[postgis-users] ST_Dump-like function for simple (non-multi) geometries ?

[Maxime van Noppen]

On 08/05/09 14:47, Maxime van Noppen wrote:
> Thanks. However Robe (cf ticket) and you are right, there is a
> scalability issue. For the sake of the test I've implemented the ST_Dump
> function in plpgsql with a recursive call (as my_ST_DumpPoints is) and
> in some very bad cases it's very slow. For example I've tested to dump a
> geometry containing 100 nested GEOMETRYCOLLECTION containing each 10
> multipolygons. ST_Dump runs in 35ms whereas my_ST_Dump runs in 230ms
> (sorry if I'm stating obvious things here, I'm quite new to the postgis
> world).
> 
> On the same example (100 nested collections) my_ST_DumpPoints runs in
> ~2 seconds which is quite alot. I'll try to come up with a C version,
> but it seems quite more complicated.

Hm, the test case is the other way : 10 nested geometry collections of
100 multipolygons each.

-- 
yabo