[postgis-devel] Which intersection is faster?

Jorge Arévalo jorgearevalo at libregis.org
Sat Mar 23 10:50:50 PDT 2013


Many thanks for the quick response. I can see is pretty fast. But, what about previous version of PostGIS? Say 2.0. Is there any significant difference between both versions?   

--  
Jorge Arevalo
Freelance developer

http://www.krop.com/jorgearevalo
http://about.me/jorgeas80

Enviado con Sparrow (http://www.sparrowmailapp.com/?sig)


El sábado 23 de marzo de 2013 a las 18:30, Bborie Park escribió:

> I'd suggest using the variant that runs in raster space. If I
> remember correctly, some changes have been made to this in 2.1.
>  
> -bborie
>  
> On Sat, Mar 23, 2013 at 10:20 AM, Jorge Arévalo
> <jorgearevalo at libregis.org (mailto:jorgearevalo at libregis.org)> wrote:
> > Hello,
> >  
> > I don't know if this is a naive question, but in ST_Intersects description (http://postgis.net/docs/manual-2.0/RT_ST_Intersects.html) I read:
> >  
> > "Depending on the order that the raster and geometry is passed to ST_Intersects(), the test will operate in either raster-space or geometry-space. If ST_Intersects(raster, ....), the test is in raster-space (the geometry is converted to a raster). If ST_Intersects(geometry, ...), the test is in geometry-space (the raster is converted to a set of pixel polygons)."
> >  
> > My question: in equal conditions, which version should be faster?
> >  
> > ST_Intersects(raster, vector) --> in raster space
> > ST_Intersects(vector, raster) --> in vector space
> >  
> > Many thanks in advance,
> >  
> > --
> > Jorge Arevalo
> > Freelance developer
> >  
> > http://www.krop.com/jorgearevalo
> > http://about.me/jorgeas80
> >  
> > Enviado con Sparrow (http://www.sparrowmailapp.com/?sig)
> >  
> >  
> > _______________________________________________
> > postgis-devel mailing list
> > postgis-devel at lists.osgeo.org (mailto:postgis-devel at lists.osgeo.org)
> > http://lists.osgeo.org/cgi-bin/mailman/listinfo/postgis-devel
>  
>  
> _______________________________________________
> postgis-devel mailing list
> postgis-devel at lists.osgeo.org (mailto:postgis-devel at lists.osgeo.org)
> http://lists.osgeo.org/cgi-bin/mailman/listinfo/postgis-devel






More information about the postgis-devel mailing list