[OSM-talk] How to deal with versioning

[Ed Avis]

Martijn van Exel <m <at> rtijn.org> writes:

>1    A building object is being imported from an open public sector dataset
>2    The building receives some modifications by human contributors
>(attributes, geometry, or both)
>3    A new version of the public sector data becomes available and is imported.
>
>Currently, in step 3. the human contributions would be lost,

This is why doing an 'import' of external data is not possible, except when there
is no existing data in OSM that overlaps.  Rather, the external data needs to be
reconciled against OSM and 'merged' rather than imported.  Conflicts would
usually need to be fixed manually.

However, for specialized data you can tag in a separate namespace where it's
generally understood that changes should be made in the upstream data source
(and thus fed back to OSM in due course) rather than in OSM directly.  The
NaPTAN bus stop import in the United Kingdom is like this: it uses 'naptan:'
tags which are not changed by mappers directly.  However, that setup is not an
option for bread-and-butter things like road layout and naming, where we want
everybody to be able to edit the map.

-- 
Ed Avis <eda at waniasset.com>