mirror of
https://github.com/MariaDB/server.git
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1033 lines
38 KiB
Text
1033 lines
38 KiB
Text
drop table if exists t0, t1, t2, t3, t4, t5, t6;
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drop view if exists v1, v2;
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SET @save_optimizer_switch=@@optimizer_switch;
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SET optimizer_switch='outer_join_with_cache=off';
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create table t1 (a int);
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insert into t1 values (0),(1),(2),(3);
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create table t0 as select * from t1;
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create table t2 (a int primary key, b int)
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as select a, a as b from t1 where a in (1,2);
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create table t3 (a int primary key, b int)
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as select a, a as b from t1 where a in (1,3);
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# This will be eliminated:
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explain select t1.a from t1 left join t2 on t2.a=t1.a;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 4
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explain extended select t1.a from t1 left join t2 on t2.a=t1.a;
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id select_type table type possible_keys key key_len ref rows filtered Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 4 100.00
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Warnings:
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Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where 1
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select t1.a from t1 left join t2 on t2.a=t1.a;
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a
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0
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1
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2
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3
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# This will not be eliminated as t2.b is in in select list:
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explain select * from t1 left join t2 on t2.a=t1.a;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 4
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1 SIMPLE t2 eq_ref PRIMARY PRIMARY 4 test.t1.a 1 Using where
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# This will not be eliminated as t2.b is in in order list:
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explain select t1.a from t1 left join t2 on t2.a=t1.a order by t2.b;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 4 Using temporary; Using filesort
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1 SIMPLE t2 eq_ref PRIMARY PRIMARY 4 test.t1.a 1 Using where
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# This will not be eliminated as t2.b is in group list:
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explain select t1.a from t1 left join t2 on t2.a=t1.a group by t2.b;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 4 Using temporary; Using filesort
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1 SIMPLE t2 eq_ref PRIMARY PRIMARY 4 test.t1.a 1 Using where
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# This will not be eliminated as t2.b is in the WHERE
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explain select t1.a from t1 left join t2 on t2.a=t1.a where t2.b < 3 or t2.b is null;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 4
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1 SIMPLE t2 eq_ref PRIMARY PRIMARY 4 test.t1.a 1 Using where
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# Elimination of multiple tables:
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explain select t1.a from t1 left join (t2 join t3) on t2.a=t1.a and t3.a=t1.a;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 4
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# Elimination of multiple tables (2):
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explain select t1.a from t1 left join (t2 join t3 on t2.b=t3.b) on t2.a=t1.a and t3.a=t1.a;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 4
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# Elimination when done within an outer join nest:
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explain extended
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select t0.*
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from
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t0 left join (t1 left join (t2 join t3 on t2.b=t3.b) on t2.a=t1.a and
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t3.a=t1.a) on t0.a=t1.a;
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id select_type table type possible_keys key key_len ref rows filtered Extra
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1 SIMPLE t0 ALL NULL NULL NULL NULL 4 100.00
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1 SIMPLE t1 ALL NULL NULL NULL NULL 4 100.00 Using where
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Warnings:
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Note 1003 select `test`.`t0`.`a` AS `a` from `test`.`t0` left join (`test`.`t1`) on(`test`.`t1`.`a` = `test`.`t0`.`a`) where 1
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# Elimination with aggregate functions
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explain select count(*) from t1 left join t2 on t2.a=t1.a;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 4
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explain select count(1) from t1 left join t2 on t2.a=t1.a;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 4
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explain select count(1) from t1 left join t2 on t2.a=t1.a group by t1.a;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 4 Using temporary; Using filesort
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This must not use elimination:
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explain select count(1) from t1 left join t2 on t2.a=t1.a group by t2.a;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 4 Using temporary; Using filesort
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1 SIMPLE t2 eq_ref PRIMARY PRIMARY 4 test.t1.a 1 Using where; Using index
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drop table t0, t1, t2, t3;
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create table t0 ( id integer, primary key (id));
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create table t1 (
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id integer,
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attr1 integer,
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primary key (id),
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key (attr1)
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);
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create table t2 (
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id integer,
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attr2 integer,
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fromdate date,
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primary key (id, fromdate),
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key (attr2,fromdate)
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);
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insert into t0 values (0),(1),(2),(3),(4),(5),(6),(7),(8),(9);
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insert into t0 select A.id + 10*B.id from t0 A, t0 B where B.id > 0;
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insert into t1 select id, id from t0;
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insert into t2 select id, id, date_add('2009-06-22', interval id day) from t0;
