[postgis-devel] Another Data Point

[Paul Ramsey]

Using the original sample set from Lee Keel,

With the old style ST_Union, 3 hours, 27 minutes:

uniontest=# select st_area(st_union(the_geom)) from sample_poly;
      st_area
--------------------
 0.0324039850011104
(1 row)

Time: 12419261.819 ms


With the new cascaded ST_Union, 4 minutes, 30 seconds, or 46 times faster.

uniontest=# select st_area(st_union_fast(the_geom)) from sample_poly;
      st_area
--------------------
 0.0324039850054305
(1 row)

Time: 271618.181 ms


That's one nasty data set.

P.