public function editQuota(SiteModel $site, UserAccountModel $user = null)
 {
     global $DB;
     $stat = $DB->prepare("UPDATE site_information SET site_quota_id=:site_quota_id WHERE id=:id");
     $stat->execute(array('site_quota_id' => $site->getSiteQuotaId(), 'id' => $site->getId()));
 }