https://blog.youkuaiyun.com/strive_bozh-cnhttps://blog.youkuaiyun.com/https://blog.youkuaiyun.com/strive_bo/article/details/8830495https://blog.youkuaiyun.com/strive_bo/article/details/8830495strive_boSun, 21 Apr 2013 11:44:35 +0800https://blog.youkuaiyun.com/strive_bo/article/details/7854671https://blog.youkuaiyun.com/strive_bo/article/details/7854671strive_boSat, 11 Aug 2012 14:44:49 +0800https://blog.youkuaiyun.com/strive_bo/article/details/7819586https://blog.youkuaiyun.com/strive_bo/article/details/7819586strive_boWed, 01 Aug 2012 17:54:34 +0800https://blog.youkuaiyun.com/strive_bo/article/details/7776374https://blog.youkuaiyun.com/strive_bo/article/details/7776374strive_boMon, 23 Jul 2012 17:40:18 +0800 Brower Filters，会打开B]]>https://blog.youkuaiyun.com/strive_bo/article/details/7760040https://blog.youkuaiyun.com/strive_bo/article/details/7760040strive_boWed, 18 Jul 2012 17:06:43 +0800https://blog.youkuaiyun.com/strive_bo/article/details/7528194https://blog.youkuaiyun.com/strive_bo/article/details/7528194strive_boWed, 02 May 2012 15:33:07 +0800https://blog.youkuaiyun.com/strive_bo/article/details/7344640https://blog.youkuaiyun.com/strive_bo/article/details/7344640strive_boMon, 12 Mar 2012 13:58:13 +0800https://blog.youkuaiyun.com/strive_bo/article/details/7077761https://blog.youkuaiyun.com/strive_bo/article/details/7077761strive_boFri, 16 Dec 2011 15:58:11 +0800https://blog.youkuaiyun.com/strive_bo/article/details/7034749https://blog.youkuaiyun.com/strive_bo/article/details/7034749strive_boFri, 02 Dec 2011 13:42:57 +0800https://blog.youkuaiyun.com/strive_bo/article/details/6914930https://blog.youkuaiyun.com/strive_bo/article/details/6914930strive_boFri, 28 Oct 2011 16:20:05 +0800https://blog.youkuaiyun.com/strive_bo/article/details/6883359https://blog.youkuaiyun.com/strive_bo/article/details/6883359strive_boTue, 18 Oct 2011 09:36:21 +0800https://blog.youkuaiyun.com/strive_bo/article/details/6854854https://blog.youkuaiyun.com/strive_bo/article/details/6854854strive_boSun, 09 Oct 2011 11:00:13 +0800https://blog.youkuaiyun.com/strive_bo/article/details/6761003https://blog.youkuaiyun.com/strive_bo/article/details/6761003strive_boThu, 08 Sep 2011 17:09:28 +0800https://blog.youkuaiyun.com/strive_bo/article/details/6742879https://blog.youkuaiyun.com/strive_bo/article/details/6742879strive_boFri, 02 Sep 2011 14:19:21 +0800https://blog.youkuaiyun.com/strive_bo/article/details/6679463https://blog.youkuaiyun.com/strive_bo/article/details/6679463strive_boThu, 11 Aug 2011 16:41:15 +0800https://blog.youkuaiyun.com/strive_bo/article/details/6669322https://blog.youkuaiyun.com/strive_bo/article/details/6669322strive_boMon, 08 Aug 2011 14:56:04 +0800https://blog.youkuaiyun.com/strive_bo/article/details/6078009https://blog.youkuaiyun.com/strive_bo/article/details/6078009strive_boWed, 15 Dec 2010 16:38:00 +0800https://blog.youkuaiyun.com/strive_bo/article/details/5951176https://blog.youkuaiyun.com/strive_bo/article/details/5951176strive_boTue, 19 Oct 2010 14:09:00 +0800网络层---数据包的包格式里面有个很重要的字段叫做协议号。比如在传输层如果是TCP连接，那么在网络层IP包里面的协议号就将会有个值是6，如果是UDP的话那个值就是17---传输层。传输层---通过接口关联(端口的字段叫做端口)---应用层。用netstat –an 可以查看本机开放的端口号。代理服务器常用以下端口：（1）. HTTP协议代理服务器常用端口号：80/8080/3128/8081/9080（2）. SOCKS代理协议服务器常用端口号：1080（3）. FTP（文件传输）协议代理服务器]]>https://blog.youkuaiyun.com/strive_bo/article/details/5909269https://blog.youkuaiyun.com/strive_bo/article/details/5909269strive_boMon, 27 Sep 2010 11:37:00 +0800什么是长连接？
其实长连接是相对于通常的短连接而说的，也就是长时间保持客户端与服务端的连接状态。
通常的短连接操作步骤是：
连接-》数据传输-》关闭连接；
而长连接通常就是：
连接-》数据传输-》保持连接-》数据传输-》保持连接-》…………-》关闭连接；
这就要求长连接在没有数据通信时，定时发送数据包，以维持连接状态，短连接在没有数据传输时直接关闭就行了
什么时候用长连接，短连接？
长连接主要用于在少数客户端与服务端]]>https://blog.youkuaiyun.com/strive_bo/article/details/5886618https://blog.youkuaiyun.com/strive_bo/article/details/5886618strive_boWed, 15 Sep 2010 18:00:00 +0800 
 
 
    一些常见的sql函数
 

    select to_char(sysdate,'yyyy') from dual;  --计算出当前日期的年份
   
    select to_char(sysdate,'mm') from dual;    --计算出当前日期的月份
   
    select to_char(sysdate,'dd') from dual;   ]]>