2011-11-02 10:48:41 +01:00
set @subselect_extra_no_sj_tmp=@@optimizer_switch;
2011-11-15 22:03:00 +01:00
set @optimizer_switch_for_subselect_extra_test='semijoin=off,firstmatch=off,loosescan=off,semijoin_with_cache=off';
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drop table if exists t1,t2,t3,t4;
drop view if exists v1,v2,v3;
2011-11-15 22:03:00 +01:00
set @subselect_extra_tmp=@@optimizer_switch;
set @@optimizer_switch=ifnull(@optimizer_switch_for_subselect_extra_test,
"semijoin=on,firstmatch=on,loosescan=on,semijoin_with_cache=on,partial_match_rowid_merge=off,partial_match_table_scan=off");
2011-11-02 10:48:41 +01:00
# 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
2011-11-07 13:39:02 +01:00
1 PRIMARY OUTR ALL NULL NULL NULL NULL 2 Using where
2 DEPENDENT SUBQUERY INNR ALL NULL NULL NULL NULL 2 Using where
2011-11-02 10:48:41 +01:00
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
2011-11-07 13:39:02 +01:00
1 PRIMARY OUTR ALL NULL NULL NULL NULL 2 Using where
2 DEPENDENT SUBQUERY INNR ALL NULL NULL NULL NULL 2 Using where
2011-11-02 10:48:41 +01:00
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
2011-11-07 13:39:02 +01:00
1 PRIMARY t1 system NULL NULL NULL NULL 1 100.00
Patch for mdev-287: CHEAP SQ: A query with subquery in SELECT list, EXISTS, inner joins takes hundreds times longer
Analysis:
The fix for lp:944706 introduces early subquery optimization.
While a subquery is being optimized some of its predicates may be
removed. In the test case, the EXISTS subquery is constant, and is
evaluated to TRUE. As a result the whole OR is TRUE, and thus the
correlated condition "b = alias1.b" is optimized away. The subquery
becomes non-correlated.
The subquery cache is designed to work only for correlated subqueries.
If constant subquery optimization is disallowed, then the constant
subquery is not evaluated, the subquery remains correlated, and its
execution is cached. As a result execution is fast.
However, when the constant subquery was optimized away, it was neither
cached by the subquery cache, nor it was cached by the internal subquery
caching. The latter was due to the fact that the subquery still appeared
as correlated to the subselect_XYZ_engine::exec methods, and they
re-executed the subquery on each call to Item_subselect::exec.
Solution:
The solution is to update the correlated status of the subquery after it has
been optimized. This status consists of:
- st_select_lex::is_correlated
- Item_subselect::is_correlated
- SELECT_LEX::uncacheable
- SELECT_LEX_UNIT::uncacheable
The status is updated by st_select_lex::update_correlated_cache(), and its
caller st_select_lex::optimize_unflattened_subqueries. The solution relies
on the fact that the optimizer already called
st_select_lex::update_used_tables() for each subquery. This allows to
efficiently update the correlated status of each subquery without walking
the whole subquery tree.
Notice that his patch is an improvement over MySQL 5.6 and older, where
subqueries are not pre-optimized, and the above analysis is not possible.
2012-05-29 23:18:53 +02:00
2 SUBQUERY NULL NULL NULL NULL NULL NULL NULL NULL Impossible WHERE
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Warnings:
Note 1276 Field or reference 'test.t1.cur_date' of SELECT #2 was resolved in SELECT #1
2017-01-22 12:31:32 +01:00
Note 1003 /* select#1 */ select 1 AS `id`,'2007-04-25 18:30:22' AS `cur_date` from dual where <expr_cache><1>(<in_optimizer>(1,<exists>(/* select#2 */ select `test`.`x1`.`id` from `test`.`t1` `x1` where 0)))
2011-11-02 10:48:41 +01:00
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
2011-11-07 13:39:02 +01:00
1 PRIMARY t2 system NULL NULL NULL NULL 1 100.00
Patch for mdev-287: CHEAP SQ: A query with subquery in SELECT list, EXISTS, inner joins takes hundreds times longer
Analysis:
The fix for lp:944706 introduces early subquery optimization.
While a subquery is being optimized some of its predicates may be
removed. In the test case, the EXISTS subquery is constant, and is
evaluated to TRUE. As a result the whole OR is TRUE, and thus the
correlated condition "b = alias1.b" is optimized away. The subquery
becomes non-correlated.
The subquery cache is designed to work only for correlated subqueries.
If constant subquery optimization is disallowed, then the constant
subquery is not evaluated, the subquery remains correlated, and its
execution is cached. As a result execution is fast.
However, when the constant subquery was optimized away, it was neither
cached by the subquery cache, nor it was cached by the internal subquery
caching. The latter was due to the fact that the subquery still appeared
as correlated to the subselect_XYZ_engine::exec methods, and they
re-executed the subquery on each call to Item_subselect::exec.
