mysql 如何实现字段值数字改变时服务器推送？
数据库是下图所示：
如何能实现当num里的值增加或减少的时候，可以进行服务器推送？
我现在在显示页用的定时器加普通ajax查询的，虽然这样可以达到效果，可以当数据库数据没有变化时还在不停的发送请求。
我想实现当某一个num值改变时，前台显示页才会发送请求。
该如何实现？
回复内容：
数据库是下图所示：
如何能实现当num里的值增加或减少的时候，可以进行服务器推送？
我现在在显示页用的定时器加普通ajax查询的，虽然这样可以达到效果，可以当数据库数据没有变化时还在不停的发送请求。
我想实现当某一个num值改变时，前台显示页才会发送请求。
该如何实现？
这个东西不能在MySQL层面实现. 你业务层要修改数据的时候, 需要主动通知给观察者. 可以去搜搜消息中间件之类的东西.
1.Ajax长轮询
2.socket
我认为你说的意思是希望前台的展示页面当后台数据变化的同时进行刷新。
我建议你看看 meteor，meteor官网
segmenfault的说明
中文说明文档
学习meteor我目前知道的中文最好的地方
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