[OSM-talk] Tagging schema

[David Earl]

On 05/10/2009 11:43, Lester Caine wrote:
> Rather than all these separate elements, tag values should form part of 
> the tagkey object, and descriptions can be added at any level. I need to 
> find the link to a good example, but
> 
> <tag name='barrier' type='value' relevantto='node'>
>      <tagvalue name='gate' />
>      <tagvalue name='bollard'/>
>      <tagvalue name='bollards'/>
>      <description lang='en'>one or a series
>      of short posts for excluding or diverting motor vehicles from a
>      road, lawn, or the like</decription>
> <tag/>
> 
> But I suspect this is just a misunderstanding, as a scheme needs to be 
> defined in .xsl. 
> http://www.cabinetoffice.gov.uk/media/260545/BuildingStructure.xml is a 
> good example of a definition of a building with enumerated tag values. I 
> was trying to find the one that goes with 'landuse' but I don't have 
> time ... need to be on the road by 1 ...

You're probably right - this was only a first attempt at suggesting the 
principle.

In practice, the actual representation would be as database tables, and 
this gets exposed through the API as XML. I would think the values would 
typically be in a separate table, which is why I wrote it the way I did, 
but the API doesn't have to deliver it separately as I wrote it.

I think you'd still want to be able to filter descriptions and possibly 
other aspects by selected language to limit the size, but that's a minor 
detail.

David