[postgis-users] Why PostGIS ST_Intersection much slower than ArcGIS Intersect ?

[Paul Ramsey]

Google knows,
http://trac.osgeo.org/geos/wiki/PreparedGeometry
http://blog.cleverelephant.ca/2008/10/postgis-performance-prepared-geometry.html

p

On Fri, Nov 30, 2012 at 11:11 PM, Andrea Peri <aperi2007 at gmail.com> wrote:
> Hi Paul,
>
> I like understand better this situation.
>
> I read often that to fast the ST_Intersect() over huge geometry is
> better to clip them on lower size geometries.
> This is understandable for me.
>
> But the Etienne use-case speak of the ST_Intersection() don't the
> ST_Intersect (that is fast instead).
>
> My doubt is "Why is fast the ST_Intersects() if it is a huge geometry ?"
>
> And when you say a "prepared intersection" are speaking of the usual
> teorical solution to clip a huge geometry on a set of lower sized
> geometries ?
>
> Thx,
>
> --
> -----------------
> Andrea Peri
> . . . . . . . . .
> qwerty àèìòù
> -----------------
> _______________________________________________
> postgis-users mailing list
> postgis-users at lists.osgeo.org
> http://lists.osgeo.org/cgi-bin/mailman/listinfo/postgis-users