[OSM-dev] question about node identifiers

[Frank O'Dwyer]

John Smith wrote:
> It's unlikely someone would delete and add a POI in the same spot, 
> they are more likely to be modified.
Cheers, that's what I expected. So I can probably just ignore that case 
for now and run a cleanup script separately later on if needed.
>> I tend to use the minutely ones to keep my DB up to date as much as possible, but I think daily is the longest snap shot available, you could just grab the 7 daily change files if you only wanted to update once a week.
>>     
Is there a recommended way to do this so as not to cause undue load on 
osm servers? Any existing code I could to pull changesets?
> The vast majority of data in changesets is nodes, however most of 
> these wouldn't be amenity nodes, on a half decent machine it doesn't 
> take much to process a daily file through an xml parser to pull out 
> just the amenity changes. Also node changes could turn an amenity into 
> something else if it was tagged wrong so you would need to keep tabs 
> on this and delete them.
Is there already existing ruby code to parse the changesets? So far I've 
been playing around with osmlib but it seems like it only supports .osm 
files.
> There is a list on the Map Features wiki page:
>
> http://wiki.openstreetmap.org/wiki/Map_Features
>   
Cool - exactly what I was looking for - thanks.

Thanks,
Frank