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insert into t2 select id, id+1, date_add('2008-06-22', interval id day) from t0;
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create view v1 as
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select
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f.id, a1.attr1, a2.attr2
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from
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t0 f
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left join t1 a1 on a1.id=f.id
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left join t2 a2 on a2.id=f.id and
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a2.fromdate=(select MAX(fromdate) from
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t2 where id=a2.id);
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create view v2 as
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select
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f.id, a1.attr1, a2.attr2
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from
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t0 f
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left join t1 a1 on a1.id=f.id
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left join t2 a2 on a2.id=f.id and
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a2.fromdate=(select MAX(fromdate) from
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t2 where id=f.id);
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This should use one table:
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explain select id from v1 where id=2;
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id select_type table type possible_keys key key_len ref rows Extra
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1 PRIMARY f const PRIMARY PRIMARY 4 const 1 Using index
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This should use one table:
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explain extended select id from v1 where id in (1,2,3,4);
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id select_type table type possible_keys key key_len ref rows filtered Extra
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1 PRIMARY f range PRIMARY PRIMARY 4 NULL 4 100.00 Using where; Using index
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Warnings:
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Note 1276 Field or reference 'test.a2.id' of SELECT #3 was resolved in SELECT #2
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Note 1003 /* select#1 */ select `f`.`id` AS `id` from `test`.`t0` `f` where `f`.`id` in (1,2,3,4)
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This should use facts and a1 tables:
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explain extended select id from v1 where attr1 between 12 and 14;
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id select_type table type possible_keys key key_len ref rows filtered Extra
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1 PRIMARY a1 range PRIMARY,attr1 attr1 5 NULL 2 100.00 Using index condition
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1 PRIMARY f eq_ref PRIMARY PRIMARY 4 test.a1.id 1 100.00 Using index
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Warnings:
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Note 1276 Field or reference 'test.a2.id' of SELECT #3 was resolved in SELECT #2
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Note 1003 /* select#1 */ select `f`.`id` AS `id` from `test`.`t0` `f` join `test`.`t1` `a1` where `f`.`id` = `a1`.`id` and `a1`.`attr1` between 12 and 14
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This should use facts, a2 and its subquery:
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explain extended select id from v1 where attr2 between 12 and 14;
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id select_type table type possible_keys key key_len ref rows filtered Extra
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1 PRIMARY a2 range PRIMARY,attr2 attr2 5 NULL 4 100.00 Using index condition; Using where
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1 PRIMARY f eq_ref PRIMARY PRIMARY 4 test.a2.id 1 100.00 Using index
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3 DEPENDENT SUBQUERY t2 ref PRIMARY PRIMARY 4 test.a2.id 2 100.00 Using index
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Warnings:
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Note 1276 Field or reference 'test.a2.id' of SELECT #3 was resolved in SELECT #2
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Note 1003 /* select#1 */ select `f`.`id` AS `id` from `test`.`t0` `f` join `test`.`t2` `a2` where `f`.`id` = `a2`.`id` and `a2`.`attr2` between 12 and 14 and `a2`.`fromdate` = <expr_cache><`a2`.`id`>((/* select#3 */ select max(`test`.`t2`.`fromdate`) from `test`.`t2` where `test`.`t2`.`id` = `a2`.`id`))
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This should use one table:
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explain select id from v2 where id=2;
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id select_type table type possible_keys key key_len ref rows Extra
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1 PRIMARY f const PRIMARY PRIMARY 4 const 1 Using index
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This should use one table:
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explain extended select id from v2 where id in (1,2,3,4);
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id select_type table type possible_keys key key_len ref rows filtered Extra
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1 PRIMARY f range PRIMARY PRIMARY 4 NULL 4 100.00 Using where; Using index
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Warnings:
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Note 1276 Field or reference 'test.f.id' of SELECT #3 was resolved in SELECT #2
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Note 1003 /* select#1 */ select `f`.`id` AS `id` from `test`.`t0` `f` where `f`.`id` in (1,2,3,4)
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This should use facts and a1 tables:
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explain extended select id from v2 where attr1 between 12 and 14;
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id select_type table type possible_keys key key_len ref rows filtered Extra
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1 PRIMARY a1 range PRIMARY,attr1 attr1 5 NULL 2 100.00 Using index condition
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1 PRIMARY f eq_ref PRIMARY PRIMARY 4 test.a1.id 1 100.00 Using index
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Warnings:
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Note 1276 Field or reference 'test.f.id' of SELECT #3 was resolved in SELECT #2
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Note 1003 /* select#1 */ select `f`.`id` AS `id` from `test`.`t0` `f` join `test`.`t1` `a1` where `f`.`id` = `a1`.`id` and `a1`.`attr1` between 12 and 14
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This should use facts, a2 and its subquery:
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explain extended select id from v2 where attr2 between 12 and 14;
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id select_type table type possible_keys key key_len ref rows filtered Extra
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1 PRIMARY a2 range PRIMARY,attr2 attr2 5 NULL 4 100.00 Using index condition
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1 PRIMARY f eq_ref PRIMARY PRIMARY 4 test.a2.id 1 100.00 Using where; Using index
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3 DEPENDENT SUBQUERY t2 ref PRIMARY PRIMARY 4 test.f.id 2 100.00 Using index
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Warnings:
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Note 1276 Field or reference 'test.f.id' of SELECT #3 was resolved in SELECT #2
