On Sat, Oct 17, 2009 at 9:41 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> I've been thinking about this since your earlier mail, and I think it
> would probably be possible to suppress unused columns in a non-flattened
> subquery. I remain unconvinced that it's worth the trouble though.
> A real (not handwavy) example would help make the case here.
Are there any situations where this would enable join removal that
otherwise wouldn't be possible? Maybe a query involving an
unflattenable VIEW?
...Robert