On Saturday 14 December 2019, matthias.straetl...@buerotiger.de wrote: > > existing OSMF community guidelines suggest spatial operations like > > ST_Difference() and ST_Intersection() yield Derivative Databases > > that are subject to share-alike. > > Let's take the Collective Database Guideline, you've mentioned: > https://wiki.osmfoundation.org/wiki/Licence/Community_Guidelines/Coll >ective_Database_Guideline_Guideline > > "Technically a reference between non-OSM and OSM data can be by a > database key or any other method of identifying a specific OSM or > non-OSM element that may be used with a database join." > > So actually, I just need to create a collective database, put the > non-free data in one table and OSM data in another. For table > joining, I'm using ST_Intersects() and I'm fine?
No, the quoted guideline says that share-alike does not apply if OSM data and non-OSM data *do not* reference each other and in specific other cases. None of these cases covers references through spatial relationships. The idea that your process of intersecting non-OSM data with OSM based admin polygons results in a collective database is not realistic. To me this kind of operation would be a textbook example of something generating a derivative database - you combine OSM data with non-OSM data to generate something of additional value compared to either of these data sets alone. This is exactly the kind of scenario share-alike is meant for and why it was chosen as license for OSM. But there are of course fairly strong economic interests for this not being subject to share-alike so people think of ways to interpret the ODbL accordingly. -- Christoph Hormann http://www.imagico.de/ _______________________________________________ legal-talk mailing list legal-talk@openstreetmap.org https://lists.openstreetmap.org/listinfo/legal-talk