Geometric Indices?

[thompson4822]

I'm trying to compare Spatialite to H2GIS. With the existing Spatialite DB, there is a linestring, and a index composed of the linestring's min/max x and min/max y and id. In order to do a performance comparison, I need to know if there is a way to do something similar in H2GIS.

Let me know and best regards,


Steve Thompson

[nicolas-f]

Hi,

If you are talking about spatial index (query performance should be based on that) :

You have a sample here http://www.h2gis.org/docs/dev/spatial-indices/

If you are looking for spatial functions that read the geometry properties :

http://www.h2gis.org/docs/dev/ST_XMax/
http://www.h2gis.org/docs/dev/ST_XMin/
http://www.h2gis.org/docs/dev/ST_YMax/
http://www.h2gis.org/docs/dev/ST_YMin/

I don't know what is Id, but you can create an auto increment primary key using the h2 database serial column type :

http://www.h2database.com/html/advanced.html#spatial_features

Best regards,

Nicolas FORTIN

Développeur d’applications - AI
Laboratoire d’Acoustique Environnementale (LAE)
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