Re: Feature: FOR UPDATE SKIP LOCKED

On Wed, 2008-07-09 at 00:48 -0400, Tom Lane wrote:
> "Jonathan Bond-Caron" <jbondc@gmail.com> writes:
> > It would be quite useful to implement a database queue. Although FOR UPDATE
> > NOWAIT and trying again can work as well as other techniques,
>
> > just skipping over the locks has its advantages (simplicity and zero wait)
>
> And disadvantages, such as complete lack of predictability or failure
> detection.

Well, it's not like SQL is completely predictable in general... think
about ordering of results. Such a feature would definitely help queue
like table processing, and the fact that it is predictably unpredictable
should not be a surprise for anybody using such a feature...

Cheers,
Csaba.