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Note 1003 /* select#1 */ select `f`.`id` AS `id` from `test`.`t0` `f` join `test`.`t2` `a2` where `f`.`id` = `a2`.`id` and `a2`.`attr2` between 12 and 14 and `a2`.`fromdate` = <expr_cache><`f`.`id`>((/* select#3 */ select max(`test`.`t2`.`fromdate`) from `test`.`t2` where `test`.`t2`.`id` = `f`.`id`))
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drop view v1, v2;
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drop table t0, t1, t2;
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create table t1 (a int);
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insert into t1 values (0),(1),(2),(3);
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create table t2 (pk1 int, pk2 int, pk3 int, col int, primary key(pk1, pk2, pk3));
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insert into t2 select a,a,a,a from t1;
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This must use only t1:
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explain select t1.* from t1 left join t2 on t2.pk1=t1.a and
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t2.pk2=t2.pk1+1 and
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t2.pk3=t2.pk2+1;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 4
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This must use only t1:
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explain select t1.* from t1 left join t2 on t2.pk1=t1.a and
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t2.pk3=t2.pk1+1 and
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t2.pk2=t2.pk3+1;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 4
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This must use both:
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explain select t1.* from t1 left join t2 on t2.pk1=t1.a and
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t2.pk3=t2.pk1+1 and
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t2.pk2=t2.pk3+t2.col;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 4
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1 SIMPLE t2 ref PRIMARY PRIMARY 4 test.t1.a 1 Using where
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This must use only t1:
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explain select t1.* from t1 left join t2 on t2.pk2=t1.a and
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t2.pk1=t2.pk2+1 and
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t2.pk3=t2.pk1;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 4
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drop table t1, t2;
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create table t1 (pk int primary key, col int);
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insert into t1 values (1,1),(2,2);
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create table t2 like t1;
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insert into t2 select * from t1;
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create table t3 like t1;
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insert into t3 select * from t1;
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explain
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select t1.* from t1 left join ( t2 left join t3 on t3.pk=t2.col) on t2.col=t1.col;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 2
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1 SIMPLE t2 ALL NULL NULL NULL NULL 2 Using where
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explain
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select t1.*, t2.* from t1 left join (t2 left join t3 on t3.pk=t2.col) on t2.pk=t1.col;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 2
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1 SIMPLE t2 eq_ref PRIMARY PRIMARY 4 test.t1.col 1 Using where
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explain select t1.*
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from
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t1 left join ( t2 left join t3 on t3.pk=t2.col or t3.pk=t2.col)
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on t2.col=t1.col or t2.col=t1.col;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 2
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1 SIMPLE t2 ALL NULL NULL NULL NULL 2 Using where
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explain select t1.*, t2.*
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from
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t1 left join
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(t2 left join t3 on t3.pk=t2.col or t3.pk=t2.col)
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on t2.pk=t1.col or t2.pk=t1.col;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 2
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1 SIMPLE t2 eq_ref PRIMARY PRIMARY 4 test.t1.col 1 Using where
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drop table t1, t2, t3;
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#
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# Check things that look like functional dependencies but really are not
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#
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create table t1 (a char(10) character set latin1 collate latin1_general_ci primary key);
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insert into t1 values ('foo');
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insert into t1 values ('bar');
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create table t2 (a char(10) character set latin1 collate latin1_general_cs primary key);
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insert into t2 values ('foo');
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insert into t2 values ('FOO');
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this must not use table elimination:
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explain select t1.* from t1 left join t2 on t2.a='foo' collate latin1_general_ci;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index NULL PRIMARY 10 NULL 2 Using index
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1 SIMPLE t2 index PRIMARY PRIMARY 10 NULL 2 Using where; Using index
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Warnings:
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Note 1105 Cannot use key `PRIMARY` part[0] for lookup: `test`.`t2`.`a` of collation `latin1_general_cs` = "'foo' collate latin1_general_ci" of collation `latin1_general_ci`
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this must not use table elimination:
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explain select t1.* from t1 left join t2 on t2.a=t1.a collate latin1_general_ci;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index NULL PRIMARY 10 NULL 2 Using index
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1 SIMPLE t2 ALL PRIMARY NULL NULL NULL 2 Range checked for each record (index map: 0x1)
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Warnings:
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Note 1105 Cannot use key `PRIMARY` part[0] for lookup: `test`.`t2`.`a` of collation `latin1_general_cs` = "`t1`.`a` collate latin1_general_ci" of collation `latin1_general_ci`
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drop table t1,t2;
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create table t1 (a int primary key);
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insert into t1 values (1),(2);
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create table t2 (a char(10) primary key);
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insert into t2 values ('1'),('1.0');
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this must not use table elimination:
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explain select t1.* from t1 left join t2 on t2.a=1;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index NULL PRIMARY 4 NULL 2 Using index
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1 SIMPLE t2 index PRIMARY PRIMARY 10 NULL 2 Using where; Using index
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Warnings:
