[postgis-users] Simplifying a multipolygon layer, keeping polygon connection

[Sandro Santilli]

On Wed, Apr 11, 2012 at 11:14:48AM +0200, Nicolas Ribot wrote:

> Yes, here are some stats:
> 
> Mac OS X Snow Leopard, SSD drive, 8 gb ram
> shared_buffers = 5120MB
> work_mem = 1024MB
> 
> POSTGIS="2.0.0 r9605" GEOS="3.3.2-CAPI-1.7.2" PROJ="Rel. 4.7.1, 23
> September 2009" GDAL="GDAL 1.8.0, released 2011/01/12" LIBXML="2.7.8"
> TOPOLOGY RASTER
> 
> Number of objects in departement layer: 96 Num points  47036,
> 
> 1°) Using spatial functions:
> First run: 8953.493 ms, second run: 8808.133 ms
> 
> 2°) Using Topology
> First run: 13743 ms, second run: 14028 ms
> 
> (server stopped and restarted between runs.

Which steps involved by the two methods ?

I can see some steps are in common:
 1: Loading of input 
 2: Linking of faces to attribute (area_orig/area_intersection) 

Could the first step be taken out and the second be
profiled separately ?

--strk;

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