Note 1003 select `test`.`t2`.`a` AS `a`,0 AS `a`,0 AS `b` from `test`.`t1` left join `test`.`t2` on((0 <> 0)) where <expr_cache><0>(<in_optimizer>(0,<exists>(select 0 from `test`.`t1` where (<cache>(0) = 0))))
Note 1003 select `test`.`t2`.`a` AS `a`,0 AS `a`,0 AS `b` from `test`.`t1` semi join (`test`.`t1`) left join `test`.`t2` on((0 <> 0)) where 1
SELECT * FROM t2 RIGHT JOIN v1 AS t ON t.a != 0
WHERE t.a IN (SELECT b FROM t1);
a a b
...
...
@@ -1002,10 +1002,10 @@ SELECT * FROM t2 RIGHT JOIN v1 AS t ON t.a != 0
WHERE t.a IN (SELECT b FROM t1);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 system NULL NULL NULL NULL 1 100.00
1 PRIMARY t1 system NULL NULL NULL NULL 1 100.00
1 PRIMARY t2 ALL NULL NULL NULL NULL 2 100.00 Using where
Note 1003 select `test`.`t2`.`a` AS `a`,0 AS `a`,0 AS `b` from `test`.`t1` left join `test`.`t2` on((0 <> 0)) where <expr_cache><0>(<in_optimizer>(0,<exists>(select 0 from `test`.`t1` where (<cache>(0) = 0))))
Note 1003 select `test`.`t2`.`a` AS `a`,0 AS `a`,0 AS `b` from `test`.`t1` semi join (`test`.`t1`) left join `test`.`t2` on((0 <> 0)) where 1
DROP VIEW v1;
DROP TABLE t1,t2;
#
...
...
@@ -1147,7 +1147,7 @@ EXPLAIN
SELECT a FROM t1 WHERE (a,b) IN (SELECT * FROM v1);
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 2 Using where
2 DEPENDENT SUBQUERY <derived3> index_subquery key0 key0 10 func,func 2 Using where
set @subselect_extra_no_sj_tmp=@@optimizer_switch;
set optimizer_switch='semijoin=on,firstmatch=on,loosescan=on';
drop table if exists t1,t2,t3,t4;
drop view if exists v1,v2,v3;
# From explain.test:
#
# Bug#37870: Usage of uninitialized value caused failed assertion.
#
create table t1 (dt datetime not null, t time not null);
create table t2 (dt datetime not null);
insert into t1 values ('2001-01-01 1:1:1', '1:1:1'),
('2001-01-01 1:1:1', '1:1:1');
insert into t2 values ('2001-01-01 1:1:1'), ('2001-01-01 1:1:1');
flush tables;
EXPLAIN SELECT OUTR.dt FROM t1 AS OUTR WHERE OUTR.dt IN (SELECT INNR.dt FROM t2 AS INNR WHERE OUTR.dt IS NULL );
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY OUTR ALL NULL NULL NULL NULL 2 Using where; Start temporary
1 PRIMARY INNR ALL NULL NULL NULL NULL 2 Using where; End temporary; Using join buffer (flat, BNL join)
flush tables;
SELECT OUTR.dt FROM t1 AS OUTR WHERE OUTR.dt IN (SELECT INNR.dt FROM t2 AS INNR WHERE OUTR.dt IS NULL );
dt
flush tables;
EXPLAIN SELECT OUTR.dt FROM t1 AS OUTR WHERE OUTR.dt IN ( SELECT INNR.dt FROM t2 AS INNR WHERE OUTR.t < '2005-11-13 7:41:31' );
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY OUTR ALL NULL NULL NULL NULL 2 Using where; Start temporary
1 PRIMARY INNR ALL NULL NULL NULL NULL 2 Using where; End temporary; Using join buffer (flat, BNL join)
flush tables;
SELECT OUTR.dt FROM t1 AS OUTR WHERE OUTR.dt IN ( SELECT INNR.dt FROM t2 AS INNR WHERE OUTR.t < '2005-11-13 7:41:31' );
dt
2001-01-01 01:01:01
2001-01-01 01:01:01
drop tables t1, t2;
# From type_datetime.test:
#
# Bug #32694: NOT NULL table field in a subquery produces invalid results
#
create table t1 (id int(10) not null, cur_date datetime not null);
create table t2 (id int(10) not null, cur_date date not null);
insert into t1 (id, cur_date) values (1, '2007-04-25 18:30:22');
insert into t2 (id, cur_date) values (1, '2007-04-25');
explain extended
select * from t1
