same(SEL_ARG *arg)
   {
@@ -2909,7 +2910,8 @@ 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)
@@ -4319,7 +4321,7 @@ double get_sweep_read_cost(const PARAM *param, ha_rows records)
       return 1;
     */
     JOIN *join= param->thd->lex->select_lex.join;
-    if (!join || join->tables == 1)
+    if (!join || join->table_count == 1)
     {
       /* No join, assume reading is done in one 'sweep' */
       result= busy_blocks*(DISK_SEEK_BASE_COST +
@@ -11270,7 +11272,7 @@ get_best_group_min_max(PARAM *param, SEL_TREE *tree)
   /* Perform few 'cheap' tests whether this access method is applicable. */
   if (!join)
     DBUG_RETURN(NULL);        /* This is not a select statement. */
-  if ((join->tables != 1) ||  /* The query must reference one table. */
+  if ((join->table_count != 1) ||  /* The query must reference one table. */
       ((!join->group_list) && /* Neither GROUP BY nor a DISTINCT query. */
        (!join->select_distinct)) ||
       (join->select_lex->olap == ROLLUP_TYPE)) /* Check (B3) for ROLLUP */

sql/opt_subselect.h

-/* */
+/*
+  Semi-join subquery optimization code definitions
+*/
 
 #ifdef USE_PRAGMA_INTERFACE
 #pragma interface			/* gcc class implementation */
@@ -366,4 +368,10 @@ 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

@@ -7797,6 +7797,18 @@ 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); /* psergey-todo: WHY ER_TOO_MANY_TABLES ???*/
+        DBUG_RETURN(1);
+      }
+      DBUG_ASSERT(item == table_list->jtbm_subselect);
+      if (table_list->jtbm_subselect->setup_mat_engine()) // dont_switch_arena=FALSE 
+        DBUG_RETURN(1);
+    }
   }
 
   /* Precompute and store the row types of NATURAL/USING joins. */
@@ -8218,7 +8230,7 @@ int setup_conds(THD *thd, TABLE_LIST *tables, TABLE_LIST *leaves,
       goto err_no_arena;
   }
 
-  thd->thd_marker.emb_on_expr_nest= (TABLE_LIST*)1;
+  thd->thd_marker.emb_on_expr_nest= NO_JOIN_NEST;
   if (*conds)
   {
     thd->where="where clause";

sql/sql_cursor.cc

@@ -363,7 +363,6 @@ Sensitive_cursor::open(JOIN *join_arg)
   join= join_arg;
   THD *thd= join->thd;
   /* First non-constant table */
-  JOIN_TAB *join_tab= join->join_tab + join->const_tables;
   DBUG_ENTER("Sensitive_cursor::open");
 
   join->change_result(result);
@@ -381,26 +380,29 @@ Sensitive_cursor::open(JOIN *join_arg)
 
   /* Prepare JOIN for reading rows. */
   join->tmp_table= 0;
-  join->join_tab[join->tables-1].next_select= setup_end_select_func(join);
+  join->join_tab[join->top_join_tab_count - 1].next_select= setup_end_select_func(join);
   join->send_records= 0;
   join->fetch_limit= join->unit->offset_limit_cnt;
 
   /* Disable JOIN CACHE as it is not working with cursors yet */
-  for (JOIN_TAB *tab= join_tab;
-       tab != join->join_tab + join->tables - 1;
-       tab++)
+  for (JOIN_TAB *tab= first_linear_tab(join, WITHOUT_CONST_TABLES); 
+       tab != join->join_tab + join->top_join_tab_count - 1;
+       tab= next_linear_tab(join, tab, WITH_BUSH_ROOTS))
   {
     if (tab->next_select == sub_select_cache)
       tab->next_select= sub_select;
   }
 
-  DBUG_ASSERT(join_tab->table->reginfo.not_exists_optimize == 0);
-  DBUG_ASSERT(join_tab->not_used_in_distinct == 0);
+#ifndef DBUG_OFF
+  JOIN_TAB *first_tab= first_linear_tab(join, WITHOUT_CONST_TABLES);
+  DBUG_ASSERT(first_tab->table->reginfo.not_exists_optimize == 0);
+  DBUG_ASSERT(first_tab->not_used_in_distinct == 0);
   /*
     null_row is set only if row not found and it's outer join: should never
     happen for the first table in join_tab list
   */
-  DBUG_ASSERT(join_tab->table->null_row == 0);
+  DBUG_ASSERT(first_tab->table->null_row == 0);
+#endif
   DBUG_RETURN(0);
 }
 

sql/sql_delete.cc

@@ -681,9 +681,10 @@ multi_delete::initialize_tables(JOIN *join)
 
 
   walk= delete_tables;
-  for (JOIN_TAB *tab=join->join_tab, *end=join->join_tab+join->tables;
-       tab < end;
-       tab++)
+
+  for (JOIN_TAB *tab= first_linear_tab(join, WITH_CONST_TABLES); 
+       tab; 
+       tab= next_linear_tab(join, tab, WITH_BUSH_ROOTS))
   {
     if (tab->table->map & tables_to_delete_from)
     {

sql/sql_join_cache.h

@@ -121,11 +121,14 @@ class JOIN_CACHE :public Sql_alloc
   */   
   JOIN *join;  
 
-  /* 
-    Cardinality of the range of join tables whose fields can be put into the
-    cache. A table from the range not necessarily contributes to the cache.
+  /*
+    JOIN_TAB of the first table that can have it's fields in the join cache. 
+    That is, tables in the [start_tab, tab) range can have their fields in the
+    join cache. 
+    If a join tab in the range represents an SJM-nest, then all tables from the
+    nest can have their fields in the join cache, too.
   */
-  uint tables;
+  JOIN_TAB *start_tab;
 
   /* 
     The total number of flag and data fields that can appear in a record
@@ -647,8 +650,6 @@ class JOIN_CACHE :public Sql_alloc
     buff= 0;
   }   
   
-  JOIN_TAB *get_next_table(JOIN_TAB *tab);
-  
   friend class JOIN_CACHE_HASHED;
   friend class JOIN_CACHE_BNL;
   friend class JOIN_CACHE_BKA;

sql/sql_lex.cc

@@ -3121,8 +3121,16 @@ bool st_select_lex::optimize_unflattened_subqueries()
   for (SELECT_LEX_UNIT *un= first_inner_unit(); un; un= un->next_unit())
   {
     Item_subselect *subquery_predicate= un->item;
+    
     if (subquery_predicate)
     {
+      if (subquery_predicate->substype() == Item_subselect::IN_SUBS)
+      {
+        Item_in_subselect *in_subs=(Item_in_subselect*)subquery_predicate;
+        if (in_subs->is_jtbm_merged)
+          continue;
+      }
+
       for (SELECT_LEX *sl= un->first_select(); sl; sl= sl->next_select())
       {
         JOIN *inner_join= sl->join;