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independent ALL/ANY subselect on top of WHERE clause (subselect without GROUP BY or aggregate functions) optimisation

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(SCRUM) (WL#1086)
This commit is contained in:
bell@sanja.is.com.ua
2003-07-24 15:26:21 +03:00
parent 07a70f79e8
commit ec74bb8d76
9 changed files with 130 additions and 21 deletions
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17
mysql-test/r/subselect.result
View File

@ -247,6 +247,10 @@ select * from t3 where a >= any (select b from t2);
a
6
7
explain select * from t3 where a >= any (select b from t2);
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t3 ALL NULL NULL NULL NULL 3 Using where
2 SUBQUERY t2 ALL NULL NULL NULL NULL 3
select * from t3 where a >= all (select b from t2);
a
7
@ -1317,3 +1321,16 @@ a (select count(distinct t1.b) as sum from t1,t2 where t1.a=t2.a and t2.b > 0 an
2 2
1 2
drop table t1,t2,t3;
create table t2 (a int, b int);
create table t3 (a int);
insert into t3 values (6),(7),(3);
select * from t3 where a >= all (select b from t2);
a
6
7
3
explain select * from t3 where a >= all (select b from t2);
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t3 ALL NULL NULL NULL NULL 3 Using where
2 SUBQUERY t2 system NULL NULL NULL NULL 0 const row not found
drop table if exists t2, t3;

14
mysql-test/t/subselect.test
View File

@ -100,6 +100,7 @@ insert into t2 values (100, 5);
select * from t3 where a < any (select b from t2);
select * from t3 where a < all (select b from t2);
select * from t3 where a >= any (select b from t2);
explain select * from t3 where a >= any (select b from t2);
select * from t3 where a >= all (select b from t2);
delete from t2 where a=100;
-- error 1239
@ -854,6 +855,7 @@ select * from t2 where t2.a in (select a from t1 where t1.b <> 30);
select * from t2 where t2.a in (select a from t1 where t1.b <> 30 and t1.b <> 31);
explain select * from t2 where t2.a in (select a from t1 where t1.b <> 30);
drop table t1, t2, t3;
#
# alloc_group_fields() working
#
@ -864,4 +866,14 @@ insert into t1 values (0,100),(1,2), (1,3), (2,2), (2,7), (2,-1), (3,10);
insert into t2 values (0,0), (1,1), (2,1), (3,1), (4,1);
insert into t3 values (3,3), (2,2), (1,1);
select a,(select count(distinct t1.b) as sum from t1,t2 where t1.a=t2.a and t2.b > 0 and t1.a <= t3.b group by t1.a order by sum limit 1) from t3;
drop table t1,t2,t3;s
drop table t1,t2,t3;
#
# correct ALL optimisation
#
create table t2 (a int, b int);
create table t3 (a int);
insert into t3 values (6),(7),(3);
select * from t3 where a >= all (select b from t2);
explain select * from t3 where a >= all (select b from t2);
drop table if exists t2, t3;