[postgis-users] Considerations on performance: union on 59000geometries

[pcreso at pcreso.com]

One approach I have used with over 1m geometries is to script up an iterative loop combining 1000 geometries, then adding the next 1000, etc...
until all have been included. 

I generally use bash under Linux, but this can be done more efficiently in Perl or python.

HTH,

  Brent Wood



--- On Tue, 7/21/09, Juan Pedro Pérez Alcántara <jp.alcantara at geo-st.com> wrote:

> From: Juan Pedro Pérez Alcántara <jp.alcantara at geo-st.com>
> Subject: Re: [postgis-users] Considerations on performance: union on 59000geometries
> To: "PostGIS Users Discussion" <postgis-users at postgis.refractions.net>
> Date: Tuesday, July 21, 2009, 7:08 PM
> Thank you. I'll try.
> 
> Regards,
> 
> Juan Pedro Pérez Alcántara
> 
> On Mon, 2009-07-20 at 14:40 -0400, Paragon Corporation
> wrote:
> > Which version  of PostGIS are you using. 
> The upcoming 1.4 is much much
> > faster and may do the trick for you.  Its in rc2
> now.  Ready to release any
> > day.
> > 
> > There is no way the 1.3 will complete with 59,000 in
> one go.
> > 
> > Leo
> > 
> > -----Original Message-----
> > From: postgis-users-bounces at postgis.refractions.net
> > [mailto:postgis-users-bounces at postgis.refractions.net]
> On Behalf Of Juan
> > Pedro Pérez Alcántara
> > Sent: Monday, July 20, 2009 2:10 PM
> > To: postgis-users at postgis.refractions.net
> > Subject: [postgis-users] Considerations on
> performance: union on
> > 59000geometries
> > 
> > Hello everybody,
> > 
> > today I tried to perform a union on 59000 geometries,
> but the operation
> > seems not to complete. In no way I'm an expert in
> PostgreSQL/PostGIS
> > optimization, and for sure my system is not in the
> perfect shape to address
> > such operations with elegance.
> > 
> > My questions are:
> > 
> > * should PostGIS be able to perform this operation if
> properly optimized?
> > and
> > 
> > * could you please advise me some piece of
> documentation for learning about
> > PostgreSQL / PostGIS optimization?
> > 
> > I read somewhere that the french cartographic service
> has migrated to
> > PostGIS, so I have no doubt that this have to be
> possible to achieve, and
> > speaks loud about the importance of optimization
> issues.
> > 
> > Regards,
> > 
> > Juan Pedro Pérez Alcántara
> > 
> > 
> > _______________________________________________
> > postgis-users mailing list
> > postgis-users at postgis.refractions.net
> > http://postgis.refractions.net/mailman/listinfo/postgis-users
> > 
> > 
> > _______________________________________________
> > postgis-users mailing list
> > postgis-users at postgis.refractions.net
> > http://postgis.refractions.net/mailman/listinfo/postgis-users
> > 
> 
> 
> _______________________________________________
> postgis-users mailing list
> postgis-users at postgis.refractions.net
> http://postgis.refractions.net/mailman/listinfo/postgis-users
>