Re: point types in "DISTINCT" queries

On Wed, Jun 29, 2011 at 06:53, Jeff Davis <pgsql(at)j-davis(dot)com> wrote:
> On Tue, 2011-06-28 at 18:56 -0400, Jonathan S. Katz wrote:
>
>> I looked into the mailing list archives and found a potential answer
>> on this thread:
>> http://archives.postgresql.org/pgsql-general/2009-10/msg01122.php
>> However I wanted to see if it was still necessary that I would need
>> the complete btree operator class to run such a query.
>
> Yes, the default btree operator class is used to find the equality
> operator. Even though you have defined the operator "=", postgresql
> doesn't rely on that meaning "equals" -- the btree operator class is
> what imparts that meaning.
>
>> Are there plans to have a defined "=" operator on the point type?  I
>> can understand how the other geometric types, "=" would represent
>> area, but AFAIK I think "=" could be safely applied on a point type
>> (and i realize I could submit a patch for that :-) maybe depending on
>> the resolution to this / refreshing my C...).
>
> The built-in geometric types haven't received a lot of attention lately.
> Most people who use geometric data use the PostGIS extension, which is a
> sophisticated extension that can deal with that kind of data. You might
> want to check that out and see if it meets your needs.
>
> Perhaps someone is interested in bringing the built-in geometric types
> up to speed; but I think most of the interest is moving things like this
> out to extensions where they can be more easily be maintained by
> interested parties.

Given that they are the only ones supporting knn-gist, I would expect
them to actually become *more* popular with 9.1 - at least until such
time as postgis adds support for it...

--
 Magnus Hagander
 Me: http://www.hagander.net/
 Work: http://www.redpill-linpro.com/