This is a matter between you and the database. :-)

You haven't said what brand of database engine you're accessing, and it WILL
make a difference. In Access and others, you usually define foreign keys in
the records and the database takes care of the rest. In Sybase, you need to
define them separately and then update them independently (I think), but you
can do this using triggers.

No matter what, though, it's something you need to do on the database side,
not the Excel VBA side.