[OSM-dev] [OSM-legal-talk] license change effect on un-tagged nodes

[Anthony]

On Wed, Jul 6, 2011 at 7:14 PM, Dave F. <davefox at madasafish.com> wrote:
> On 06/07/2011 21:04, Anthony wrote:
>>
>> On Wed, Jul 6, 2011 at 3:57 PM, Frederik Ramm<frederik at remote.org>  wrote:
>>>
>>> Dave F. wrote:
>>>>
>>>> If one of these gets moved then the whole way gets updated,
>>>
>>> No.
>>
>> Substantively, that is what happens, but technically, in the database,
>> it is not.
>>
>> In the database, we go from:
>>
>> <way id=1><nd id=8><nd id=9><nd id=10></way>
>> <node id=8 lat=82 lon=18 />
>> <node id=9 lat=81 lon=18 />
>> <node id=10 lat=81 lon=17 />
>>
>> to:
>>
>> <way id=1><nd id=8><nd id=9><nd id=10></way>
>> <node id=8 lat=81 lon=17 />
>> <node id=9 lat=80 lon=17 />
>> <node id=10 lat=80 lon=16 />
>>
>> Of course, I think that obviously this:
>> <node id=8 lat=81 lon=17 />
>> <node id=9 lat=80 lon=17 />
>> <node id=10 lat=80 lon=16 />
>>
>> is a derivative of this:
>> <way id=1><nd id=8><nd id=9><nd id=10></way>
>> <node id=8 lat=82 lon=18 />
>> <node id=9 lat=81 lon=18 />
>> <node id=10 lat=81 lon=17 />
>>
>> (assuming a way with, say, 1000 nodes rather than 3...where between 3
>> and 1000 you can stop, well, that's a different question)
>
> Well, I learn something new every day.
>
> This explains a lot - as to why entities keep moving but there's no record
> of it.
>
> Can someone please explain the logic of not recording major changes in the
> database such as shifting an entity?

I suggest you ask that question on the dev list.