[OSM-talk] Proposed mechanical edit: Empty Relations

[andrzej zaborowski]

On 13 April 2012 11:12, Paul Norman <penorman en mac.com> wrote:
> Through editor errors or other mistakes there are a number of relations in
> OSM which have no members. I propose a mechanical edit to delete these where
> they are not members of some other way. My proposed procedure, documented at
> http://wiki.openstreetmap.org/wiki/Mechanical_Edits/pnorman_imports is to
> identify these with my pgsnapshot database and delete them if they aren't
> referenced by any other relation.
>
> If they are referenced by another relation I will investigate them and deal
> with them manually.
>
> I've investigated a few of them and they appear to be caused by people
> deleting ways from multipolygons but not deleting the relation. I don't want
> to investigate all 5200 by hand so I'm proposing the mechanical edit.
>
> I will filter out ones touched in the last 24 hours to avoid conflicting
> with anyone.

This thread comes up every some time
(http://lists.openstreetmap.org/pipermail/dev/2009-August/016658.html,
http://lists.openstreetmap.org/pipermail/talk/2010-November/055075.html).
 In 2009 I ran a very similar operation with 4.5k relations deleted as
discussed in the first thread I linked.  The lesson from it was that
some relations are referenced from outside of the database, mainly
from the OSM wiki.  Those should not be deleted automatically either
or it'll upset some users.

Cheers