public static function getWarningsForUserByType($userId, $type)
 {
     $userId = Database::makeStringSafe($userId);
     $type = Database::makeStringSafe($type);
     $result = Database::doQuery("SELECT * FROM " . Database::addPrefix(WarningDao::table_name) . " WHERE user_id = '" . $userId . "' and type = '" . $type . "'");
     $warnings = array();
     while ($row = mysql_fetch_assoc($result)) {
         $warnings[] = WarningDao::buildWarning($row);
     }
     return $warnings;
 }