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Note 1105 Cannot use key `PRIMARY` part[0] for lookup: `test`.`t2`.`a` of type `char` = "1" of type `int`
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this must not use table elimination:
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explain select t1.* from t1 left join t2 on t2.a=t1.a;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index NULL PRIMARY 4 NULL 2 Using index
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1 SIMPLE t2 ALL PRIMARY NULL NULL NULL 2 Range checked for each record (index map: 0x1)
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Warnings:
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Note 1105 Cannot use key `PRIMARY` part[0] for lookup: `test`.`t2`.`a` of type `char` = "`t1`.`a`" of type `int`
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drop table t1, t2;
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create table t1 (a char(10) primary key);
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insert into t1 values ('foo'),('bar');
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create table t2 (a char(10), unique key(a(2)));
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insert into t2 values
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('foo'),('bar'),('boo'),('car'),('coo'),('par'),('doo'),('tar');
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explain select t1.* from t1 left join t2 on t2.a=t1.a;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 index NULL PRIMARY 10 NULL 2 Using index
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1 SIMPLE t2 eq_ref a a 3 test.t1.a 1 Using where
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drop table t1, t2;
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#
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# check UPDATE/DELETE that look like they could be eliminated
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#
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create table t1 (a int primary key, b int);
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insert into t1 values (1,1),(2,2),(3,3);
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create table t2 like t1;
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insert into t2 select * from t1;
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update t1 left join t2 using (a) set t2.a=t2.a+100;
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select * from t1;
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a b
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1 1
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2 2
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3 3
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select * from t2;
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a b
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101 1
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102 2
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103 3
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delete from t2;
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insert into t2 select * from t1;
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delete t2 from t1 left join t2 using (a);
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select * from t1;
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a b
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1 1
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2 2
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3 3
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select * from t2;
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a b
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drop table t1, t2;
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#
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# Tests with various edge-case ON expressions
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#
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create table t1 (a int, b int, c int, d int);
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insert into t1 values (0,0,0,0),(1,1,1,1),(2,2,2,2),(3,3,3,3);
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create table t2 (pk int primary key, b int)
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as select a as pk, a as b from t1 where a in (1,2);
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create table t3 (pk1 int, pk2 int, b int, unique(pk1,pk2));
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insert into t3 select a as pk1, a as pk2, a as b from t1 where a in (1,3);
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explain select t1.a from t1 left join t2 on t2.pk=t1.a and t2.b<t1.b;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 4
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explain select t1.a from t1 left join t2 on t2.pk=t1.a or t2.b<t1.b;
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id select_type table type possible_keys key key_len ref rows Extra
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1 SIMPLE t1 ALL NULL NULL NULL NULL 4
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1 SIMPLE t2 ALL PRIMARY NULL NULL NULL 2 Using where
|
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explain select t1.a from t1 left join t2 on t2.b<t1.b or t2.pk=t1.a;
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id select_type table type possible_keys key key_len ref rows Extra
|
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1 SIMPLE t1 ALL NULL NULL NULL NULL 4
|
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1 SIMPLE t2 ALL PRIMARY NULL NULL NULL 2 Using where
|
|
explain select t1.a from t1 left join t2 on t2.pk between 10 and 20;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
|
|
1 SIMPLE t2 range PRIMARY PRIMARY 4 NULL 1 Using where; Using index
|
|
explain select t1.a from t1 left join t2 on t2.pk between 0.5 and 1.5;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
|
|
1 SIMPLE t2 range PRIMARY PRIMARY 4 NULL 2 Using where; Using index
|
|
explain select t1.a from t1 left join t2 on t2.pk between 10 and 10;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
|
|
explain select t1.a from t1 left join t2 on t2.pk in (10);
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
|
|
explain select t1.a from t1 left join t2 on t2.pk in (t1.a);
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
|
|
explain select t1.a from t1 left join t2 on TRUE;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
|
|
1 SIMPLE t2 index NULL PRIMARY 4 NULL 2 Using where; Using index
|
|
explain select t1.a from t1 left join t3 on t3.pk1=t1.a and t3.pk2 IS NULL;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
|
|
drop table t1,t2,t3;
|
|
#
|
|
# Multi-equality tests
|
|
#
|
|
create table t1 (a int, b int, c int, d int);
|
|
insert into t1 values (0,0,0,0),(1,1,1,1),(2,2,2,2),(3,3,3,3);
|
|
create table t2 (pk int primary key, b int, c int);
|
|
insert into t2 select a,a,a from t1 where a in (1,2);
|
|
explain
|
|
select t1.*
|
|
from t1 left join t2 on t2.pk=t2.c and t2.b=t1.a and t1.a=t1.b and t2.c=t2.b
|
|
where t1.d=1;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 4 Using where
|
|
explain
|
|
select t1.*
|
|
from
|
|
t1
|
|
left join
|
|
t2
|
|
on (t2.pk=t2.c and t2.b=t1.a and t1.a=t1.b and t2.c=t2.b) or
|
|
(t2.pk=t2.c and t2.b=t1.a and t1.a=t1.b and t2.c=t2.b)
|
|
where t1.d=1;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 4 Using where
|
|
#This can't be eliminated:
|
|
explain
|
|
select t1.*
|
|
from
|
|
t1
|
|
left join
|
|
t2
|
|
on (t2.pk=t2.c and t2.b=t1.a and t2.c=t1.b) or
|
|
(t2.pk=t2.c and t1.a=t1.b and t2.c=t1.b)
|
|
where t1.d=1;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 4 Using where
|
|
1 SIMPLE t2 eq_ref PRIMARY PRIMARY 4 test.t1.b 1 Using where
|
|
explain
|
|
select t1.*
|
|
from
|
|
t1
|
|
left join
|
|
t2
|
|
on (t2.pk=t2.c and t2.b=t1.a and t2.c=t1.b) or
|
|
(t2.pk=t2.c and t2.c=t1.b)
|
|
;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
|
|
explain
|
|
select t1.*
|
|
