database/mariadb
1
0
Fork 0
mirror of https://github.com/MariaDB/server.git synced 2025-11-28 17:36:30 +03:00
Code Activity

Fixed bug mdev-4418.

Browse Source 
After single row substitutions there might appear new equalities.
They should be properly propagated to all AND/OR levels the WHERE
condition. It's done now with an additional call of remove_eq_conds().
This commit is contained in:
Igor Babaev
2013-08-16 22:01:47 -07:00
parent 752d5d022d
commit 25c152018d
14 changed files with 98 additions and 10 deletions
Download Patch File Download Diff File Expand all files Collapse all files

4
mysql-test/r/table_elim.result
View File

@@ -17,7 +17,7 @@ explain extended select t1.a from t1 left join t2 on t2.a=t1.a;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 4 100.00
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1` where 1
Note 1003 select `test`.`t1`.`a` AS `a` from `test`.`t1`
select t1.a from t1 left join t2 on t2.a=t1.a;
a
0
@@ -62,7 +62,7 @@ id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t0 ALL NULL NULL NULL NULL 4 100.00
1 SIMPLE t1 ALL NULL NULL NULL NULL 4 100.00 Using where
Warnings:
Note 1003 select `test`.`t0`.`a` AS `a` from `test`.`t0` left join (`test`.`t1`) on((`test`.`t1`.`a` = `test`.`t0`.`a`)) where 1
Note 1003 select `test`.`t0`.`a` AS `a` from `test`.`t0` left join (`test`.`t1`) on((`test`.`t1`.`a` = `test`.`t0`.`a`))
# Elimination with aggregate functions
explain select count(*) from t1 left join t2 on t2.a=t1.a;
id select_type table type possible_keys key key_len ref rows Extra