Solution:
The solution is to update the correlated status of the subquery after it has
been optimized. This status consists of:
- st_select_lex::is_correlated
- Item_subselect::is_correlated
- SELECT_LEX::uncacheable
- SELECT_LEX_UNIT::uncacheable
The status is updated by st_select_lex::update_correlated_cache(), and its
caller st_select_lex::optimize_unflattened_subqueries. The solution relies
on the fact that the optimizer already called
st_select_lex::update_used_tables() for each subquery. This allows to
efficiently update the correlated status of each subquery without walking
the whole subquery tree.
Notice that his patch is an improvement over MySQL 5.6 and older, where
subqueries are not pre-optimized, and the above analysis is not possible.
2012-05-29 23:18:53 +02:00
2 SUBQUERY NULL NULL NULL NULL NULL NULL NULL NULL Impossible WHERE
2011-11-02 10:48:41 +01:00
Warnings:
Note 1276 Field or reference 'test.t2.cur_date' of SELECT #2 was resolved in SELECT #1
2017-01-22 12:31:32 +01:00
Note 1003 /* select#1 */ select 1 AS `id`,'2007-04-25' AS `cur_date` from dual where <expr_cache><1>(<in_optimizer>(1,<exists>(/* select#2 */ select `test`.`x1`.`id` from `test`.`t2` `x1` where 0)))
2011-11-02 10:48:41 +01:00
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
2011-11-07 13:39:02 +01:00
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
2011-11-02 10:48:41 +01:00
Warnings:
Note 1276 Field or reference 'test.t1.cur_date' of SELECT #2 was resolved in SELECT #1
2017-01-22 12:31:32 +01:00
Note 1003 /* select#1 */ 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#2 */ select `test`.`x1`.`id` from `test`.`t1` `x1` where `test`.`t1`.`cur_date` = 0 and <cache>(`test`.`t1`.`id`) = `test`.`x1`.`id`)))
2011-11-02 10:48:41 +01:00
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
2011-11-07 13:39:02 +01:00
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
2011-11-02 10:48:41 +01:00
Warnings:
Note 1276 Field or reference 'test.t2.cur_date' of SELECT #2 was resolved in SELECT #1
2017-01-22 12:31:32 +01:00
Note 1003 /* select#1 */ 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#2 */ select `test`.`x1`.`id` from `test`.`t2` `x1` where `test`.`t2`.`cur_date` = 0 and <cache>(`test`.`t2`.`id`) = `test`.`x1`.`id`)))
2011-11-02 10:48:41 +01:00
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 ' '
);
insert into t1 (a1, a2, b, c, d) values
('a','a','a','a111','xy1'),('a','a','a','b111','xy2'),('a','a','a','c111','xy3'),('a','a','a','d111','xy4'),
('a','a','b','e112','xy1'),('a','a','b','f112','xy2'),('a','a','b','g112','xy3'),('a','a','b','h112','xy4'),
('a','b','a','i121','xy1'),('a','b','a','j121','xy2'),('a','b','a','k121','xy3'),('a','b','a','l121','xy4'),
('a','b','b','m122','xy1'),('a','b','b','n122','xy2'),('a','b','b','o122','xy3'),('a','b','b','p122','xy4'),
('b','a','a','a211','xy1'),('b','a','a','b211','xy2'),('b','a','a','c211','xy3'),('b','a','a','d211','xy4'),
('b','a','b','e212','xy1'),('b','a','b','f212','xy2'),('b','a','b','g212','xy3'),('b','a','b','h212','xy4'),
('b','b','a','i221','xy1'),('b','b','a','j221','xy2'),('b','b','a','k221','xy3'),('b','b','a','l221','xy4'),
('b','b','b','m222','xy1'),('b','b','b','n222','xy2'),('b','b','b','o222','xy3'),('b','b','b','p222','xy4'),
('c','a','a','a311','xy1'),('c','a','a','b311','xy2'),('c','a','a','c311','xy3'),('c','a','a','d311','xy4'),
('c','a','b','e312','xy1'),('c','a','b','f312','xy2'),('c','a','b','g312','xy3'),('c','a','b','h312','xy4'),
