private function entryExists($hash)
    {
        $queryBuilder = $this->connection->createQueryBuilder();
        $queryBuilder->from($this->table, 'backlog');
        $queryBuilder->andWhere('backlog.hash = :hash');
        $queryBuilder->setParameter(':hash', $hash);
        $queryBuilder->setMaxResults(1);
        $queryBuilder->select('backlog.id');

        $backlog = $queryBuilder->execute()->fetch(PDO::FETCH_ASSOC);

        if (!empty($backlog)) {
            return true;
        }

        return false;
    }
private function entryExists($hash)
    {
        $queryBuilder = $this->connection->createQueryBuilder();
        $queryBuilder->from($this->table, 'backlog');
        $queryBuilder->andWhere('backlog.hash = :hash');
        $queryBuilder->setParameter(':hash', $hash);
        $queryBuilder->setMaxResults(1);
        $queryBuilder->select('backlog.id');

        $backlog = $queryBuilder->execute()->fetch(PDO::FETCH_ASSOC);

        if (!empty($backlog)) {
            return true;
        }

        return false;
    }
@param string $hash

@return bool