set @old_concurrent_insert= @@global.concurrent_insert;
set @@global.concurrent_insert= 0;
SET @old_log_output = @@global.log_output;
SET GLOBAL LOG_OUTPUT = 'FILE';
flush status;
show status like 'Table_lock%';
Variable_name	Value
Table_locks_immediate	1
Table_locks_waited	0
select * from performance_schema.session_status where variable_name like 'Table_lock%';
VARIABLE_NAME	VARIABLE_VALUE
Table_locks_immediate	2
Table_locks_waited	0
set sql_log_bin=0;
set @old_general_log = @@global.general_log;
set global general_log = 'OFF';
drop table if exists t1;
create table t1(n int);
insert into t1 values(1);
select get_lock('mysqltest_lock', 100);
get_lock('mysqltest_lock', 100)
1
# Switched to connection: con2
# Sending:
update t1 set n = get_lock('mysqltest_lock', 100) ;
# Switched to connection: con1
# Wait for the first UPDATE to get blocked.
# Sending:
update t1 set n = 3;
# Switched to connection: default
# wait for the second UPDATE to get blocked
Timeout in wait_condition.inc for select 1 from INFORMATION_SCHEMA.PROCESSLIST
where ID = (select connection_id()) and STATE = "Waiting for table level lock"
select release_lock('mysqltest_lock');
release_lock('mysqltest_lock')
1
# Switched to connection: con2
# Reaping first UPDATE
select release_lock('mysqltest_lock');
release_lock('mysqltest_lock')
1
# Switched to connection: con1
# Reaping second UPDATE
show status like 'Table_locks_waited';
Variable_name	Value
Table_locks_waited	0
# Switched to connection: default
drop table t1;
set global general_log = @old_general_log;
select 1;
1
1
show status like 'last_query_cost';
Variable_name	Value
Last_query_cost	0.000000
create table t1 (a int);
insert into t1 values (1),(2),(3),(4),(5),(6),(7),(8),(9),(10);
insert into t1 values (1),(2),(3),(4),(5),(6),(7),(8),(9),(10);
insert into t1 values (1),(2),(3),(4),(5),(6),(7),(8),(9),(10);
insert into t1 values (1),(2),(3),(4),(5),(6),(7),(8),(9),(10);
insert into t1 values (1),(2),(3),(4),(5),(6),(7),(8),(9),(10);
analyze table t1;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	OK
select * from t1 where a=6;
a
6
6
6
6
6
show status like 'last_query_cost';
Variable_name	Value
Last_query_cost	5.249000
show status like 'last_query_cost';
Variable_name	Value
Last_query_cost	5.249000
select 1;
1
1
show status like 'last_query_cost';
Variable_name	Value
Last_query_cost	0.000000
drop table t1;
FLUSH STATUS;
SHOW STATUS LIKE 'max_used_connections';
Variable_name	Value
Max_used_connections	1
SELECT * FROM performance_schema.session_status WHERE VARIABLE_NAME LIKE 'max_used_connections';
VARIABLE_NAME	VARIABLE_VALUE
Max_used_connections	1
SET @save_thread_cache_size=@@thread_cache_size;
SET GLOBAL thread_cache_size=3;
SHOW STATUS LIKE 'max_used_connections';
Variable_name	Value
Max_used_connections	3
SELECT * FROM performance_schema.session_status WHERE VARIABLE_NAME LIKE 'max_used_connections';
VARIABLE_NAME	VARIABLE_VALUE
Max_used_connections	3
FLUSH STATUS;
SHOW STATUS LIKE 'max_used_connections';
Variable_name	Value
Max_used_connections	2
SELECT * FROM performance_schema.session_status WHERE VARIABLE_NAME LIKE 'max_used_connections';
VARIABLE_NAME	VARIABLE_VALUE
Max_used_connections	2
SHOW STATUS LIKE 'max_used_connections';
Variable_name	Value
Max_used_connections	3
SELECT * FROM performance_schema.session_status WHERE VARIABLE_NAME LIKE 'max_used_connections';
VARIABLE_NAME	VARIABLE_VALUE
Max_used_connections	3
SHOW STATUS LIKE 'max_used_connections';
Variable_name	Value
Max_used_connections	4
SELECT * FROM performance_schema.session_status WHERE VARIABLE_NAME LIKE 'max_used_connections';
VARIABLE_NAME	VARIABLE_VALUE
