Long story short, I have a custom field on purchase order line level (line reference), and I would like to pass this information on on the purchase order. The user should be able to filter purchase orders based on the purchase order line references etc.

As the purchase order and purchase order line models are already linked, I thought I would be able to simply create a related field on purchase order model that would include all the purchase order line references of this particular purchase order. So I created a related field on the developer mode on the purchase order as follows:

- model: purchase order

- field type: char

- related field: order_line.linereference (in which linereference is my custom field on purchase order line model)

However, based on some testing it seems that the result of this approach is that the related field on the purchase order level contains only the line reference of the first purchase order line. I'm sure that as a beginner I have misunderstood something, and any help would be greatly appreciated!