Marko Tiikkaja <marko@joh.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.
regards, tom lane