Filter lookup list with specific values

fabrizioc

Hi to all, I'm newer with Navision and in these days I'm facing a lot of new "small issues" (of course due to my lack of experience with Navision).
I need to limit possible values in a lookup list, I've seen this is possible using TableRelation property with a filter but, till now I've always seen example with 2 table involved.....In my scenario I have 3 table involved, from the first table I can retrieve the key of a second table and, using this key on a third table I can filter possible values.

Just an example to explain:

In my Table Tests I have 2 fields contract ID and Transport ID both are lookup fileds, Id' like to populate Transport ID with only values allowed a specific locations, the locations can be discovered looking at contracts table. So to summarize I start with the Contract ID, I find in the location tables all the location with a specific contracts id, now I want the lookup of Transport ID to open only with those locations, can someone suggest me a way to do this.

Thank you in advance for your precious help.

Fabrizio