public static function do_zone($zone, $dbb = NULL)
 {
     $db = NULL;
     if (!empty($dbb)) {
         $db = $dbb;
     } else {
         $db = new Class_DB();
     }
     $sql = sprintf(" SELECT * FROM M_ZONE WHERE zone_name =  '%s' ", $zone);
     $db->query($sql);
     if ($row = $db->fetch()) {
         return $row["zone_cd"];
     } else {
         $loginuser = $_SESSION['ADMIN_LOGIN']['STAFF_SEQ'];
         $sql = sprintf(" INSERT INTO  M_zone(zone_name, c_time, c_user) values('%s', CURRENT_TIMESTAMP, '%s') ", $zone, $loginuser);
         $db->query($sql);
         return $db->last_id();
     }
 }