CUG

Hi,

what would be the best way to implement a closed user group in an app
with postgresql ?

The app will be a cgi, so there will be an enormous number of
'guest'-users.

Groups should be containable in other groups (AFAIK this is not possible
in
postgresql's group management).

Up to now I had my own user/group management (one col per table
indicating the
group which has read-access).
It was easy to check permissions in my app and in WHERE clauses.
But now I need groups of groups which needs some kind of recursion.
Therefore I would write a (recursive) plpgsql function which I can use
in my app
and in arbitrary sql-queries' WHERE clauses.

Q: Before I do this, I would like to know whether this is the correct
approach.
Q: Should I use the built in user/group features ? (If not: What are
they there for?)
Q: Are there other mechanisms to handle tree-structures ? With properly
defined
   REFERENCES this should be possible (?) The only hints on recursions
and postgresql
   where features to AVOID recursion :((((((

TIA

-- 
 Nabil Sayegh
 GPG-Key available at http://www.sayegh.de 
 (see http://www.gnupg.org for details)