ItemService::getItemIdsBySourceIds

public function getItemIdsBySourceIds(array $sourceIds, array $entityIds = []): array
{
	$itemIds = [];

	$filter = ['SOURCE_ID' => $sourceIds];
	if ($entityIds)
	{
		$filter['ENTITY_ID'] = $entityIds;
	}

	$queryParams = [
		'select' => ['ID'],
		'filter' => $filter,
		'order' => [
			'SORT' => 'ASC',
			'ID' => 'DESC',
		],
	];

	$queryObject = ItemTable::getList($queryParams);

	while ($itemData = $queryObject->fetch())
	{
		$itemIds[] = $itemData['ID'];
	}

	return $itemIds;
}