Left list: Problems with linking tables

SOLVED

Hi,

I have a problem with a left list. I want to add a field in a left list which consists of the BPADDRESS fields POSCOD and CITY. ([F:BPA]POSCOD-[F:BPA]CTY). Only the default address should be shown.

In order to only shown the default address I added a selection option:

I tried two things to add the mentioned field in the left list.

Attempt one:

In the environment section I added the BPADDRESS table to my object with the corresponding join expression:

In the selection section I added the expression to show the field:

Problem: The field was shown with this attempt, but no data is shown.

When I run a sql query with the same Join Condition I get records.

I found an object with a left list which has also linked multiple tables and which uses as a field combined of two DB attributes. There it works. I found no difference with my attempt.

Attempt two:

I added the mentioned field with a return value of a function:

The function looks like this:

Problem: Data (POSCOD - CTY) is returned, but the left list is not filterable with this attribute.

Can everybody help me? What do I wrong?

Thank you very much for your help.

Kind regards