[OSM-dev] Augmented Diffs

[Roland Olbricht]

> A few questions...
> 
> When the change on a node or way is just a tag change and does not
> involve geometry change, are the diff still providing all linked
> nodes/ways ?

Yes, they do.

Thank you for pointing this out.

I think it would be resonable to not include a way when the only change is a 
tag change of the connected node. However, the opposite is may or may not 
apply:

Imagine somebody runs a database of all italian restaurants in Paris. He 
stores for each way that is the outline of an italian restaurant the center 
coordinates.

Now somebody reclassifies a restaurant from whatever to italian, or corrects a 
typo like cuisine=italien to cuisine=italian. Then the database maintainer 
cannot derive the coordinates of the way because the underlying nodes are not 
contained in the augmented diffs.

Of course you could argument that the same applies to relations, and that the 
database maintainer could ask for all nodes once he knows that a relevant 
restaurant appeared.

So a general question to all: should we keep off the nodes of ways that have 
not changed their geometry?

Cheers,

Roland
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