php session存数据库

这个sesison存到数据库很简单，就是根据session_id进行对数据库的CRUD操作，主要是用到了，session_set_save_handler这个方法，自定义session的执行方法，

首先创建数据表

 CREATE TABLE `sessions` (
  `session_id` varchar(255) NOT NULL,
  `session_expires` int(11) DEFAULT NULL,
  `session_data` text,
  PRIMARY KEY (`session_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8
然后封装操作session的工具类：
<?php
//error_reporting(0);
class session {

   var $lifeTime;

   var $dbHandle;
   function open($savePath, $sessName) {

       $this->lifeTime = get_cfg_var("session.gc_maxlifetime");

       $dbHandle = mysql_connect("localhost","root","root");
       $dbSel = mysql_select_db("mysession",$dbHandle);

       if(!$dbHandle || !$dbSel)
           return false;
       $this->dbHandle = $dbHandle;
       return true;
   }
   function close() {
       $this->gc(ini_get('session.gc_maxlifetime'));

       return @mysql_close($this->dbHandle);
   }
   function read($sessID) {

       $res = mysql_query("SELECT session_data AS d FROM sessions
                           WHERE session_id = '$sessID'
                           AND session_expires > ".time(),$this->dbHandle);

       if($row = mysql_fetch_assoc($res))
           return $row['d'];
       return "";
   }
   function write($sessID,$sessData) {

       $newExp = time() + $this->lifeTime;

       $res = mysql_query("SELECT * FROM sessions
                           WHERE session_id = '$sessID'",$this->dbHandle);

       if($res) {

           mysql_query("UPDATE sessions SET session_expires = '{$newExp}',session_data = '{$sessData}' WHERE session_id = '{$sessID}'",$this->dbHandle);

           if(mysql_affected_rows($this->dbHandle))
               return true;
       }

       else {

           mysql_query("INSERT INTO sessions (
                         session_id,
                         session_expires,
                         session_data)
                         VALUES(
                         '{$sessID}',
						 '{$newExp}',
						 '{$sessData}')",$this->dbHandle);

           if(mysql_affected_rows($this->dbHandle))
               return true;
       }

       return false;
   }
   function destroy($sessID) {

       mysql_query("DELETE FROM sessions WHERE session_id = '$sessID'",$this->dbHandle);

       if(mysql_affected_rows($this->dbHandle))
           return true;

       return false;
   }
   function gc($sessMaxLifeTime) {

       mysql_query("DELETE FROM sessions WHERE session_expires < ".time(),$this->dbHandle);

       return mysql_affected_rows($this->dbHandle);
   }
}
#对session进行测试，发现数据库中并没有存入数据只有session_id,和session_expires的数值,其实session_data是存在的只是我们看不到
 $session = new session();
	session_set_save_handler(array(&$session,"open"),
							 array(&$session,"close"),
							 array(&$session,"read"),
							 array(&$session,"write"),
							 array(&$session,"destroy"),
							 array(&$session,"gc"));
			session_start();
			$session->write(session_id(),json_encode(array("name"=>"gxx","pass"=>"123")));
			echo $session->read(session_id());
?>
这里居然不支持插图。。

数据库数据:
s430j9t480ocbovq6a7a0rlk22    1435054078
session查询数据:
JSON

name"gxx"
pass"123"

不要被事物蒙蔽了眼睛。。。。