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|
drop table if exists t1, t2, t3, t1i, t2i, t3i;
create table t1 (a1 char(8), a2 char(8));
create temporary table t2 (b1 char(8), b2 char(8)) ENGINE=MyISAM;
create table t3 (c1 char(8), c2 char(8));
insert into t1 values ('1 - 00', '2 - 00');
insert into t1 values ('1 - 01', '2 - 01');
insert into t1 values ('1 - 02', '2 - 02');
insert into t2 values ('1 - 01', '2 - 01');
insert into t2 values ('1 - 01', '2 - 01');
insert into t2 values ('1 - 02', '2 - 02');
insert into t2 values ('1 - 02', '2 - 02');
insert into t2 values ('1 - 03', '2 - 03');
insert into t3 values ('1 - 01', '2 - 01');
insert into t3 values ('1 - 02', '2 - 02');
insert into t3 values ('1 - 03', '2 - 03');
insert into t3 values ('1 - 04', '2 - 04');
create temporary table t1i (a1 char(8), a2 char(8)) ENGINE=MyISAM;
create table t2i (b1 char(8), b2 char(8));
create temporary table t3i (c1 char(8), c2 char(8)) ENGINE=MyISAM;
create index it1i1 on t1i (a1);
create index it1i2 on t1i (a2);
create index it1i3 on t1i (a1, a2);
create index it2i1 on t2i (b1);
create index it2i2 on t2i (b2);
create index it2i3 on t2i (b1, b2);
create index it3i1 on t3i (c1);
create index it3i2 on t3i (c2);
create index it3i3 on t3i (c1, c2);
insert into t1i select * from t1;
insert into t2i select * from t2;
insert into t3i select * from t3;
/********************************************************************
* Simple tests.
********************************************************************/
# non-indexed nullable fields
explain extended
select * from t1 where a1 in (select b1 from t2 where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL # 100.00 Using where
2 SUBQUERY t2 ALL NULL NULL NULL NULL # 100.00 Using where
Warnings:
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where <in_optimizer>(`test`.`t1`.`a1`,`test`.`t1`.`a1` in ( <materialize> (select `test`.`t2`.`b1` AS `b1` from `test`.`t2` where (`test`.`t2`.`b1` > '0') ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key)))
select * from t1 where a1 in (select b1 from t2 where b1 > '0');
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
explain extended
select * from t1 where a1 in (select b1 from t2 where b1 > '0' group by b1);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL # 100.00 Using where
2 SUBQUERY t2 ALL NULL NULL NULL NULL # 100.00 Using where; Using temporary; Using filesort
Warnings:
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where <in_optimizer>(`test`.`t1`.`a1`,`test`.`t1`.`a1` in ( <materialize> (select `test`.`t2`.`b1` AS `b1` from `test`.`t2` where (`test`.`t2`.`b1` > '0') group by `test`.`t2`.`b1` ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key)))
select * from t1 where a1 in (select b1 from t2 where b1 > '0' group by b1);
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
explain extended
select * from t1 where (a1, a2) in (select b1, b2 from t2 where b1 > '0' group by b1, b2);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL # 100.00 Using where
2 SUBQUERY t2 ALL NULL NULL NULL NULL # 100.00 Using where; Using temporary; Using filesort
Warnings:
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where <in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),(`test`.`t1`.`a1`,`test`.`t1`.`a2`) in ( <materialize> (select `test`.`t2`.`b1` AS `b1`,`test`.`t2`.`b2` AS `b2` from `test`.`t2` where (`test`.`t2`.`b1` > '0') group by `test`.`t2`.`b1`,`test`.`t2`.`b2` ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key)))
select * from t1 where (a1, a2) in (select b1, b2 from t2 where b1 > '0' group by b1, b2);
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
explain extended
select * from t1 where (a1, a2) in (select b1, min(b2) from t2 where b1 > '0' group by b1);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL # 100.00 Using where
2 SUBQUERY t2 ALL NULL NULL NULL NULL # 100.00 Using where; Using temporary; Using filesort
Warnings:
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where <in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),(`test`.`t1`.`a1`,`test`.`t1`.`a2`) in ( <materialize> (select `test`.`t2`.`b1` AS `b1`,min(`test`.`t2`.`b2`) AS `min(b2)` from `test`.`t2` where (`test`.`t2`.`b1` > '0') group by `test`.`t2`.`b1` ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key)))
select * from t1 where (a1, a2) in (select b1, min(b2) from t2 where b1 > '0' group by b1);
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
explain extended
select * from t1i where a1 in (select b1 from t2i where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1i index NULL it1i3 70 NULL # 100.00 Using where; Using index
2 SUBQUERY t2i index it2i1,it2i3 it2i1 35 NULL # 100.00 Using where; Using index
Warnings:
Note 1003 select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from `test`.`t1i` where <in_optimizer>(`test`.`t1i`.`a1`,`test`.`t1i`.`a1` in ( <materialize> (select `test`.`t2i`.`b1` AS `b1` from `test`.`t2i` where (`test`.`t2i`.`b1` > '0') ), <primary_index_lookup>(`test`.`t1i`.`a1` in <temporary table> on distinct_key)))
select * from t1i where a1 in (select b1 from t2i where b1 > '0');
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
explain extended
select * from t1i where a1 in (select b1 from t2i where b1 > '0' group by b1);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1i index NULL it1i3 70 NULL # 100.00 Using where; Using index
2 SUBQUERY t2i index it2i1,it2i3 it2i1 35 NULL # 100.00 Using where; Using index
Warnings:
Note 1003 select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from `test`.`t1i` where <in_optimizer>(`test`.`t1i`.`a1`,`test`.`t1i`.`a1` in ( <materialize> (select `test`.`t2i`.`b1` AS `b1` from `test`.`t2i` where (`test`.`t2i`.`b1` > '0') group by `test`.`t2i`.`b1` ), <primary_index_lookup>(`test`.`t1i`.`a1` in <temporary table> on distinct_key)))
select * from t1i where a1 in (select b1 from t2i where b1 > '0' group by b1);
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
explain extended
select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1i index NULL it1i3 70 NULL # 100.00 Using where; Using index
2 SUBQUERY t2i index it2i1,it2i3 it2i3 70 NULL # 100.00 Using where; Using index
Warnings:
Note 1003 select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from `test`.`t1i` where <in_optimizer>((`test`.`t1i`.`a1`,`test`.`t1i`.`a2`),(`test`.`t1i`.`a1`,`test`.`t1i`.`a2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b1` > '0') ), <primary_index_lookup>(`test`.`t1i`.`a1` in <temporary table> on distinct_key)))
select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0');
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
explain extended
select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0' group by b1, b2);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1i index NULL it1i3 70 NULL # 100.00 Using where; Using index
2 SUBQUERY t2i index it2i1,it2i3 it2i3 70 NULL # 100.00 Using where; Using index
Warnings:
Note 1003 select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from `test`.`t1i` where <in_optimizer>((`test`.`t1i`.`a1`,`test`.`t1i`.`a2`),(`test`.`t1i`.`a1`,`test`.`t1i`.`a2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b1` > '0') group by `test`.`t2i`.`b1`,`test`.`t2i`.`b2` ), <primary_index_lookup>(`test`.`t1i`.`a1` in <temporary table> on distinct_key)))
select * from t1i where (a1, a2) in (select b1, b2 from t2i where b1 > '0' group by b1, b2);
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
explain extended
select * from t1i where (a1, a2) in (select b1, min(b2) from t2i where b1 > '0' group by b1);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1i index NULL it1i3 70 NULL # 100.00 Using where; Using index
2 SUBQUERY t2i index it2i1,it2i3 it2i1 35 NULL # 100.00 Using where
Warnings:
Note 1003 select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from `test`.`t1i` where <in_optimizer>((`test`.`t1i`.`a1`,`test`.`t1i`.`a2`),(`test`.`t1i`.`a1`,`test`.`t1i`.`a2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,min(`test`.`t2i`.`b2`) AS `min(b2)` from `test`.`t2i` where (`test`.`t2i`.`b1` > '0') group by `test`.`t2i`.`b1` ), <primary_index_lookup>(`test`.`t1i`.`a1` in <temporary table> on distinct_key)))
select * from t1i where (a1, a2) in (select b1, min(b2) from t2i where b1 > '0' group by b1);
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
explain extended
select * from t1 where (a1, a2) in (select b1, b2 from t2 order by b1, b2);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL # 100.00 Using where
