session 入库

    <?php  
    ini_set("session.save_handler","user");  
    //session.gc_probability = 1 分子  
    ini_set("session.gc_probability",1);  
    //session.gc_divisor = 1000 分母  
    ini_set("session.gc_divisor",2);  
    //session.gc_maxlifetime = 1440 垃圾回收时间，session有效期  
    $maxlifetime = ini_set("session.gc_maxlifetime");  
      
    session_set_save_handler( "open","close","read","write","destroy","gc" );  
      
    //连接数据库  
    function open(){  
        @$link = mysql_connect('127.0.0.1', 'root', 'root');  
        mysql_query('set names utf8');  
        mysql_query('use xxx');  
    }  
    function close(){  
        mysql_close();  
    }  
    function read($sess_id){  
        $sql = "select session_data from `session` where session_id = '$sess_id'";  
        $result = mysql_query($sql);  
        if($rows = mysql_fetch_assoc($result)){  
      
            return $rows['session_data']; }else{  
            return '';  
      
        }  
    }  
    function write($sess_id,$sess_data){  
        $sql = "insert into `session` (session_id,session_data,session_time) values('$sess_id','$sess_data', now())  
    on duplicate key update session_data = '$sess_data' , session_time = now()  
    ";  //这是为了gc()  
        return mysql_query($sql);  
      
    }  
    function destroy($sess_id){  
        echo __FUNCTION__;  
        $sql = "delete from `session` where session_id = '$sess_id'";  
        return mysql_query($sql);  
      
    }  
    function gc($sess_id){  
        echo __FUNCTION__;  
        $sql = "delete from `session` where now()-session_time > '$maxlifetime' ";  
        return mysql_query($sql);  
    }  
    header("content-type:text/html;charset=utf8");  
    session_start();  
    $_SESSION['name']='zhangsan';  
    //echo session_id();  
    echo $_SESSION['name'];  
      
    ?>