Record ID pk / fk fields -- can I create them after the fact?
I'm working on a database that's been in use for a couple of years (I did not create it) and has over 10k records. Many of the tables link to multiple fields in the central hub. I think it would be better served if the central hub used an ID pk, and the other tables linked to this with an ID fk.
Can I add these pk / fk fields after the fact?
If so, what is the safest way to do so?