where id in (select id from t1 as x1 where (t1.cur_date is null));
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 noticed after reading const tables
Warnings:
Note 1276 Field or reference 'test.t1.cur_date' of SELECT #2 was resolved in SELECT #1
Note 1003 select 1 AS `id`,'2007-04-25 18:30:22' AS `cur_date` from `test`.`t1` semi join (`test`.`t1` `x1`) where (('2007-04-25 18:30:22' = 0))
select * from t1
where id in (select id from t1 as x1 where (t1.cur_date is null));
id cur_date
explain extended
select * from t2
where id in (select id from t2 as x1 where (t2.cur_date is null));
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 noticed after reading const tables
Warnings:
Note 1276 Field or reference 'test.t2.cur_date' of SELECT #2 was resolved in SELECT #1
Note 1003 select 1 AS `id`,'2007-04-25' AS `cur_date` from `test`.`t2` semi join (`test`.`t2` `x1`) where (('2007-04-25' = 0))
select * from t2
where id in (select id from t2 as x1 where (t2.cur_date is null));
id cur_date
insert into t1 (id, cur_date) values (2, '2007-04-26 18:30:22');
insert into t2 (id, cur_date) values (2, '2007-04-26');
explain extended
select * from t1
where id in (select id from t1 as x1 where (t1.cur_date is null));
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; Start temporary
1 PRIMARY x1 ALL NULL NULL NULL NULL 2 100.00 Using where; End temporary; Using join buffer (flat, BNL join)
Warnings:
Note 1276 Field or reference 'test.t1.cur_date' of SELECT #2 was resolved in SELECT #1
Note 1003 select `test`.`t1`.`id` AS `id`,`test`.`t1`.`cur_date` AS `cur_date` from `test`.`t1` semi join (`test`.`t1` `x1`) where ((`test`.`x1`.`id` = `test`.`t1`.`id`) and (`test`.`t1`.`cur_date` = 0))
select * from t1
where id in (select id from t1 as x1 where (t1.cur_date is null));
id cur_date
explain extended
select * from t2
where id in (select id from t2 as x1 where (t2.cur_date is null));
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t2 ALL NULL NULL NULL NULL 2 100.00 Using where; Start temporary
1 PRIMARY x1 ALL NULL NULL NULL NULL 2 100.00 Using where; End temporary; Using join buffer (flat, BNL join)
Warnings:
Note 1276 Field or reference 'test.t2.cur_date' of SELECT #2 was resolved in SELECT #1
Note 1003 select `test`.`t2`.`id` AS `id`,`test`.`t2`.`cur_date` AS `cur_date` from `test`.`t2` semi join (`test`.`t2` `x1`) where ((`test`.`x1`.`id` = `test`.`t2`.`id`) and (`test`.`t2`.`cur_date` = 0))
select * from t2
where id in (select id from t2 as x1 where (t2.cur_date is null));
id cur_date
drop table t1,t2;
#
# From group_min_max.test
#
create table t1 (
a1 char(64), a2 char(64), b char(16), c char(16) not null, d char(16), dummy char(64) default ' '
1 PRIMARY NULL NULL NULL NULL NULL NULL NULL NULL Impossible WHERE noticed after reading const tables
Warnings:
Note 1276 Field or reference 'test.t1.cur_date' of SELECT #2 was resolved in SELECT #1
Note 1003 select 1 AS `id`,'2007-04-25 18:30:22' AS `cur_date` from `test`.`t1` where <expr_cache><1>(<in_optimizer>(1,<exists>(select `test`.`x1`.`id` from `test`.`t1` `x1` where 0)))
Note 1003 select 1 AS `id`,'2007-04-25 18:30:22' AS `cur_date` from `test`.`t1` semi join (`test`.`t1` `x1`) where (('2007-04-25 18:30:22' = 0))
select * from t1
where id in (select id from t1 as x1 where (t1.cur_date is null));
id cur_date
...
...
