[OSM-talk] Id stability

Tobias Knerr osm at tobias-knerr.de
Tue Aug 2 12:05:06 BST 2011


Kate Chapman wrote:
> Why aquiesce to use tags at all, making
> data more consistent just burdens *our* data with stuff other people
> want to do with it.

It is impossible to create a map that displays buildings if no one adds
buildings to the database. Adding buildings requires effort, but it is
_necessary_ effort for something that many mappers want our data to be
used for.

Linking to OSM, however, is entirely possible without placing an
additional burden on mappers: Implement a service that resolves queries
for OSM objects. Therefore, manually maintaining IDs in the database is
an unnecessary waste of mappers' time.

Besides the effort required for manual ID maintenance, I think that
manual IDs would even turn out to be semantically questionable. They
cannot easily represent which aspects of the "object" are referenced by
the ID.
If a restaurant moves, should it keep the same ID? If it is renamed? If
it goes bankrupt, is sold, renovated, and reopened by a different owner?
Setting up a query would ideally encode your intentions - do you e.g.
query for "restaurant at address" or "restaurant with name/owner in
town"? A mapper maintaining a restaurant ID has no chance to know the
intentions of people linking to the restaurant, and it is easily
possible that different people even use that same ID with incompatible
intentions.

-- Tobias Knerr



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