ClientDataProvider::splitFieldsToSelect

protected function splitFieldsToSelect(): array
{
	$selectFields = [];
	$selectMultifields = [];

	$multifieldTypes = array_merge(
		\CCrmFieldMulti::GetEntityTypeList(),
		\CCrmFieldMulti::GetEntityComplexList()
	);

	foreach ($this->realSelectFields as $fieldId)
	{
		if (isset($multifieldTypes[$fieldId]))
		{
			$selectMultifields[] = $fieldId;
		}
		else // not a multifield
		{
			$selectFields[] = $fieldId;
		}
	}

	return [
		'fields' => $selectFields,
		'multifields' => $selectMultifields,
	];
}