@@ -526,11 +525,10 @@ explain extended
select * from t2
where id in (select id from t2 as x1 where (t2.cur_date is null));
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 noticed after reading const tables
Warnings:
Note 1276 Field or reference 'test.t2.cur_date' of SELECT #2 was resolved in SELECT #1
Note 1003 select 1 AS `id`,'2007-04-25' AS `cur_date` from `test`.`t2` where <expr_cache><1>(<in_optimizer>(1,<exists>(select `test`.`x1`.`id` from `test`.`t2` `x1` where 0)))
Note 1003 select 1 AS `id`,'2007-04-25' AS `cur_date` from `test`.`t2` semi join (`test`.`t2` `x1`) where (('2007-04-25' = 0))
select * from t2
where id in (select id from t2 as x1 where (t2.cur_date is null));
id cur_date
...
...
@@ -540,11 +538,11 @@ explain extended
select * from t1
where id in (select id from t1 as x1 where (t1.cur_date is null));
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 DEPENDENT SUBQUERY x1 ALL NULL NULL NULL NULL 2 100.00 Using where
1 PRIMARY t1 ALL NULL NULL NULL NULL 2 100.00 Using where; Start temporary
1 PRIMARY x1 ALL NULL NULL NULL NULL 2 100.00 Using where; End temporary; Using join buffer (flat, BNL join)
Warnings:
Note 1276 Field or reference 'test.t1.cur_date' of SELECT #2 was resolved in SELECT #1
Note 1003 select `test`.`t1`.`id` AS `id`,`test`.`t1`.`cur_date` AS `cur_date` from `test`.`t1` where <expr_cache><`test`.`t1`.`id`,`test`.`t1`.`cur_date`>(<in_optimizer>(`test`.`t1`.`id`,<exists>(select `test`.`x1`.`id` from `test`.`t1` `x1` where ((`test`.`t1`.`cur_date` = 0) and (<cache>(`test`.`t1`.`id`) = `test`.`x1`.`id`)))))
Note 1003 select `test`.`t1`.`id` AS `id`,`test`.`t1`.`cur_date` AS `cur_date` from `test`.`t1` semi join (`test`.`t1` `x1`) where ((`test`.`x1`.`id` = `test`.`t1`.`id`) and (`test`.`t1`.`cur_date` = 0))
select * from t1
where id in (select id from t1 as x1 where (t1.cur_date is null));
id cur_date
...
...
@@ -552,11 +550,11 @@ explain extended
select * from t2
where id in (select id from t2 as x1 where (t2.cur_date is null));
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t2 ALL NULL NULL NULL NULL 2 100.00 Using where
2 DEPENDENT SUBQUERY x1 ALL NULL NULL NULL NULL 2 100.00 Using where
1 PRIMARY t2 ALL NULL NULL NULL NULL 2 100.00 Using where; Start temporary
1 PRIMARY x1 ALL NULL NULL NULL NULL 2 100.00 Using where; End temporary; Using join buffer (flat, BNL join)
Warnings:
Note 1276 Field or reference 'test.t2.cur_date' of SELECT #2 was resolved in SELECT #1
Note 1003 select `test`.`t2`.`id` AS `id`,`test`.`t2`.`cur_date` AS `cur_date` from `test`.`t2` where <expr_cache><`test`.`t2`.`id`,`test`.`t2`.`cur_date`>(<in_optimizer>(`test`.`t2`.`id`,<exists>(select `test`.`x1`.`id` from `test`.`t2` `x1` where ((`test`.`t2`.`cur_date` = 0) and (<cache>(`test`.`t2`.`id`) = `test`.`x1`.`id`)))))
Note 1003 select `test`.`t2`.`id` AS `id`,`test`.`t2`.`cur_date` AS `cur_date` from `test`.`t2` semi join (`test`.`t2` `x1`) where ((`test`.`x1`.`id` = `test`.`t2`.`id`) and (`test`.`t2`.`cur_date` = 0))
select * from t2
