Re: [SQL] LIMIT 1 FOR UPDATE or FOR UPDATE LIMIT 1?

Tom Lane wrote:
> Bruce Momjian <pgman(at)candle(dot)pha(dot)pa(dot)us> writes:
> > Larry Rosenman wrote:
> >> Why? If both old and new are acceptable, why not document it?
> >> (Just curious, I'm not wedded to it).
>
> > Well, showing both versions adds confusion for no good reason,
>
> Yes, particularly considering that LIMIT ... FOR UPDATE corresponds
> to the implementation behavior (LIMIT acts before FOR UPDATE) while
> FOR UPDATE ... LIMIT does not.
>
> I concur with documenting only the preferred form (though there should
> be a note in gram.y explaining that we're supporting the old syntax
> for backward compatibility).

I originally thought the grammar would be ugly to support both, but in
fact it has almost the same number of actions as before, so we can keep
it around for a while if not forever.

I will update the gram.y comments to indicate it will live beyond 7.3.X.

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