recursive views

I had some time during vacation to thing about postgresql. And here's the
feature I'd really like to see. This one would put us miles in front of all
others: recursive view definitions.

Just one short example:

There is that well-known parent relation: par (parent, child). The view anc
now should list all ancestors:

create view anc as
    select parent as ancestor, child as person from par
    union
    select anc.ancestor as ancestor, par.child as person
    from anc, par
    where anc.person = par.parent;

What do you guys think of this idea? How much work would it be to implement
it?

Michael
--
Dr. Michael Meskes, Project-Manager    | topsystem Systemhaus GmbH
meskes@topsystem.de                    | Europark A2, Adenauerstr. 20
meskes@debian.org                      | 52146 Wuerselen
Go SF49ers! Go Rhein Fire!             | Tel: (+49) 2405/4670-44
Use Debian GNU/Linux!                  | Fax: (+49) 2405/4670-10