('c','b','a','i321','xy1'),('c','b','a','j321','xy2'),('c','b','a','k321','xy3'),('c','b','a','l321','xy4'),
('c','b','b','m322','xy1'),('c','b','b','n322','xy2'),('c','b','b','o322','xy3'),('c','b','b','p322','xy4'),
('d','a','a','a411','xy1'),('d','a','a','b411','xy2'),('d','a','a','c411','xy3'),('d','a','a','d411','xy4'),
('d','a','b','e412','xy1'),('d','a','b','f412','xy2'),('d','a','b','g412','xy3'),('d','a','b','h412','xy4'),
('d','b','a','i421','xy1'),('d','b','a','j421','xy2'),('d','b','a','k421','xy3'),('d','b','a','l421','xy4'),
('d','b','b','m422','xy1'),('d','b','b','n422','xy2'),('d','b','b','o422','xy3'),('d','b','b','p422','xy4'),
('a','a','a','a111','xy1'),('a','a','a','b111','xy2'),('a','a','a','c111','xy3'),('a','a','a','d111','xy4'),
('a','a','b','e112','xy1'),('a','a','b','f112','xy2'),('a','a','b','g112','xy3'),('a','a','b','h112','xy4'),
('a','b','a','i121','xy1'),('a','b','a','j121','xy2'),('a','b','a','k121','xy3'),('a','b','a','l121','xy4'),
('a','b','b','m122','xy1'),('a','b','b','n122','xy2'),('a','b','b','o122','xy3'),('a','b','b','p122','xy4'),
('b','a','a','a211','xy1'),('b','a','a','b211','xy2'),('b','a','a','c211','xy3'),('b','a','a','d211','xy4'),
('b','a','b','e212','xy1'),('b','a','b','f212','xy2'),('b','a','b','g212','xy3'),('b','a','b','h212','xy4'),
('b','b','a','i221','xy1'),('b','b','a','j221','xy2'),('b','b','a','k221','xy3'),('b','b','a','l221','xy4'),
('b','b','b','m222','xy1'),('b','b','b','n222','xy2'),('b','b','b','o222','xy3'),('b','b','b','p222','xy4'),
('c','a','a','a311','xy1'),('c','a','a','b311','xy2'),('c','a','a','c311','xy3'),('c','a','a','d311','xy4'),
('c','a','b','e312','xy1'),('c','a','b','f312','xy2'),('c','a','b','g312','xy3'),('c','a','b','h312','xy4'),
('c','b','a','i321','xy1'),('c','b','a','j321','xy2'),('c','b','a','k321','xy3'),('c','b','a','l321','xy4'),
('c','b','b','m322','xy1'),('c','b','b','n322','xy2'),('c','b','b','o322','xy3'),('c','b','b','p322','xy4'),
('d','a','a','a411','xy1'),('d','a','a','b411','xy2'),('d','a','a','c411','xy3'),('d','a','a','d411','xy4'),
('d','a','b','e412','xy1'),('d','a','b','f412','xy2'),('d','a','b','g412','xy3'),('d','a','b','h412','xy4'),
('d','b','a','i421','xy1'),('d','b','a','j421','xy2'),('d','b','a','k421','xy3'),('d','b','a','l421','xy4'),
('d','b','b','m422','xy1'),('d','b','b','n422','xy2'),('d','b','b','o422','xy3'),('d','b','b','p422','xy4');
create index idx_t1_0 on t1 (a1);
create index idx_t1_1 on t1 (a1,a2,b,c);
create index idx_t1_2 on t1 (a1,a2,b);
analyze table t1;
Table Op Msg_type Msg_text
2018-05-31 12:21:59 +02:00
test.t1 analyze status Engine-independent statistics collected
2011-11-02 10:48:41 +01:00
test.t1 analyze status Table is already up to date
create table t2 (
a1 char(64), a2 char(64) not null, b char(16), c char(16), d char(16), dummy char(64) default ' '
);
insert into t2 select * from t1;
insert into t2 (a1, a2, b, c, d) values
('a','a',NULL,'a777','xyz'),('a','a',NULL,'a888','xyz'),('a','a',NULL,'a999','xyz'),
('a','a','a',NULL,'xyz'),
('a','a','b',NULL,'xyz'),
('a','b','a',NULL,'xyz'),
('c','a',NULL,'c777','xyz'),('c','a',NULL,'c888','xyz'),('c','a',NULL,'c999','xyz'),
('d','b','b',NULL,'xyz'),
('e','a','a',NULL,'xyz'),('e','a','a',NULL,'xyz'),('e','a','a',NULL,'xyz'),('e','a','a',NULL,'xyz'),
('e','a','b',NULL,'xyz'),('e','a','b',NULL,'xyz'),('e','a','b',NULL,'xyz'),('e','a','b',NULL,'xyz'),
