Fred's got it, listen to Fred!!! (Never build a buffer if you don't need to.)
On Mon, Jun 29, 2009 at 9:16 AM, Fred Lehodey<[email protected]> wrote: > Hi Marco, > ST_DWithin(geometry, geometry, float) > > Returns true if geometries are within the specified distance of one another. > Uses indexes if available. > > HTH, > Fred > > > > > On Mon, Jun 29, 2009 at 4:46 PM, Marco Lechner - FOSSGIS e.V. > <[email protected]> wrote: >> >> hi list, >> >> we are using within(geometry, geometry) to test if some (~1200) points >> are within a polygon. the polygon is defined as buffer(linegeometry, >> dist). the problem is, that the line is always the same and therefore >> the result of buffer(linegeometry, dist) is always the same. while >> iterating through the points the within() calculates the >> buffer(linegeometry) each time again. the function takes 40s. instead of >> 0.04s if i calculate the buffergeometry first and use it as "fixed >> geometry" at within() - is this somehow improvable (within() recognizing >> such a behaviour?, ...)? >> >> Marco >> _______________________________________________ >> postgis-users mailing list >> [email protected] >> http://postgis.refractions.net/mailman/listinfo/postgis-users > > > _______________________________________________ > postgis-users mailing list > [email protected] > http://postgis.refractions.net/mailman/listinfo/postgis-users > > _______________________________________________ postgis-users mailing list [email protected] http://postgis.refractions.net/mailman/listinfo/postgis-users
