protected function getMatchingIds($objFilter)
    {
        if ($objFilter) {
            $arrFilteredIds = $objFilter->getMatchingIds();
            if ($arrFilteredIds !== null) {
                return $arrFilteredIds;
            }
        }

        // Either no filter object or all ids allowed => return all ids.
        // if no id filter is passed, we assume all ids are provided.
        return $this->getConnection()->createQueryBuilder()
            ->select('id')
            ->from($this->getTableName())
            ->execute()
            ->fetchAll(\PDO::FETCH_COLUMN);
    }