where id in (select id from t2 as x1 where (t2.cur_date is null));
explain extended select * from t2 where t2.a in (select a from t1);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t2 index NULL PRIMARY 4 NULL 4 100.00 Using where; Using index
2 DEPENDENT SUBQUERY t1 unique_subquery PRIMARY PRIMARY 4 func 1 100.00 Using index
1 PRIMARY t2 index PRIMARY PRIMARY 4 NULL 4 100.00 Using index
1 PRIMARY t1 index PRIMARY PRIMARY 4 NULL 4 75.00 Using where; Using index; Using join buffer (flat, BNL join)
Warnings:
Note 1003 select `test`.`t2`.`a` AS `a` from `test`.`t2` where <expr_cache><`test`.`t2`.`a`>(<in_optimizer>(`test`.`t2`.`a`,<exists>(<primary_index_lookup>(<cache>(`test`.`t2`.`a`) in t1 on PRIMARY))))
Note 1003 select `test`.`t2`.`a` AS `a` from `test`.`t1` join `test`.`t2` where (`test`.`t1`.`a` = `test`.`t2`.`a`)
select * from t2 where t2.a in (select a from t1 where t1.b <> 30);
a
2
4
explain extended select * from t2 where t2.a in (select a from t1 where t1.b <> 30);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t2 index NULL PRIMARY 4 NULL 4 100.00 Using where; Using index
2 DEPENDENT SUBQUERY t1 unique_subquery PRIMARY PRIMARY 4 func 1 100.00 Using where
1 PRIMARY t2 index PRIMARY PRIMARY 4 NULL 4 100.00 Using index
1 PRIMARY t1 ALL PRIMARY NULL NULL NULL 4 75.00 Using where; Using join buffer (flat, BNL join)
Warnings:
Note 1003 select `test`.`t2`.`a` AS `a` from `test`.`t2` where <expr_cache><`test`.`t2`.`a`>(<in_optimizer>(`test`.`t2`.`a`,<exists>(<primary_index_lookup>(<cache>(`test`.`t2`.`a`) in t1 on PRIMARY where ((`test`.`t1`.`b` <> 30) and (<cache>(`test`.`t2`.`a`) = `test`.`t1`.`a`))))))
Note 1003 select `test`.`t2`.`a` AS `a` from `test`.`t1` join `test`.`t2` where ((`test`.`t1`.`a` = `test`.`t2`.`a`) and (`test`.`t1`.`b` <> 30))
select * from t2 where t2.a in (select t1.a from t1,t3 where t1.b=t3.a);
a
2
3
explain extended select * from t2 where t2.a in (select t1.a from t1,t3 where t1.b=t3.a);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t2 index NULL PRIMARY 4 NULL 4 100.00 Using where; Using index
2 DEPENDENT SUBQUERY t1 eq_ref PRIMARY PRIMARY 4 func 1 100.00 Using where
2 DEPENDENT SUBQUERY t3 eq_ref PRIMARY PRIMARY 4 test.t1.b 1 100.00 Using index
1 PRIMARY t2 index PRIMARY PRIMARY 4 NULL 4 100.00 Using index
1 PRIMARY t1 ALL PRIMARY NULL NULL NULL 4 75.00 Using where; Using join buffer (flat, BNL join)
1 PRIMARY t3 eq_ref PRIMARY PRIMARY 4 test.t1.b 1 100.00 Using index
Warnings:
Note 1003 select `test`.`t2`.`a` AS `a` from `test`.`t2` where <expr_cache><`test`.`t2`.`a`>(<in_optimizer>(`test`.`t2`.`a`,<exists>(select `test`.`t1`.`a` from `test`.`t1` join `test`.`t3` where ((`test`.`t3`.`a` = `test`.`t1`.`b`) and (<cache>(`test`.`t2`.`a`) = `test`.`t1`.`a`)))))
Note 1003 select `test`.`t2`.`a` AS `a` from `test`.`t1` join `test`.`t3` join `test`.`t2` where ((`test`.`t1`.`a` = `test`.`t2`.`a`) and (`test`.`t3`.`a` = `test`.`t1`.`b`))
drop table t1, t2, t3;
create table t1 (a int, b int, index a (a,b));
create table t2 (a int, index a (a));
...
...
