public function loadCollectionReferencesData(Block $block, ?string $identifier = null): array
    {
        $query = $this->connection->createQueryBuilder();
        $query->select('block_id', 'block_status', 'collection_id', 'collection_status', 'identifier')
            ->from('ngbm_block_collection')
            ->where(
                $query->expr()->eq('block_id', ':block_id')
            )
            ->setParameter('block_id', $block->id, Type::INTEGER)
            ->orderBy('identifier', 'ASC');

        $this->applyStatusCondition($query, $block->status, 'block_status');

        if ($identifier !== null) {
            $query->andWhere($query->expr()->eq('identifier', ':identifier'))
                ->setParameter('identifier', $identifier, Type::STRING);
        }

        return $query->execute()->fetchAll(PDO::FETCH_ASSOC);
    }