[OSM-newbies] New or existing relation?

[David ``Smith'']

On Mon, Jun 7, 2010 at 5:31 PM, Bob Hawkins <bobhawkins at waitrose.com> wrote:
> SomeoneElse,
> Thanks for your helpful response.  I take on board you are not a JOSM user,
> and if that means you cannot answer this post, I hope another 'someone else'
> can!
> I wish to add a relation to part of the Chiltern Way near Henley-on-Thames.
> 'Chiltern Way' is listed under 'Table of other routes' in the page of the
> link you included. The 'Route relation' column provides its id 23309, and
> "b" and "a" in the 'Route relation' column provide the key and value
> information I need.  What I do not understand, however, is how my part of
> the route will be given the same id as that already in existence in another
> part of the country.  I have carried out a small test in the dialog that
> appears when I choose to create a new relation, by entering the same keys
> and values as for the existing Chiltern Way.  Clicking 'OK' in the dialog
> adds the new relation to the relations list, but with '[id: 0]'.  I am
> unwilling to upload the data until I know how and when the id is added, and
> whether it will be given the same id as for the existing Chiltern Way, based
> upon its name being the same, perhaps.

Anything in JOSM that appears with an id of 0 is a new object, which
will be created in the OSM database and given a unique id when
uploaded.  It will not be merged with anything else.  Since you know
the id of the relation you want to add to, you can tell JOSM to load
that relation specifically.  In the file menu, choose "Download
Object..." .  With that dialog, you can download any node, way, or
relation whose id you know.  If you check "download referrers," you
will also get any way or relation which includes the node, way, or
relation you've selected.  (Ways include, or "refer to", nodes;
relations can include nodes, ways, or even other relations.)  By the
way, there's also a separate command in the File menu "Download parent
ways/relations" which will download any way or relation that refers to
selected already-loaded objects.  That can be quite useful.  Anyway,
once you have downloaded the relation you want to add to, select the
objects you want to add to it, then use the Relation Editor to add
those objects to the relation.

-- 
David "Smith"
a.k.a. Vid the Kid
a.k.a. Bír'd'in

Does this font make me look fat?