protected function getLimit(array $queryParts)
    {
        if (isset($queryParts['limit']) && !empty($queryParts['limit'])) {
            $limit = [];
            foreach ($queryParts['limit'] as $int) {
                $limit[] = (int)$int;
            }

            return 'LIMIT ' . implode(', ', $limit);
        }

        return null;
    }