[fw-db] Saving a Zend_Db_Table_Row with relationships

Lets say we have a users table, a groups table and an intersection table
called usergroups. I my application I have a Users class to represent
the users table (extends Zend_Db_Table) and a User class to represent
one user (extends Zend_Db_Table_Row). The same goes for the other tables
as well.

Now ... lets say we have a form where we want to edit a user (including
adding/removing groups). How would you guys go about implementing the
saving of the user object and the group relationships?

I'm thinking of writing a custom save() method in the User class that
first calls parent::save() to save the user to the users table, and then
implement stuff for saving data to the usergroups intersection table. I
would also need to add some attributes to the User class and make sure
the group relationshis is loaded when a User object is created. Is this
the "regular" way of solving this or does Zend_Db have some kind of
magic stuff to handle this?

How do other people solve this?

--
Christer Edvartsen
cogo@starzinger.net
http://cogo.wordpress.com/