2 SUBQUERY t2 ALL NULL NULL NULL NULL # 100.00
Warnings:
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where <in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),(`test`.`t1`.`a1`,`test`.`t1`.`a2`) in ( <materialize> (select `test`.`t2`.`b1` AS `b1`,`test`.`t2`.`b2` AS `b2` from `test`.`t2` order by `test`.`t2`.`b1`,`test`.`t2`.`b2` ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key)))
select * from t1 where (a1, a2) in (select b1, b2 from t2 order by b1, b2);
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
explain extended
select * from t1i where (a1, a2) in (select b1, b2 from t2i order by b1, b2);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1i index NULL it1i3 70 NULL # 100.00 Using where; Using index
2 SUBQUERY t2i index NULL it2i3 70 NULL # 100.00 Using index
Warnings:
Note 1003 select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from `test`.`t1i` where <in_optimizer>((`test`.`t1i`.`a1`,`test`.`t1i`.`a2`),(`test`.`t1i`.`a1`,`test`.`t1i`.`a2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` order by `test`.`t2i`.`b1`,`test`.`t2i`.`b2` ), <primary_index_lookup>(`test`.`t1i`.`a1` in <temporary table> on distinct_key)))
select * from t1i where (a1, a2) in (select b1, b2 from t2i order by b1, b2);
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
explain extended
select * from t1
where (a1, a2) in (select b1, b2 from t2 where b1 > '0') and
(a1, a2) in (select c1, c2 from t3
where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL # 100.00 Using where
3 SUBQUERY t3 ALL NULL NULL NULL NULL # 100.00 Using where
4 SUBQUERY t2i index it2i2 it2i3 70 NULL # 100.00 Using where; Using index
2 SUBQUERY t2 ALL NULL NULL NULL NULL # 100.00 Using where
Warnings:
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where (<in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),(`test`.`t1`.`a1`,`test`.`t1`.`a2`) in ( <materialize> (select `test`.`t2`.`b1` AS `b1`,`test`.`t2`.`b2` AS `b2` from `test`.`t2` where (`test`.`t2`.`b1` > '0') ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key))) and <in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),(`test`.`t1`.`a1`,`test`.`t1`.`a2`) in ( <materialize> (select `test`.`t3`.`c1` AS `c1`,`test`.`t3`.`c2` AS `c2` from `test`.`t3` where <in_optimizer>((`test`.`t3`.`c1`,`test`.`t3`.`c2`),(`test`.`t3`.`c1`,`test`.`t3`.`c2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b2` > '0') ), <primary_index_lookup>(`test`.`t3`.`c1` in <temporary table> on distinct_key))) ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key))))
select * from t1
where (a1, a2) in (select b1, b2 from t2 where b1 > '0') and
(a1, a2) in (select c1, c2 from t3
where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
explain extended
select * from t1i
where (a1, a2) in (select b1, b2 from t2i where b1 > '0') and
(a1, a2) in (select c1, c2 from t3i
where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1i index NULL it1i3 70 NULL # 100.00 Using where; Using index
3 SUBQUERY t3i index NULL it3i3 70 NULL # 100.00 Using where; Using index
4 SUBQUERY t2i index it2i2 it2i3 70 NULL # 100.00 Using where; Using index
2 SUBQUERY t2i index it2i1,it2i3 it2i3 70 NULL # 100.00 Using where; Using index
Warnings:
Note 1003 select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from `test`.`t1i` where (<in_optimizer>((`test`.`t1i`.`a1`,`test`.`t1i`.`a2`),(`test`.`t1i`.`a1`,`test`.`t1i`.`a2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b1` > '0') ), <primary_index_lookup>(`test`.`t1i`.`a1` in <temporary table> on distinct_key))) and <in_optimizer>((`test`.`t1i`.`a1`,`test`.`t1i`.`a2`),(`test`.`t1i`.`a1`,`test`.`t1i`.`a2`) in ( <materialize> (select `test`.`t3i`.`c1` AS `c1`,`test`.`t3i`.`c2` AS `c2` from `test`.`t3i` where <in_optimizer>((`test`.`t3i`.`c1`,`test`.`t3i`.`c2`),(`test`.`t3i`.`c1`,`test`.`t3i`.`c2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b2` > '0') ), <primary_index_lookup>(`test`.`t3i`.`c1` in <temporary table> on distinct_key))) ), <primary_index_lookup>(`test`.`t1i`.`a1` in <temporary table> on distinct_key))))
select * from t1i
where (a1, a2) in (select b1, b2 from t2i where b1 > '0') and
(a1, a2) in (select c1, c2 from t3i
where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
explain extended
select * from t1
where (a1, a2) in (select b1, b2 from t2
where b2 in (select c2 from t3 where c2 LIKE '%02') or
b2 in (select c2 from t3 where c2 LIKE '%03')) and
(a1, a2) in (select c1, c2 from t3
where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL # 100.00 Using where
5 SUBQUERY t3 ALL NULL NULL NULL NULL # 100.00 Using where
6 SUBQUERY t2i index it2i2 it2i3 70 NULL # 100.00 Using where; Using index
2 SUBQUERY t2 ALL NULL NULL NULL NULL # 100.00 Using where
4 SUBQUERY t3 ALL NULL NULL NULL NULL # 100.00 Using where
3 SUBQUERY t3 ALL NULL NULL NULL NULL # 100.00 Using where
Warnings:
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where (<in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),(`test`.`t1`.`a1`,`test`.`t1`.`a2`) in ( <materialize> (select `test`.`t2`.`b1` AS `b1`,`test`.`t2`.`b2` AS `b2` from `test`.`t2` where (<in_optimizer>(`test`.`t2`.`b2`,`test`.`t2`.`b2` in ( <materialize> (select `test`.`t3`.`c2` AS `c2` from `test`.`t3` where (`test`.`t3`.`c2` like '%02') ), <primary_index_lookup>(`test`.`t2`.`b2` in <temporary table> on distinct_key))) or <in_optimizer>(`test`.`t2`.`b2`,`test`.`t2`.`b2` in ( <materialize> (select `test`.`t3`.`c2` AS `c2` from `test`.`t3` where (`test`.`t3`.`c2` like '%03') ), <primary_index_lookup>(`test`.`t2`.`b2` in <temporary table> on distinct_key)))) ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key))) and <in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),(`test`.`t1`.`a1`,`test`.`t1`.`a2`) in ( <materialize> (select `test`.`t3`.`c1` AS `c1`,`test`.`t3`.`c2` AS `c2` from `test`.`t3` where <in_optimizer>((`test`.`t3`.`c1`,`test`.`t3`.`c2`),(`test`.`t3`.`c1`,`test`.`t3`.`c2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b2` > '0') ), <primary_index_lookup>(`test`.`t3`.`c1` in <temporary table> on distinct_key))) ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key))))
select * from t1
where (a1, a2) in (select b1, b2 from t2
where b2 in (select c2 from t3 where c2 LIKE '%02') or
b2 in (select c2 from t3 where c2 LIKE '%03')) and
(a1, a2) in (select c1, c2 from t3
where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
a1 a2
1 - 02 2 - 02
explain extended
select * from t1
where (a1, a2) in (select b1, b2 from t2
where b2 in (select c2 from t3 t3a where c1 = a1) or
b2 in (select c2 from t3 t3b where c2 LIKE '%03')) and
(a1, a2) in (select c1, c2 from t3 t3c
where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL # 100.00 Using where
5 SUBQUERY t3c ALL NULL NULL NULL NULL # 100.00 Using where
6 SUBQUERY t2i index it2i2 it2i3 70 NULL # 100.00 Using where; Using index
2 DEPENDENT SUBQUERY t2 ALL NULL NULL NULL NULL # 100.00 Using where
4 SUBQUERY t3b ALL NULL NULL NULL NULL # 100.00 Using where
3 DEPENDENT SUBQUERY t3a ALL NULL NULL NULL NULL # 100.00 Using where
Warnings:
Note 1276 Field or reference 'test.t1.a1' of SELECT #3 was resolved in SELECT #1
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where (<in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),<exists>(select `test`.`t2`.`b1` AS `b1`,`test`.`t2`.`b2` AS `b2` from `test`.`t2` where ((<in_optimizer>(`test`.`t2`.`b2`,<exists>(select 1 AS `Not_used` from `test`.`t3` `t3a` where ((`test`.`t3a`.`c1` = `test`.`t1`.`a1`) and (<cache>(`test`.`t2`.`b2`) = `test`.`t3a`.`c2`)))) or <in_optimizer>(`test`.`t2`.`b2`,`test`.`t2`.`b2` in ( <materialize> (select `test`.`t3b`.`c2` AS `c2` from `test`.`t3` `t3b` where (`test`.`t3b`.`c2` like '%03') ), <primary_index_lookup>(`test`.`t2`.`b2` in <temporary table> on distinct_key)))) and (<cache>(`test`.`t1`.`a1`) = `test`.`t2`.`b1`) and (<cache>(`test`.`t1`.`a2`) = `test`.`t2`.`b2`)))) and <in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),(`test`.`t1`.`a1`,`test`.`t1`.`a2`) in ( <materialize> (select `test`.`t3c`.`c1` AS `c1`,`test`.`t3c`.`c2` AS `c2` from `test`.`t3` `t3c` where <in_optimizer>((`test`.`t3c`.`c1`,`test`.`t3c`.`c2`),(`test`.`t3c`.`c1`,`test`.`t3c`.`c2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b2` > '0') ), <primary_index_lookup>(`test`.`t3c`.`c1` in <temporary table> on distinct_key))) ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key))))
select * from t1
where (a1, a2) in (select b1, b2 from t2
where b2 in (select c2 from t3 t3a where c1 = a1) or
b2 in (select c2 from t3 t3b where c2 LIKE '%03')) and
(a1, a2) in (select c1, c2 from t3 t3c
where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
explain extended
(select * from t1
where (a1, a2) in (select b1, b2 from t2
where b2 in (select c2 from t3 where c2 LIKE '%02') or
b2 in (select c2 from t3 where c2 LIKE '%03')
group by b1, b2) and
(a1, a2) in (select c1, c2 from t3
where (c1, c2) in (select b1, b2 from t2i where b2 > '0')))
UNION
(select * from t1i
where (a1, a2) in (select b1, b2 from t2i where b1 > '0') and
(a1, a2) in (select c1, c2 from t3i
where (c1, c2) in (select b1, b2 from t2i where b2 > '0')));
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL # 100.00 Using where
5 SUBQUERY t3 ALL NULL NULL NULL NULL # 100.00 Using where
6 SUBQUERY t2i index it2i2 it2i3 70 NULL # 100.00 Using where; Using index
2 SUBQUERY t2 ALL NULL NULL NULL NULL # 100.00 Using where; Using temporary; Using filesort
4 SUBQUERY t3 ALL NULL NULL NULL NULL # 100.00 Using where
3 SUBQUERY t3 ALL NULL NULL NULL NULL # 100.00 Using where
7 UNION t1i index NULL it1i3 70 NULL # 100.00 Using where; Using index
9 SUBQUERY t3i index NULL it3i3 70 NULL # 100.00 Using where; Using index
10 SUBQUERY t2i index it2i2 it2i3 70 NULL # 100.00 Using where; Using index
8 SUBQUERY t2i index it2i1,it2i3 it2i3 70 NULL # 100.00 Using where; Using index
NULL UNION RESULT <union1,7> ALL NULL NULL NULL NULL # NULL
Warnings:
Note 1003 (select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where (<in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),(`test`.`t1`.`a1`,`test`.`t1`.`a2`) in ( <materialize> (select `test`.`t2`.`b1` AS `b1`,`test`.`t2`.`b2` AS `b2` from `test`.`t2` where (<in_optimizer>(`test`.`t2`.`b2`,`test`.`t2`.`b2` in ( <materialize> (select `test`.`t3`.`c2` AS `c2` from `test`.`t3` where (`test`.`t3`.`c2` like '%02') ), <primary_index_lookup>(`test`.`t2`.`b2` in <temporary table> on distinct_key))) or <in_optimizer>(`test`.`t2`.`b2`,`test`.`t2`.`b2` in ( <materialize> (select `test`.`t3`.`c2` AS `c2` from `test`.`t3` where (`test`.`t3`.`c2` like '%03') ), <primary_index_lookup>(`test`.`t2`.`b2` in <temporary table> on distinct_key)))) group by `test`.`t2`.`b1`,`test`.`t2`.`b2` ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key))) and <in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),(`test`.`t1`.`a1`,`test`.`t1`.`a2`) in ( <materialize> (select `test`.`t3`.`c1` AS `c1`,`test`.`t3`.`c2` AS `c2` from `test`.`t3` where <in_optimizer>((`test`.`t3`.`c1`,`test`.`t3`.`c2`),(`test`.`t3`.`c1`,`test`.`t3`.`c2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b2` > '0') ), <primary_index_lookup>(`test`.`t3`.`c1` in <temporary table> on distinct_key))) ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key))))) union (select `test`.`t1i`.`a1` AS `a1`,`test`.`t1i`.`a2` AS `a2` from `test`.`t1i` where (<in_optimizer>((`test`.`t1i`.`a1`,`test`.`t1i`.`a2`),(`test`.`t1i`.`a1`,`test`.`t1i`.`a2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b1` > '0') ), <primary_index_lookup>(`test`.`t1i`.`a1` in <temporary table> on distinct_key))) and <in_optimizer>((`test`.`t1i`.`a1`,`test`.`t1i`.`a2`),(`test`.`t1i`.`a1`,`test`.`t1i`.`a2`) in ( <materialize> (select `test`.`t3i`.`c1` AS `c1`,`test`.`t3i`.`c2` AS `c2` from `test`.`t3i` where <in_optimizer>((`test`.`t3i`.`c1`,`test`.`t3i`.`c2`),(`test`.`t3i`.`c1`,`test`.`t3i`.`c2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b2` > '0') ), <primary_index_lookup>(`test`.`t3i`.`c1` in <temporary table> on distinct_key))) ), <primary_index_lookup>(`test`.`t1i`.`a1` in <temporary table> on distinct_key)))))
(select * from t1
where (a1, a2) in (select b1, b2 from t2
where b2 in (select c2 from t3 where c2 LIKE '%02') or
b2 in (select c2 from t3 where c2 LIKE '%03')
group by b1, b2) and
(a1, a2) in (select c1, c2 from t3
where (c1, c2) in (select b1, b2 from t2i where b2 > '0')))
UNION
(select * from t1i
where (a1, a2) in (select b1, b2 from t2i where b1 > '0') and
(a1, a2) in (select c1, c2 from t3i
where (c1, c2) in (select b1, b2 from t2i where b2 > '0')));
a1 a2
1 - 02 2 - 02
1 - 01 2 - 01
explain extended
select * from t1
where (a1, a2) in (select * from t1 where a1 > '0' UNION select * from t2 where b1 < '9') and
(a1, a2) in (select c1, c2 from t3
where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL # 100.00 Using where
4 SUBQUERY t3 ALL NULL NULL NULL NULL # 100.00 Using where
5 SUBQUERY t2i index it2i2 it2i3 70 NULL # 100.00 Using where; Using index
2 DEPENDENT SUBQUERY t1 ALL NULL NULL NULL NULL # 100.00 Using where
3 DEPENDENT UNION t2 ALL NULL NULL NULL NULL # 100.00 Using where
NULL UNION RESULT <union2,3> ALL NULL NULL NULL NULL # NULL
Warnings:
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where (<in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),<exists>(select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where ((`test`.`t1`.`a1` > '0') and (<cache>(`test`.`t1`.`a1`) = `test`.`t1`.`a1`) and (<cache>(`test`.`t1`.`a2`) = `test`.`t1`.`a2`)) union select `test`.`t2`.`b1` AS `b1`,`test`.`t2`.`b2` AS `b2` from `test`.`t2` where ((`test`.`t2`.`b1` < '9') and (<cache>(`test`.`t1`.`a1`) = `test`.`t2`.`b1`) and (<cache>(`test`.`t1`.`a2`) = `test`.`t2`.`b2`)))) and <in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),(`test`.`t1`.`a1`,`test`.`t1`.`a2`) in ( <materialize> (select `test`.`t3`.`c1` AS `c1`,`test`.`t3`.`c2` AS `c2` from `test`.`t3` where <in_optimizer>((`test`.`t3`.`c1`,`test`.`t3`.`c2`),(`test`.`t3`.`c1`,`test`.`t3`.`c2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b2` > '0') ), <primary_index_lookup>(`test`.`t3`.`c1` in <temporary table> on distinct_key))) ), <primary_index_lookup>(`test`.`t1`.`a1` in <temporary table> on distinct_key))))
select * from t1
where (a1, a2) in (select * from t1 where a1 > '0' UNION select * from t2 where b1 < '9') and
(a1, a2) in (select c1, c2 from t3
where (c1, c2) in (select b1, b2 from t2i where b2 > '0'));
a1 a2
1 - 01 2 - 01
1 - 02 2 - 02
explain extended
select * from t1, t3
where (a1, a2) in (select * from t1 where a1 > '0' UNION select * from t2 where b1 < '9') and
(c1, c2) in (select c1, c2 from t3
where (c1, c2) in (select b1, b2 from t2i where b2 > '0')) and
a1 = c1;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL # 100.00 Using where
1 PRIMARY t3 ALL NULL NULL NULL NULL # 100.00 Using where; Using join buffer
4 SUBQUERY t3 ALL NULL NULL NULL NULL # 100.00 Using where
5 SUBQUERY t2i index it2i2 it2i3 70 NULL # 100.00 Using where; Using index
2 DEPENDENT SUBQUERY t1 ALL NULL NULL NULL NULL # 100.00 Using where
3 DEPENDENT UNION t2 ALL NULL NULL NULL NULL # 100.00 Using where
NULL UNION RESULT <union2,3> ALL NULL NULL NULL NULL # NULL
Warnings:
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2`,`test`.`t3`.`c1` AS `c1`,`test`.`t3`.`c2` AS `c2` from `test`.`t1` join `test`.`t3` where ((`test`.`t3`.`c1` = `test`.`t1`.`a1`) and <in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),<exists>(select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where ((`test`.`t1`.`a1` > '0') and (<cache>(`test`.`t1`.`a1`) = `test`.`t1`.`a1`) and (<cache>(`test`.`t1`.`a2`) = `test`.`t1`.`a2`)) union select `test`.`t2`.`b1` AS `b1`,`test`.`t2`.`b2` AS `b2` from `test`.`t2` where ((`test`.`t2`.`b1` < '9') and (<cache>(`test`.`t1`.`a1`) = `test`.`t2`.`b1`) and (<cache>(`test`.`t1`.`a2`) = `test`.`t2`.`b2`)))) and <in_optimizer>((`test`.`t3`.`c1`,`test`.`t3`.`c2`),(`test`.`t3`.`c1`,`test`.`t3`.`c2`) in ( <materialize> (select `test`.`t3`.`c1` AS `c1`,`test`.`t3`.`c2` AS `c2` from `test`.`t3` where <in_optimizer>((`test`.`t3`.`c1`,`test`.`t3`.`c2`),(`test`.`t3`.`c1`,`test`.`t3`.`c2`) in ( <materialize> (select `test`.`t2i`.`b1` AS `b1`,`test`.`t2i`.`b2` AS `b2` from `test`.`t2i` where (`test`.`t2i`.`b2` > '0') ), <primary_index_lookup>(`test`.`t3`.`c1` in <temporary table> on distinct_key))) ), <primary_index_lookup>(`test`.`t3`.`c1` in <temporary table> on distinct_key))))
select * from t1, t3
where (a1, a2) in (select * from t1 where a1 > '0' UNION select * from t2 where b1 < '9') and
(c1, c2) in (select c1, c2 from t3
where (c1, c2) in (select b1, b2 from t2i where b2 > '0')) and
a1 = c1;
a1 a2 c1 c2
1 - 01 2 - 01 1 - 01 2 - 01
1 - 02 2 - 02 1 - 02 2 - 02
/*********************************************************************
* Negative tests, where materialization should not be applied.
**********************************************************************/
# UNION in a subquery
explain extended
select * from t3
where c1 in (select a1 from t1 where a1 > '0' UNION select b1 from t2 where b1 < '9');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t3 ALL NULL NULL NULL NULL # 100.00 Using where
2 DEPENDENT SUBQUERY t1 ALL NULL NULL NULL NULL # 100.00 Using where
3 DEPENDENT UNION t2 ALL NULL NULL NULL NULL # 100.00 Using where
NULL UNION RESULT <union2,3> ALL NULL NULL NULL NULL # NULL
Warnings:
Note 1003 select `test`.`t3`.`c1` AS `c1`,`test`.`t3`.`c2` AS `c2` from `test`.`t3` where <in_optimizer>(`test`.`t3`.`c1`,<exists>(select 1 AS `Not_used` from `test`.`t1` where ((`test`.`t1`.`a1` > '0') and (<cache>(`test`.`t3`.`c1`) = `test`.`t1`.`a1`)) union select 1 AS `Not_used` from `test`.`t2` where ((`test`.`t2`.`b1` < '9') and (<cache>(`test`.`t3`.`c1`) = `test`.`t2`.`b1`))))
select * from t3
where c1 in (select a1 from t1 where a1 > '0' UNION select b1 from t2 where b1 < '9');
c1 c2
1 - 01 2 - 01
1 - 02 2 - 02
1 - 03 2 - 03
explain extended
select * from t1
where (a1, a2) in (select b1, b2 from t2
where b2 in (select c2 from t3 t3a where c1 = a1) or
b2 in (select c2 from t3 t3b where c2 LIKE '%03')) and
(a1, a2) in (select c1, c2 from t3 t3c
where (c1, c2) in (select b1, b2 from t2i where b2 > '0' or b2 = a2));
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL # 100.00 Using where
5 DEPENDENT SUBQUERY t3c ALL NULL NULL NULL NULL # 100.00 Using where
6 DEPENDENT SUBQUERY t2i index_subquery it2i1,it2i2,it2i3 it2i3 70 func,func # 100.00 Using index; Using where
2 DEPENDENT SUBQUERY t2 ALL NULL NULL NULL NULL # 100.00 Using where
4 SUBQUERY t3b ALL NULL NULL NULL NULL # 100.00 Using where
3 DEPENDENT SUBQUERY t3a ALL NULL NULL NULL NULL # 100.00 Using where
Warnings:
Note 1276 Field or reference 'test.t1.a1' of SELECT #3 was resolved in SELECT #1
Note 1276 Field or reference 'test.t1.a2' of SELECT #6 was resolved in SELECT #1
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where (<in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),<exists>(select `test`.`t2`.`b1` AS `b1`,`test`.`t2`.`b2` AS `b2` from `test`.`t2` where ((<in_optimizer>(`test`.`t2`.`b2`,<exists>(select 1 AS `Not_used` from `test`.`t3` `t3a` where ((`test`.`t3a`.`c1` = `test`.`t1`.`a1`) and (<cache>(`test`.`t2`.`b2`) = `test`.`t3a`.`c2`)))) or <in_optimizer>(`test`.`t2`.`b2`,`test`.`t2`.`b2` in ( <materialize> (select `test`.`t3b`.`c2` AS `c2` from `test`.`t3` `t3b` where (`test`.`t3b`.`c2` like '%03') ), <primary_index_lookup>(`test`.`t2`.`b2` in <temporary table> on distinct_key)))) and (<cache>(`test`.`t1`.`a1`) = `test`.`t2`.`b1`) and (<cache>(`test`.`t1`.`a2`) = `test`.`t2`.`b2`)))) and <in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),<exists>(select `test`.`t3c`.`c1` AS `c1`,`test`.`t3c`.`c2` AS `c2` from `test`.`t3` `t3c` where (<in_optimizer>((`test`.`t3c`.`c1`,`test`.`t3c`.`c2`),<exists>(<index_lookup>(<cache>(`test`.`t3c`.`c1`) in t2i on it2i3 where (((`test`.`t2i`.`b2` > '0') or (`test`.`t2i`.`b2` = `test`.`t1`.`a2`)) and (<cache>(`test`.`t3c`.`c1`) = `test`.`t2i`.`b1`) and (<cache>(`test`.`t3c`.`c2`) = `test`.`t2i`.`b2`))))) and (<cache>(`test`.`t1`.`a1`) = `test`.`t3c`.`c1`) and (<cache>(`test`.`t1`.`a2`) = `test`.`t3c`.`c2`)))))
DROP TABLE t1i, t2i, t3i;
explain extended
select * from t1 where (a1, a2) in (select '1 - 01', '2 - 01');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL # 100.00 Using where
2 DEPENDENT SUBQUERY NULL NULL NULL NULL NULL NULL # NULL No tables used
Warnings:
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where <in_optimizer>((`test`.`t1`.`a1`,`test`.`t1`.`a2`),<exists>(select '1 - 01' AS `1 - 01`,'2 - 01' AS `2 - 01` having ((<cache>(`test`.`t1`.`a1`) = '1 - 01') and (<cache>(`test`.`t1`.`a2`) = '2 - 01'))))
select * from t1 where (a1, a2) in (select '1 - 01', '2 - 01');
a1 a2
1 - 01 2 - 01
/******************************************************************************
* Subqueries in other uncovered clauses.
******************************************************************************/
/* SELECT clause */
select ((a1,a2) IN (select * from t2 where b2 > '0')) IS NULL from t1;
((a1,a2) IN (select * from t2 where b2 > '0')) IS NULL
0
0
0
/* GROUP BY clause */
create temporary table columns (col int key) ENGINE=MyISAM;
insert into columns values (1), (2);
explain extended
select * from t1 group by (select col from columns limit 1);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL # 100.00
2 SUBQUERY columns index NULL PRIMARY 4 NULL # 100.00 Using index
Warnings:
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` group by (select `test`.`columns`.`col` AS `col` from `test`.`columns` limit 1)
select * from t1 group by (select col from columns limit 1);
a1 a2
1 - 00 2 - 00
explain extended
select * from t1 group by (a1 in (select col from columns));
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL # 100.00 Using temporary; Using filesort
2 DEPENDENT SUBQUERY columns unique_subquery PRIMARY PRIMARY 4 func # 100.00 Using index; Using where; Full scan on NULL key
Warnings:
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` group by <in_optimizer>(`test`.`t1`.`a1`,<exists>(<primary_index_lookup>(<cache>(`test`.`t1`.`a1`) in columns on PRIMARY where trigcond((<cache>(`test`.`t1`.`a1`) = `test`.`columns`.`col`)))))
select * from t1 group by (a1 in (select col from columns));
a1 a2
1 - 00 2 - 00
/* ORDER BY clause */
explain extended
select * from t1 order by (select col from columns limit 1);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL # 100.00
2 SUBQUERY columns index NULL PRIMARY 4 NULL # 100.00 Using index
Warnings:
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` order by (select `test`.`columns`.`col` AS `col` from `test`.`columns` limit 1)
select * from t1 order by (select col from columns limit 1);
a1 a2
1 - 00 2 - 00
1 - 01 2 - 01
1 - 02 2 - 02
DROP TABLE columns;
/******************************************************************************
* Column types/sizes that affect materialization.
