I'm running up against an issue doing a spatial operation requiring multiple input shapefiles using ogr2ogr and sqlite.
ogr2ogr -f "ESRI Shapefile" output.shp input.shp -dialect sqlite -sql "CREATE VIRTUAL TABLE 'overlap' USING VirtualOGR('overlap.shp'); SELECT ST_SymDifference('input','overlap')"
Where 'output' is my output shape, 'input' is one input shape and 'overlap' is the other input shape. I can't seem to get any output, or if I do, it's just a DBF file? Any assistance?
I suspect it's to do with the Virtual Table not having any geometry but I can't seem to do a "RecoveryGeometryColumn" that actually works.
Both 'input' and 'overlap' have the same projection and overlap nicely in QGIS.
I'm on version "GDAL 1.10.0, released 2013/04/24"
Edit: Fixed typos in my sqlite command
ogr2ogr -f "ESRI Shapefile" output.shp input.shp -dialect sqlite -sql "SELECT ST_SymDifference(GEOMETRY,'overlap.sqlite.GEOMETRY'),* FROM input"
Just returns the input shape. I think I've completely missed something obvious...