MySql慢查询日志——开启/查看/删除

1,开启慢查询日志

修改mysql.ini文件，加入如下配置：

[mysqld]
log-slow-queries=H:\mysql_log\slow_query.log
long-query-time=3

set global slow_query_log=ON;

set global slow_launch_time=5;

show variables like "%slow%";

设置查询日志的存储位置，慢查询时间。

show variables like '%slow%'; /*查看慢查询配置*/

show variables like "long_query_time"; /*查看慢查询时间*/

show status like "%slow_queries%";/*查看慢查询配置情况*/

2，查看慢查询

打开log文件：

F:\mysql\bin\mysqld, Version: 5.5.24-log (MySQL Community Server (GPL)). started with:
TCP Port: 3306, Named Pipe: (null)
Time                 Id Command    Argument
# Time: 161008 21:20:02
# User@Host: root[root] @ localhost [127.0.0.1]
# Query_time: 8.718499  Lock_time: 0.001002 Rows_sent: 0  Rows_examined: 908972
use energy;
SET timestamp=1475932802;
/*结束时间*/

select 

DATE_FORMAT(worker_order.create_time,'%Y-%m-%d') as create_time,/*创建时间*/
(	select count(0)
		from biz_work_order tmp
		where
		DATE_FORMAT(tmp.create_time,'%Y-%m-%d')=DATE_FORMAT(worker_order.create_time,'%Y-%m-%d')
		or (tmp.create_time<DATE_FORMAT(worker_order.create_time,'%Y-%m-%d') and tmp.`status` in (1,2,4))
	)as should_change_worker_order

from biz_work_order worker_order 

WHERE
				(CASE  WHEN IFNULL(@belongCity,'0')='0' OR @belongCity=''  THEN  1 ELSE   

        CAST(LOCATE(@belongCity,worker_order.belong_city) AS SIGNED )   

        END)=1
AND

	(CASE  WHEN IFNULL(@energyStation,'0')='0'  THEN  1 ELSE   

        CAST(LOCATE(@energyStation,worker_order.repository_id) AS SIGNED )   

        END)=1
AND
	(CASE  WHEN IFNULL(@serviceStatioin,'0')='0'  THEN  1 ELSE   

        CAST(LOCATE(@serviceStatioin,worker_order.station_id) AS SIGNED )   

        END)=1
AND
				DATE_FORMAT(worker_order.create_time, '%Y-%m-%d') BETWEEN DATE_FORMAT(cast(@beginDateTime as datetime), '%Y-%m-%d') and DATE_FORMAT(cast(@endDateTime as datetime), '%Y-%m-%d')

GROUP BY DATE_FORMAT(worker_order.create_time,'%Y-%m-%d');
# Time: 161008 21:20:40
# User@Host: root[root] @ localhost [127.0.0.1]
# Query_time: 33.695952  Lock_time: 0.000000 Rows_sent: 0  Rows_examined: 3239812
SET timestamp=1475932840;
/*结束时间*/

select 

DATE_FORMAT(worker_order.create_time,'%Y-%m-%d') as create_time,/*创建时间*/
(	select count(0)
		from biz_work_order tmp
		where
		DATE_FORMAT(tmp.create_time,'%Y-%m-%d')=DATE_FORMAT(worker_order.create_time,'%Y-%m-%d')
		or (tmp.create_time<DATE_FORMAT(worker_order.create_time,'%Y-%m-%d') and tmp.`status` in (1,2,4))
	)as should_change_worker_order

from biz_work_order worker_order 

WHERE
				(CASE  WHEN IFNULL(@belongCity,'0')='0' OR @belongCity=''  THEN  1 ELSE   

        CAST(LOCATE(@belongCity,worker_order.belong_city) AS SIGNED )   

        END)=1
AND

	(CASE  WHEN IFNULL(@energyStation,'0')='0'  THEN  1 ELSE   

        CAST(LOCATE(@energyStation,worker_order.repository_id) AS SIGNED )   

        END)=1
AND
	(CASE  WHEN IFNULL(@serviceStatioin,'0')='0'  THEN  1 ELSE   

        CAST(LOCATE(@serviceStatioin,worker_order.station_id) AS SIGNED )   

        END)=1
AND
				DATE_FORMAT(worker_order.create_time, '%Y-%m-%d') BETWEEN DATE_FORMAT(cast(@beginDateTime as datetime), '%Y-%m-%d') and DATE_FORMAT(cast(@endDateTime as datetime), '%Y-%m-%d')

GROUP BY DATE_FORMAT(worker_order.create_time,'%Y-%m-%d');
# Time: 161008 21:21:49
# User@Host: root[root] @ localhost [127.0.0.1]
# Query_time: 48.615826  Lock_time: 0.000000 Rows_sent: 0  Rows_examined: 4920668
SET timestamp=1475932909;
/*结束时间*/

select 

DATE_FORMAT(worker_order.create_time,'%Y-%m-%d') as create_time,/*创建时间*/
(	select count(0)
		from biz_work_order tmp
		where
		DATE_FORMAT(tmp.create_time,'%Y-%m-%d')=DATE_FORMAT(worker_order.create_time,'%Y-%m-%d')
		or (tmp.create_time<DATE_FORMAT(worker_order.create_time,'%Y-%m-%d') and tmp.`status` in (1,2,4))
	)as should_change_worker_order

from biz_work_order worker_order 

WHERE
				(CASE  WHEN IFNULL(@belongCity,'0')='0' OR @belongCity=''  THEN  1 ELSE   

        CAST(LOCATE(@belongCity,worker_order.belong_city) AS SIGNED )   

        END)=1
AND

	(CASE  WHEN IFNULL(@energyStation,'0')='0'  THEN  1 ELSE   

        CAST(LOCATE(@energyStation,worker_order.repository_id) AS SIGNED )   

        END)=1
AND
	(CASE  WHEN IFNULL(@serviceStatioin,'0')='0'  THEN  1 ELSE   

        CAST(LOCATE(@serviceStatioin,worker_order.station_id) AS SIGNED )   

        END)=1
AND
				DATE_FORMAT(worker_order.create_time, '%Y-%m-%d') BETWEEN DATE_FORMAT(cast(@beginDateTime as datetime), '%Y-%m-%d') and DATE_FORMAT(cast(@endDateTime as datetime), '%Y-%m-%d')

GROUP BY DATE_FORMAT(worker_order.create_time,'%Y-%m-%d');
# Time: 161008 21:22:37
# User@Host: root[root] @ localhost [127.0.0.1]
# Query_time: 41.309375  Lock_time: 0.000000 Rows_sent: 0  Rows_examined: 6050268
SET timestamp=1475932957;
call Pro_query_work_order_report('50010',NULL,270,date_sub(curdate(), INTERVAL 6 DAY),curdate());
# Time: 161008 21:23:59
# User@Host: root[root] @ localhost [127.0.0.1]
# Query_time: 79.538506  Lock_time: 0.000000 Rows_sent: 7  Rows_examined: 12282968
SET timestamp=1475933039;
call Pro_query_work_order_report('50010',NULL,270,date_sub(curdate(), INTERVAL 6 DAY),curdate());

被自己写的SQL慢哭了。。。

三，删除慢查询日志

直接delete掉log,删除后需要执行下面两句中的任意一句，重新生成日志文件：

  -> mysqladmin -u root-p flush-logs
    -> flush logs