Iblock::getElementIds

private function getElementIds(int $iblockId, int $limit, int $offset): array
{
	$elementIds = [];

	$connection = Application::getInstance()->getConnection();
	$sqlHelper = $connection->getSqlHelper();

	$queryObject = $connection->query("SELECT ID FROM `b_iblock_element` WHERE `IBLOCK_ID` = '".
		$sqlHelper->forSql($iblockId)."' ORDER BY ID ASC LIMIT ".$limit." OFFSET ".$offset);
	$selectedRowsCount = $queryObject->getSelectedRowsCount();
	while ($element = $queryObject->fetch())
	{
		$elementIds[] = $element["ID"];
	}

	return [$elementIds, $selectedRowsCount];
}