******************************************************************************/
/*
Test that BLOBs are not materialized (except when arguments of some functions).
*/
# force materialization to be always considered
set @prefix_len = 6;
set @blob_len = 16;
set @suffix_len = @blob_len - @prefix_len;
create temporary table t1_16 (a1 blob, a2 blob) ENGINE=MyISAM;
create temporary table t2_16 (b1 blob, b2 blob) ENGINE=MyISAM;
create temporary table t3_16 (c1 blob, c2 blob) ENGINE=MyISAM;
insert into t1_16 values
(concat('1 - 00', repeat('x', @suffix_len)), concat('2 - 00', repeat('x', @suffix_len)));
insert into t1_16 values
(concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
insert into t1_16 values
(concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
insert into t2_16 values
(concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
insert into t2_16 values
(concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
insert into t2_16 values
(concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len)));
insert into t3_16 values
(concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
insert into t3_16 values
(concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
insert into t3_16 values
(concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len)));
insert into t3_16 values
(concat('1 - 04', repeat('x', @suffix_len)), concat('2 - 04', repeat('x', @suffix_len)));
explain extended select left(a1,7), left(a2,7)
from t1_16
where a1 in (select b1 from t2_16 where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_16 ALL NULL NULL NULL NULL 3 100.00 Using where
2 DEPENDENT SUBQUERY t2_16 ALL NULL NULL NULL NULL 3 100.00 Using where
Warnings:
Note 1003 select left(`test`.`t1_16`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_16`.`a2`,7) AS `left(a2,7)` from `test`.`t1_16` where <in_optimizer>(`test`.`t1_16`.`a1`,`test`.`t1_16`.`a1` in (select 1 AS `Not_used` from `test`.`t2_16` where ((`test`.`t2_16`.`b1` > '0') and (<cache>(`test`.`t1_16`.`a1`) = `test`.`t2_16`.`b1`))))
select left(a1,7), left(a2,7)
from t1_16
where a1 in (select b1 from t2_16 where b1 > '0');
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
explain extended select left(a1,7), left(a2,7)
from t1_16
where (a1,a2) in (select b1, b2 from t2_16 where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_16 ALL NULL NULL NULL NULL 3 100.00 Using where
2 DEPENDENT SUBQUERY t2_16 ALL NULL NULL NULL NULL 3 100.00 Using where
Warnings:
Note 1003 select left(`test`.`t1_16`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_16`.`a2`,7) AS `left(a2,7)` from `test`.`t1_16` where <in_optimizer>((`test`.`t1_16`.`a1`,`test`.`t1_16`.`a2`),(`test`.`t1_16`.`a1`,`test`.`t1_16`.`a2`) in (select `test`.`t2_16`.`b1` AS `b1`,`test`.`t2_16`.`b2` AS `b2` from `test`.`t2_16` where ((`test`.`t2_16`.`b1` > '0') and (<cache>(`test`.`t1_16`.`a1`) = `test`.`t2_16`.`b1`) and (<cache>(`test`.`t1_16`.`a2`) = `test`.`t2_16`.`b2`))))
select left(a1,7), left(a2,7)
from t1_16
where (a1,a2) in (select b1, b2 from t2_16 where b1 > '0');
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
explain extended select left(a1,7), left(a2,7)
from t1_16
where a1 in (select substring(b1,1,16) from t2_16 where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_16 ALL NULL NULL NULL NULL 3 100.00 Using where
2 SUBQUERY t2_16 ALL NULL NULL NULL NULL 3 100.00 Using where
Warnings:
Note 1003 select left(`test`.`t1_16`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_16`.`a2`,7) AS `left(a2,7)` from `test`.`t1_16` where <in_optimizer>(`test`.`t1_16`.`a1`,`test`.`t1_16`.`a1` in ( <materialize> (select substr(`test`.`t2_16`.`b1`,1,16) AS `substring(b1,1,16)` from `test`.`t2_16` where (`test`.`t2_16`.`b1` > '0') ), <primary_index_lookup>(`test`.`t1_16`.`a1` in <temporary table> on distinct_key)))
select left(a1,7), left(a2,7)
from t1_16
where a1 in (select substring(b1,1,16) from t2_16 where b1 > '0');
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
explain extended select left(a1,7), left(a2,7)
from t1_16
where a1 in (select group_concat(b1) from t2_16 group by b2);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_16 ALL NULL NULL NULL NULL 3 100.00 Using where
2 DEPENDENT SUBQUERY t2_16 ALL NULL NULL NULL NULL 3 100.00 Using filesort
Warnings:
Note 1003 select left(`test`.`t1_16`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_16`.`a2`,7) AS `left(a2,7)` from `test`.`t1_16` where <in_optimizer>(`test`.`t1_16`.`a1`,`test`.`t1_16`.`a1` in (select group_concat(`test`.`t2_16`.`b1` separator ',') AS `group_concat(b1)` from `test`.`t2_16` group by `test`.`t2_16`.`b2` having (<cache>(`test`.`t1_16`.`a1`) = <ref_null_helper>(group_concat(`test`.`t2_16`.`b1` separator ',')))))
select left(a1,7), left(a2,7)
from t1_16
where a1 in (select group_concat(b1) from t2_16 group by b2);
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
set @@group_concat_max_len = 256;
explain extended select left(a1,7), left(a2,7)
from t1_16
where a1 in (select group_concat(b1) from t2_16 group by b2);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_16 ALL NULL NULL NULL NULL 3 100.00 Using where
2 SUBQUERY t2_16 ALL NULL NULL NULL NULL 3 100.00 Using filesort
Warnings:
Note 1003 select left(`test`.`t1_16`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_16`.`a2`,7) AS `left(a2,7)` from `test`.`t1_16` where <in_optimizer>(`test`.`t1_16`.`a1`,`test`.`t1_16`.`a1` in ( <materialize> (select group_concat(`test`.`t2_16`.`b1` separator ',') AS `group_concat(b1)` from `test`.`t2_16` group by `test`.`t2_16`.`b2` ), <primary_index_lookup>(`test`.`t1_16`.`a1` in <temporary table> on distinct_key)))
select left(a1,7), left(a2,7)
from t1_16
where a1 in (select group_concat(b1) from t2_16 group by b2);
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
explain extended
select * from t1
where concat(a1,'x') IN
(select left(a1,8) from t1_16
where (a1, a2) IN
(select t2_16.b1, t2_16.b2 from t2_16, t2
where t2.b2 = substring(t2_16.b2,1,6) and
t2.b1 IN (select c1 from t3 where c2 > '0')));
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 3 100.00 Using where
2 SUBQUERY t1_16 ALL NULL NULL NULL NULL 3 100.00 Using where
3 DEPENDENT SUBQUERY t2_16 ALL NULL NULL NULL NULL 3 100.00 Using where
3 DEPENDENT SUBQUERY t2 ALL NULL NULL NULL NULL 5 100.00 Using where; Using join buffer
4 SUBQUERY t3 ALL NULL NULL NULL NULL 4 100.00 Using where
Warnings:
Note 1003 select `test`.`t1`.`a1` AS `a1`,`test`.`t1`.`a2` AS `a2` from `test`.`t1` where <in_optimizer>(concat(`test`.`t1`.`a1`,'x'),concat(`test`.`t1`.`a1`,'x') in ( <materialize> (select left(`test`.`t1_16`.`a1`,8) AS `left(a1,8)` from `test`.`t1_16` where <in_optimizer>((`test`.`t1_16`.`a1`,`test`.`t1_16`.`a2`),(`test`.`t1_16`.`a1`,`test`.`t1_16`.`a2`) in (select `test`.`t2_16`.`b1` AS `b1`,`test`.`t2_16`.`b2` AS `b2` from `test`.`t2_16` join `test`.`t2` where ((`test`.`t2`.`b2` = substr(`test`.`t2_16`.`b2`,1,6)) and <in_optimizer>(`test`.`t2`.`b1`,`test`.`t2`.`b1` in ( <materialize> (select `test`.`t3`.`c1` AS `c1` from `test`.`t3` where (`test`.`t3`.`c2` > '0') ), <primary_index_lookup>(`test`.`t2`.`b1` in <temporary table> on distinct_key))) and (<cache>(`test`.`t1_16`.`a1`) = `test`.`t2_16`.`b1`) and (<cache>(`test`.`t1_16`.`a2`) = `test`.`t2_16`.`b2`)))) ), <primary_index_lookup>(concat(`test`.`t1`.`a1`,'x') in <temporary table> on distinct_key)))
drop table t1_16, t2_16, t3_16;
set @blob_len = 512;
set @suffix_len = @blob_len - @prefix_len;
create temporary table t1_512 (a1 blob, a2 blob) ENGINE=MyISAM;
create temporary table t2_512 (b1 blob, b2 blob) ENGINE=MyISAM;
create temporary table t3_512 (c1 blob, c2 blob) ENGINE=MyISAM;
insert into t1_512 values
(concat('1 - 00', repeat('x', @suffix_len)), concat('2 - 00', repeat('x', @suffix_len)));
insert into t1_512 values
(concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
insert into t1_512 values
(concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
insert into t2_512 values
(concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
insert into t2_512 values
(concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
insert into t2_512 values
(concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len)));
insert into t3_512 values
(concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
