Hi Karen,
It unfortunately depends on how you define 'thing'. The 'thing' returned by
a web server when you ask the server to resolve a hash *URI of*:
http://id.loc.gov/authorities#geographicNames
will _usually_be an 'information resource' (the correct term although I just
think of it as a document) with the *URL *of:
http://id.loc.gov/authorities<http://id.loc.gov/authorities#geographicNames>
although the server could have been configured to return some 'thing' more
specifically typed like:
http://id.loc.gov/authorities.rdf<http://id.loc.gov/authorities#geographicNames>
According to the rules, that 'thing' returned at that URL should contain
information about all resources identified within that context. So:
http://id.loc.gov/authorities#geographicNames
and
http://id.loc.gov/authorities#conceptScheme
are different resource 'things' but they will be described in the same
document 'thing' returned by the server:
http://id.loc.gov/authorities <http://id.loc.gov/authorities#conceptScheme>
Since an http server has to treat the URI as a URL, the server is obligated
by the http protocol to ignore the fragment after the hash.
So these two 'things' are different URIs:
http://id.loc.gov/authorities/sh2008115565#concept
http://id.loc.gov/authorities/sh2008115565<http://id.loc.gov/authorities/sh2008115565#concept>
but are described by the same 'thing' (a document) returned by that URL, as
far as http is concerned.
As in all things web, your mileage may vary.
The Best Practice Recipes document goes into some detail about how a web
server should be expected to respond to a request to resolve a hash URI:
http://www.w3.org/TR/swbp-vocab-pub/#recipe3
See the part of that section titled: "Testing the configuration"
--Jon Phipps
On Wed, Nov 11, 2009 at 2:36 PM, Karen Coyle <lists_at_kcoyle.net> wrote:
> Quoting Jonathan Rochkind <rochkind_at_JHU.EDU>:
>
> Yeah, that's a confusing thing. The RDF world seems to like using hash
>> URIs to represent things. As far as RDF is concerned, the URI's
>> uniqueness is determined including the hash. Two URIs identical except
>> that they end in two different hashes are two different identifiers as
>> far as RDF is concerned.
>>
>
> So in the example that Ross gave,
>
> <rdf:Description rdf:about="
> http://id.loc.gov/authorities/sh2008115565#concept">
>
> identifies the same thing as:
>
> <rdf:Description rdf:about="http://id.loc.gov/authorities/sh2008115565">
>
> ?
>
> But
>
>
> <skos:inScheme rdf:resource="http://id.loc.gov/authorities#conceptScheme
> "/>
> <skos:inScheme rdf:resource="http://id.loc.gov/authorities#geographicNames
> "/>
>
> do not either identify the same thing as:
>
> <skos:inScheme rdf:resource="http://id.loc.gov/authorities"/>
>
> ?
>
> If so, then, yes, that is very confusing.
>
> --
> Karen Coyle
> kcoyle@kcoyle.net http://kcoyle.net
> ph: 1-510-540-7596
> m: 1-510-435-8234
> skype: kcoylenet
>
Received on Wed Nov 11 2009 - 17:30:45 EST