Hi Andre:

On 09/22/2012 03:17 PM, Andre Joost wrote:
Am 22.09.2012 13:47, schrieb Micha Silver:
On 09/22/2012 10:27 AM, Andre Joost wrote:
 Am 22.09.2012 09:17, schrieb Johan Nilsson:

 There is another thing with 'Personal geodatabase' and that is that ESRI
 don't recommend to use it in their documentation because it slow and get
 really slow if they are bigger and the absolute size are limited.

 Yes, that's true. Spatial index will not be possible on MDBs (as well as on
 spataialite). But MS Access is widely spread, so a connection would be highly
 appreciated. And MDBs are easily portable (again, as well as spatialite).
 Thats a great advantage to Postgis.


I'm not sure I understood your comment, but spatial indexing is definitely
supported in Spatialite using the R*Tree structure.

I referred to the spatialite 2.1 manual still first in Google search.


I learned a lot from:
http://www.gaia-gis.it/spatialite-3.0.0-BETA/spatialite-cookbook/html/rtree.html

Also have a look at these blog posts:
http://northredoubt.com/n/2012/01/18/spatialite-and-spatial-indexes/
http://www.surfaces.co.il/?p=1196

I guess its not fully supported by the stable Qgis 1.8.0.
In DB Manager, I have an entry Spatial Index, but get an error
"no such module: VirtualSpatialIndex". Qspatialite throws an error for the same reason, and a message "No spatial index defined".


I have a feeling that QSpatialite is somewhat behind. I'm using spatialite 3.0 with the spatialite_gui 1.5 and there you have access to the new format for making use of spatial indexes.

The problem is that, unlike PostGIS, spatial indexes are not used automatically. After you create a spatial index on a table, you must then construct your query to make use of it. This is certainly non-intuitive for "normal people".

Regards,
Micha


  
I read that spatialitegui might solve the problem, but I want to work inside Qgis. So still nothing for "normal" people ;-)

Using Master I get other errors about missing pyspatialite.

Gruß,
André Joost

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-- 
Micha Silver
GIS Consultant, Arava Development Co.
http://www.surfaces.co.il

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