[postgis-users] postgis performance

[Markus Schaber]

Hi, Fratzis,

 - fratzis at olympiacos.net wrote:

> query="select gid,nomos,code_nomos,AsText(the_geom) from nomoi";
> rs = s.executeQuery( query );

Why do you use AsText(the_geom) here?

Try to use the PostGIS jdbc extension, so you can get the MultiPolygon
via rs.getObject(4), this uses the faster EWKB representation internally.

> MultiPolygon mpol = new MultiPolygon( rs.getString(4) );

This would look like:

PGgeometry wrapper = (PGgeometry) rs.getObject(4);
MultiPolygon mpol = (MultiPolygon) wrapper.getGeometry();

According to my bogus benchmarks, this provides a speedup up to factor
20 on server and client side.

> Polygon tmp = new Polygon(  );
> tmp = mpol.getPolygon(0);
Why are you initializing tmp with a new, empty polygon that is just food
for the garbage collector here?

HTH,
Markus