On Tuesday 22 April 2008, Paul Ramsey wrote: > The operators (@, &&, etc) all work on bounding boxes. The functions > all work on full geometries. It is possible for geometries to satisfy > bounding box containment while not satisfying full geometric > containment, hence your discrepancy. > > P.
Thanks for the clarification. Does it make sense any more to use one of the &&, @, etc. operators to pre-filter geometries, or do the ST_ functions take care of that in call cases? i.e. can you think of any cases where it would still be a good idea to use something like select st_intersection(a,b) from a, b on a && b ; Thanks, Dylan > On Tue, Apr 22, 2008 at 8:36 AM, Frank Durstewitz > > <[EMAIL PROTECTED]> wrote: > > Hi, > > can someone please explain, what the difference between > > > > WHERE ST_CONTAINS(b.geom, e.geom) > > > > and > > > > WHERE e.geom @ b.geom > > > > is? (b.geom are (multi-)polygons and e.geom are points) > > > > I expect to get the same results, but with @ i get a few more > > records...? > > > > TIA, Frank > > > > > > > > _______________________________________________ > > postgis-users mailing list > > postgis-users@postgis.refractions.net > > http://postgis.refractions.net/mailman/listinfo/postgis-users > > _______________________________________________ > postgis-users mailing list > postgis-users@postgis.refractions.net > http://postgis.refractions.net/mailman/listinfo/postgis-users -- Dylan Beaudette Soil Resource Laboratory http://casoilresource.lawr.ucdavis.edu/ University of California at Davis 530.754.7341 _______________________________________________ postgis-users mailing list postgis-users@postgis.refractions.net http://postgis.refractions.net/mailman/listinfo/postgis-users