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MDEV-21472: ALTER TABLE ... ANALYZE PARTITION ... with EITS reads and locks all rows

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Do not collect EITS statistics for this statement:

  ALTER TABLE t ANALYZE PARTITION p

EITS stats are currently global, not per-partition.
Collecting global stats when we are asked to process just one partition
causes issues for DBAs.
This commit is contained in:
Sergei Petrunia 2020-07-29 23:26:09 +03:00
parent e54a7ac1b3
commit 7e9ffc69ec
4 changed files with 71 additions and 4 deletions
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34
mysql-test/r/stat_tables_partition.result
View File

@ -9,5 +9,37 @@ ANALYZE TABLE t1;
Table Op Msg_type Msg_text
test.t1 analyze status Engine-independent statistics collected
test.t1 analyze status OK
SET use_stat_tables = DEFAULT;
DROP TABLE t1;
#
# MDEV-21472: ALTER TABLE ... ANALYZE PARTITION ... with EITS reads and locks all rows
#
CREATE TABLE t1 (
id int(11) auto_increment primary key,
c1 int(11) DEFAULT NULL
) PARTITION BY RANGE (id) (
PARTITION p0 VALUES LESS THAN (4),
PARTITION p1 VALUES LESS THAN MAXVALUE
);
insert into t1(c1) values (1),(1),(1),(1), (1),(1),(1),(1);
insert into t1(c1) select c1 from t1;
insert into t1(c1) select c1 from t1;
select count(*) from t1;
count(*)
32
select count(*) from t1 where id <4;
count(*)
3
flush status;
set session use_stat_tables='preferably';
# Must NOT show "Engine-independent statistics collected":
alter table t1 analyze partition p0;
Table Op Msg_type Msg_text
test.t1 analyze status OK
# Should not have Handler_read_rnd_next=34
show session status like 'Handler_read_rnd%';
Variable_name Value
Handler_read_rnd 0
Handler_read_rnd_deleted 0
Handler_read_rnd_next 0
drop table t1;
SET use_stat_tables = DEFAULT;

1
mysql-test/r/stat_tables_rbr.result
View File

@ -13,7 +13,6 @@ SET use_stat_tables = PREFERABLY;
CREATE TABLE t1 ( a INT ) ENGINE=MyISAM PARTITION BY HASH(a) PARTITIONS 2;
ALTER TABLE t1 ANALYZE PARTITION p1;
Table Op Msg_type Msg_text
test.t1 analyze status Engine-independent statistics collected
test.t1 analyze status OK
include/show_binlog_events.inc
Log_name Pos Event_type Server_id End_log_pos Info

30
mysql-test/t/stat_tables_partition.test
View File

@ -11,7 +11,33 @@ CREATE TABLE t1 (pk int PRIMARY KEY, a bit(1), INDEX idx(a)
INSERT INTO t1 VALUES (1,1),(2,0),(3,0),(4,1);
ANALYZE TABLE t1;
DROP TABLE t1;
--echo #
--echo # MDEV-21472: ALTER TABLE ... ANALYZE PARTITION ... with EITS reads and locks all rows
--echo #
CREATE TABLE t1 (
id int(11) auto_increment primary key,
c1 int(11) DEFAULT NULL
) PARTITION BY RANGE (id) (
PARTITION p0 VALUES LESS THAN (4),
PARTITION p1 VALUES LESS THAN MAXVALUE
);
insert into t1(c1) values (1),(1),(1),(1), (1),(1),(1),(1);
insert into t1(c1) select c1 from t1;
insert into t1(c1) select c1 from t1;
select count(*) from t1;
select count(*) from t1 where id <4;
flush status;
set session use_stat_tables='preferably';
--echo # Must NOT show "Engine-independent statistics collected":
alter table t1 analyze partition p0;
--echo # Should not have Handler_read_rnd_next=34
show session status like 'Handler_read_rnd%';
drop table t1;
SET use_stat_tables = DEFAULT;
DROP TABLE t1;

10
sql/sql_admin.cc
View File

@ -727,8 +727,18 @@ static bool mysql_admin_table(THD* thd, TABLE_LIST* tables,
{
compl_result_code= result_code= HA_ADMIN_INVALID;
}
/*
The check for Alter_info::ALTER_ADMIN_PARTITION implements this logic:
do not collect EITS STATS for this syntax:
ALTER TABLE ... ANALYZE PARTITION p
EITS statistics is global (not per-partition). Collecting global stats
is much more expensive processing just one partition, so the most
appropriate action is to just not collect EITS stats for this command.
*/
collect_eis=
(table->table->s->table_category == TABLE_CATEGORY_USER &&
!(lex->alter_info.flags &= Alter_info::ALTER_ADMIN_PARTITION) &&
(get_use_stat_tables_mode(thd) > NEVER ||
lex->with_persistent_for_clause));