Re: query help on Geography column

On Wed, Feb 17, 2016 at 3:28 AM, Tony Sansom <antonys(at)nsom(dot)org(dot)uk> wrote:

> HI I’m struggling with retuning data from the following query. It should
> be retuning all data within a 5k radius of a given Longitude, Latitude
> point.
>
> Select stuff from MyGeoTable where
> ST_DWithin(ST_GeographyFromText(‘SRID=4326;POINT(LONG,LAT)’), geog,5000)
>
> Is not retuning all data it should be best guess there is an issue with
> the Geography column this was created from a geometry column which is a
> collection of points lines and polygons
>
> I tried to recreate the Geography thus
>
> Update MyGeoTable set geog = ­(ST_Transform(geom,4326));
>
> This gives “ERROR: Geometry type (LINSTRING) dose not match column type
> (Polygon)”
>
> My question is twofold
>
> 1st how can recreate the geography column, check it has worked?
>
> 2nd How might perform a similar query just using the geometry the 5k
> radius doesn’t have to be exact!
> ​
>
>
​This seems like a poor choice of forum for these questions. Of the
official PostgreSQL mailing lists -general would be better. But as these
types and functions are not part of the core PostgreSQL product these are a
bit off-topic for any of these lists. I presume you are using PostGIS and
so you should locate a list dedicate to discussing their product.

​-admin is mostly about DBA-related stuff like running and configuring a
PostgreSQL instance. Schema stuff could qualify (first question) but
usually usage questions (2nd question) end up in either -general or -sql if
they are agnostic enough.​

David J.