如果要每30秒执行以下语句：

update userinfo set endtime = now() WHERE id = '110';

可以给mysql建个定时任务，具体方法如下：

delimiter //   /* 设定语句终结符为 //，因存储过程语句用;结束 */

一、查看event是否开启

show variables like '%sche%';

开启event_scheduler

set global event_scheduler =1;

二、创建存储过程test

CREATE PROCEDURE test ()
BEGIN
update userinfo set endtime = now() where id = '110';
END;

三、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

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;