Re: GSOC13 proposal - extend RETURNING syntax

On 2013-05-02 12:23:19 -0400, Tom Lane wrote:
> Marko Tiikkaja <marko(at)joh(dot)to> writes:
> > What I'm more interested in is: how can we make this feature work in
> > PL/PgSQL where OLD means something different?
>
> That's a really good point: if you follow this approach then you're
> creating fundamental conflicts for use of the feature in trigger
> functions or rules, which will necessarily have conflicting uses of
> those names. Yeah, we could define scoping rules such that there's
> an unambiguous interpretation, but then the user is just out of luck
> if he wants to reference the other definition. (This problem is
> probably actually worse if you implement with reserved words rather
> than aliases.)
>
> I'm thinking it would be better to invent some other notation for access
> to old-row values.

prior/after? Both are unreserved keywords atm and it seems far less
likely to have conflicts than new/old.

Greetings,

Andres Freund

--
Andres Freund http://www.2ndQuadrant.com/
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