('a','a',NULL,'a777','xyz'),('a','a',NULL,'a888','xyz'),('a','a',NULL,'a999','xyz'),
('a','a','a',NULL,'xyz'),
('a','a','b',NULL,'xyz'),
('a','b','a',NULL,'xyz'),
('c','a',NULL,'c777','xyz'),('c','a',NULL,'c888','xyz'),('c','a',NULL,'c999','xyz'),
('d','b','b',NULL,'xyz'),
('e','a','a',NULL,'xyz'),('e','a','a',NULL,'xyz'),('e','a','a',NULL,'xyz'),('e','a','a',NULL,'xyz'),
('e','a','b',NULL,'xyz'),('e','a','b',NULL,'xyz'),('e','a','b',NULL,'xyz'),('e','a','b',NULL,'xyz');
create index idx_t2_0 on t2 (a1);
create index idx_t2_1 on t2 (a1,a2,b,c);
create index idx_t2_2 on t2 (a1,a2,b);
analyze table t2;
Table Op Msg_type Msg_text
2018-05-31 12:21:59 +02:00
test.t2 analyze status Engine-independent statistics collected
2011-11-02 10:48:41 +01:00
test.t2 analyze status Table is already up to date
create table t3 (
a1 char(1), a2 char(1), b char(1), c char(4) not null, d char(3), dummy char(1) default ' '
);
insert into t3 (a1, a2, b, c, d) values
('a','a','a','a111','xy1'),('a','a','a','b111','xy2'),('a','a','a','c111','xy3'),('a','a','a','d111','xy4'),
('a','a','b','e112','xy1'),('a','a','b','f112','xy2'),('a','a','b','g112','xy3'),('a','a','b','h112','xy4'),
('a','b','a','i121','xy1'),('a','b','a','j121','xy2'),('a','b','a','k121','xy3'),('a','b','a','l121','xy4'),
('a','b','b','m122','xy1'),('a','b','b','n122','xy2'),('a','b','b','o122','xy3'),('a','b','b','p122','xy4'),
('b','a','a','a211','xy1'),('b','a','a','b211','xy2'),('b','a','a','c211','xy3'),('b','a','a','d211','xy4'),
('b','a','b','e212','xy1'),('b','a','b','f212','xy2'),('b','a','b','g212','xy3'),('b','a','b','h212','xy4'),
('b','b','a','i221','xy1'),('b','b','a','j221','xy2'),('b','b','a','k221','xy3'),('b','b','a','l221','xy4'),
('b','b','b','m222','xy1'),('b','b','b','n222','xy2'),('b','b','b','o222','xy3'),('b','b','b','p222','xy4'),
('c','a','a','a311','xy1'),('c','a','a','b311','xy2'),('c','a','a','c311','xy3'),('c','a','a','d311','xy4'),
('c','a','b','e312','xy1'),('c','a','b','f312','xy2'),('c','a','b','g312','xy3'),('c','a','b','h312','xy4'),
('c','b','a','i321','xy1'),('c','b','a','j321','xy2'),('c','b','a','k321','xy3'),('c','b','a','l321','xy4'),
('c','b','b','m322','xy1'),('c','b','b','n322','xy2'),('c','b','b','o322','xy3'),('c','b','b','p322','xy4');
insert into t3 (a1, a2, b, c, d) values
('a','a','a','a111','xy1'),('a','a','a','b111','xy2'),('a','a','a','c111','xy3'),('a','a','a','d111','xy4'),
('a','a','b','e112','xy1'),('a','a','b','f112','xy2'),('a','a','b','g112','xy3'),('a','a','b','h112','xy4'),
('a','b','a','i121','xy1'),('a','b','a','j121','xy2'),('a','b','a','k121','xy3'),('a','b','a','l121','xy4'),
('a','b','b','m122','xy1'),('a','b','b','n122','xy2'),('a','b','b','o122','xy3'),('a','b','b','p122','xy4'),
('b','a','a','a211','xy1'),('b','a','a','b211','xy2'),('b','a','a','c211','xy3'),('b','a','a','d211','xy4'),
('b','a','b','e212','xy1'),('b','a','b','f212','xy2'),('b','a','b','g212','xy3'),('b','a','b','h212','xy4'),
('b','b','a','i221','xy1'),('b','b','a','j221','xy2'),('b','b','a','k221','xy3'),('b','b','a','l221','xy4'),
('b','b','b','m222','xy1'),('b','b','b','n222','xy2'),('b','b','b','o222','xy3'),('b','b','b','p222','xy4'),
('c','a','a','a311','xy1'),('c','a','a','b311','xy2'),('c','a','a','c311','xy3'),('c','a','a','d311','xy4'),
('c','a','b','e312','xy1'),('c','a','b','f312','xy2'),('c','a','b','g312','xy3'),('c','a','b','h312','xy4'),
