I would like to transform the xml data here : http://wiki.openstreetmap.org/wiki/Berlin/Transportation into shape files or load into postGIS.
I think the thing I am missing is how these xmls files, which contains relations, can be used to get the data they represent.
I have tried opening the JOSM link, opening the GPX files in QGIS, and directing to the xml file to osm2shp.jar - none of these routes has given me what I need. The GPX files can be used to generate a shapefile, but when I 'Open Attributes Table' in QGIS all of the column values are NULL for all points. I would appreciate a step by step description of how to work with this data in postGIS or as a shape file.