That's deeply odd, and worth investigating. Can you try 8.3+1.3.3, so we can eliminate the PostGIS version as a variable first? Then I'll see if I can duplicate the result on my system.
P. On Sat, Sep 27, 2008 at 12:59 PM, David Vaz <[EMAIL PROTECTED]> wrote: > Hi, > > I am a debian user, several months ago debian testing introduced > postgresql-8.3, and later postgis 1.3 for postgresql-8.3. The problem I > am facing is that length_spheroid is much slower in postgres-8.3 from > under 1s to about 60s (See Bellow). I have google-it without any luck. > Does anyone have any idea on why this happens? > > Both databases are equal, tested in same machine, with different > installations to avoid software versions conflicts. > > FIRST: > postgresql-8.2 (version 8.2.7-2+b1) with postgis (version 1.3.2-1) > > EXPLAIN ANALYSE select length_spheroid(geom,'SPHEROID["WGS > 84",6378137,298.257223563]') FROM test order by id limit 100; > > QUERY > PLAN > ------------------------------------------------------------------------------------------------------------------------------------------------------- > Limit (cost=0.00..17.44 rows=100 width=26054) (actual > time=1.852..588.394 rows=100 loops=1) > -> Index Scan using test_pkey on test (cost=0.00..2268.52 > rows=13010 width=26054) (actual time=1.850..588.298 rows=100 loops=1) > Total runtime: 588.495 ms > (3 rows) > > SECOND: > postgresql-8.3 (version 8.3.3-1) with postgis (version 1.3.3-3) > > EXPLAIN ANALYSE select length_spheroid(geom,'SPHEROID["WGS > 84",6378137,298.257223563]') FROM test order by id limit 100; > > QUERY > PLAN > > ------------------------------------------------------------------------------------------------------------------------------------------------------------ > Limit (cost=0.00..8.74 rows=100 width=104429) (actual > time=182.734..59741.720 rows=100 loops=1) > -> Index Scan using test_pkey on test (cost=0.00..1137.11 > rows=13010 width=104429) (actual time=182.732..59741.572 rows=100 loops=1) > Total runtime: 59741.897 ms > (3 rows) > > _______________________________________________ > 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
