[Tagging] part_of:wikidata key

[Christoph Hormann]

On Tuesday 28 November 2017, Kevin Kenny wrote:
> >
> > Great! Let us know when you have a working solution, consensus to
> > implement it, and tools that work with it.
>
> Having nonvolatile ID's for ways really is technically infeasible.
> Ways get split and recombined all the time, and their ID's will never
> be stable.

This is just a question on editors managing that.  Right now the 
inheritance of IDs is usually not a conscious choice of the mapper but 
if this is deemed desirable this could be changed.

I don't really see the advantage of wikidata IDs in that scenario.  If i 
have two ways with different wikidata tags and i want to merge them i 
also have the problem of determining which of the three possible 
variants is correct.  Same if i want to split a way with a wikidata tag 
(four different variants here if you assume both can also get the same 
ID).

The only advantage i see is from the wikidata side that the 
responsibility of dealing with a data change is superficially delegated 
to the mapper in OSM with wikidata tags but it is an illusion that this 
will actually lead to reliable ID maintainance since ultimately this is 
something you cannot require the mapper to do because it is 
non-verifiable information.  OSM recruits mappers to map the verifiable 
world, we do not require them to also research secondary source 
references in wikidata to make sure they correctly maintain wikidata 
IDs.

-- 
Christoph Hormann
http://www.imagico.de/