Displaying values of a deeper nested list virtual column in a column of a shallower list


I have a table of invoices (named “Invoices”), where every invoice has a list of line items. These items are being taken from from another list named “Invoices Line Item” and presented in a virtual column with the following expression:

REF_ROWS("Invoices Line Item", "_ID")

Every line item has a virtual column ProductGroups with the following expression to produce values:

FILTER("ProductGroupsByModels", IN([Modell], [_THISROW].[DescrParts]))

This results in a list of textual values for every line item of every invoice. The goal is to somehow aggregate the lists of ProductGroups over all line items into a single list and present it in a column of the Invoices table.

An example:

An invoice has 2 line items. First line item implies product groups g1 and g2 and the second one gives g3. I need to present a list consisting of g1, g2 and g3 in the according row of Invoices.

How can this be done?

Thank you in advance.

Hi @rreimche

Welcome to the community !
You may want to use a list dereference.

Assuming this:
REF_ROWS("Invoices Line Item", "_ID")
is a column named “Related LineItems”

You may want to use this expression in a new virtual column of your Invoices Table:
[Related LineItems][ProductGroups]

To do so:

For reference: