[OSM-talk] Orphaned Relations

Sarah Hoffmann lonvia at denofr.de
Wed Jul 20 17:56:19 BST 2011

On Tue, Jul 19, 2011 at 03:03:53PM +0200, andrzej zaborowski wrote:
> On 17 July 2011 23:55, Sarah Hoffmann <lonvia at denofr.de> wrote:
> > I recently stumbled upon some empty route relations, so I had a
> > closer look at the OSM planet and found that there are about
> > 10.000 orphaned relations in the database and the number is growing.
> >
> > With orphaned I mean relations that have no members and are not
> > member of any other relation. Some are completely empty but most
> > still have some tags. I have created a list of the relations sorted
> > by last editing user here:
> ...
> >
> > Question remains what to do with the existing orphaned relations.
> > Is there any legimate use for them or would it be save to simply
> > delete them all?
> So I had stumbled on the same fact about a year ago and after some
> discussion on this list I deleted about 8000 empty/orphaned relations.
>  It seems all except a handful of those 8000 relations had indeed been
> left in the not-deleted state by mistake.  There were a couple (<5)
> that had still been referenced from the wiki, rather than from inside
> the database through other relations.  I got a couple of e-mails
> months later asking about those relations and undeleted them, it would
> probably be a good idea to check for references in the wiki beforehand
> this time.  I don't think it makes sense to create such empty
> relations before any members are added to them because it's quite
> likely someone else is going to create a duplicate, but I don't have a
> strong opinion and being in the losing position as an author of an
> automated edit I didn't want to argue with the creators of these
> relations.

I must have missed that discussion. 

So I gather it is pretty pointless to try and fix the database
if new empty relations arrive with a rate of about 30 per day,
time is better spent improving editors and/or creating 
a service where people can find their lost relations again. I'll 
look into it.

A more final solution to the problem would be to reject empty
relations on the API side. But that still requires fixing the editors
first. Maybe something for API 0.7.


More information about the talk mailing list