('c','b','a','i321','xy1'),('c','b','a','j321','xy2'),('c','b','a','k321','xy3'),('c','b','a','l321','xy4'),
('c','b','b','m322','xy1'),('c','b','b','n322','xy2'),('c','b','b','o322','xy3'),('c','b','b','p322','xy4');
insert into t3 (a1, a2, b, c, d) values
('a','a','a','a111','xy1'),('a','a','a','b111','xy2'),('a','a','a','c111','xy3'),('a','a','a','d111','xy4'),
('a','a','b','e112','xy1'),('a','a','b','f112','xy2'),('a','a','b','g112','xy3'),('a','a','b','h112','xy4'),
('a','b','a','i121','xy1'),('a','b','a','j121','xy2'),('a','b','a','k121','xy3'),('a','b','a','l121','xy4'),
('a','b','b','m122','xy1'),('a','b','b','n122','xy2'),('a','b','b','o122','xy3'),('a','b','b','p122','xy4'),
('b','a','a','a211','xy1'),('b','a','a','b211','xy2'),('b','a','a','c211','xy3'),('b','a','a','d211','xy4'),
('b','a','b','e212','xy1'),('b','a','b','f212','xy2'),('b','a','b','g212','xy3'),('b','a','b','h212','xy4'),
('b','b','a','i221','xy1'),('b','b','a','j221','xy2'),('b','b','a','k221','xy3'),('b','b','a','l221','xy4'),
('b','b','b','m222','xy1'),('b','b','b','n222','xy2'),('b','b','b','o222','xy3'),('b','b','b','p222','xy4'),
('c','a','a','a311','xy1'),('c','a','a','b311','xy2'),('c','a','a','c311','xy3'),('c','a','a','d311','xy4'),
('c','a','b','e312','xy1'),('c','a','b','f312','xy2'),('c','a','b','g312','xy3'),('c','a','b','h312','xy4'),
('c','b','a','i321','xy1'),('c','b','a','j321','xy2'),('c','b','a','k321','xy3'),('c','b','a','l321','xy4'),
('c','b','b','m322','xy1'),('c','b','b','n322','xy2'),('c','b','b','o322','xy3'),('c','b','b','p322','xy4');
insert into t3 (a1, a2, b, c, d) values
('a','a','a','a111','xy1'),('a','a','a','b111','xy2'),('a','a','a','c111','xy3'),('a','a','a','d111','xy4'),
('a','a','b','e112','xy1'),('a','a','b','f112','xy2'),('a','a','b','g112','xy3'),('a','a','b','h112','xy4'),
('a','b','a','i121','xy1'),('a','b','a','j121','xy2'),('a','b','a','k121','xy3'),('a','b','a','l121','xy4'),
('a','b','b','m122','xy1'),('a','b','b','n122','xy2'),('a','b','b','o122','xy3'),('a','b','b','p122','xy4'),
('b','a','a','a211','xy1'),('b','a','a','b211','xy2'),('b','a','a','c211','xy3'),('b','a','a','d211','xy4'),
('b','a','b','e212','xy1'),('b','a','b','f212','xy2'),('b','a','b','g212','xy3'),('b','a','b','h212','xy4'),
('b','b','a','i221','xy1'),('b','b','a','j221','xy2'),('b','b','a','k221','xy3'),('b','b','a','l221','xy4'),
('b','b','b','m222','xy1'),('b','b','b','n222','xy2'),('b','b','b','o222','xy3'),('b','b','b','p222','xy4'),
('c','a','a','a311','xy1'),('c','a','a','b311','xy2'),('c','a','a','c311','xy3'),('c','a','a','d311','xy4'),
('c','a','b','e312','xy1'),('c','a','b','f312','xy2'),('c','a','b','g312','xy3'),('c','a','b','h312','xy4'),
('c','b','a','i321','xy1'),('c','b','a','j321','xy2'),('c','b','a','k321','xy3'),('c','b','a','l321','xy4'),
('c','b','b','m322','xy1'),('c','b','b','n322','xy2'),('c','b','b','o322','xy3'),('c','b','b','p322','xy4');
create index idx_t3_0 on t3 (a1);
create index idx_t3_1 on t3 (a1,a2,b,c);
create index idx_t3_2 on t3 (a1,a2,b);
analyze table t3;
Table Op Msg_type Msg_text
2018-05-31 12:21:59 +02:00
test.t3 analyze status Engine-independent statistics collected
2011-11-02 10:48:41 +01:00
test.t3 analyze status Table is already up to date
explain select a1,a2,b,c,min(c), max(c) from t1
where exists ( select * from t2
where t2.c in (select c from t3 where t3.c > t1.b) and
t2.c > 'b1' )
group by a1,a2,b;
id select_type table type possible_keys key key_len ref rows Extra
