Re: SELECT FOR UPDATE NOWAIT

Paulo Scardine wrote:
> (Excuse my english, my native language is portuguese)
>
> > I think I'm a quite attentive to the SQL and HACKERS list, and I see
> > requests for a NOWAIT option at least once a month, and it's growing.
> > Regards, Christoph
>
> Yes. I have done a little google about "pgsql select for update nowait" and
> find lot of people looking for this feature.
>
> If there is a lock and NOWAIT is specified, then raise error instead of
> waiting for the lock to release. We have some long distance connections that
> get very busy sometimes and is hard to distinguish between network problems
> and locked rows.
>
> Do you see it as something hard to implement? Any advice?
> Is it just to add an "opt_nowait" to the "FOR UPDATE" clause in the parser
> and checking for this option when trying to get the lock later?

My guess is that we will implement it was a SET variable so it can
control FOR UPDATE/LOCK/UPDATE/DELETE.

Added to TODO:

Add GUC variable to prevent waiting on locks

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