insert into t3_512 values
(concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
insert into t3_512 values
(concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len)));
insert into t3_512 values
(concat('1 - 04', repeat('x', @suffix_len)), concat('2 - 04', repeat('x', @suffix_len)));
explain extended select left(a1,7), left(a2,7)
from t1_512
where a1 in (select b1 from t2_512 where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_512 ALL NULL NULL NULL NULL 3 100.00 Using where
2 DEPENDENT SUBQUERY t2_512 ALL NULL NULL NULL NULL 3 100.00 Using where
Warnings:
Note 1003 select left(`test`.`t1_512`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_512`.`a2`,7) AS `left(a2,7)` from `test`.`t1_512` where <in_optimizer>(`test`.`t1_512`.`a1`,`test`.`t1_512`.`a1` in (select 1 AS `Not_used` from `test`.`t2_512` where ((`test`.`t2_512`.`b1` > '0') and (<cache>(`test`.`t1_512`.`a1`) = `test`.`t2_512`.`b1`))))
select left(a1,7), left(a2,7)
from t1_512
where a1 in (select b1 from t2_512 where b1 > '0');
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
explain extended select left(a1,7), left(a2,7)
from t1_512
where (a1,a2) in (select b1, b2 from t2_512 where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_512 ALL NULL NULL NULL NULL 3 100.00 Using where
2 DEPENDENT SUBQUERY t2_512 ALL NULL NULL NULL NULL 3 100.00 Using where
Warnings:
Note 1003 select left(`test`.`t1_512`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_512`.`a2`,7) AS `left(a2,7)` from `test`.`t1_512` where <in_optimizer>((`test`.`t1_512`.`a1`,`test`.`t1_512`.`a2`),(`test`.`t1_512`.`a1`,`test`.`t1_512`.`a2`) in (select `test`.`t2_512`.`b1` AS `b1`,`test`.`t2_512`.`b2` AS `b2` from `test`.`t2_512` where ((`test`.`t2_512`.`b1` > '0') and (<cache>(`test`.`t1_512`.`a1`) = `test`.`t2_512`.`b1`) and (<cache>(`test`.`t1_512`.`a2`) = `test`.`t2_512`.`b2`))))
select left(a1,7), left(a2,7)
from t1_512
where (a1,a2) in (select b1, b2 from t2_512 where b1 > '0');
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
explain extended select left(a1,7), left(a2,7)
from t1_512
where a1 in (select substring(b1,1,512) from t2_512 where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_512 ALL NULL NULL NULL NULL 3 100.00 Using where
2 SUBQUERY t2_512 ALL NULL NULL NULL NULL 3 100.00 Using where
Warnings:
Note 1003 select left(`test`.`t1_512`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_512`.`a2`,7) AS `left(a2,7)` from `test`.`t1_512` where <in_optimizer>(`test`.`t1_512`.`a1`,`test`.`t1_512`.`a1` in ( <materialize> (select substr(`test`.`t2_512`.`b1`,1,512) AS `substring(b1,1,512)` from `test`.`t2_512` where (`test`.`t2_512`.`b1` > '0') ), <primary_index_lookup>(`test`.`t1_512`.`a1` in <temporary table> on distinct_key)))
select left(a1,7), left(a2,7)
from t1_512
where a1 in (select substring(b1,1,512) from t2_512 where b1 > '0');
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
explain extended select left(a1,7), left(a2,7)
from t1_512
where a1 in (select group_concat(b1) from t2_512 group by b2);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_512 ALL NULL NULL NULL NULL 3 100.00 Using where
2 SUBQUERY t2_512 ALL NULL NULL NULL NULL 3 100.00 Using filesort
Warnings:
Note 1003 select left(`test`.`t1_512`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_512`.`a2`,7) AS `left(a2,7)` from `test`.`t1_512` where <in_optimizer>(`test`.`t1_512`.`a1`,`test`.`t1_512`.`a1` in ( <materialize> (select group_concat(`test`.`t2_512`.`b1` separator ',') AS `group_concat(b1)` from `test`.`t2_512` group by `test`.`t2_512`.`b2` ), <primary_index_lookup>(`test`.`t1_512`.`a1` in <temporary table> on distinct_key)))
select left(a1,7), left(a2,7)
from t1_512
where a1 in (select group_concat(b1) from t2_512 group by b2);
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
set @@group_concat_max_len = 256;
explain extended select left(a1,7), left(a2,7)
from t1_512
where a1 in (select group_concat(b1) from t2_512 group by b2);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_512 ALL NULL NULL NULL NULL 3 100.00 Using where
2 SUBQUERY t2_512 ALL NULL NULL NULL NULL 3 100.00 Using filesort
Warnings:
Note 1003 select left(`test`.`t1_512`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_512`.`a2`,7) AS `left(a2,7)` from `test`.`t1_512` where <in_optimizer>(`test`.`t1_512`.`a1`,`test`.`t1_512`.`a1` in ( <materialize> (select group_concat(`test`.`t2_512`.`b1` separator ',') AS `group_concat(b1)` from `test`.`t2_512` group by `test`.`t2_512`.`b2` ), <primary_index_lookup>(`test`.`t1_512`.`a1` in <temporary table> on distinct_key)))
select left(a1,7), left(a2,7)
from t1_512
where a1 in (select group_concat(b1) from t2_512 group by b2);
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
drop table t1_512, t2_512, t3_512;
set @blob_len = 1024;
set @suffix_len = @blob_len - @prefix_len;
create temporary table t1_1024 (a1 blob, a2 blob) ENGINE=MyISAM;
create temporary table t2_1024 (b1 blob, b2 blob) ENGINE=MyISAM;
create temporary table t3_1024 (c1 blob, c2 blob) ENGINE=MyISAM;
insert into t1_1024 values
(concat('1 - 00', repeat('x', @suffix_len)), concat('2 - 00', repeat('x', @suffix_len)));
insert into t1_1024 values
(concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
insert into t1_1024 values
(concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
insert into t2_1024 values
(concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
insert into t2_1024 values
(concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
insert into t2_1024 values
(concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len)));
insert into t3_1024 values
(concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
insert into t3_1024 values
(concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
insert into t3_1024 values
(concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len)));
insert into t3_1024 values
(concat('1 - 04', repeat('x', @suffix_len)), concat('2 - 04', repeat('x', @suffix_len)));
explain extended select left(a1,7), left(a2,7)
from t1_1024
where a1 in (select b1 from t2_1024 where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_1024 ALL NULL NULL NULL NULL 3 100.00 Using where
2 DEPENDENT SUBQUERY t2_1024 ALL NULL NULL NULL NULL 3 100.00 Using where
Warnings:
Note 1003 select left(`test`.`t1_1024`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1024`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1024` where <in_optimizer>(`test`.`t1_1024`.`a1`,`test`.`t1_1024`.`a1` in (select 1 AS `Not_used` from `test`.`t2_1024` where ((`test`.`t2_1024`.`b1` > '0') and (<cache>(`test`.`t1_1024`.`a1`) = `test`.`t2_1024`.`b1`))))
select left(a1,7), left(a2,7)
from t1_1024
where a1 in (select b1 from t2_1024 where b1 > '0');
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
explain extended select left(a1,7), left(a2,7)
from t1_1024
where (a1,a2) in (select b1, b2 from t2_1024 where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_1024 ALL NULL NULL NULL NULL 3 100.00 Using where
2 DEPENDENT SUBQUERY t2_1024 ALL NULL NULL NULL NULL 3 100.00 Using where
Warnings:
Note 1003 select left(`test`.`t1_1024`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1024`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1024` where <in_optimizer>((`test`.`t1_1024`.`a1`,`test`.`t1_1024`.`a2`),(`test`.`t1_1024`.`a1`,`test`.`t1_1024`.`a2`) in (select `test`.`t2_1024`.`b1` AS `b1`,`test`.`t2_1024`.`b2` AS `b2` from `test`.`t2_1024` where ((`test`.`t2_1024`.`b1` > '0') and (<cache>(`test`.`t1_1024`.`a1`) = `test`.`t2_1024`.`b1`) and (<cache>(`test`.`t1_1024`.`a2`) = `test`.`t2_1024`.`b2`))))
select left(a1,7), left(a2,7)
from t1_1024
where (a1,a2) in (select b1, b2 from t2_1024 where b1 > '0');
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
explain extended select left(a1,7), left(a2,7)
from t1_1024
where a1 in (select substring(b1,1,1024) from t2_1024 where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_1024 ALL NULL NULL NULL NULL 3 100.00 Using where
2 DEPENDENT SUBQUERY t2_1024 ALL NULL NULL NULL NULL 3 100.00 Using where
Warnings:
Note 1003 select left(`test`.`t1_1024`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1024`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1024` where <in_optimizer>(`test`.`t1_1024`.`a1`,`test`.`t1_1024`.`a1` in (select 1 AS `Not_used` from `test`.`t2_1024` where ((`test`.`t2_1024`.`b1` > '0') and (<cache>(`test`.`t1_1024`.`a1`) = substr(`test`.`t2_1024`.`b1`,1,1024)))))
select left(a1,7), left(a2,7)
from t1_1024
where a1 in (select substring(b1,1,1024) from t2_1024 where b1 > '0');
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
explain extended select left(a1,7), left(a2,7)
from t1_1024
where a1 in (select group_concat(b1) from t2_1024 group by b2);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_1024 ALL NULL NULL NULL NULL 3 100.00 Using where
2 SUBQUERY t2_1024 ALL NULL NULL NULL NULL 3 100.00 Using filesort
Warnings:
Note 1003 select left(`test`.`t1_1024`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1024`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1024` where <in_optimizer>(`test`.`t1_1024`.`a1`,`test`.`t1_1024`.`a1` in ( <materialize> (select group_concat(`test`.`t2_1024`.`b1` separator ',') AS `group_concat(b1)` from `test`.`t2_1024` group by `test`.`t2_1024`.`b2` ), <primary_index_lookup>(`test`.`t1_1024`.`a1` in <temporary table> on distinct_key)))
select left(a1,7), left(a2,7)
from t1_1024
where a1 in (select group_concat(b1) from t2_1024 group by b2);
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
set @@group_concat_max_len = 256;
explain extended select left(a1,7), left(a2,7)
from t1_1024
where a1 in (select group_concat(b1) from t2_1024 group by b2);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_1024 ALL NULL NULL NULL NULL 3 100.00 Using where
2 SUBQUERY t2_1024 ALL NULL NULL NULL NULL 3 100.00 Using filesort
Warnings:
Note 1003 select left(`test`.`t1_1024`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1024`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1024` where <in_optimizer>(`test`.`t1_1024`.`a1`,`test`.`t1_1024`.`a1` in ( <materialize> (select group_concat(`test`.`t2_1024`.`b1` separator ',') AS `group_concat(b1)` from `test`.`t2_1024` group by `test`.`t2_1024`.`b2` ), <primary_index_lookup>(`test`.`t1_1024`.`a1` in <temporary table> on distinct_key)))
select left(a1,7), left(a2,7)
from t1_1024
where a1 in (select group_concat(b1) from t2_1024 group by b2);
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
drop table t1_1024, t2_1024, t3_1024;
set @blob_len = 1025;
set @suffix_len = @blob_len - @prefix_len;
create temporary table t1_1025 (a1 blob, a2 blob) ENGINE=MyISAM;
create temporary table t2_1025 (b1 blob, b2 blob) ENGINE=MyISAM;
create temporary table t3_1025 (c1 blob, c2 blob) ENGINE=MyISAM;
insert into t1_1025 values
(concat('1 - 00', repeat('x', @suffix_len)), concat('2 - 00', repeat('x', @suffix_len)));
insert into t1_1025 values
(concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
insert into t1_1025 values
(concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
insert into t2_1025 values
(concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
insert into t2_1025 values
(concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
insert into t2_1025 values
(concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len)));
insert into t3_1025 values
(concat('1 - 01', repeat('x', @suffix_len)), concat('2 - 01', repeat('x', @suffix_len)));
insert into t3_1025 values
(concat('1 - 02', repeat('x', @suffix_len)), concat('2 - 02', repeat('x', @suffix_len)));
insert into t3_1025 values
(concat('1 - 03', repeat('x', @suffix_len)), concat('2 - 03', repeat('x', @suffix_len)));
insert into t3_1025 values
(concat('1 - 04', repeat('x', @suffix_len)), concat('2 - 04', repeat('x', @suffix_len)));
explain extended select left(a1,7), left(a2,7)
from t1_1025
where a1 in (select b1 from t2_1025 where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_1025 ALL NULL NULL NULL NULL 3 100.00 Using where
2 DEPENDENT SUBQUERY t2_1025 ALL NULL NULL NULL NULL 3 100.00 Using where
Warnings:
Note 1003 select left(`test`.`t1_1025`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1025`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1025` where <in_optimizer>(`test`.`t1_1025`.`a1`,`test`.`t1_1025`.`a1` in (select 1 AS `Not_used` from `test`.`t2_1025` where ((`test`.`t2_1025`.`b1` > '0') and (<cache>(`test`.`t1_1025`.`a1`) = `test`.`t2_1025`.`b1`))))
select left(a1,7), left(a2,7)
from t1_1025
where a1 in (select b1 from t2_1025 where b1 > '0');
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
explain extended select left(a1,7), left(a2,7)
from t1_1025
where (a1,a2) in (select b1, b2 from t2_1025 where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_1025 ALL NULL NULL NULL NULL 3 100.00 Using where
2 DEPENDENT SUBQUERY t2_1025 ALL NULL NULL NULL NULL 3 100.00 Using where
Warnings:
Note 1003 select left(`test`.`t1_1025`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1025`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1025` where <in_optimizer>((`test`.`t1_1025`.`a1`,`test`.`t1_1025`.`a2`),(`test`.`t1_1025`.`a1`,`test`.`t1_1025`.`a2`) in (select `test`.`t2_1025`.`b1` AS `b1`,`test`.`t2_1025`.`b2` AS `b2` from `test`.`t2_1025` where ((`test`.`t2_1025`.`b1` > '0') and (<cache>(`test`.`t1_1025`.`a1`) = `test`.`t2_1025`.`b1`) and (<cache>(`test`.`t1_1025`.`a2`) = `test`.`t2_1025`.`b2`))))
select left(a1,7), left(a2,7)
from t1_1025
where (a1,a2) in (select b1, b2 from t2_1025 where b1 > '0');
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
explain extended select left(a1,7), left(a2,7)
from t1_1025
where a1 in (select substring(b1,1,1025) from t2_1025 where b1 > '0');
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_1025 ALL NULL NULL NULL NULL 3 100.00 Using where
2 DEPENDENT SUBQUERY t2_1025 ALL NULL NULL NULL NULL 3 100.00 Using where
Warnings:
Note 1003 select left(`test`.`t1_1025`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1025`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1025` where <in_optimizer>(`test`.`t1_1025`.`a1`,`test`.`t1_1025`.`a1` in (select 1 AS `Not_used` from `test`.`t2_1025` where ((`test`.`t2_1025`.`b1` > '0') and (<cache>(`test`.`t1_1025`.`a1`) = substr(`test`.`t2_1025`.`b1`,1,1025)))))
select left(a1,7), left(a2,7)
from t1_1025
where a1 in (select substring(b1,1,1025) from t2_1025 where b1 > '0');
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
explain extended select left(a1,7), left(a2,7)
from t1_1025
where a1 in (select group_concat(b1) from t2_1025 group by b2);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_1025 ALL NULL NULL NULL NULL 3 100.00 Using where
2 SUBQUERY t2_1025 ALL NULL NULL NULL NULL 3 100.00 Using filesort
Warnings:
Note 1003 select left(`test`.`t1_1025`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1025`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1025` where <in_optimizer>(`test`.`t1_1025`.`a1`,`test`.`t1_1025`.`a1` in ( <materialize> (select group_concat(`test`.`t2_1025`.`b1` separator ',') AS `group_concat(b1)` from `test`.`t2_1025` group by `test`.`t2_1025`.`b2` ), <primary_index_lookup>(`test`.`t1_1025`.`a1` in <temporary table> on distinct_key)))
select left(a1,7), left(a2,7)
from t1_1025
where a1 in (select group_concat(b1) from t2_1025 group by b2);
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
set @@group_concat_max_len = 256;
explain extended select left(a1,7), left(a2,7)
from t1_1025
where a1 in (select group_concat(b1) from t2_1025 group by b2);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1_1025 ALL NULL NULL NULL NULL 3 100.00 Using where
2 SUBQUERY t2_1025 ALL NULL NULL NULL NULL 3 100.00 Using filesort
Warnings:
Note 1003 select left(`test`.`t1_1025`.`a1`,7) AS `left(a1,7)`,left(`test`.`t1_1025`.`a2`,7) AS `left(a2,7)` from `test`.`t1_1025` where <in_optimizer>(`test`.`t1_1025`.`a1`,`test`.`t1_1025`.`a1` in ( <materialize> (select group_concat(`test`.`t2_1025`.`b1` separator ',') AS `group_concat(b1)` from `test`.`t2_1025` group by `test`.`t2_1025`.`b2` ), <primary_index_lookup>(`test`.`t1_1025`.`a1` in <temporary table> on distinct_key)))
select left(a1,7), left(a2,7)
from t1_1025
where a1 in (select group_concat(b1) from t2_1025 group by b2);
left(a1,7) left(a2,7)
1 - 01x 2 - 01x
1 - 02x 2 - 02x
drop table t1_1025, t2_1025, t3_1025;
drop table t1, t2, t3;
/******************************************************************************
* Test the cache of the left operand of IN.
