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MDEV-15253: Default optimizer setting changes for MariaDB 10.4

use_stat_tables= PREFERABLY
optimizer_use_condition_selectivity= 4
This commit is contained in:
Varun Gupta
2018-05-31 15:51:59 +05:30
committed by Varun Gupta
parent a25ce5ab4b
commit 93c360e3a5
248 changed files with 3685 additions and 1747 deletions

View File

@ -6,6 +6,7 @@ insert t1 select 2,seq from seq_1_to_50;
insert t1 select 3,seq from seq_1_to_20;
analyze table t1;
Table Op Msg_type Msg_text
test.t1 analyze status Engine-independent statistics collected
test.t1 analyze status OK
#
# Delete with limit (quick select - range acces)
@ -47,8 +48,8 @@ rollback;
start transaction;
explain delete from v1 where (select count(*) from t1 b where b.c1=v1.c1) = 500 limit 1;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 ALL c1 NULL NULL NULL 502 Using where
2 DEPENDENT SUBQUERY b ref c1 c1 4 test.t1.c1 58 Using index
1 PRIMARY t1 range c1 c1 4 NULL 600 Using where
2 DEPENDENT SUBQUERY b ref c1 c1 4 test.t1.c1 167 Using index
delete from v1 where (select count(*) from t1 b where b.c1=v1.c1) = 500 limit 1;
affected rows: 1
delete from v1 where (select count(*) from t1 b where b.c1=v1.c1) = 500 limit 1;
@ -63,8 +64,8 @@ rollback;
start transaction;
explain delete from v1 where (select count(*) from t1 b where b.c1=v1.c1) = 500;
id select_type table type possible_keys key key_len ref rows Extra
1 PRIMARY t1 ALL c1 NULL NULL NULL 502 Using where
2 DEPENDENT SUBQUERY b ref c1 c1 4 test.t1.c1 58 Using index
1 PRIMARY t1 ALL c1 NULL NULL NULL 670 Using where
2 DEPENDENT SUBQUERY b ref c1 c1 4 test.t1.c1 167 Using index
delete from v1 where (select count(*) from t1 b where b.c1=v1.c1) = 500 ;
affected rows: 500
select count(*) from v1 where c1=0;