Max_used_connections	4
SET GLOBAL thread_cache_size=@save_thread_cache_size;
CREATE TABLE t1 ( a INT );
INSERT INTO t1 VALUES (1), (2);
analyze table t1;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	OK
SELECT a FROM t1 LIMIT 1;
a
1
SHOW SESSION STATUS LIKE 'Last_query_cost';
Variable_name	Value
Last_query_cost	0.449000
EXPLAIN SELECT a FROM t1;
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	SIMPLE	t1	NULL	ALL	NULL	NULL	NULL	NULL	2	100.00	NULL
Warnings:
Note	1003	/* select#1 */ select `test`.`t1`.`a` AS `a` from `test`.`t1`
SHOW SESSION STATUS LIKE 'Last_query_cost';
Variable_name	Value
Last_query_cost	0.449000
SELECT a FROM t1 UNION SELECT a FROM t1 ORDER BY a;
a
1
2
SHOW SESSION STATUS LIKE 'Last_query_cost';
Variable_name	Value
Last_query_cost	0.898000
EXPLAIN SELECT a FROM t1 UNION SELECT a FROM t1 ORDER BY a;
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	PRIMARY	t1	NULL	ALL	NULL	NULL	NULL	NULL	2	100.00	NULL
2	UNION	t1	NULL	ALL	NULL	NULL	NULL	NULL	2	100.00	NULL
3	UNION RESULT	<union1,2>	NULL	ALL	NULL	NULL	NULL	NULL	NULL	NULL	Using temporary; Using filesort
Warnings:
Note	1003	/* select#1 */ select `test`.`t1`.`a` AS `a` from `test`.`t1` union /* select#2 */ select `test`.`t1`.`a` AS `a` from `test`.`t1` order by `a`
SHOW SESSION STATUS LIKE 'Last_query_cost';
Variable_name	Value
Last_query_cost	0.898000
SELECT a IN (SELECT a FROM t1) FROM t1 LIMIT 1;
a IN (SELECT a FROM t1)
1
SHOW SESSION STATUS LIKE 'Last_query_cost';
Variable_name	Value
Last_query_cost	0.898000
SELECT (SELECT a FROM t1 LIMIT 1) x FROM t1 LIMIT 1;
x
1
SHOW SESSION STATUS LIKE 'Last_query_cost';
Variable_name	Value
Last_query_cost	0.898000
SELECT * FROM t1 a, t1 b ORDER BY a.a, b.a LIMIT 1;
a	a
1	1
SHOW SESSION STATUS LIKE 'Last_query_cost';
Variable_name	Value
Last_query_cost	1.099010
DROP TABLE t1;
flush status;
show status like 'Com%function';
Variable_name	Value
Com_alter_function	0
Com_create_function	0
Com_drop_function	0
create function f1 (x INTEGER) returns integer
begin
declare ret integer;
set ret = x * 10;
return ret;
end //
drop function f1;
show status like 'Com%function';
Variable_name	Value
Com_alter_function	0
Com_create_function	1
Com_drop_function	1
create database db37908;
create table db37908.t1(f1 int);
insert into db37908.t1 values(1);
create user mysqltest_1@localhost;
grant usage,execute on test.* to mysqltest_1@localhost;
create procedure proc37908() begin select 1; end |
create function func37908() returns int sql security invoker
return (select * from db37908.t1 limit 1)|
select * from db37908.t1;
ERROR 42000: SELECT command denied to user 'mysqltest_1'@'localhost' for table 't1'
show status where variable_name ='uptime' and 2 in (select * from db37908.t1);
ERROR 42000: SELECT command denied to user 'mysqltest_1'@'localhost' for table 't1'
show procedure status where name ='proc37908' and 1 in (select f1 from db37908.t1);
ERROR 42000: SELECT command denied to user 'mysqltest_1'@'localhost' for table 't1'
show function status where name ='func37908' and 1 in (select func37908());
ERROR 42000: SELECT command denied to user 'mysqltest_1'@'localhost' for table 't1'
drop database db37908;
drop procedure proc37908;
drop function func37908;
REVOKE ALL PRIVILEGES, GRANT OPTION FROM mysqltest_1@localhost;
DROP USER mysqltest_1@localhost;
DROP PROCEDURE IF EXISTS p1;
DROP FUNCTION IF EXISTS f1;
CREATE FUNCTION f1() RETURNS INTEGER
BEGIN
DECLARE foo INTEGER;
DECLARE bar INTEGER;
SET foo=1;
SET bar=2;
RETURN foo;
END $$
CREATE PROCEDURE p1()
BEGIN
SELECT 1;
END $$
SELECT f1();
f1()
1
CALL p1();
1
1
SELECT 9;
9
9
DROP PROCEDURE p1;
DROP FUNCTION f1;