@@ -1340,31 +1340,31 @@ a
4
explain extended select * from t2 where t2.a in (select a from t1);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t2 index NULL a 5 NULL 4 100.00 Using where; Using index
2 DEPENDENT SUBQUERY t1 index_subquery a a 5 func 1 100.00 Using index
1 PRIMARY t2 index a a 5 NULL 4 100.00 Using where; Using index
1 PRIMARY t1 ref a a 5 test.t2.a 1 100.00 Using index; FirstMatch(t2)
Warnings:
Note 1003 select `test`.`t2`.`a` AS `a` from `test`.`t2` where <expr_cache><`test`.`t2`.`a`>(<in_optimizer>(`test`.`t2`.`a`,<exists>(<index_lookup>(<cache>(`test`.`t2`.`a`) in t1 on a))))
Note 1003 select `test`.`t2`.`a` AS `a` from `test`.`t2` semi join (`test`.`t1`) where (`test`.`t1`.`a` = `test`.`t2`.`a`)
select * from t2 where t2.a in (select a from t1 where t1.b <> 30);
a
2
4
explain extended select * from t2 where t2.a in (select a from t1 where t1.b <> 30);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t2 index NULL a 5 NULL 4 100.00 Using where; Using index
2 DEPENDENT SUBQUERY t1 index_subquery a a 5 func 1 100.00 Using index; Using where
1 PRIMARY t2 index a a 5 NULL 4 100.00 Using where; Using index
1 PRIMARY t1 ref a a 5 test.t2.a 1 100.00 Using where; Using index; FirstMatch(t2)
Warnings:
Note 1003 select `test`.`t2`.`a` AS `a` from `test`.`t2` where <expr_cache><`test`.`t2`.`a`>(<in_optimizer>(`test`.`t2`.`a`,<exists>(<index_lookup>(<cache>(`test`.`t2`.`a`) in t1 on a where ((`test`.`t1`.`b` <> 30) and (<cache>(`test`.`t2`.`a`) = `test`.`t1`.`a`))))))
Note 1003 select `test`.`t2`.`a` AS `a` from `test`.`t2` semi join (`test`.`t1`) where ((`test`.`t1`.`a` = `test`.`t2`.`a`) and (`test`.`t1`.`b` <> 30))
select * from t2 where t2.a in (select t1.a from t1,t3 where t1.b=t3.a);
a
2
3
explain extended select * from t2 where t2.a in (select t1.a from t1,t3 where t1.b=t3.a);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t2 index NULL a 5 NULL 4 100.00 Using where; Using index
2 DEPENDENT SUBQUERY t1 ref a a 5 func 1 100.00 Using where; Using index
2 DEPENDENT SUBQUERY t3 ref a a 5 test.t1.b 1 100.00 Using index
1 PRIMARY t2 index a a 5 NULL 4 100.00 Using where; Using index; Start temporary
1 PRIMARY t1 ref a a 5 test.t2.a 1 100.00 Using index
1 PRIMARY t3 index a a 5 NULL 3 100.00 Using where; Using index; End temporary; Using join buffer (flat, BNL join)
Warnings:
Note 1003 select `test`.`t2`.`a` AS `a` from `test`.`t2` where <expr_cache><`test`.`t2`.`a`>(<in_optimizer>(`test`.`t2`.`a`,<exists>(select `test`.`t1`.`a` from `test`.`t1` join `test`.`t3` where ((`test`.`t3`.`a` = `test`.`t1`.`b`) and (<cache>(`test`.`t2`.`a`) = `test`.`t1`.`a`)))))
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`.`t3`.`a` = `test`.`t1`.`b`))
insert into t1 values (3,31);
select * from t2 where t2.a in (select a from t1 where t1.b <> 30);
a
...
...
@@ -1377,10 +1377,10 @@ a
4
explain extended select * from t2 where t2.a in (select a from t1 where t1.b <> 30);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t2 index NULL a 5 NULL 4 100.00 Using where; Using index
2 DEPENDENT SUBQUERY t1 index_subquery a a 5 func 1 100.00 Using index; Using where
1 PRIMARY t2 index a a 5 NULL 4 100.00 Using where; Using index
1 PRIMARY t1 ref a a 5 test.t2.a 1 100.00 Using where; Using index; FirstMatch(t2)
Warnings:
Note 1003 select `test`.`t2`.`a` AS `a` from `test`.`t2` where <expr_cache><`test`.`t2`.`a`>(<in_optimizer>(`test`.`t2`.`a`,<exists>(<index_lookup>(<cache>(`test`.`t2`.`a`) in t1 on a where ((`test`.`t1`.`b` <> 30) and (<cache>(`test`.`t2`.`a`) = `test`.`t1`.`a`))))))
Note 1003 select `test`.`t2`.`a` AS `a` from `test`.`t2` semi join (`test`.`t1`) where ((`test`.`t1`.`a` = `test`.`t2`.`a`) and (`test`.`t1`.`b` <> 30))
drop table t1, t2, t3;
create table t1 (a int, b int);
create table t2 (a int, b int);
...