2014-06-09 12:42:21 +02:00
1 PRIMARY t1 index NULL idx_t1_1 163 NULL 128 Using where; Using index
2011-11-02 10:48:41 +01:00
2 DEPENDENT SUBQUERY t2 index NULL idx_t2_1 163 NULL 164 Using where; Using index
2011-11-07 13:39:02 +01:00
3 DEPENDENT SUBQUERY t3 index NULL idx_t3_1 10 NULL 192 Using where; Using index
2011-11-02 10:48:41 +01:00
select a1,a2,b,c,min(c), max(c) from t1
where exists ( select * from t2
where t2.c in (select c from t3 where t3.c > t1.b) and
t2.c > 'b1' )
group by a1,a2,b;
a1 a2 b c min(c) max(c)
2014-06-09 12:42:21 +02:00
a a a a111 a111 d111
a a b e112 e112 h112
a b a i121 i121 l121
a b b m122 m122 p122
b a a a211 a211 d211
b a b e212 e212 h212
b b a i221 i221 l221
b b b m222 m222 p222
c a a a311 a311 d311
c a b e312 e312 h312
c b a i321 i321 l321
c b b m322 m322 p322
d a a a411 a411 d411
d a b e412 e412 h412
d b a i421 i421 l421
d b b m422 m422 p422
2011-11-02 10:48:41 +01:00
explain select a1,a2,b,c,min(c), max(c) from t1
where exists ( select * from t2
where t2.c in (select c from t3 where t3.c > t1.c) and
t2.c > 'b1' )
group by a1,a2,b;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 index NULL idx_t1_1 163 NULL 128 Using where; Using index
2 DEPENDENT SUBQUERY t2 index NULL idx_t2_1 163 NULL 164 Using where; Using index
2011-11-07 13:39:02 +01:00
3 DEPENDENT SUBQUERY t3 index NULL idx_t3_1 10 NULL 192 Using where; Using index
2011-11-02 10:48:41 +01:00
select a1,a2,b,c,min(c), max(c) from t1
where exists ( select * from t2
where t2.c in (select c from t3 where t3.c > t1.c) and
t2.c > 'b1' )
group by a1,a2,b;
a1 a2 b c min(c) max(c)
a a a a111 a111 d111
a a b e112 e112 h112
a b a i121 i121 l121
a b b m122 m122 p122
b a a a211 a211 d211
b a b e212 e212 h212
b b a i221 i221 l221
b b b m222 m222 p222
c a a a311 a311 d311
c a b e312 e312 h312
c b a i321 i321 l321
c b b m322 m322 o322
d a a a411 a411 d411
d a b e412 e412 h412
d b a i421 i421 l421
d b b m422 m422 o422
drop table t1, t2, t3;
#
# From group_by.test
#
# Bug #21174: Index degrades sort performance and
# optimizer does not honor IGNORE INDEX.
# a.k.a WL3527.
#
CREATE TABLE t1 (a INT, b INT,
PRIMARY KEY (a),
KEY i2(a,b));
INSERT INTO t1 VALUES (1,1),(2,2),(3,3),(4,4),(5,5),(6,6),(7,7),(8,8);
INSERT INTO t1 SELECT a + 8,b FROM t1;
INSERT INTO t1 SELECT a + 16,b FROM t1;
INSERT INTO t1 SELECT a + 32,b FROM t1;
INSERT INTO t1 SELECT a + 64,b FROM t1;
INSERT INTO t1 SELECT a + 128,b FROM t1 limit 16;
ANALYZE TABLE t1;
Table Op Msg_type Msg_text
2018-05-31 12:21:59 +02:00
test.t1 analyze status Engine-independent statistics collected
2011-11-02 10:48:41 +01:00
test.t1 analyze status OK
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
2011-11-07 13:39:02 +01:00
1 PRIMARY t1 index NULL PRIMARY 4 NULL 144 Using where; Using index
2011-12-04 22:31:42 +01:00
2 MATERIALIZED t1 ALL NULL NULL NULL NULL 144
2011-11-02 10:48:41 +01:00
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;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 index NULL a 5 NULL 2
EXPLAIN SELECT a, SUM(b) FROM t2 IGNORE INDEX (a) GROUP BY a LIMIT 2;
id select_type table type possible_keys key key_len ref rows Extra
1 SIMPLE t2 ALL NULL NULL NULL NULL 4 Using temporary; Using filesort
EXPLAIN SELECT 1 FROM t2 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
2011-11-07 13:39:02 +01:00
1 PRIMARY t2 index NULL a 5 NULL 4 Using where; Using index
2011-12-04 22:31:42 +01:00