#
# Test coverage for status variables which were introduced by
# WL#5772 "Add partitioned Table Definition Cache to avoid
# using LOCK_open and its derivatives in DML queries".
#
create table t1 (i int);
create table t2 (j int);
create table t3 (k int);
# Flush table cache to ensure that it is empty and reset status
# variables. Since to test cache overflow we will need to reduce
# its size, also save original table cache size.
flush tables;
flush status;
set @old_table_open_cache= @@table_open_cache;
# Check that after reset all status variables are zero.
show status like 'table_open_cache_%';
Variable_name	Value
Table_open_cache_hits	0
Table_open_cache_misses	0
Table_open_cache_overflows	0
# The first statement accessing t1 after flush should result
# in table cache miss.
select * from t1;
i
show status like 'table_open_cache_%';
Variable_name	Value
Table_open_cache_hits	1
Table_open_cache_misses	16
Table_open_cache_overflows	0
# The second statement accessing the same table should
# result in table cache hit.
select * from t1;
i
show status like 'table_open_cache_%';
Variable_name	Value
Table_open_cache_hits	2
Table_open_cache_misses	16
Table_open_cache_overflows	0
# Again table cache miss if accessing different table.
select * from t2;
j
show status like 'table_open_cache_%';
Variable_name	Value
Table_open_cache_hits	18
Table_open_cache_misses	17
Table_open_cache_overflows	0
# And cache hit then accessing it second time.
select * from t2;
j
show status like 'table_open_cache_%';
Variable_name	Value
Table_open_cache_hits	19
Table_open_cache_misses	17
Table_open_cache_overflows	0
# The below statement should result in 2 cache hits and 
# 4 cache misses since it needs 6 table instances in total.
select * from t1 as a, t2 as b, t1 as c, t2 as d, t1 as e, t2 as f;
i	j	i	j	i	j
show status like 'table_open_cache_%';
Variable_name	Value
Table_open_cache_hits	21
Table_open_cache_misses	21
Table_open_cache_overflows	0
# Reduce size of table cache to check that status
# variable tracking cache overflows works.
set @@global.table_open_cache= 4;
# The below statement should result in table cache hit, but
# as a side effect it should result in trimming of table
# cache by 2 TABLE instances, meaning that overflow counter
# will get increased by 2.
select * from t1;
i
show status like 'table_open_cache_%';
Variable_name	Value
Table_open_cache_hits	22
Table_open_cache_misses	21
Table_open_cache_overflows	19
# This statement should result in 4 cache hits, 2 cache misses/
# overflows.
select * from t1 as a, t2 as b, t1 as c, t2 as d, t1 as e, t2 as f;
i	j	i	j	i	j
show status like 'table_open_cache_%';
Variable_name	Value
Table_open_cache_hits	25
Table_open_cache_misses	24
Table_open_cache_overflows	22
# Finally, the below statement should result in 1 cache miss
# and 1 overflow since it accesses table which is not yet in
# cache and table cache is full.
select * from t3;
k
show status like 'table_open_cache_%';
Variable_name	Value
Table_open_cache_hits	25
Table_open_cache_misses	41
Table_open_cache_overflows	39
# Cleanup
set @@global.table_open_cache= @old_table_open_cache;
drop tables t1, t2, t3;
SHOW STATUS LIKE 'max_used_connections_time';
Variable_name	Value
Max_used_connections_time	DTVALUE
# Should report 4
SHOW STATUS LIKE 'max_used_connections';
Variable_name	Value
Max_used_connections	4
# Should report 4
SHOW STATUS LIKE 'max_used_connections';
Variable_name	Value
Max_used_connections	4
# This should report 0 as it must have the same value as above
TIMESTAMPDIFF(SECOND,'DTVALUE','DTVALUE') <> 0
0
# This should report 0 as timestamp is updated only when connection count strictly exceeds the previos highest value
TIMESTAMPDIFF(SECOND,'DTVALUE','DTVALUE') <> 0
0
FLUSH STATUS;
