Can a table be automatically filled since it has only Foreign Keys?

1

Hello!
So I have the following 4 Tables in here: SQL Fiddle with 4 Tables

I would like my 4th Table, Certificates to be automatically filled/updated since it doesn’t have anything unique.
It just haves 3 Foreign Keys.

I want to be able to use that a reference for linking my Tables with JOINs.

Thanks a lot!