[OSM-dev] OSM Data Update

[Jim Brown]

Ok, that is exactly right.  :)

An object in the system will never change it's ID but it can be  
replaced with a new object (representing the same real world thing)  
that has a new id.

Jim Brown -CTO CloudMade

(Sent from my iPhone)


On 31 Mar 2010, at 08:00, "Frederik Ramm" <frederik at remote.org> wrote:

> Hi,
>
> Jim Brown wrote:
>> Frederik wrote:
>>> You should never assume that OSM Way IDs (or indeed any IDs) remain
>>> unchanged. The "data" layer on www.openstreetmap.org is your  
>>> friend if
>>> you want to find out the history of a particular stretch of  
>>> motorway.
>>
>> If the ids change it makes diff processing a bit difficult...
>
> Full diff processing will be unaffected if someone deletes a stretch  
> of
> motorway and re-creates it with a different id.
>
> It is only if you would, for example, import all motorways into your  
> own
> database and then try to process diffs regarding these, without
> processing diffs that would create new motorways. In that case, if
> someone deletes something and re-creates it, you will lose it.
>
> Bye
> Frederik