# This should not report 0 as FLUSH STATUS is called.
TIMESTAMPDIFF(SECOND,'DTVALUE','DTVALUE') <> 0
1
set @@global.concurrent_insert= @old_concurrent_insert;
SET GLOBAL log_output = 'FILE,TABLE';
#
# Bug#28786951 SET LAST_QUERY_COST FOR QUERIES WITH SUBQUERIES AND UNIONS
#
CREATE TABLE t1(x INT, y INT);
INSERT INTO t1 VALUES (1, 2), (3, 4), (5, 6);
ANALYZE TABLE t1;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	OK
EXPLAIN SELECT * FROM t1;
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	SIMPLE	t1	NULL	ALL	NULL	NULL	NULL	NULL	3	100.00	NULL
Warnings:
Note	1003	/* select#1 */ select `test`.`t1`.`x` AS `x`,`test`.`t1`.`y` AS `y` from `test`.`t1`
SHOW STATUS LIKE 'Last_query_cost';
Variable_name	Value
Last_query_cost	0.549000
EXPLAIN SELECT (SELECT MAX(x) FROM t1) FROM t1;
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	PRIMARY	t1	NULL	ALL	NULL	NULL	NULL	NULL	3	100.00	NULL
2	SUBQUERY	t1	NULL	ALL	NULL	NULL	NULL	NULL	3	100.00	NULL
Warnings:
Note	1003	/* select#1 */ select (/* select#2 */ select max(`test`.`t1`.`x`) from `test`.`t1`) AS `(SELECT MAX(x) FROM t1)` from `test`.`t1`
SHOW STATUS LIKE 'Last_query_cost';
Variable_name	Value
Last_query_cost	1.098000
EXPLAIN SELECT * FROM t1 WHERE x IN (SELECT MAX(x) FROM t1);
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	PRIMARY	t1	NULL	ALL	NULL	NULL	NULL	NULL	3	100.00	Using where
2	DEPENDENT SUBQUERY	t1	NULL	ALL	NULL	NULL	NULL	NULL	3	100.00	NULL
Warnings:
Note	1003	/* select#1 */ select `test`.`t1`.`x` AS `x`,`test`.`t1`.`y` AS `y` from `test`.`t1` where <in_optimizer>(`test`.`t1`.`x`,<exists>(/* select#2 */ select max(`test`.`t1`.`x`) from `test`.`t1` having (<cache>(`test`.`t1`.`x`) = <ref_null_helper>(max(`test`.`t1`.`x`)))))
SHOW STATUS LIKE 'Last_query_cost';
Variable_name	Value
Last_query_cost	2.196000
EXPLAIN SELECT /*+ NO_MERGE(a) */ * FROM (SELECT * FROM t1) a, t1 b;
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	PRIMARY	<derived2>	NULL	ALL	NULL	NULL	NULL	NULL	3	100.00	NULL
1	PRIMARY	b	NULL	ALL	NULL	NULL	NULL	NULL	3	100.00	Using join buffer (hash join)
2	DERIVED	t1	NULL	ALL	NULL	NULL	NULL	NULL	3	100.00	NULL
Warnings:
Note	1003	/* select#1 */ select /*+ NO_MERGE(`a`@`select#1`) */ `a`.`x` AS `x`,`a`.`y` AS `y`,`test`.`b`.`x` AS `x`,`test`.`b`.`y` AS `y` from (/* select#2 */ select `test`.`t1`.`x` AS `x`,`test`.`t1`.`y` AS `y` from `test`.`t1`) `a` join `test`.`t1` `b`
SHOW STATUS LIKE 'Last_query_cost';
Variable_name	Value
Last_query_cost	4.535526
EXPLAIN SELECT * FROM t1 WHERE x > 0;
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	SIMPLE	t1	NULL	ALL	NULL	NULL	NULL	NULL	3	33.33	Using where
Warnings:
