[OSM-dev] Alternative PostgreSQL Schema
brett at bretth.com
Wed Oct 24 15:30:20 BST 2007
Martijn van Oosterhout wrote:
> On 10/24/07, Brett Henderson <brett at bretth.com> wrote:
>> An OSM data element's visible status may change many times over its
>> lifecycle. A visible flag of false is a logical delete, but records can
>> be undeleted on a subsequent version. The visible flag on the history
>> tables doesn't indicate which data is current.
> Oh? Last time I tried it wasn't possible to undelete things. Did this
> change with the 0.5 port?
> Have a nice day,
Probably not. I'm just basing this on the data I found in the old
database schema. I'm pretty sure node 2 was one of the nodes that had
been deleted and re-created again. If it is no longer possible then
that is probably good news, it complicates many things. If undelete is
never required it might simplify things considerably.
One other thing I've been thinking about is changeset grouping for the
purposes of reverting changes. If that gets introduced one day it might
be neat to be able to restore old ids. Not sure if that should be
catered for or not.
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