Am Tue, 02 Aug 2011 15:43:54 +0200 schrieb Frederik Ramm <frede...@remote.org>:
> Hi, > > On 08/02/11 15:21, Gregor Horvath wrote: > > It is a logically inaccurate to delete an ID in such cases. > > What you actually logically do is replacing an ID, or creating an > > alias. The problem is there is no semantic in OSM data to express > > such a move operation. Deleting is the wrong one. Deleting means a > > destroyed house or physically removed street and in this case it is > > logically correct that the ID is gone. > > No. You are entirely mistaken in applying that kind of semantic to > OSM. When a mapper maps a street, or a building, or anything, the ID > is just a throwaway by-product of that process which allows us to > refer to the object internally. The mapper does not willingly say: "I > hereby assign the following ID to you, house, to remain with you > until you are destroyed!" OSM provides uri's to ID's which are linked to names of physical objects. Example: http://www.openstreetmap.org/browse/node/1381574156 IN HTTP world URI's should be stable and a request for a moved object should return an HTTP Status code of 301 ( Moved Permanently) instead of 404 (Not Found). The same logic should apply to OSM ID's/URI's > Deleting an object in OSM only becomes "logically inaccurate" if one > makes the semantic connection that you are making ("deleted object -> > demolished house"), but in fact it is that connection that is > logically baseless. (For example, we would also delete an object if > we find out that it was wrongly imported or taken from an unsuitable > source, just to mention the most obvious examples.) These are also valid cases for a "not found" 404. I am not against deleting at all. There are perfectly valid cases for that. I propose to add the possibility to model a move. (Not a must, like any other tagging in OSM) > > This is an interesting idea that would often make it easier to find > out what someone has done in an editing session - has he shortened > one way and created another new way, or has he simply split one? > > But it should not be confused with ID persistence. > Yes, I am not for total ID persistence, because as I said there _are_ valid cases for deleting an ID. But a move, join or rename is not a delete operation. -- Greg _______________________________________________ talk mailing list talk@openstreetmap.org http://lists.openstreetmap.org/listinfo/talk