public function findLastIndexedRow(int $rootPageId) : array
    {
        $queryBuilder = $this->getQueryBuilder();
        $row = $queryBuilder
            ->select('uid', 'indexed')
            ->from($this->table)
            ->where($queryBuilder->expr()->eq('root', $rootPageId))
            ->andWhere($queryBuilder->expr()->neq('indexed', 0))
            ->orderBy('indexed', 'DESC')
            ->setMaxResults(1)
            ->execute()->fetchAll();

        return $row;
    }