2 MATERIALIZED t1 ALL NULL NULL NULL NULL 144
2011-11-02 10:48:41 +01:00
DROP TABLE t1, t2;
#
# From derived_view.test
#
set @tmp_subselect_extra_derived=@@optimizer_switch;
set optimizer_switch='derived_merge=on,derived_with_keys=on';
#
# LP bug #806504: right join over a view/derived table
#
CREATE TABLE t1 (a int, b int) ;
INSERT INTO t1 VALUES (0,0);
CREATE TABLE t2 (a int) ;
INSERT INTO t2 VALUES (0), (0);
CREATE VIEW v1 AS SELECT * FROM t1;
SELECT * FROM t2 RIGHT JOIN (SELECT * FROM t1) AS t ON t.a != 0
WHERE t.a IN (SELECT b FROM t1);
a a b
NULL 0 0
EXPLAIN EXTENDED
SELECT * FROM t2 RIGHT JOIN (SELECT * FROM t1) 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 t2 ALL NULL NULL NULL NULL 2 100.00 Using where
2016-02-08 23:46:53 +01:00
3 DEPENDENT SUBQUERY t1 system NULL NULL NULL NULL 1 100.00
2011-11-02 10:48:41 +01:00
Warnings:
2017-01-22 12:31:32 +01:00
Note 1003 /* select#1 */ select `test`.`t2`.`a` AS `a`,0 AS `a`,0 AS `b` from `test`.`t2` where <expr_cache><0>(<in_optimizer>(0,<exists>(/* select#3 */ select 0 from dual where <cache>(0) = 0)))
2011-11-02 10:48:41 +01:00
SELECT * FROM t2 RIGHT JOIN v1 AS t ON t.a != 0
WHERE t.a IN (SELECT b FROM t1);
a a b
NULL 0 0
EXPLAIN EXTENDED
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 t2 ALL NULL NULL NULL NULL 2 100.00 Using where
2016-02-08 23:46:53 +01:00
2 DEPENDENT SUBQUERY t1 system NULL NULL NULL NULL 1 100.00
2011-11-02 10:48:41 +01:00
Warnings:
2017-01-22 12:31:32 +01:00
Note 1003 /* select#1 */ select `test`.`t2`.`a` AS `a`,0 AS `a`,0 AS `b` from `test`.`t2` where <expr_cache><0>(<in_optimizer>(0,<exists>(/* select#2 */ select 0 from dual where <cache>(0) = 0)))
2011-11-02 10:48:41 +01:00
DROP VIEW v1;
DROP TABLE t1,t2;
#
# LP bug #793448: materialized view accessed by two-component key
#
CREATE TABLE t1 (a int, b int);
INSERT INTO t1 VALUES (9,3), (2,5);
CREATE TABLE t2 (a int, b int);
INSERT INTO t2 VALUES (9,3), (3,7), (9,1), (2,5), (2,4), (3,8);
CREATE TABLE t3 (a int, b int);
INSERT INTO t3 VALUES (10,3), (9,7), (9,1), (2,4);
CREATE VIEW v1(a,b) AS SELECT a, MAX(b) FROM t2 GROUP BY a;
CREATE VIEW v2(a,b) AS SELECT a,b FROM t2 UNION SELECT a,b FROM t3;
SELECT * FROM v1;
a b
2 5
3 8
9 3
SELECT a FROM t1 WHERE (a,b) IN (SELECT * FROM v1);
a
9
2
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
2011-11-07 13:39:02 +01:00
2 DEPENDENT SUBQUERY <derived3> index_subquery key0 key0 10 func,func 2 Using where
2011-11-02 10:48:41 +01:00
3 DERIVED t2 ALL NULL NULL NULL NULL 6 Using temporary; Using filesort
SELECT * FROM v2;
a b
9 3
3 7
9 1
2 5
2 4
3 8
10 3
9 7
SELECT a FROM t1 WHERE (a,b) IN (SELECT * FROM v2);
a
9
2
EXPLAIN
SELECT a FROM t1 WHERE (a,b) IN (SELECT * FROM v2);
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 2 Using where
2019-04-30 17:35:50 +02:00
2 DEPENDENT SUBQUERY <derived3> index_subquery key0 key0 10 func,func 1 Using where
2011-11-02 10:48:41 +01:00
3 DERIVED t2 ALL NULL NULL NULL NULL 6
4 UNION t3 ALL NULL NULL NULL NULL 4
NULL UNION RESULT <union3,4> ALL NULL NULL NULL NULL NULL
DROP VIEW v1,v2;
DROP TABLE t1,t2,t3;
#
# LP bug #874006: materialized view used in IN subquery
#
CREATE TABLE t3 (a int NOT NULL, b varchar(1), c varchar(1));
INSERT INTO t3 VALUES (19,NULL,NULL), (20,'r','r');
CREATE TABLE t1 (a int, b varchar(1) , c varchar(1));
INSERT INTO t1 VALUES (1,NULL,NULL), (5,'r','r'), (7,'y','y');
CREATE TABLE t2 (a int NOT NULL , b int, c varchar(1));
