[postgis-users] topology performance improvement purpose

[Ben Madin]

Do you need to even change the search_path - surely you could have a function version with the 'topology' schema hard-coded for the performance improvement. Obviously that won't work if you have a different schema name, but if the performance enhancement is worth it, grepping out topology to whatever you need will also be worth the effort.

cheers

Ben


On 03/05/2012, at 5:58 AM, Jose Carlos Martinez Llario wrote:

> Hi,
> wanted to share a though about improving the topology performance in postgis.
> 
> Many of the functions are using EXECUTE instead of running directly select commands.
> In many cases this is need just because of the used of the schema name  of the topology primitive tables.
> 
> I found between 4 and 10 times improving performance some sentences. I guessing it could be even better.
> 
> My question is if an approach like the following makes sense:
> 
> 1.- With one command we can make the current topology schema the default schema in search path,
> 2.- then working with topology
> 3.- Change search_path again when finishing the spatial analysis.
> 
> (the parameter of the topology name in the functions should be ignored or removed)
> I know it requires a lot of changes but currently the performance of the persistent topology is too slow.
> 
> if one do that many functions can be run without EXECUTE. Spatial analysis between different topologies is not possible which fits the procedure.
> 
> What do you think Sandro?
> 
> Regards,
> Jose
> 
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