Re: SELECT FOR UPDATE NOWAIT

Tom Lane wrote:
> "Paulo Scardine" <paulos(at)cimed(dot)ind(dot)br> writes:
> > - Where is the best place to put this?
>
> I think it would be a really *bad* idea to put it in LockAcquire; that
> risks breaking things that you don't want broken.
>
> Whether it's special syntax or a GUC variable, the restriction should
> only apply to SELECT FOR UPDATE row locks, perhaps user-commanded LOCK
> TABLE operations, and maybe one or two other places that are known to
> be used only for user-written operations and not for system-initiated
> ones. Those places would need to check whether to do a conditional
> or unconditional lock.

My original idea was to have it apply only for exclusive locks. It
seemed those were mostly the locks didn't want to wait for. Shared
locking pg_class is something that you would want to wait for.

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