(@imagico skip to 4.6b)

Isn’t 4.6 the most relevant part for most commercial use cases of the ODbL? As Arnulf Christl pointed out today (with the example of SplashMaps) at FOSSGIS 2014 Berlin

a. The entire Derivative Database;

or

b. A file containing all of the alterations made to the Database or the method of making the alterations to the Database (such as an algorithm), including any additional Contents, that make up all the differences between the Database and the Derivative Database.

The Derivative Database (under a.) or alteration file (under b.) must be available at no more than a reasonable production cost for physical distributions and free of charge if distributed over the internet*

There is no need to give the Public access to your precious private data as long as you describe the connector to your Data Source.

If I understood that correctly you don’t even have to expose the underbelly of your original data structure. One could only describe the access to a pruned, generalized, rasterized or otherwise preprocessed proxy Database. The Database does not even have to be accessible online.

Also it’s semantically unclear if giving access to any additional Contents on request by physical mail applies to the distribution method of the derived database or to that of the alteration file.

By no means you have to expose any original data. Also it’s unclear to me if giving access to any additional Contents alters the the license of that content to ODbL (especially regarding reuse rights) or only allows a one time access.

There is a KML/Shapefile containing 30,990! gelocated settlement names here: http://www.unitar.org/unosat/sudan

It is named Gereida/Garienda/Gerida Saadun is just north of it at osm.org/#map=16/11.2950/25.1300