Re: Allow an alias for the target table in UPDATE/DELETE

From: Martijn van Oosterhout <kleptog(at)svana(dot)org>
To: Andrew Dunstan <andrew(at)dunslane(dot)net>
Cc: pgsql-patches(at)postgresql(dot)org
Subject: Re: Allow an alias for the target table in UPDATE/DELETE
Date: 2006-01-22 15:06:30
Message-ID: 20060122150630.GC18590@svana.org
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On Sun, Jan 22, 2006 at 09:04:14AM -0500, Andrew Dunstan wrote:
> >If you don't like relying on file order to resolve this, appropriate
> >use of %prec would have the same effect (just like for operator
> >precedence). The output file tell you which way bison went.

> If we allow shift/reduce or reduce/reduce conflicts, debugging future
> development becomes more difficult. Right now we have the nice property
> that if you see one of those you know you've done something wrong (and
> using the expect directive isn't really a good answer, and only applies
> to shift/reduce conflicts anyway).

But that's the point of the %prec directive. To force bison to choose
one or the other, thus removing the warning... For an ambiguity that
only appears in one statement, it seems a better solution than upgrade
SET to a new class of identifier.

Have a nice day,
--
Martijn van Oosterhout <kleptog(at)svana(dot)org> http://svana.org/kleptog/
> Patent. n. Genius is 5% inspiration and 95% perspiration. A patent is a
> tool for doing 5% of the work and then sitting around waiting for someone
> else to do the other 95% so you can sue them.

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