How to set a reference type property for an infoblock element via the Bitrix API?

Question

1C-Bitrix

Could you please tell me how to set a lookup type property when creating an element, so as to associate a product (infoblock element) with a specific entry in the block's highload list?

There is a catalog of goods, it is necessary to create new goods in the code, having received data from a CSV file. Goods have a Material property - PR_MATERIAL of the reference type stored in the highload block Material

. This is how the PR_MATERIAL property is displayed in the settings of the goods catalog infoblock



. How to do it?



Which field of the highload element of the block should be used to link: ID, external code (UF_XML_ID)?

This is how the highload fields of the Material block look like, the external code is UF_XML_ID

The highload table of the Material block is called b_hlbd_material