mysql的定时任务一般用event(事件)来完成,触发器无法完成。
一、通过mysql的命令行客户端来完成
1、set global event_scheduler =1; //开启event_scheduler
执行这个语句如果出现,可在mysql的配置文档中设置
[mysqld]段中添加 event_scheduler=ON
如果重启mysql;这种情况下依然出错,
Error Code: 1290. The MySQL server is running with the --event-scheduler=DISABLED
or --skip-grant-tables option so it cannot execute this statement,这个错误是说启动服务器时如果指定了--skip-grant-tables选项,则event_scheduler则自动被设置为DISABLED。命令行或配置文件的设置都会被覆盖。建议重现安装mysql或是修改启动参数(在系统服务中指定)。查看event_scheduler状态:show status like '%event%'; 或SELECT @@event_scheduler;
2、CREATE PROCEDURE Mypro() //创建存储过程
BEGIN
update userinfo SET endtime = now() WHERE id = '155';
END;
3、创建event My_enevt,每隔三十秒执行一次
create event if not exists e_test
on schedule every 30 second
on completion preserve
do call Mypro();
4、关闭事件
alter event e_test ON COMPLETION PRESERVE DISABLE;
5、开启事件
alter event e_test ON COMPLETION PRESERVE ENABLE;
语法:
CREATE EVENT [IF NOT EXISTS] event_name ON SCHEDULE schedule [ON COMPLETION
[NOT] PRESERVE] [ENABLE | DISABLE] [COMMENT 'comment'] DO sql_statement;
schedule: AT TIMESTAMP [+ INTERVAL INTERVAL] | EVERY INTERVAL [STARTS TIMESTAMP]
[ENDS TIMESTAMP] INTERVAL: quantity {YEAR | QUARTER | MONTH | DAY | HOUR |
MINUTE | WEEK | SECOND | YEAR_MONTH | DAY_HOUR | DAY_MINUTE | DAY_SECOND |
HOUR_MINUTE | HOUR_SECOND | MINUTE_SECOND}
示例:
1) 首先来看一个简单的例子来演示每秒插入一条记录到数据表
CREATE EVENT e_test_insert ON SCHEDULE EVERY 1 SECOND DO INSERT INTO test.aaa VALUES (CURRENT_TIMESTAMP);
2) 5天后清空test表:
CREATE EVENT e_test ON SCHEDULE AT CURRENT_TIMESTAMP + INTERVAL 5 DAY DO TRUNCATE TABLE test.aaa;
3) 2013年7月20日12点整清空test表:
CREATE EVENT e_test ON SCHEDULE AT TIMESTAMP '2013-07-20 12:00:00' DOTRUNCATE TABLE test.aaa;
4) 每天定时清空test表:
CREATE EVENT e_test ON SCHEDULE EVERY 1 DAY DO TRUNCATE TABLE test.aaa;
5) 5天后开启每天定时清空test表:
CREATE EVENT e_test ON SCHEDULE EVERY 1 DAY STARTS CURRENT_TIMESTAMP + INTERVAL 5 DAY DO TRUNCATE TABLE test.aaa;
6) 每天定时清空test表,5天后停止执行:
CREATE EVENT e_test ON SCHEDULE EVERY 1 DAY ENDS CURRENT_TIMESTAMP + INTERVAL 5 DAY DO TRUNCATE TABLE test.aaa;
7) 5天后开启每天定时清空test表,一个月后停止执行:
CREATE EVENT e_test ON SCHEDULE EVERY 1 DAY STARTS CURRENT_TIMESTAMP +
INTERVAL 5 DAY ENDS CURRENT_TIMESTAMP + INTERVAL 1 MONTH DO TRUNCATE TABLE test.aaa;
[ON COMPLETION [NOT] PRESERVE]可以设置这个事件是执行一次还是持久执行,默认为NOT PRESERVE
8)
每天定时清空test表(只执行一次,任务完成后就终止该事件):
CREATE EVENT e_test ON SCHEDULE EVERY 1 DAY ON COMPLETION NOT PRESERVE DO TRUNCATE TABLE test.aaa;
[COMMENT
comment]可以给该事件加上注释
2>修改事件(ALTER EVENT)
ALTER EVENT event_name [ON SCHEDULE schedule] [RENAME TO new_event_name]
[ON COMPLETION [NOT] PRESERVE] [COMMENT 'comment'] [ENABLE | DISABLE] [DO
sql_statement]
1) 临时关闭事件
ALTER EVENT e_test DISABLE;
2) 开启事件
ALTER EVENT e_test ENABLE;
3) 将每天清空test表改为5天清空一次:
ALTER EVENT e_test ON SCHEDULE EVERY 5 DAY;
3>删除事件(DROP EVENT)
语法很简单,如下所示:
DROP EVENT [IF EXISTS] event_name
例如删除前面创建的e_test事件
DROP EVENT e_test;
当然前提是这个事件存在,否则会产生ERROR 1513 (HY000): Unknown event错误,因此最好加上IF EXISTS
DROP EVENT IF EXISTS e_test;
二、使用第三方工具来创建,推荐使用HeidiSQL网站:
http://www.heidisql.com/,免费的开源客户端,由德国程序员Ansgar Becker开发;这个软件的界面有中文界面。
打开HeidiSQL,右键单击表名,选创建新的的菜单,再选事件即可,很方便,我们可以编辑事件的时间设置和代码。这里定义人填写root@localhost。