Re: nearest neighbor search from xyz coordinates
| От | Serge Fonville |
|---|---|
| Тема | Re: nearest neighbor search from xyz coordinates |
| Дата | |
| Msg-id | 680cbe0e0810270426t567cfc2bia38e0d570f6b91f3@mail.gmail.com обсуждение исходный текст |
| Ответ на | nearest neighbor search from xyz coordinates (Andreas Jochem <andruit@gmx.de>) |
| Список | pgsql-general |
What exactly do you want to measure, since values can be compared easily by a where clause
If you would want for example all rows within a spherical distance
you will either have to write a stored procedure (which takes 4 parameters x,y,z,distance)
Or manually compare each corodinate to the distance
Regards,
Serge Fonville
On Mon, Oct 27, 2008 at 11:50 AM, Andreas Jochem <andruit@gmx.de> wrote:
Hello,
I have a table containing x y z coordinates. But I have no geometry column?
Is it possible to find the k nearest neighbors of any point. Is there something like a kd-tree Index in postgres???
I know, if i had a geometry column I could make use of the distance function to find the k nearest neighbors. But my table has millions of records, thus it would take a very long time to use the distance function for each point.
Thanks in advance.
Andi
--
Sent via pgsql-general mailing list (pgsql-general@postgresql.org)
To make changes to your subscription:
http://www.postgresql.org/mailpref/pgsql-general
В списке pgsql-general по дате отправления: