Synchronized combo boxes in a table NOT A FORM?

[vercon]

I have a table which includes two columns 'Catergory' and 'Application'. In the category field I'm using a lookup, but I want the 'Application' field to be populated according to what's been selected in the 'Category' field. Can somone explain how to do this?

[SteveH2508]

1. You cannot do this in a table.

2. You have a normalisation problem with your data. If a field in a table depends on another field in that table which is not the primary key field, you have what is called a transitive dependency. You should have a separate table related to the original with Category as the Primary Key and Application as another field. Category then becomes a foreign key in your original table.

3. I would avoid using look-ups in tables as well - they cause all sorts of problems.

[vercon]

whats the best way to approach this then? basically I want a form which will display the details of a particular machine, then below a table showing what applications are running on that machine?

[SteveH2508]

This is a classic main-form/sub-form set up. Machine on the main form and the Applications table sources the sub-form (1 to many relationship between Machine and Application tables). The wizard can set it up.