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mysql event的用法

Jun 07, 2016 pm 03:09 PM
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欢迎进入Linux社区论坛,与200万技术人员互动交流 >>进入 MySQL从5.1开始支持event功能,类似oracle的job功能。有了这个功能之后我们就可以让MySQL自动的执行数据汇总等功能,不用像以前需要操作系统提供的定时器的支持了。如linux crontab功能。 创建测试表

欢迎进入Linux社区论坛,与200万技术人员互动交流 >>进入

  MySQL从5.1开始支持event功能,类似oracle的job功能。有了这个功能之后我们就可以让MySQL自动的执行数据汇总等功能,不用像以前需要操作系统提供的定时器的支持了。如linux crontab功能。

  创建测试表

  CREATE TABLE t

  (

  v VARCHAR(100) NOT NULL

  ) ENGINE INNODB DEFAULT CHARSET=utf8;

  创建定时器调用的存储过程

  DELIMITER $$

  DROP PROCEDURE IF EXISTS e_test $$

  CREATE PROCEDURE e_test()

  BEGIN

  INSERT INTO t VALUES('1');

  END $$

  DELIMITER ;

  要使定时起作用 MySQL的常量GLOBAL event_scheduler必须为on或者是1

  -- 查看是否开启定时器

  SHOW VARIABLES LIKE '%sche%';

  -- 开启定时器 0:off 1:on

  SET GLOBAL event_scheduler = 1;

  -- 创建事件

  --每隔一秒自动调用e_test()存储过程

  CREATE EVENT IF NOT EXISTS event_test

  ON SCHEDULE EVERY 1 SECOND

  ON COMPLETION PRESERVE

  DO CALL e_test();

  -- 开启事件

  ALTER EVENT event_test ON

  COMPLETION PRESERVE ENABLE;

  -- 关闭事件

  ALTER EVENT event_test ON

  COMPLETION PRESERVE DISABLE;

  SELECT * FROM t;

  一些例子:

  从现在开始每隔九天定时执行

  CREATE EVENT EVENT1

  ON SCHEDULE EVERY 9 DAY STARTS NOW()

  ON COMPLETION PRESERVE ENABLE

  DO

  BEGIN

  CALL TOTAL();

  END

  每个月的一号凌晨1 点执行

  CREATE EVENT EVENT2

  ON SCHEDULE EVERY 1 MONTH STARTS DATE_ADD(DATE_ADD(DATE_SUB(CURDATE(),INTERVAL DAY(CURDATE())-1 DAY), INTERVAL 1 MONTH),INTERVAL 1 HOUR)

  ON COMPLETION PRESERVE ENABLE

  DO

  BEGIN

  CALL STAT();

  END

  每个季度一号的凌晨2点执行

  CREATE EVENT TOTAL_SEASON_EVENT

  ON SCHEDULE EVERY 1 QUARTER STARTS DATE_ADD(DATE_ADD(DATE( CONCAT(YEAR(CURDATE()),'-',ELT(QUARTER(CURDATE()),1,4,7,10),'-',1)),INTERVAL 1 QUARTER),INTERVAL 2 HOUR)

  ON COMPLETION PRESERVE ENABLE

  DO

  BEGIN

  CALL SEASON_STAT();

  END

  每年1月1号凌晨四点执行

  CREATE EVENT TOTAL_YEAR_EVENT

  ON SCHEDULE EVERY 1 YEAR STARTS DATE_ADD(DATE(CONCAT(YEAR(CURDATE()) + 1,'-',1,'-',1)),INTERVAL 4 HOUR)

  ON COMPLETION PRESERVE ENABLE

  DO

  BEGIN

  CALL YEAR_STAT();

  END

mysql event的用法

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