Note	1003	/* select#1 */ select `test`.`t1`.`x` AS `x`,`test`.`t1`.`y` AS `y` from `test`.`t1` where (`test`.`t1`.`x` > 0)
SHOW STATUS LIKE 'Last_query_cost';
Variable_name	Value
Last_query_cost	0.549000
EXPLAIN SELECT * FROM t1 WHERE y > 0;
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	SIMPLE	t1	NULL	ALL	NULL	NULL	NULL	NULL	3	33.33	Using where
Warnings:
Note	1003	/* select#1 */ select `test`.`t1`.`x` AS `x`,`test`.`t1`.`y` AS `y` from `test`.`t1` where (`test`.`t1`.`y` > 0)
SHOW STATUS LIKE 'Last_query_cost';
Variable_name	Value
Last_query_cost	0.549000
EXPLAIN SELECT * FROM t1 WHERE x > 0
UNION ALL
SELECT * FROM t1 WHERE y > 0;
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	PRIMARY	t1	NULL	ALL	NULL	NULL	NULL	NULL	3	33.33	Using where
2	UNION	t1	NULL	ALL	NULL	NULL	NULL	NULL	3	33.33	Using where
Warnings:
Note	1003	/* select#1 */ select `test`.`t1`.`x` AS `x`,`test`.`t1`.`y` AS `y` from `test`.`t1` where (`test`.`t1`.`x` > 0) union all /* select#2 */ select `test`.`t1`.`x` AS `x`,`test`.`t1`.`y` AS `y` from `test`.`t1` where (`test`.`t1`.`y` > 0)
SHOW STATUS LIKE 'Last_query_cost';
Variable_name	Value
Last_query_cost	1.098000
EXPLAIN SELECT * FROM t1 WHERE x > 0
UNION DISTINCT
SELECT * FROM t1 WHERE y > 0;
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	PRIMARY	t1	NULL	ALL	NULL	NULL	NULL	NULL	3	33.33	Using where
2	UNION	t1	NULL	ALL	NULL	NULL	NULL	NULL	3	33.33	Using where
3	UNION RESULT	<union1,2>	NULL	ALL	NULL	NULL	NULL	NULL	NULL	NULL	Using temporary
Warnings:
Note	1003	/* select#1 */ select `test`.`t1`.`x` AS `x`,`test`.`t1`.`y` AS `y` from `test`.`t1` where (`test`.`t1`.`x` > 0) union /* select#2 */ select `test`.`t1`.`x` AS `x`,`test`.`t1`.`y` AS `y` from `test`.`t1` where (`test`.`t1`.`y` > 0)
SHOW STATUS LIKE 'Last_query_cost';
Variable_name	Value
Last_query_cost	1.098000
EXPLAIN INSERT INTO t1 SELECT * FROM t1;
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	INSERT	t1	NULL	ALL	NULL	NULL	NULL	NULL	NULL	NULL	NULL
1	SIMPLE	t1	NULL	ALL	NULL	NULL	NULL	NULL	3	100.00	Using temporary
Warnings:
Note	1003	insert into `test`.`t1` /* select#1 */ select sql_buffer_result `test`.`t1`.`x` AS `x`,`test`.`t1`.`y` AS `y` from `test`.`t1`
SHOW STATUS LIKE 'Last_query_cost';
Variable_name	Value
Last_query_cost	0.549000
EXPLAIN INSERT INTO t1
SELECT * FROM t1 WHERE x > 0
UNION ALL
SELECT * FROM t1 WHERE y > 0;
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	INSERT	t1	NULL	ALL	NULL	NULL	NULL	NULL	NULL	NULL	NULL
1	PRIMARY	t1	NULL	ALL	NULL	NULL	NULL	NULL	3	33.33	Using where
2	UNION	t1	NULL	ALL	NULL	NULL	NULL	NULL	3	33.33	Using where
3	UNION RESULT	<union1,2>	NULL	ALL	NULL	NULL	NULL	NULL	NULL	NULL	Using temporary
Warnings:
