[OSM-talk] Historic Mapping needs help Now!

[andrzej zaborowski]

2009/8/18 Andy Robinson (blackadder-lists) <ajrlists at googlemail.com>:
> here's my thoughts.
>
> If object is no longer present we need some sort of "ghost" tagging, and the
> ghost tag take precedent when rendering. This means that the data that was
> present is still available, its useful data after all. Ideally there would
> be a start_date and end_date tag also that defines the period when the
> object was present.

I'd opt for somehow reusing the normal object history already handled
by OSM for keeping the object's real world history.  So when you
delete an object from OSM you could set a kind of "deletion tag" that
would either inform that the object was a mistake and shouldn't have
been stored in the DB in the first place or contain the end date of
when the object stopped existing.  The objects contained in planet
snapshots and those rendered would always aim to reflect current state
only, but historic data could be retrieved from history (yay).

On the other hand, if adding new objects in the past is made too easy,
keeping track of vandalism and/or spam in historic data will be quite
a feat.

Cheers