Hi, I don't get to use sql server too much, so I don't have any definitive answers for you.
But based upon ogrinfo the geom type & projection are unknown, and mapnik needs to know what these are. This may provide the answer for you- http://woostuff.wordpress.com/2011/06/07/opening-ms-sql-server-2008-spatial-tables-in-qgis-correctly/ It would be nice to know if you get this working. kind regards. On Fri, Jun 17, 2011 at 2:41 AM, Alastair Aitchison <[email protected]>wrote: > Dear all,**** > > ** ** > > Mapnik newbie here. After a few headaches, I’ve managed to compile Mapnik > and its dependencies to run under Windows, and I can successfully run the > rundemo.py script to create a beautiful map. :)**** > > However, I’m a bit stuck at the next step. My source data is held in SQL > Server 2008 - in separate tables for polygon, polyline, and point layers, > stored using the geometry datatype. **** > > ** ** > > I didn’t expect Mapnik to have a dedicated MSSQL driver, but notice that it > does have support for OGR datasources and, since GDAL 1.8 supports > MSSQLSpatial as a datasource ( > http://www.gdal.org/ogr/drv_mssqlspatial.html), I thought I’d be able to > connect via that. So, I tried defining a VRT virtual layer that retrieved > the Well-Known Text of one layer, as follows:**** > > ** ** > > <OGRVRTDataSource>**** > > <OGRVRTLayer name="AASQLlayer">**** > > <SrcDataSource> > MSSQL:server=.\SQLEXPRESS;database=OSVectorMap;trusted_connection=yes</ > SrcDataSource> **** > > <SrcSQL>SELECT geom27700.STAsText() AS geomWKT FROM > TG11_Settlement_Area</SrcSQL>**** > > <GeometryField encoding="WKT" field="geomWKT"/>**** > > </OGRVRTLayer>**** > > </OGRVRTDataSource>**** > > ** ** > > Testing the OVF file above with ogrinfo seemed to suggest that the > connection string was ok, and reported the following:**** > > C:\OSGeo4W\apps\mapnik\alastair\python>ogrinfo -so -al mssql.ovf**** > > INFO: Open of `mssql.ovf'**** > > using driver `VRT' successful.**** > > ** ** > > Layer name: AASQLlayer**** > > Geometry: Unknown (any)**** > > Feature Count: 1488**** > > Extent: (610000.000001, 309999.999990) - (620000.000001, 319999.999992)*** > * > > Layer SRS WKT: (unknown)**** > > geomWKT: String (0.0)**** > > ** ** > > I then used this VRT as the datasource of a new layer in the rundemo.py > script:**** > > new_lyr.datasource = mapnik.Ogr(file='MSSQL.ovf',layer="AASQLlayer")**** > > ** ** > > However, trying to render the map gave me the following error:**** > > ERROR 1: Failed to open datasource > `MSSQL:server=.\SQLEXPRESS;database=OSVectorM**** > > ap;trusted_connection=yes'.**** > > Traceback (most recent call last):**** > > File "rundemo.py", line 73, in <module>**** > > provlines_lyr.datasource = > mapnik.Ogr(file='MSSQL.ovf',layer="AASQLlayer")**** > > File "C:\OSGeo4W\apps\Python25\lib\site-packages\mapnik\__init__.py", > line 418**** > > , in Ogr**** > > return CreateDatasource(keywords)**** > > RuntimeError: Failed to open datasource > `MSSQL:server=.\SQLEXPRESS;database=OSVe**** > > ctorMap;trusted_connection=yes'.**** > > ** ** > > I’ve tried various combinations of changing the VRT to return WKT, WKB, or > SQL Server’s own native geometry format – they all seem to validate ok with > ogrinfo, but fail in mapnik.**** > > ** ** > > Could anyone please offer any advice as to how to connect mapnik to SQL > Server? Thanks all for your time.**** > > ** ** > > ** ** > > _______________________________________________ > Mapnik-users mailing list > [email protected] > https://lists.berlios.de/mailman/listinfo/mapnik-users > >
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