> > ERROR: triggered data change violation on relation "groups"
>
> Yes. For some technical reason ( I'm not clear on this ) you cannot
> both add and delete the same row within a PostgreSQL transaction. This
> is a known issue in 7.1.x; I do not know if it is fixed in 7.2.
Hmmm...I seem to recall that it is fixed in 7.2. Correct me if I'm wrong.
Chris