MYSQL存储过程及事件,MYSQL存储过程事件
关于mysql下的存储过程以及事件的创建
下面这个存储过程主要实现的功能就是查询表里面半年前的数据,如果有就存到文件,然后将数据删除。
CREATE DEFINER = `root`@`localhost` PROCEDURE `NewProc`() BEGIN select COUNT(*) INTO @count from S_ACCOUNT where date_add(registerTime, interval 6 month)<=NOW(); IF @count>0 THEN set @today=TIME_TO_SEC(now()); set @select_sql=concat("select * from S_ACCOUNT where date_add(registerTime, interval 6 month)<=NOW() INTO OUTFILE 'C:/\\",@today,".txt' FIELDS TERMINATED BY ',';"); PREPARE charu FROM @select_sql; EXECUTE charu; delete from S_ACCOUNT where date_add(registerTime, interval 6 month)<=NOW() ; commit; END IF; END;
FIELDS TERMINATED BY ',' 字段间分割符
OPTIONALLY ENCLOSED BY '"' 将字段包围 对数值型无效
LINES TERMINATED BY '\n' 换行符
下面是创建事件的代码 ,逻辑是从'2014-11-05 09:00:00'开始,每天去执行pro_test()这个过程。
CREATE DEFINER=`root`@`localhost` EVENT `NewEvent` ON SCHEDULE EVERY 1 DAY STARTS '2014-11-05 09:00:00' ON COMPLETION NOT PRESERVE ENABLE DO call pro_test();
当我们在创建事件的时候有可能会提示事件处于关闭状态,这个时候就需要手动开启事件。
首先在sql中查询计划事件的状态:SHOW VARIABLES LIKE 'event_scheduler'
如果返回的是off表示当前是关闭状态,如果是on当前已经开启了计划任务。
在mysql程序的目录下找到my.ini文件,添加一个项:event_scheduler = 1
保存后重启mysql服务即可,重启服务可以在服务管理里面找到.
也可以用脚本来实现:
mysql event_scheduler
开启event_scheduler sql指令:
SET GLOBAL event_scheduler = ON;
SET @@global.event_scheduler = ON;
SET GLOBAL event_scheduler = 1;
SET @@global.event_scheduler = 1;
相反,关闭event_scheduler指令:
SET GLOBAL event_scheduler = OFF;
SET @@global.event_scheduler = OFF;
SET GLOBAL event_scheduler = 0;
SET @@global.event_scheduler = 0;
查看event是否开启: show variables like '%sche%';
将事件计划开启: set global event_scheduler=1;
关闭事件任务: alter event e_test ON COMPLETION PRESERVE DISABLE;
开户事件任务: alter event e_test ON COMPLETION PRESERVE ENABLE;
简单实例.
创建表 CREATE TABLE test(endtime DATETIME);
创建存储过程test
CREATE PROCEDURE test ()
BEGIN
update examinfo SET endtime = now() WHERE id = 14;
END;
创建event e_test
CREATE EVENT if not exists e_test
on schedule every 30 second
on completion preserve
do call test();
每隔30秒将执行存储过程test,将当前时间更新到examinfo表中id=14的记录的endtime字段中去.
应该不能在存储过程过程调用事件, "forbidden"就是很好的提示!