Peter Eisentraut <peter_e@gmx.net> writes:
> ... Therefore I ask whether everyone agrees
> that groups and roles are basically equivalent concepts (and perhaps that
> we might in the future strive to make groups more compatible with the
> roles as defined in the SQL standard). Or does anyone see that roles
> might be implemented separately from groups sometime?
Just reading section 4.31.3 of the SQL99 draft, it seems that roles are
pretty much interchangeable with groups, except that a role can be a
member of another role while we don't presently allow groups to be
members of other groups.
So it seems that your question breaks down to:
1. Do we want to someday allow groups to have groups as members? (Seems
reasonable to me.)
2. Are there any other differences between groups and roles? (I'm not
sure about this one.)
regards, tom lane