from t1 left join t2 on t2.pk=3 or t2.pk= 4;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
|
|
1 SIMPLE t2 range PRIMARY PRIMARY 4 NULL 2 Using where; Using index
|
|
explain
|
|
select t1.*
|
|
from t1 left join t2 on t2.pk=3 or t2.pk= 3;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
|
|
explain
|
|
select t1.*
|
|
from t1 left join t2 on (t2.pk=3 and t2.b=3) or (t2.pk= 4 and t2.b=3);
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 4
|
|
1 SIMPLE t2 range PRIMARY PRIMARY 4 NULL 2 Using where
|
|
drop table t1, t2;
|
|
#
|
|
# LPBUG#523593: Running RQG optimizer_no_subquery crashes MariaDB
|
|
#
|
|
CREATE TABLE t1 (
|
|
`pk` int(11) NOT NULL AUTO_INCREMENT,
|
|
`col_int_nokey` int(11) DEFAULT NULL,
|
|
`col_int_key` int(11) DEFAULT NULL,
|
|
`col_date_key` date DEFAULT NULL,
|
|
`col_date_nokey` date DEFAULT NULL,
|
|
`col_time_key` time DEFAULT NULL,
|
|
`col_time_nokey` time DEFAULT NULL,
|
|
`col_datetime_key` datetime DEFAULT NULL,
|
|
`col_datetime_nokey` datetime DEFAULT NULL,
|
|
`col_varchar_key` varchar(1) DEFAULT NULL,
|
|
`col_varchar_nokey` varchar(1) DEFAULT NULL,
|
|
PRIMARY KEY (`pk`),
|
|
KEY `col_int_key` (`col_int_key`),
|
|
KEY `col_date_key` (`col_date_key`),
|
|
KEY `col_time_key` (`col_time_key`),
|
|
KEY `col_datetime_key` (`col_datetime_key`),
|
|
KEY `col_varchar_key` (`col_varchar_key`,`col_int_key`)
|
|
);
|
|
CREATE TABLE t2 LIKE t1;
|
|
INSERT INTO t1 VALUES
|
|
(10,7,8,NULL,NULL,'01:27:35','01:27:35','2002-02-26 06:14:37','2002-02-26 06:14:37','v','v'),
|
|
(11,1,9,'2006-06-14','2006-06-14','19:48:31','19:48:31','1900-01-01 00:00:00','1900-01-01 00:00:00','r','r');
|
|
INSERT INTO t2 SELECT * FROM t1;
|
|
SELECT table2.col_int_key AS field1
|
|
FROM (
|
|
t2 AS table1
|
|
RIGHT OUTER JOIN
|
|
(
|
|
( t1 AS table2 STRAIGHT_JOIN
|
|
t1 AS table3 ON (
|
|
(table3.col_varchar_nokey = table2.col_varchar_key ) AND
|
|
(table3.pk = table2.col_int_key))
|
|
)
|
|
) ON
|
|
(
|
|
(table3.col_varchar_key = table2.col_varchar_key) OR
|
|
(table3.col_int_key = table2.pk)
|
|
)
|
|
)
|
|
HAVING field1 < 216;
|
|
field1
|
|
DROP TABLE t1, t2;
|
|
#
|
|
# LPBUG#524025 Running RQG outer_join test leads to crash
|
|
#
|
|
CREATE TABLE t0 (
|
|
pk int(11) NOT NULL AUTO_INCREMENT,
|
|
PRIMARY KEY (pk)
|
|
);
|
|
CREATE TABLE t1 (
|
|
col_int int(11) DEFAULT NULL,
|
|
col_int_key int(11) DEFAULT NULL,
|
|
pk int(11) NOT NULL AUTO_INCREMENT,
|
|
col_varchar_10_latin1 varchar(10) DEFAULT NULL,
|
|
PRIMARY KEY (pk)
|
|
);
|
|
INSERT INTO t1 VALUES (5,5,1,'t'), (NULL,NULL,2,'y');
|
|
CREATE TABLE t2 (
|
|
col_int int(11) DEFAULT NULL
|
|
);
|
|
INSERT INTO t2 VALUES (8), (4);
|
|
CREATE TABLE t3 (
|
|
pk int(11) NOT NULL AUTO_INCREMENT,
|
|
PRIMARY KEY (pk)
|
|
);
|
|
INSERT INTO t3 VALUES (1),(8);
|
|
CREATE TABLE t4 (
|
|
pk int(11) NOT NULL AUTO_INCREMENT,
|
|
col_varchar_1024_latin1_key varchar(1024) DEFAULT NULL,
|
|
col_int int(11) DEFAULT NULL,
|
|
PRIMARY KEY (pk)
|
|
);
|
|
INSERT INTO t4 VALUES (1,'o',1), (2,'w',2);
|
|
CREATE TABLE t5 (
|
|
col_varchar_1024_utf8_key varchar(1024) CHARACTER SET utf8 DEFAULT NULL,
|
|
col_varchar_1024_latin1_key varchar(1024) DEFAULT NULL,
|
|
col_varchar_10_utf8_key varchar(1024) CHARACTER SET utf8 DEFAULT NULL,
|
|
pk int(11) NOT NULL AUTO_INCREMENT,
|
|
col_int_key int(11) DEFAULT NULL,
|
|
PRIMARY KEY (pk)
|
|
);
|
|
INSERT INTO t5 VALUES ('k','a','z',1,2),('x','a','w',2,7);
|
|
CREATE TABLE t6 (
|
|
col_int int(11) DEFAULT NULL,
|
|
col_int_key int(11) DEFAULT NULL
|
|
);
|
|
INSERT INTO t6 VALUES (6,1),(8,3);
|
|
SELECT
|
|
table3.col_int AS field1,
|
|
table1.col_int AS field2,
|
|
table1.col_int_key AS field3,
|
|
table1.pk AS field4,
|
|
table1.col_int AS field5,
|
|
table2.col_int AS field6
|
|
FROM
|
|
t1 AS table1
|
|
LEFT OUTER JOIN
|
|
t4 AS table2
|
|
LEFT JOIN t6 AS table3
|
|
RIGHT JOIN t3 AS table4
|
|
LEFT JOIN t5 AS table5 ON table4.pk = table5.pk
|
|
LEFT JOIN t0 AS table6 ON table5.col_int_key = table6.pk
|
|
ON table3.col_int_key = table5.pk
|
|
ON table2.col_varchar_1024_latin1_key = table5.col_varchar_10_utf8_key
|
|
LEFT JOIN t6 AS table7 ON table2.pk = table7.col_int
|
|
ON table1.col_varchar_10_latin1 = table5.col_varchar_1024_latin1_key
|
|
LEFT JOIN t2 AS table8 ON table3.col_int = table8.col_int
|
|
WHERE
|
|
table1.col_int_key < table2.pk
|
|
HAVING
|
|
field4 != 6;
|
|
field1 field2 field3 field4 field5 field6
|
|
drop table t0,t1,t2,t3,t4,t5,t6;
|
|
#
|
|
# BUG#675118: Elimination of a table results in an invalid execution plan
|
|
#
|
|
CREATE TABLE t1 (f1 int(11), PRIMARY KEY (f1)) ;
|
|
CREATE TABLE t2 (f4 varchar(1024), KEY (f4)) ;
|
|
Warnings:
|
|
Note 1071 Specified key was too long; max key length is 1000 bytes
|
|
INSERT IGNORE INTO t2 VALUES ('xcddwntkbxyorzdv'),
|
|
('cnxxcddwntkbxyor'),('r'),('r'), ('did'),('I'),('when'),
|
|
('hczkfqjeggivdvac'),('e'),('okay'),('up');
|
|
CREATE TABLE t3 (f4 varchar(1024), f1 int(11), f2 int(11)) ;
|
|
INSERT IGNORE INTO t3 VALUES ('f','4','0'),('n','5','-996540416');
|
|
CREATE TABLE t4 (f1 int(11), f3 varchar(10)) ;
|
|
INSERT IGNORE INTO t4 VALUES ('8','n'),('9','nwzcerzsgx'),('10','c');
|
|
CREATE TABLE t5 (f5 int(11), KEY (f5)) ;
|
|
EXPLAIN
|
|
SELECT t3.f2
|
|
FROM t2
|
|
LEFT JOIN t3
|
|
LEFT JOIN t4
|
|
LEFT JOIN t1 ON t4.f1 = t1.f1
|
|
JOIN t5 ON t4.f3 ON t3.f1 = t5.f5 ON t2.f4 = t3.f4
|
|
WHERE t3.f2 ;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t3 ALL NULL NULL NULL NULL 2 Using where
|
|
1 SIMPLE t5 ref f5 f5 5 test.t3.f1 2 Using where; Using index
|
|
1 SIMPLE t4 ALL NULL NULL NULL NULL 3 Using where
|
|
1 SIMPLE t2 ALL f4 NULL NULL NULL 11 Using where; Using join buffer (flat, BNL join)
|
|
# ^^ The above must not produce a QEP of t3,t5,t2,t4
|
|
# as that violates the "no interleaving of outer join nests" rule.
|
|
DROP TABLE t1,t2,t3,t4,t5;
|
|
#
|
|
# BUG#997747: Assertion `join->best_read < ((double)1.79..5e+308L)'
|
|
# failed in greedy_search with LEFT JOINs and unique keys
|
|
#
|
|
CREATE TABLE t1 (a1 INT);
|
|
CREATE TABLE t2 (b1 INT);
|
|
CREATE TABLE t3 (c1 INT, UNIQUE KEY(c1));
|
|
CREATE TABLE t4 (d1 INT, UNIQUE KEY(d1));
|
|
CREATE TABLE t5 (e1 INT);
|
|
INSERT INTO t1 VALUES (1),(2);
|
|
INSERT INTO t2 VALUES (2),(3);
|
|
INSERT INTO t3 VALUES (3),(4);
|
|
INSERT INTO t4 VALUES (4),(5);
|
|
INSERT INTO t5 VALUES (5),(6);
|
|
SELECT a1 FROM t1 LEFT JOIN t2 LEFT JOIN t3 LEFT JOIN t4
|
|
ON c1 = d1 ON d1 = b1 ON a1 = b1
|
|
LEFT JOIN t5 ON a1 = e1 ;
|
|
a1
|
|
1
|
|
2
|
|
DROP TABLE t1,t2,t3,t4,t5;
|
|
#
|
|
# BUG#884184: Wrong result with RIGHT JOIN + derived_merge
|
|
#
|
|
CREATE TABLE t1 (a int(11), b varchar(1)) ;
|
|
INSERT IGNORE INTO t1 VALUES (0,'g');
|
|
CREATE TABLE t3 ( a varchar(1)) ;
|
|
INSERT IGNORE INTO t3 VALUES ('g');
|
|
CREATE TABLE t2 ( a int(11) NOT NULL, PRIMARY KEY (a));
|
|
INSERT INTO t2 VALUES (9), (10);
|
|
create view v1 as SELECT t1.* FROM t1 LEFT JOIN t2 ON ( t1.a = t2.a ) WHERE t2.a <> 0;
|
|
SELECT alias1.* FROM t3 LEFT JOIN v1 as alias1 ON ( t3.a = alias1.b );
|
|
a b
|
|
NULL NULL
|
|
EXPLAIN SELECT alias1.* FROM t3 LEFT JOIN v1 as alias1 ON ( t3.a = alias1.b );
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 SIMPLE t3 system NULL NULL NULL NULL 1
|
|
1 SIMPLE t1 ALL NULL NULL NULL NULL 1 Using where
|
|
1 SIMPLE t2 eq_ref PRIMARY PRIMARY 4 test.t1.a 1 Using index
|
|
drop view v1;
|
|
DROP TABLE t1,t2,t3;
|
|
#
|
|
# MDEV-5344: LEFT OUTER JOIN table data is lost in ON DUPLICATE KEY UPDATE section
|
|
#
|
|
create table t1 (
|
|
id int(10) unsigned NOT NULL DEFAULT '0',
|
|
v int(10) unsigned DEFAULT '0',
|
|
PRIMARY KEY (id)
|
|
);
|
|
create table t2 (
|
|
id int(10) unsigned NOT NULL DEFAULT '0',
|
|
PRIMARY KEY (id)
|
|
) ;
|
|
create table t3 (
|
|
id int(10) unsigned NOT NULL DEFAULT '0',
|
|
v int(10) unsigned DEFAULT '0',
|
|
PRIMARY KEY (id)
|
|
);
|
|
insert into t1 values (1, 10), (2, 10);
|
|
insert into t2 values (1), (2);
|
|
insert into t3 values (1, 20);
|
|
insert into t1
|
|
select t2.id, 5 from t2 LEFT OUTER JOIN t3 ON t2.id = t3.id
|
|
on duplicate key update t1.v = t3.v;
|
|
select * from t1;
|
|
id v
|
|
1 20
|
|
2 NULL
|
|
drop table t1,t2,t3;
