> Databases for business tend to have a longer life span than
> many other technologies. It is one of the reasons that the
> technology tends to trail behind other technological advances.
> There is a large inertia behind significant database systems.

I do not agree with you here. There are old systems developed in last
century, and there are new systems that have modern needs, not the
workarounds for old issues.

I agree with Sean that users and applications do not need this
feature, or more correctly need a concept of a "group" (which Jim
seems to not like). But when we talk about users and applications we
have forgotten about the application servers.

Personally I see the value of the possibility to switch
roles/users/groups (name it whatever you like) when the security
context from the application server is promoted to the database. It
seems to be technically possible and I think would increase the
overall data security/safety.

Roman