[OSM-dev] projection for calculating distances in PostGIS

[John Smith]

On 19 May 2010 22:06, Marcus Wolschon <Marcus at wolschon.biz> wrote:
> Hello,
>
> what projections do you use to calculate distances (in meters) in postgis?
> I have some code here that tried to use 27700 but that is not defined
> on all inhabited continents of this planet.
> An error of at most 25% would be acceptable as tis is just about search
> -areas and not street-length.

If you generate an area that you want to cover, then all you need to
do is use ST_Within() function I think it is.