|
|
#
|
|
# BUG#919878: Assertion `!eliminated_tables...
|
|
#
|
|
CREATE TABLE t1 ( a INT );
|
|
INSERT INTO t1 VALUES (1);
|
|
CREATE TABLE t2
|
|
( b INT, UNIQUE INDEX(b) );
|
|
INSERT INTO t2 VALUES (1),(2);
|
|
EXPLAIN EXTENDED
|
|
SELECT * FROM t2
|
|
WHERE b IN (
|
|
SELECT SUM(a) FROM t1 LEFT JOIN t2 ON b=a
|
|
);
|
|
id select_type table type possible_keys key key_len ref rows filtered Extra
|
|
1 PRIMARY t2 index NULL b 5 NULL 2 100.00 Using where; Using index
|
|
2 DEPENDENT SUBQUERY t1 system NULL NULL NULL NULL 1 100.00
|
|
Warnings:
|
|
Note 1003 /* select#1 */ select `test`.`t2`.`b` AS `b` from `test`.`t2` where <expr_cache><`test`.`t2`.`b`>(<in_optimizer>(`test`.`t2`.`b`,<exists>(/* select#2 */ select sum(1) from dual where 1 having <cache>(`test`.`t2`.`b`) = <ref_null_helper>(sum(1)))))
|
|
DROP TABLE t1,t2;
|
|
#
|
|
# MDEV-4840: Wrong result (missing rows) on LEFT JOIN with InnoDB tables
|
|
#
|
|
CREATE TABLE t1 (alpha3 VARCHAR(3));
|
|
INSERT INTO t1 VALUES ('USA'),('CAN');
|
|
CREATE TABLE t2 ( t3_code VARCHAR(3), name VARCHAR(64));
|
|
INSERT INTO t2 VALUES ('USA','Austin'),('USA','Boston');
|
|
CREATE TABLE t3 ( code VARCHAR(3), name VARCHAR(64), PRIMARY KEY (code), UNIQUE KEY (name));
|
|
INSERT INTO t3 VALUES ('CAN','Canada'),('USA','United States');
|
|
SELECT * FROM t1 LEFT JOIN ( t2 LEFT JOIN t3 ON t2.t3_code = t3.code ) ON t1.alpha3 = t3.code;
|
|
alpha3 t3_code name code name
|
|
USA USA Austin USA United States
|
|
USA USA Boston USA United States
|
|
CAN NULL NULL NULL NULL
|
|
SELECT t1.alpha3 FROM t1 LEFT JOIN ( t2 LEFT JOIN t3 ON t2.t3_code = t3.code ) ON t1.alpha3 = t3.code;
|
|
alpha3
|
|
USA
|
|
USA
|
|
CAN
|
|
DROP TABLE t1, t2, t3;
|
|
SET optimizer_switch=@save_optimizer_switch;
|
|
#
|
|
# MDEV-7893: table_elimination works wrong with on computed expression and compound unique key
|
|
# (just a testcase)
|
|
CREATE TABLE t1 (
|
|
PostID int(10) unsigned NOT NULL
|
|
) DEFAULT CHARSET=utf8;
|
|
INSERT INTO t1 (PostID) VALUES (1), (2);
|
|
CREATE TABLE t2 (
|
|
VoteID int(10) unsigned NOT NULL PRIMARY KEY AUTO_INCREMENT,
|
|
EntityID int(10) unsigned NOT NULL,
|
|
UserID int(10) unsigned NOT NULL,
|
|
UNIQUE KEY EntityID (EntityID,UserID)
|
|
) DEFAULT CHARSET=utf8;
|
|
INSERT INTO t2 (EntityID, UserID) VALUES (1, 30), (2, 30);
|
|
SELECT t1.*, T.Voted as Voted
|
|
FROM
|
|
t1 LEFT JOIN (
|
|
SELECT 1 AS Voted, EntityID
|
|
FROM t2
|
|
WHERE t2.UserID = '20' ) AS T
|
|
ON T.EntityID = t1.PostID
|
|
WHERE t1.PostID='1'
|
|
LIMIT 1;
|
|
PostID Voted
|
|
1 NULL
|
|
DROP TABLE t1,t2;
|
|
#
|
|
# MDEV-26278: Table elimination does not work across derived tables
|
|
#
|
|
create table t1 (a int, b int);
|
|
insert into t1 select seq, seq+10 from seq_1_to_10;
|
|
create table t11 (
|
|
a int not null,
|
|
b int,
|
|
key(a)
|
|
);
|
|
insert into t11 select A.seq, A.seq+B.seq
|
|
from
|
|
seq_1_to_10 A,
|
|
seq_1_to_100 B;
|
|
create table t12 (
|
|
pk int primary key,
|
|
col1 int
|
|
);
|
|
insert into t12 select seq, seq from seq_1_to_1000;
|
|
create view v2b as
|
|
select t11.a as a, count(*) as b
|
|
from t11 left join t12 on t12.pk=t11.b
|
|
group by t11.a;
|
|
# The whole v2b is eliminated
|
|
explain select t1.* from t1 left join v2b on v2b.a=t1.a;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 PRIMARY t1 ALL NULL NULL NULL NULL 10
|
|
# Check format JSON as well
|
|
explain format=JSON select t1.* from t1 left join v2b on t1.a=v2b.a;
|
|
EXPLAIN
|
|
{
|
|
"query_block": {
|
|
"select_id": 1,
|
|
"const_condition": "1",
|
|
"nested_loop": [
|
|
{
|
|
"table": {
|
|
"table_name": "t1",
|
|
"access_type": "ALL",
|
|
"rows": 10,
|
|
"filtered": 100
|
|
}
|
|
}
|
|
]
|
|
}
|
|
}
|
|
# Elimination of a whole subquery
|
|
explain select t1.* from t1 left join
|
|
(select t11.a as a, count(*) as b
|
|
from t11 left join t12 on t12.pk=t11.b
|
|
group by t11.a) v2b on v2b.a=t1.a;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 PRIMARY t1 ALL NULL NULL NULL NULL 10
