"Why are you asking MySQL questions in a SQL Server Newsgroup? "

I actually am using MySQL and posted in the wrong group by accident.
However, I'm less worried about the specific features mysql or
postgres or mssql has that would deal with my problem as much as
general way of dealing with this as I'm thinking of switching to
postgres once mysql is close-sourced by sun.

As for the solutions, the cascade looks pretty interesting and I'll
try that if I have time in the next few days. Also, I looked up some
of the terms given in Hugo's response, found lots of good stuff like:

http://troels.arvin.dk/db/rdbms/links/#hierarchical

thanks!