...
@@ -2834,10 +2834,10 @@ Warnings:
Note 1003 select `test`.`t1`.`one` AS `one`,`test`.`t1`.`two` AS `two`,<expr_cache><`test`.`t1`.`one`,`test`.`t1`.`two`>(<in_optimizer>((`test`.`t1`.`one`,`test`.`t1`.`two`),<exists>(select `test`.`t2`.`one`,`test`.`t2`.`two` from `test`.`t2` where ((`test`.`t2`.`flag` = '0') and trigcond(((<cache>(`test`.`t1`.`one`) = `test`.`t2`.`one`) or isnull(`test`.`t2`.`one`))) and trigcond(((<cache>(`test`.`t1`.`two`) = `test`.`t2`.`two`) or isnull(`test`.`t2`.`two`)))) having (trigcond(<is_not_null_test>(`test`.`t2`.`one`)) and trigcond(<is_not_null_test>(`test`.`t2`.`two`)))))) AS `test` from `test`.`t1`
explain extended SELECT one,two from t1 where ROW(one,two) IN (SELECT one,two FROM t2 WHERE flag = 'N');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 8 100.00 Using where
2 DEPENDENT SUBQUERY t2 ALL NULL NULL NULL NULL 9 100.00 Using where
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)
Warnings:
Note 1003 select `test`.`t1`.`one` AS `one`,`test`.`t1`.`two` AS `two` from `test`.`t1` where <expr_cache><`test`.`t1`.`one`,`test`.`t1`.`two`>(<in_optimizer>((`test`.`t1`.`one`,`test`.`t1`.`two`),<exists>(select `test`.`t2`.`one`,`test`.`t2`.`two` from `test`.`t2` where ((`test`.`t2`.`flag` = 'N') and (<cache>(`test`.`t1`.`one`) = `test`.`t2`.`one`) and (<cache>(`test`.`t1`.`two`) = `test`.`t2`.`two`)))))
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;
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
...
...
@@ -4224,8 +4224,8 @@ CREATE INDEX I1 ON t1 (a);
CREATE INDEX I2 ON t1 (b);
EXPLAIN SELECT a,b FROM t1 WHERE b IN (SELECT a FROM t1);
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 2 Using where
2 DEPENDENT SUBQUERY t1 index_subquery I1 I1 2 func 1 Using index; Using where
1 PRIMARY t1 ALL I2 NULL NULL NULL 2 Using where
1 PRIMARY t1 ref I1 I1 2 test.t1.b 1 Using where; Using index; FirstMatch(t1)
SELECT a,b FROM t1 WHERE b IN (SELECT a FROM t1);
a b
CREATE TABLE t2 (a VARCHAR(1), b VARCHAR(10));
...
...
@@ -4234,15 +4234,15 @@ CREATE INDEX I1 ON t2 (a);
CREATE INDEX I2 ON t2 (b);
EXPLAIN SELECT a,b FROM t2 WHERE b IN (SELECT a FROM t2);
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t2 ALL NULL NULL NULL NULL 2 Using where
2 DEPENDENT SUBQUERY t2 index_subquery I1 I1 4 func 1 Using index; Using where
1 PRIMARY t2 ALL I2 NULL NULL NULL 2 Using where
1 PRIMARY t2 ref I1 I1 4 test.t2.b 1 Using where; Using index; FirstMatch(t2)
SELECT a,b FROM t2 WHERE b IN (SELECT a FROM t2);
a b
EXPLAIN
SELECT a,b FROM t1 WHERE b IN (SELECT a FROM t1 WHERE LENGTH(a)<500);
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 2 Using where
2 DEPENDENT SUBQUERY t1 index_subquery I1 I1 2 func 1 Using index; Using where
1 PRIMARY t1 ALL I2 NULL NULL NULL 2 Using where
1 PRIMARY t1 ref I1 I1 2 test.t1.b 1 Using where; Using index; FirstMatch(t1)
SELECT a,b FROM t1 WHERE b IN (SELECT a FROM t1 WHERE LENGTH(a)<500);
