[postgis-users] postgis topology performance

[Sandro Santilli]

On Tue, Mar 25, 2014 at 03:13:13PM +0100, Rémi Cura wrote:
> Back after some other testing .
> 
> (_from memory, suppressing checks in addpoints was about 2 sec instead of 3
> sec.
> _About 21k unique points.)
> 
> 
> Here is a little comparison :
> (32k polylines,21k unique points,  already 'topological'( no need to cut
> the lines) ,with a lot of attributes)
> 
> Postgis Topology
> Postgis Topology (addtopogeom) : 700+ sec for 10k lines, (??about 1600 sec
> for 32k lines??)
> Postgis Topology (addlinestring) : 240+ sec for 10k lines,  (??about 780
> sec for 32k lines??)
> Postgis Topology (addnode, addedge) : 80sec for 10 k lines (??about 260sec
> for 32k lines??)
> 
> Grass Gis 7 :
> Importing everything : 10 sec
> Importing only geom (no attributes) : 5 sec
> 
> Importing everything then Exporting all topologies to postgis topology :
> 150 sec
> Declare postgis topo as external source and fill it with shapefile : 145 sec

Nice! GRASS seems to be the way to go here.
It's interesting to see how a 10-seconds process becomes a 150-seconds
one to ensure output is modeled after PostGIS/ISO model. There's maybe
space for optimization there.

--strk;

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