|
|
# In this case v2b cannot be eliminated (since v2b.b is not unique)!
|
|
explain select t1.* from t1 left join v2b on t1.a=v2b.b;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 PRIMARY t1 ALL NULL NULL NULL NULL 10
|
|
1 PRIMARY <derived2> ref key0 key0 8 test.t1.a 10 Using where
|
|
2 DERIVED t11 ALL NULL NULL NULL NULL 1000 Using temporary; Using filesort
|
|
# Check format JSON as well
|
|
explain format=JSON select t1.* from t1 left join v2b on t1.a=v2b.b;
|
|
EXPLAIN
|
|
{
|
|
"query_block": {
|
|
"select_id": 1,
|
|
"const_condition": "1",
|
|
"nested_loop": [
|
|
{
|
|
"table": {
|
|
"table_name": "t1",
|
|
"access_type": "ALL",
|
|
"rows": 10,
|
|
"filtered": 100
|
|
}
|
|
},
|
|
{
|
|
"table": {
|
|
"table_name": "<derived2>",
|
|
"access_type": "ref",
|
|
"possible_keys": ["key0"],
|
|
"key": "key0",
|
|
"key_length": "8",
|
|
"used_key_parts": ["b"],
|
|
"ref": ["test.t1.a"],
|
|
"rows": 10,
|
|
"filtered": 100,
|
|
"attached_condition": "trigcond(t1.a = v2b.b and trigcond(t1.a is not null))",
|
|
"materialized": {
|
|
"query_block": {
|
|
"select_id": 2,
|
|
"const_condition": "1",
|
|
"filesort": {
|
|
"sort_key": "t11.a",
|
|
"temporary_table": {
|
|
"nested_loop": [
|
|
{
|
|
"table": {
|
|
"table_name": "t11",
|
|
"access_type": "ALL",
|
|
"rows": 1000,
|
|
"filtered": 100
|
|
}
|
|
}
|
|
]
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
]
|
|
}
|
|
}
|
|
create view v2c as
|
|
select t11.a as a, max(t12.col1) as b
|
|
from t11 left join t12 on t12.pk=t11.b
|
|
group by t11.a;
|
|
# The whole v2c is eliminated
|
|
explain select t1.* from t1 left join v2c on v2c.a=t1.a;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 PRIMARY t1 ALL NULL NULL NULL NULL 10
|
|
# Check format JSON as well
|
|
explain format=JSON select t1.* from t1 left join v2c on v2c.a=t1.a;
|
|
EXPLAIN
|
|
{
|
|
"query_block": {
|
|
"select_id": 1,
|
|
"const_condition": "1",
|
|
"nested_loop": [
|
|
{
|
|
"table": {
|
|
"table_name": "t1",
|
|
"access_type": "ALL",
|
|
"rows": 10,
|
|
"filtered": 100
|
|
}
|
|
}
|
|
]
|
|
}
|
|
}
|
|
# In this case v2c cannot be eliminated (since v2c.b is not unique)!
|
|
explain select t1.* from t1 left join v2c on t1.a=v2c.b;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 PRIMARY t1 ALL NULL NULL NULL NULL 10
|
|
1 PRIMARY <derived2> ref key0 key0 5 test.t1.a 10 Using where
|
|
2 DERIVED t11 ALL NULL NULL NULL NULL 1000 Using temporary; Using filesort
|
|
2 DERIVED t12 eq_ref PRIMARY PRIMARY 4 test.t11.b 1 Using where
|
|
# Check format JSON as well
|
|
explain format=JSON select t1.* from t1 left join v2c on t1.a=v2c.b;
|
|
EXPLAIN
|
|
{
|
|
"query_block": {
|
|
"select_id": 1,
|
|
"const_condition": "1",
|
|
"nested_loop": [
|
|
{
|
|
"table": {
|
|
"table_name": "t1",
|
|
"access_type": "ALL",
|
|
"rows": 10,
|
|
"filtered": 100
|
|
}
|
|
},
|
|
{
|
|
"table": {
|
|
"table_name": "<derived2>",
|
|
"access_type": "ref",
|
|
"possible_keys": ["key0"],
|
|
"key": "key0",
|
|
"key_length": "5",
|
|
"used_key_parts": ["b"],
|
|
"ref": ["test.t1.a"],
|
|
"rows": 10,
|
|
"filtered": 100,
|
|
"attached_condition": "trigcond(trigcond(t1.a is not null))",
|
|
"materialized": {
|
|
"query_block": {
|
|
"select_id": 2,
|
|
"const_condition": "1",
|
|
"filesort": {
|
|
"sort_key": "t11.a",
|
|
"temporary_table": {
|
|
"nested_loop": [
|
|
{
|
|
"table": {
|
|
"table_name": "t11",
|
|
"access_type": "ALL",
|
|
"rows": 1000,
|
|
"filtered": 100
|
|
}
|
|
},
|
|
{
|
|
"table": {
|
|
"table_name": "t12",
|
|
"access_type": "eq_ref",
|
|
"possible_keys": ["PRIMARY"],
|
|
"key": "PRIMARY",
|
|
"key_length": "4",
|
|
"used_key_parts": ["pk"],
|
|
"ref": ["test.t11.b"],
|
|
"rows": 1,
|
|
"filtered": 100,
|
|
"attached_condition": "trigcond(trigcond(t11.b is not null))"
|
|
}
|
|
}
|
|
]
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
]
|
|
}
|
|
}
|
|
# Create a view with multiple fields in the GROUP BY clause:
|
|
create view v2d as
|
|
select t11.a as a, t11.b as b, max(t12.col1) as max_col1
|
|
from t11 left join t12 on t12.pk=t11.b
|
|
group by t11.a, t11.b;
|
|
# This one must not be eliminated since only one of the GROUP BY fields is bound:
|
|
explain select t1.* from t1 left join v2d on v2d.a=t1.a;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 PRIMARY t1 ALL NULL NULL NULL NULL 10
|
|
