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Merge 10.2 into 10.3

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Marko Mäkelä
2019-08-21 15:23:45 +03:00
parent e8de75db88 9de2e60d74
commit 32ec5fb979
50 changed files with 1382 additions and 334 deletions
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34
mysql-test/main/selectivity.result
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@@ -1635,3 +1635,37 @@ set @@use_stat_tables= @save_use_stat_tables;
set @@optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity;
drop table t1;
drop function f1;
#
# MDEV-19834 Selectivity of an equality condition discounted twice
#
set @@optimizer_use_condition_selectivity=4;
set @@use_stat_tables='preferably';
create table t1 (a int, b int, key (b), key (a));
insert into t1
select (rand(1)*1000)/10, (rand(1001)*1000)/50 from seq_1_to_1000;
analyze table t1 ;
Table Op Msg_type Msg_text
test.t1 analyze status Engine-independent statistics collected
test.t1 analyze status Table is already up to date
# Check what info the optimizer has about selectivities
explain extended select * from t1 use index () where a in (17,51,5);
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 1000 2.97 Using where
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1` USE INDEX () where `test`.`t1`.`a` in (17,51,5)
explain extended select * from t1 use index () where b=2;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 ALL NULL NULL NULL NULL 1000 4.76 Using where
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1` USE INDEX () where `test`.`t1`.`b` = 2
# Now, the equality is used for ref access, while the range condition
# gives selectivity data
explain extended select * from t1 where a in (17,51,5) and b=2;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE t1 ref b,a b 5 const 58 2.90 Using where
Warnings:
Note 1003 select `test`.`t1`.`a` AS `a`,`test`.`t1`.`b` AS `b` from `test`.`t1` where `test`.`t1`.`b` = 2 and `test`.`t1`.`a` in (17,51,5)
drop table t1;
set use_stat_tables= @save_use_stat_tables;
set optimizer_use_condition_selectivity=@save_optimizer_use_condition_selectivity;
# End of 10.1 tests