[OSM-talk] Nominatim & US places

[Brian Quinion]

> it's not really leading anywhere, in part due to the fact that
> noone from Nominatim has spoken up. i did just review the

Hi.  Yes, I've been off doing new year type things.  I'm playing
catchup on my email now - and I've still got a hangover so please
accept my apologies if anything is incoherent.

First of all I'm already working on a lot of this - I'm aware of the
US address problems and working on improving the code and adding extra
data (i.e. tiger) to improve the quality so it may just be sensible to
ignore the whole problem for a couple of weeks and see what happens.

> Nominatim stuff i found in the wiki. they want postal code
> polygons in the database; in the US this is the extremely iffy
> zip code boundary stuff that probably shouldn't go in. i think
> there are some architectural issues to be resolved, but this is

If postcode polygons don't work use 'addr:postcode' on roads or
buildings/properties.  There are also special tiger:zip tags from the
initial import which I've recently added support for which should go
live shortly.

> but i did find a workaround. i added
> is_in=Averill Park, NY, US

The post towns idea in the US isn't one that nominatim currently
supports and it would probably be better to work out a correct way of
tagging this rather than missusing the existing tags.

I'm vaguely aware of the issue - but it would probably be better for
tagging suggestions to come from the US community who understand the
situation on the ground. A couple of possible suggestions: additional
boundaries tagged 'boundary=posttown' or tagging streets with
addr:city but both of these would need code added to nominatim for
them to work properly and should ideally be done in such a way as not
to disrupt other data users.

> what i still don't get is how it figures out the correct zip code of 12018
> for the displayed result string, i guess there's some research to be
> done yet.

I've back ported some code from the new version a couple of weeks back
which tries to improve postcode handling for addresses but this is
just the first stage.  Really I think the zip code stuff is pretty
much a solved problem (or will be shortly)  the post town issues are
probably more significant.

--
 Brian