On 10 Nov 2010, at 23:31, David Murn wrote: > Just out of interest, are you 100% against OSM keeping recent history > data? If a building is demolished, do you believe that deleting the way > should remove any trace of that from OSM, or do you believe that OSM > should retain a history?
Of course the history trace is a very valuable thing about OSM. By contrast, adding things which don't exist any more - mapping the past - is, as Richard Weait says, orthogonal to OSM. > How long should that history be retained? In 10 years, would you advocate > that any historic data (objects deleted over n years ago) be deleted, to > avoid cluttering the database? If OSM had existed 20 years ago, would you be > advocating that the database be kept clean, so that only current data is in > it? As with any wiki, keep all the edits you can until they overwhelm you. It's not a question of how long to retain edits. I'm no backup expert. FWIW I don't think it's vital that every transformation to every entity in OSM is kept forever. I have no idea how much of a burden it is to the db admins to maintain the history, nor what their projections are for the situation 20 years hence. A proposal that involved selective forgetting of edits would surely be far more subtle and respectful than dumping based merely on age. > OSM, by its nature, is excellent for retaining historic data, for > example if a road is realigned, you have a history that shows how it was > realigned, or if a road changes name, there exists a history of previous > names. Yes, that's a fantastic thing about OSM. >> I'm not sure what you're saying - that 18,000 tag usages is >> insufficient for someone to try to sort out a mess of tag values? > > I read it more as 'this tag already has a range of values and other > uses, do you really have to use it?'. You also have to wonder, of those > 18,000 tags, how many are in your area of interest, and what percentage > of nodes in that area are tagged? Maybe .1% if youve been busy. I understood the tag was started by Frankie Roberto who was specifically interested in adding historic data to OSM. Whether most people are using it in the way he hoped I do not know. What's the relevance of my "area of interest"? Most of the edits there are "(big)", performed by bots whose authors have determined that a tag is being used incorrectly without asking me or other Bristolians. They seem to be doing a good job. - L _______________________________________________ talk mailing list [email protected] http://lists.openstreetmap.org/listinfo/talk
