On Wed, Mar 30, 2011 at 10:58:57AM +0100, Ioannis Anagnostopoulos wrote: > I am involved in a heavy database design initiative where the only kind > of geometries I am dealing with are points. I have recently hit a > 50million rows long table with those points and my default gist index on > the points does not seem to be working very fast (if not at all to be > honest). I have started now thinking that probably for "points" an index > may not be the best option since in a 50million rows long table most of > the points are unique so the index may just duplicate the actual table, > of course I may be wrong and I may just missing a very important part of > the concept.
How many points from the 50M set does your tipical query hits ? Does PostgreSQL selectivity estimator make a good guess about that ? Use EXPLAIN ANALYZE <your query here> to see. --strk; () Free GIS & Flash consultant/developer /\ http://strk.keybit.net/services.html _______________________________________________ postgis-users mailing list [email protected] http://postgis.refractions.net/mailman/listinfo/postgis-users