Note	1003	insert into `test`.`t1` /* select#1 */ select `test`.`t1`.`x` AS `x`,`test`.`t1`.`y` AS `y` from `test`.`t1` where (`test`.`t1`.`x` > 0) union all /* select#2 */ select `test`.`t1`.`x` AS `x`,`test`.`t1`.`y` AS `y` from `test`.`t1` where (`test`.`t1`.`y` > 0)
SHOW STATUS LIKE 'Last_query_cost';
Variable_name	Value
Last_query_cost	1.098000
EXPLAIN INSERT INTO t1
SELECT * FROM t1 WHERE x > 0
UNION DISTINCT
SELECT * FROM t1 WHERE y > 0;
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	INSERT	t1	NULL	ALL	NULL	NULL	NULL	NULL	NULL	NULL	NULL
1	PRIMARY	t1	NULL	ALL	NULL	NULL	NULL	NULL	3	33.33	Using where
2	UNION	t1	NULL	ALL	NULL	NULL	NULL	NULL	3	33.33	Using where
3	UNION RESULT	<union1,2>	NULL	ALL	NULL	NULL	NULL	NULL	NULL	NULL	Using temporary
Warnings:
Note	1003	insert into `test`.`t1` /* select#1 */ select `test`.`t1`.`x` AS `x`,`test`.`t1`.`y` AS `y` from `test`.`t1` where (`test`.`t1`.`x` > 0) union /* select#2 */ select `test`.`t1`.`x` AS `x`,`test`.`t1`.`y` AS `y` from `test`.`t1` where (`test`.`t1`.`y` > 0)
SHOW STATUS LIKE 'Last_query_cost';
Variable_name	Value
Last_query_cost	1.098000
DROP TABLE t1;
#
# Bug#28884359: LAST_QUERY_COST IS NEGATIVE AFTER ORDER BY/LIMIT QUERY
#
CREATE TABLE t1 (pk INTEGER PRIMARY KEY,
i1 INTEGER,
i2 INTEGER NOT NULL,
INDEX k1 (i1),
INDEX k2 (i1, i2));
INSERT INTO t1 VALUES
(1, NULL, 43), (11, NULL, 103), (10, 32,50), (9, 12, 43),
(8, NULL, 13), (7, 48, 90), (6, 56, 90), (5, 87, 84),
(4, 58, 98), (3, 30, 82), (2, 54, 57), (12, 232, 43),
(13, 43, 103), (14, 32, 45), (15, 12, 43), (16, 89, 23),
(17, 48, 90), (18, 56, 90), (19, 87, 84);
CREATE TABLE t2 (pk INTEGER PRIMARY KEY,
i1 INTEGER NOT NULL,
INDEX k1 (i1));
INSERT INTO t2 VALUES
(3, 89), (4, 98), (5, 84), (6, 8), (7, 99), (8, 110),
(9, 84), (10, 98), (11, 103), (12, 50), (13, 84),
(14, 57), (15, 82), (16, 103), (2, 98), (1, 90);
ANALYZE TABLE t1, t2;
Table	Op	Msg_type	Msg_text
test.t1	analyze	status	OK
test.t2	analyze	status	OK
EXPLAIN SELECT * FROM t1, t2 WHERE t1.i1 = t2.i1 ORDER BY t1.i1 LIMIT 10;
id	select_type	table	partitions	type	possible_keys	key	key_len	ref	rows	filtered	Extra
1	SIMPLE	t1	NULL	index	k1,k2	k2	9	NULL	10	100.00	Using where; Using index
1	SIMPLE	t2	NULL	ref	k1	k1	4	test.t1.i1	1	100.00	Using index
Warnings:
Note	1003	/* select#1 */ select `test`.`t1`.`pk` AS `pk`,`test`.`t1`.`i1` AS `i1`,`test`.`t1`.`i2` AS `i2`,`test`.`t2`.`pk` AS `pk`,`test`.`t2`.`i1` AS `i1` from `test`.`t1` join `test`.`t2` where (`test`.`t2`.`i1` = `test`.`t1`.`i1`) order by `test`.`t1`.`i1` limit 10
SHOW STATUS LIKE 'Last_query_cost';
Variable_name	Value
Last_query_cost	9.664743
DROP TABLE t1, t2;
SET @@global.log_output = @old_log_output;
SET @@global.general_log = @old_general_log;
TRUNCATE TABLE mysql.general_log;