Re: SKIP LOCKED DATA (work in progress)

On Sat, May 17, 2014 at 1:02 AM, Craig Ringer <craig(at)2ndquadrant(dot)com> wrote:

> We have a long tradition of trying to allow noise keywords where it's
> harmless.
>
> So the clause should probably be
>
> SKIP LOCKED [DATA]
>
> in much the same way we have
>
> BEGIN [ WORK | TRANSACTION ] ...
>
> There won't be any ambiguity there.

We've had some problems in the past where allowing optional noise
words resulted in grammar conflicts that made future features harder
to add. See previous discussions about LOCK TABLE, wherein we almost
went to the extreme of adding a completely separate ACQUIRE LOCK
command. A lot of these things seem harmless when you first do them,
and then later they seem less harmless.

Anyway, +1 for the general idea of this feature. It's come up a
number of times on this mailing list, and we've had customer requests
for it, too.

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company