[OSM-talk] Tagging OSM objects with UUIDs

[Frederik Ramm]

Hi,

John Smith wrote:
> You misunderstood, I wasn't talking about people tagging stuff moving
> across town, I was talking about the thing they tagged moving across
> town. 

Yes. And thereby a link might, or might not, lose its meaning.

> Also the current proposal suggests using multiple UUID tags if
> needed one for the occupant, one for the building in case they need to
> be split, if you only have one UUID and Flickr refers to the building
> and wikipedia refers to the occupant, who gets to keep the UUID if the
> occupant shifts?

This could lead to an inflation of UUIDs on the object, and everyone who 
changes the object will have to decide which of them to keep, which to 
move, which to delete. For example, a restaurant would have one UUID for 
the building it is in, one UUID for the chef, one UUID for the pretty 
barmaid and so on - one UUID indeed for every single property someone 
wants to link to. Then if you, as a mapper, find that the restaurant has 
moved across town you'll have to find out what to do with these UUIDs 
(or, more likely, you'll just leave them alone).

>> For every kind of object and every context in which you link to it, the
>> change of some properties might invalidate the link. That's why UUIDs are
>> not only clumsy but also not solving the problem.
> 
> I fail to see your point here, why would changing properties cause
> problems with UUIDs that are allocated independently of the existing
> OSM ID information?

Because if you link to a restaurant because it has a nice location, then 
changing the location would mean that the link is invalidated; if you 
link to the restaurant because of the chef, then not. You might also 
link to a restaurant because of the name (e.g. "Surprisingly, Hamburg 
has three restaurants named 'Chez something'...") - in which case the 
link would have to survive a move and a change in chefs but not a change 
in name.

Is German English really so different from Australian English ;-)

Bye
Frederik