Re: Add red-black tree missing comparison searches

Steve Chavez <steve@supabase.io>

From: Steve Chavez <steve@supabase.io>
To: Alexander Korotkov <aekorotkov@gmail.com>
Cc: pgsql-hackers <pgsql-hackers@postgresql.org>
Date: 2022-07-02T19:38:41Z
Lists: pgsql-hackers

Attachments

Hey Alexander,

> But I think we can support strict inequalities too (e.g.
less and greater without equals).  Could you please make it a bool
argument equal_matches?

Sure, an argument is a good idea to keep the code shorter.

> Could you please extract this change as a separate patch.

Done!

On Thu, 30 Jun 2022 at 14:34, Alexander Korotkov <aekorotkov@gmail.com>
wrote:

> Hi, Steve!
>
> Thank you for working on this.
>
> On Thu, Jun 30, 2022 at 7:51 PM Steve Chavez <steve@supabase.io> wrote:
> > Currently the red-black tree implementation only has an equality search.
> Other extensions might need other comparison searches, like less-or-equal
> or greater-or-equal. For example OrioleDB defines a greater-or-equal search
> on its postgres fork:
> >
> >
> https://github.com/orioledb/postgres/blob/4c18ae94c20e3e95c374b9947f1ace7d1d6497a1/src/backend/lib/rbtree.c#L164-L186
> >
> > So I thought this might be valuable to have in core. I've added
> less-or-equal and greater-or-equal searches functions plus tests in the
> test_rbtree module. I can add the remaining less/great searches if this is
> deemed worth it.
>
> Looks good.  But I think we can support strict inequalities too (e.g.
> less and greater without equals).  Could you please make it a bool
> argument equal_matches?
>
> > Also I refactored the sentinel used in the rbtree.c to use C99
> designators.
>
> Could you please extract this change as a separate patch.
>
> ------
> Regards,
> Alexander Korotkov
>

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →
  1. Add missing inequality searches to rbtree

  2. Use C99 designator in the rbtree sentinel definition