[postgis-users] Difference between ST_Union and ST_Collect

[Sandro Santilli]

On Fri, May 25, 2012 at 01:52:45PM +1000, Luca Morandini wrote:

> after seeing some polygons disappear during the generalization
> process, I found out that ST_Union and ST_Collect are different
> beasts when dealing with intersecting lines.

Yes, ST_Collect simply puts things togheter. ST_Union computes the
point set union. Isn't the manual page clear about that ?

> P.S.
> Sandro, I did not forget to help speeding up the topology
> construction routines, it is just that next week we have a deadline,
> hence I gave a lower priority to the task of setting up a machine
> with the configuration you requested... stay tuned.

I am ! 

--strk; 

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