在次问竹子，关于论坛im项目的一个问题，困扰了我一天了

首先很感谢竹子那么快给我提供im项目的sql脚本文件，今天项目在机器上部署好了，然后主要是登录之后进入index.jsp页面后Hibernate无限向数据库发送sql，具体代码如下：

Hibernate: select user0_.Id as Id1_, user0_.username as username1_, user0_.password as password1_ from t_user user0_ where user0_.username=?
Hibernate: select user0_.Id as Id1_, user0_.username as username1_, user0_.password as password1_ from t_user user0_ where user0_.username=?
Hibernate: select count(*) as col_0_0_ from t_message message0_ where message0_.userIdTo=? and (message0_.datetimeRead is null)
Hibernate: select message0_.Id as Id0_, message0_.userIdFrom as userIdFrom0_, message0_.userIdTo as userIdTo0_, message0_.message as message0_, message0_.datetimeCreate as datetime5_0_, message0_.datetimeRead as datetime6_0_ from t_message message0_ where message0_.userIdTo=? and (message0_.datetimeRead is null)
Hibernate: select user0_.Id as Id1_, user0_.username as username1_, user0_.password as password1_ from t_user user0_ where user0_.username=?
Hibernate: select count(*) as col_0_0_ from t_message message0_ where message0_.userIdTo=? and (message0_.datetimeRead is null)

前4句我可以理解，但是后面两句只要index.jsp没有关闭，就好像死循环一下，在控制台无限的刷，折磨了我一天了，我在想是不是因为Ajax的问题，无限像服务器发送请求，但是我对Ajax还不了解啊，请竹子帮忙看下这个现象的问题出在哪？

没错，Ajax每隔一段时间就去查询是否有最新的数据。