protected static function isValidRawSearch(array $rawSearch) {
        if (false === array_key_exists(DataTablesSearchInterface::DATATABLES_PARAMETER_REGEX, $rawSearch)) {
            return false;
        }
        if (false === array_key_exists(DataTablesSearchInterface::DATATABLES_PARAMETER_VALUE, $rawSearch)) {
            return false;
        }
        return true;
    }