[postgis-users] Does anyone have multipolygons with large numbersof polygons

[Kevin Neufeld]

You called it.

Obe, Regina wrote:
> ...
>
> Looking at Kevin's results I am beginning to think the bottleneck may be
> in the GeomN type functions and maybe he is right that its doing a copy
> call for each or something silly like that or a memory leak (I wasn't
> looking is it linear or quadratic as the number of geometries
> increases?).
>
>
> Kevin,
> What happens if you leave out the PointN call altogether just to see
> what kind of penalty is being incurred there.
> e.g.
> SELECT t.gid, generate_series(1, ST_NumPoints(the_geom))
> FROM kneufeld.tmp t
>
>   
                                                 QUERY 
PLAN                                                
------------------------------------------------------------------------------------------------------------
 Seq Scan on tmp t  (cost=0.00..1.01 rows=1 width=339661) (actual 
time=134.755..213.814 rows=21227 loops=1)
 Total runtime: 280.351 ms
 Total runtime: 148.297 ms
 Total runtime: 147.929 ms
 Total runtime: 147.780 ms