INSERT INTO t2 VALUES (4,3,'r');
CREATE ALGORITHM=TEMPTABLE VIEW v1 AS SELECT * FROM t1;
SET SESSION optimizer_switch='derived_with_keys=off';
EXPLAIN
SELECT * FROM t3
WHERE t3.b IN (SELECT v1.b FROM v1, t2
WHERE t2.c = v1.c AND t2.c = v1.b AND v1.b = t3.c);
id select_type table type possible_keys key key_len ref rows Extra
2011-11-07 13:39:02 +01:00
1 PRIMARY t3 ALL NULL NULL NULL NULL 2 Using where
2 DEPENDENT SUBQUERY t2 system NULL NULL NULL NULL 1
2 DEPENDENT SUBQUERY <derived3> ALL NULL NULL NULL NULL 3 Using where
2016-09-05 05:11:58 +02:00
3 DERIVED t1 ALL NULL NULL NULL NULL 3 Using where
2011-11-02 10:48:41 +01:00
SELECT * FROM t3
WHERE t3.b IN (SELECT v1.b FROM v1, t2
WHERE t2.c = v1.c AND t2.c = v1.b AND v1.b = t3.c);
a b c
20 r r
SET SESSION optimizer_switch='derived_with_keys=on';
EXPLAIN
SELECT * FROM t3
WHERE t3.b IN (SELECT v1.b FROM v1, t2
WHERE t2.c = v1.c AND t2.c = v1.b AND v1.b = t3.c);
id select_type table type possible_keys key key_len ref rows Extra
2011-11-07 13:39:02 +01:00
1 PRIMARY t3 ALL NULL NULL NULL NULL 2 Using where
2 DEPENDENT SUBQUERY t2 system NULL NULL NULL NULL 1
2015-03-06 17:03:46 +01:00
2 DEPENDENT SUBQUERY <derived3> ref key1 key1 8 const,const 0 Using where
2016-09-05 05:11:58 +02:00
3 DERIVED t1 ALL NULL NULL NULL NULL 3 Using where
2011-11-02 10:48:41 +01:00
SELECT * FROM t3
WHERE t3.b IN (SELECT v1.b FROM v1, t2
WHERE t2.c = v1.c AND t2.c = v1.b AND v1.b = t3.c);
a b c
20 r r
DROP VIEW v1;
DROP TABLE t1,t2,t3;
#
# LP bug #873263: materialized view used in correlated IN subquery
#
CREATE TABLE t1 (a int, b int) ;
INSERT INTO t1 VALUES (5,4), (9,8);
CREATE TABLE t2 (a int, b int) ;
INSERT INTO t2 VALUES (4,5), (5,1);
CREATE ALGORITHM=TEMPTABLE VIEW v2 AS SELECT * FROM t2;
SET SESSION optimizer_switch='derived_with_keys=on';
EXPLAIN
SELECT * FROM t1 WHERE t1.b IN (SELECT v2.a FROM v2 WHERE v2.b = t1.a);
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 ALL NULL NULL NULL NULL 2 Using where
2011-11-07 13:39:02 +01:00
2 DEPENDENT SUBQUERY <derived3> ref key0 key0 5 test.t1.a 2 Using where
2011-11-02 10:48:41 +01:00
3 DERIVED t2 ALL NULL NULL NULL NULL 2
SELECT * FROM t1 WHERE t1.b IN (SELECT v2.a FROM v2 WHERE v2.b = t1.a);
a b
5 4
DROP VIEW v2;
DROP TABLE t1,t2;
set optimizer_switch= @tmp_subselect_extra_derived;
set optimizer_switch= @subselect_extra_no_sj_tmp;
2011-11-15 22:03:00 +01:00
set @optimizer_switch_for_subselect_extra_test=null;
2018-08-15 14:21:37 +02:00
#
# MDEV-6439: Server crashes in Explain_union::print_explain with explain in slow log, tis620 charset
#
2018-08-21 14:20:34 +02:00
connect con1,localhost,root,,;
2018-08-15 14:21:37 +02:00
SET NAMES tis620;
set @tmp= @@global.slow_query_log;
SET GLOBAL slow_query_log = 1;
SET long_query_time = 0.000001;
SET log_slow_verbosity = 'explain';
CREATE TABLE t1 (a VARCHAR(3)) ENGINE=MyISAM;
SELECT * FROM t1 WHERE a >= ANY ( SELECT 'foo');
a
SELECT * FROM t1 WHERE a >= ANY ( SELECT 'foo' UNION SELECT 'bar' );
ERROR HY000: Illegal mix of collations (tis620_thai_ci,COERCIBLE) and (latin1_swedish_ci,IMPLICIT) for operation '<='
create table t2 (b int);
insert into t2 values (1),(2),(3);
SELECT * FROM t1 WHERE a >= ANY ( SELECT 'foo' FROM t2);
ERROR HY000: Illegal mix of collations (tis620_thai_ci,COERCIBLE) and (latin1_swedish_ci,IMPLICIT) for operation '<='
drop table t1,t2;
SET GLOBAL slow_query_log=@tmp;
2018-08-21 14:20:34 +02:00
disconnect con1;
connection default;
