Session is stored in mysql database _ MySQL

The session is stored in the mysql database according to the session class in qq interconnection and the official php example.

 lifetime = get_cfg_var("session.gc_maxlifetime");  $this->dbHandle = $con;  if(!$con || !$sel)      return false;      return true; }function close(){    $this->gc($this->lifetime);return @mysql_close($this->dbHandle);}function read($id){   $rs = @mysql_query("select session_data data from ".self::db_table." where session_expires < ".time(),$this->dbHandle);    $row = @mysql_fetch_assoc($rs);return $row?$row['data']:'';}function write($id,$data){$newEXP = time()+ ini_get("session.gc_maxlifetime");   $sel = mysql_query("select * from ".self::db_table." where session_id= '".$id."'",$this->dbHandle);   if(mysql_affected_rows($this->dbHandle)){     $rs = @mysql_query("update ".self::db_table." set session_data = '".$data."', session_expires = '".$newEXP."' WHERE session_id = '".$id."'",$this->dbHandle);  if(@mysql_affected_rows($this->dbHandle))  return true;   }else{     $rs = @mysql_query("insert into ".self::db_table." (session_id,session_data,session_expires)values('".$id."','".$data."','".$newEXP."')",$this->dbHandle); if(@mysql_affected_rows($rs)) return true;   }   return false;}function destroy($id){@mysql_query("delete from ".self::db_table." where session_id = '".$id."'",$this->dbHandle);}function gc($lifetime){    @mysql_query("delete from ".self::db_table." where sessoin_expires > '".time()."'",$this->dbHandle);}}$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();