Re: Per-column collation, work in progress

On tor, 2010-10-14 at 22:54 -0400, Robert Haas wrote:
> It seems you've falsified the header comment in
> pathkeys_useful_for_merging(), although I guess it's already false
> because it doesn't seem to have been updated for the NULLS ASC/DESC
> stuff, and the interior comment in right_merge_direction() also needs
> adjusting.  But this might be more than a documentation problem,
> because the choice of merge direction really *is* arbitrary in the
> case of ASC/DESC and NULLS FIRST/LAST, but I'm not sure whether that's
> actually true for collation.  If collation affects the definition of
> equality then it certainly isn't true.

I did check that again and didn't arrive at the conclusion that the
comments would need updating either with respect to this patch or some
previous change.  Could you check again and possibly provide a
suggestion?