Extended value list from multiple tables
I am working on a database of articles which have different types of related documents, in this case they are separated in two tables for document and drawings. I've created the relationship between the article and the document/drawing through a linking lineitem register and I show these lineitems records in a portal in the article-layout. It is also through this portal I create the lineitem records.
As a validation, to only allow creation of lineitems on documents/drawings that already exist, I wanted to use 'Require member of value list'. I want to create this value list with the document IDs from the documents table AND the drawing IDs from the drawings table.
Is there any way I can create such an extended table? I've only encouterd filtering and conditional lists so far but not how to extend the list.
Greatful for all kind of response.
Best regards, Emelie