A simple problem with value lists?

[Sharon]

Hi, 

I'm trying something that seems very simple, but I can't make it work for some reason. I've tried all sorts of joining tables etc.

I have three tables: A, B, and C. Table A is the parent of both B and C. (so there is no actual relation between B and C, but there are records in B and C with a common A father).

I want to add a field to C that will store a field's value from B.  For that, I want to create a value list of values from B for the user to choose from. However, I do not want to show every possible value from B, only those that share a common father in A with the relevant record of C. 

Is there a simple solution for that?

Thank you

[comment]

Define your value list to use values from field B:Somefield, include only related values starting from A.

--
P.S. Please use meaningful names for your tables and fields when asking; abstract examples are very difficult to follow.

 

[Sharon]

Thank you for your reply. I will use meaningful names in the future, sorry. 

My first thought was exactly what you describe (this is why I thought it was simple),  but it didn't work. 

I've tried it again and realized my situation is more complicated. While it works perfectly in a simple layout of C (I'll stick to these names for now), I'm using a script that opens a new window as a card for creating a new record in C, and the user should choose the value from the list there. I don't understand why it works in the simple layout but not the card. Any idea?

[comment]

6 minutes ago, Sharon said:

Any idea?

Not really. If the layout of the card window is a layout of C, then it should make no difference. Perhaps you're using a different occurrence of the C table - one that is not related to A and through that to B?

Of course, if it's a new record then the user must first select a parent from A before they can choose from the values in B that are related to the selected parent.

 

[Sharon]

Ok. I realize my mistake now. I've used the value list not for a simple field but for adding records in a portal that shows lines of a joining table. I understand now that the context of the portal is not the context of the layout it appear in, but rather the context of the joining table. I solved it with another instance of a table and it seems to work fine. Thank you very much for your time and answers