Hello, I'd like to use a CASE Conditional to update a field in OSM road data:
CASE WHEN "type" = 'access_ramp' AND "maxspeed" IS NULL THEN 30 END This means that the field "maxspeed" shall be 30 for the access_ramp column. I inserted the SQL expression above and obvoiusly the CASE WHEN Conditional uses automatically an ELSE function, even if I don't insert one! In my case now the maxspeed only for 'access_ramp' is 30 and all the other features are set to NULL. It seems that the ELSE condition is set to NULL and that all the other data don't get the already existing value from the access_ramp column but are overwritten. I don't want to have the other objects overwritten. Do I always have to use an ELSE expression? In which case can s.o. use the CASE expression only? Does somebody use it in practice? Kind regards, Larissa _______________________________________________ Qgis-user mailing list Qgis-user@lists.osgeo.org http://lists.osgeo.org/mailman/listinfo/qgis-user