Re: ST_Distance Issue

On Thu, Nov 17, 2011 at 4:29 AM, Archana Sachin Ghag <
Archana_Ghag(at)infosys(dot)com> wrote:

> I am calculating distance from my current location with all available
> regions(polygons) in my table.****
>
> I am using ST_Distance method for this.****
>
> My regions are stored with SRID = 900913.****
>
> ** **
>
> Distance for point in Europe from USA region is coming as 122.78.****
>
> How come this possible. These regions are so far.****
>
> ** **
>
> Here is my query. Can you please suggest me how can I get actual distance
> in meters here.****
>
> ** **
>
> SELECT distance****
>
> (st_geomfromtext('point(-123.574219125 47.8131546948944 0)', 900913),****
>
> st_geomfromtext('LINESTRING(-0.791015625 48.4874864798841,9.4921875
> 54.5975278521139,27.59765625 55.3541353102106,36.38671875
> 48.3124279040718,22.32421875 40.3465441211801,5.888671875
> 43.8662180065564,-0.791015625 48.4874864798841)', 900913)****
>
> )****
>
> ** **
>
> Query returns 122.785055218779****
>
> ** **
>
> What is significance of SRID here. Am I missing something?****
>
> Which SRID should we use for general purpose.
>

This mailing list is for bugs in PostgreSQL; it sounds like you have a user
question about PostGIS.

I think this might be the right place:

http://postgis.refractions.net/mailman/listinfo/postgis-users

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