Re: [BUGFIX] amcanbackward is not checked before building backward index paths

On Wed, May 16, 2018 at 4:54 PM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:

> Alexander Korotkov <a(dot)korotkov(at)postgrespro(dot)ru> writes:
> > On Wed, May 16, 2018 at 1:41 AM, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
> >> Perhaps there is a case for adding an additional flag to allow
> specifying
> >> "I can't support ORDER BY DESC", but I'm not in a big hurry to do so.
> >> I think there would be more changes than this needed to handle such a
> >> restriction, anyway.
>
> > OK, got it. We'll probably propose a patch implementing that to the
> > next commitfest.
>
> If you do, it wouldn't be a bad idea to try to clarify the existing
> code and docs around this point. I'm thinking that amcanbackward is
> misleadingly named; maybe we should rename it as part of the change?
>

I was thinking about naming new property as amcanorderbydesc,
which is kind of non-overlapping with amcanbackward. For sure,
amcanbackward could be renamed, but I don't have ideas of better
name for now.

------
Alexander Korotkov
Postgres Professional: http://www.postgrespro.com
The Russian Postgres Company