1 PRIMARY <derived2> ref key0 key0 5 test.t1.a 10 Using where
|
|
2 DERIVED t11 ALL a NULL NULL NULL 1000 Using temporary; Using filesort
|
|
2 DERIVED t12 eq_ref PRIMARY PRIMARY 4 test.t11.b 1 Using where
|
|
# This must be eliminated since both fields are bound:
|
|
explain select t1.* from t1 left join v2d on v2d.a=t1.a and v2d.b=t1.b;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 PRIMARY t1 ALL NULL NULL NULL NULL 10
|
|
create table t13 (dt date, b int);
|
|
# Function year() in the GROUP BY list prevents treating this field
|
|
# as a unique key
|
|
create view v2e as
|
|
select year(t13.dt) as yyy, max(t12.col1) as max_col1
|
|
from t13 join t12 on t12.pk=t13.b
|
|
group by yyy;
|
|
# No elimination here since function year() is used
|
|
explain select t1.* from t1 left join v2e on v2e.yyy=t1.a;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 PRIMARY t1 ALL NULL NULL NULL NULL 10
|
|
1 PRIMARY <derived2> ref key0 key0 5 test.t1.a 2 Using where
|
|
2 DERIVED NULL NULL NULL NULL NULL NULL NULL no matching row in const table
|
|
create table t2 (a int, b int, c int);
|
|
insert into t2 select A.seq, B.seq, 123 from seq_1_to_3 A, seq_1_to_3 B;
|
|
# No elimination here since not all fields of the derived table's
|
|
# GROUP BY are on the SELECT list so D.a is not unique
|
|
explain select t1.* from t1 left join
|
|
(select a, count(*) as cnt from t2 group by a, b) D on D.a=t1.a;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 PRIMARY t1 ALL NULL NULL NULL NULL 10
|
|
1 PRIMARY <derived2> ref key0 key0 5 test.t1.a 2 Using where
|
|
2 DERIVED t2 ALL NULL NULL NULL NULL 9 Using temporary; Using filesort
|
|
# Still no elimination 'cause field D.b is just an alias for t2.a
|
|
explain select t1.* from t1 left join
|
|
(select a, a as b, count(*) as cnt from t2 group by a, b) D on D.a=t1.a and D.b=t1.b;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 PRIMARY t1 ALL NULL NULL NULL NULL 10
|
|
1 PRIMARY <derived2> ref key0 key0 10 test.t1.a,test.t1.b 2 Using where
|
|
2 DERIVED t2 ALL NULL NULL NULL NULL 9 Using temporary; Using filesort
|
|
Warnings:
|
|
Warning 1052 Column 'b' in GROUP BY is ambiguous
|
|
# Now both a and b fields are on the SELECT list and they are bound to t1
|
|
# so derived D must be eliminated
|
|
explain select t1.* from t1 left join
|
|
(select a as a1, b as b1, count(*) as cnt from t2 group by a, b) D
|
|
on D.a1=t1.a and D.b1=t1.b;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 PRIMARY t1 ALL NULL NULL NULL NULL 10
|
|
# Different order of fields in GROUP BY and SELECT lists
|
|
# must not hamper the elimination
|
|
explain select t1.* from t1 left join
|
|
(select count(*) as cnt, b, a from t2 group by a, b) D on D.a=t1.a and D.b=t1.b;
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 PRIMARY t1 ALL NULL NULL NULL NULL 10
|
|
drop view v2b, v2c, v2d, v2e;
|
|
drop table t1, t11, t12, t13, t2;
|
|
#
|
|
# End of MDEV-26278: Table elimination does not work across derived tables
|
|
#
|
|
#
|
|
# MDEV-28881: Server crashes in Dep_analysis_context::create_table_value/
|
|
# check_func_dependency
|
|
#
|
|
CREATE TABLE t1 (a1 int, a2 int);
|
|
INSERT INTO t1 VALUES (0,276),(5,277),(NULL,278);
|
|
CREATE TABLE t2 ( a1 int, a2 int, KEY a2 (a2));
|
|
INSERT INTO t2 VALUES (11,NULL),(185,0);
|
|
SELECT t1.* FROM t1 LEFT JOIN
|
|
( SELECT * FROM (SELECT t2.a1 AS a1, min(t2.a2) AS a2 FROM t2
|
|
WHERE t2.a2 <> NULL
|
|
GROUP BY t2.a1) dt
|
|
) dt2 ON dt2.a2 = t1.a2;
|
|
a1 a2
|
|
0 276
|
|
5 277
|
|
NULL 278
|
|
DROP TABLE t1, t2;
|
|
#
|
|
# MDEV-30007: SIGSEGV in st_select_lex_unit::is_derived_eliminated,
|
|
# runtime error: member access within null pointer of type
|
|
# 'struct TABLE' in st_select_lex_unit::is_derived_eliminated()
|
|
#
|
|
CREATE VIEW v AS SELECT 1 AS a;
|
|
SELECT ROUND ((SELECT 1 FROM v)) FROM v GROUP BY ROUND ((SELECT 1 FROM v));
|
|
ROUND ((SELECT 1 FROM v))
|
|
1
|
|
EXPLAIN
|
|
SELECT ROUND ((SELECT 1 FROM v)) FROM v GROUP BY ROUND ((SELECT 1 FROM v));
|
|
id select_type table type possible_keys key key_len ref rows Extra
|
|
1 PRIMARY <derived4> system NULL NULL NULL NULL 1
|
|
4 DERIVED NULL NULL NULL NULL NULL NULL NULL No tables used
|
|
2 SUBQUERY <derived5> system NULL NULL NULL NULL 1
|
|
5 DERIVED NULL NULL NULL NULL NULL NULL NULL No tables used
|
|
DROP VIEW v;
|
|
#
|
|
# End of 10.10 tests
|
|
#
|