> In a nutshell, then, I'd like my users to be able to alter the data
> in the tables, but only the data that they can see in the views, and
> only in a way so it remains in their views after modification.
> Has anyone got any advice?
I've seen Veil suggested for problems like yours. It is a PostgreSQL addon.
http://pgfoundry.org/projects/veil/
Regards,
Richard Broersma Jr.