On Friday 27 May 2016 12:09:42 Jukka Rahkonen wrote: > Hi, > > User in gis.stackoverflow tried to use SQL "select ST_Union(geometry)" for > the Natural Earth SQLite db file from > http://naciscdn.org/naturalearth/packages/natural_earth_vector.sqlite.zip. > > The query yields an empty geometry because the NE database is written with > FDO geometries instead of SpatiaLite geometries. What I wonder is that does > GDAL user have any simple mean for getting informed if SQLite db is FDO or > Spatialite.
This probably doesn't completely fullfil the requirement of "simple mean" ;-), but if you enable the debug messages from GDAL with "--debug on", you should see : "OGR style SQLite DB found !" whereas a Spatialite one will trigger : "SpatiaLite v4 DB found !" (or "Spatialite DB found" for spatialite 2 or 3) > If SpatiaLite is present a clever enough user can use ogrinfo > and check from > https://www.gaia-gis.it/gaia-sins/spatialite-sql-latest.html#p16fdo that > value 2 is returned in case when "both tables exist, and their layout is the > one used by FDO/OGR" > > ogrinfo -sql "select CheckSpatialMetaData()" > natural_earth_vector.sqlite > INFO: Open of `natural_earth_vector.sqlite' > using driver `SQLite' successful. > > Layer name: SELECT > Geometry: None > Feature Count: 1 > Layer SRS WKT: > (unknown) > CheckSpatialMetaData(): Integer (0.0) > OGRFeature(SELECT):0 > CheckSpatialMetaData() (Integer) = 2 > > > However, the one who knows to do that must be somewhat advanced GDAL and > Spatialite user. > > -Jukka Rahkonen- > > _______________________________________________ > gdal-dev mailing list > [email protected] > http://lists.osgeo.org/mailman/listinfo/gdal-dev -- Spatialys - Geospatial professional services http://www.spatialys.com _______________________________________________ gdal-dev mailing list [email protected] http://lists.osgeo.org/mailman/listinfo/gdal-dev