******************************************************************************/
# Test that default values of Cached_item are not used for comparison
create temporary table t1 (s1 int) ENGINE=MyISAM;
create temporary table t2 (s2 int) ENGINE=MyISAM;
insert into t1 values (5),(1),(0);
insert into t2 values (0), (1);
select s2 from t2 where s2 in (select s1 from t1);
s2
0
1
drop table t1, t2;
create temporary table t1 (a int not null, b int not null) ENGINE=MyISAM;
create temporary table t2 (c int not null, d int not null) ENGINE=MyISAM;
create temporary table t3 (e int not null) ENGINE=MyISAM;
insert into t1 values (1,10);
insert into t1 values (1,20);
insert into t1 values (2,10);
insert into t1 values (2,20);
insert into t1 values (2,30);
insert into t1 values (3,20);
insert into t1 values (4,40);
insert into t2 values (2,10);
insert into t2 values (2,20);
insert into t2 values (2,40);
insert into t2 values (3,20);
insert into t2 values (4,10);
insert into t2 values (5,10);
insert into t3 values (10);
insert into t3 values (10);
insert into t3 values (20);
insert into t3 values (30);
explain extended
select a from t1 where a in (select c from t2 where d >= 20);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 7 100.00 Using where
2 SUBQUERY t2 ALL NULL NULL NULL NULL 6 100.00 Using where
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where <in_optimizer>(`test`.`t1`.`a`,`test`.`t1`.`a` in ( <materialize> (select `test`.`t2`.`c` AS `c` from `test`.`t2` where (`test`.`t2`.`d` >= 20) ), <primary_index_lookup>(`test`.`t1`.`a` in <temporary table> on distinct_key)))
select a from t1 where a in (select c from t2 where d >= 20);
a
2
2
2
3
create index it1a on t1(a);
explain extended
select a from t1 where a in (select c from t2 where d >= 20);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 index NULL it1a 4 NULL 7 100.00 Using where; Using index
2 SUBQUERY t2 ALL NULL NULL NULL NULL 6 100.00 Using where
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where <in_optimizer>(`test`.`t1`.`a`,`test`.`t1`.`a` in ( <materialize> (select `test`.`t2`.`c` AS `c` from `test`.`t2` where (`test`.`t2`.`d` >= 20) ), <primary_index_lookup>(`test`.`t1`.`a` in <temporary table> on distinct_key)))
select a from t1 where a in (select c from t2 where d >= 20);
a
2
2
2
3
insert into t2 values (1,10);
explain extended
select a from t1 where a in (select c from t2 where d >= 20);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 index NULL it1a 4 NULL 7 100.00 Using where; Using index
2 SUBQUERY t2 ALL NULL NULL NULL NULL 7 100.00 Using where
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where <in_optimizer>(`test`.`t1`.`a`,`test`.`t1`.`a` in ( <materialize> (select `test`.`t2`.`c` AS `c` from `test`.`t2` where (`test`.`t2`.`d` >= 20) ), <primary_index_lookup>(`test`.`t1`.`a` in <temporary table> on distinct_key)))
select a from t1 where a in (select c from t2 where d >= 20);
a
2
2
2
3
explain extended
select a from t1 group by a having a in (select c from t2 where d >= 20);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 index NULL it1a 4 NULL 7 100.00 Using index
2 SUBQUERY t2 ALL NULL NULL NULL NULL 7 100.00 Using where
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` group by `test`.`t1`.`a` having <in_optimizer>(`test`.`t1`.`a`,`test`.`t1`.`a` in ( <materialize> (select `test`.`t2`.`c` AS `c` from `test`.`t2` where (`test`.`t2`.`d` >= 20) ), <primary_index_lookup>(`test`.`t1`.`a` in <temporary table> on distinct_key)))
select a from t1 group by a having a in (select c from t2 where d >= 20);
a
2
3
create index iab on t1(a, b);
explain extended
select a from t1 group by a having a in (select c from t2 where d >= 20);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 index NULL it1a 4 NULL 7 100.00 Using index
2 SUBQUERY t2 ALL NULL NULL NULL NULL 7 100.00 Using where
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` group by `test`.`t1`.`a` having <in_optimizer>(`test`.`t1`.`a`,`test`.`t1`.`a` in ( <materialize> (select `test`.`t2`.`c` AS `c` from `test`.`t2` where (`test`.`t2`.`d` >= 20) ), <primary_index_lookup>(`test`.`t1`.`a` in <temporary table> on distinct_key)))
select a from t1 group by a having a in (select c from t2 where d >= 20);
a
2
3
explain extended
select a from t1 group by a
having a in (select c from t2 where d >= some(select e from t3 where max(b)=e));
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 index NULL iab 8 NULL 7 100.00 Using index
2 DEPENDENT SUBQUERY t2 ALL NULL NULL NULL NULL 7 100.00 Using where
3 DEPENDENT SUBQUERY t3 ALL NULL NULL NULL NULL 4 100.00 Using where
Warnings:
Note 1276 Field or reference 'test.t1.b' of SELECT #3 was resolved in SELECT #1
Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` group by `test`.`t1`.`a` having <in_optimizer>(`test`.`t1`.`a`,<exists>(select 1 AS `Not_used` from `test`.`t2` where (<nop>(<in_optimizer>(`test`.`t2`.`d`,<exists>(select `test`.`t3`.`e` AS `e` from `test`.`t3` where (max(`test`.`t1`.`b`) = `test`.`t3`.`e`) having (<cache>(`test`.`t2`.`d`) >= <ref_null_helper>(`test`.`t3`.`e`))))) and (<cache>(`test`.`t1`.`a`) = `test`.`t2`.`c`))))
select a from t1 group by a
having a in (select c from t2 where d >= some(select e from t3 where max(b)=e));
a
2
3
explain extended
select a from t1
where a in (select c from t2 where d >= some(select e from t3 where b=e));
id select_type table type possible_keys key key_len ref rows filtered Extra
1 PRIMARY t1 index NULL iab 8 NULL 7 100.00 Using where; Using index
2 DEPENDENT SUBQUERY t2 ALL NULL NULL NULL NULL 7 100.00 Using where
3 DEPENDENT SUBQUERY t3 ALL NULL NULL NULL NULL 4 100.00 Using where
Warnings:
Note 1276 Field or reference 'test.t1.b' of SELECT #3 was resolved in SELECT #1
Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where <in_optimizer>(`test`.`t1`.`a`,<exists>(select 1 AS `Not_used` from `test`.`t2` where (<nop>(<in_optimizer>(`test`.`t2`.`d`,<exists>(select 1 AS `Not_used` from `test`.`t3` where ((`test`.`t1`.`b` = `test`.`t3`.`e`) and (<cache>(`test`.`t2`.`d`) >= `test`.`t3`.`e`))))) and (<cache>(`test`.`t1`.`a`) = `test`.`t2`.`c`))))
select a from t1
where a in (select c from t2 where d >= some(select e from t3 where b=e));
a
1
2
2
2
3
drop table t1, t2, t3;
|