Re: [PATCH v2] Introduce spgist quadtree @<(point,circle) operator

Hi Matwey,

On Tue, May 21, 2019 at 10:23 AM Matwey V. Kornilov
<matwey.kornilov@gmail.com> wrote:
> вт, 21 мая 2019 г. в 08:43, Michael Paquier <michael@paquier.xyz>:
> >
> > On Mon, May 20, 2019 at 02:32:39PM +0300, Matwey V. Kornilov wrote:
> > > This patch series is to add support for spgist quadtree @<(point,circle)
> > > operator. The first two patches are to refactor existing code before
> > > implemention the new feature. The third commit is the actual implementation
> > > provided with a set of simple unit tests.
> >
> > Could you add that to the next commit fest please?  Here you go:
> > https://commitfest.postgresql.org/23/
>
> Done

Thank you for posting this patch.  A took a look at it.

It appears that you make quadrant-based checks.  But it seems to be
lossy in comparison with box-based checks.  Let me explain this on the
example.  Imagine centroids (0,1) and (1,0).  Square (0,0)-(1,1) is
intersection of quadrant 2 of (0,1) and quadrant 4 of (1,0).  And then
imagine circle with center in (2,2) of radius 1.  It intersects with
both quadrants, but doesn't intersect with square.

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