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Re: naive question: why prefer absolute URIs to # URIs for linked data?

From: Ivan Herman <ivan@w3.org>
Date: Mon, 29 Aug 2011 13:47:34 +0200
Cc: www-tag@w3.org, Manu Sporny <msporny@digitalbazaar.com>, Harry Halpin <hhalpin@ibiblio.org>, Ian Davis <me@iandavis.com>
Message-Id: <8D1667D4-B8A3-464E-BFC5-CCA691FD8B9A@w3.org>
To: Jonathan Rees <jar@creativecommons.org>
Jonathan,

in my understanding that is related to the follow-your-nose principle. If I see a URI for a, say, predicate, I may want to follow that URI and get some information. That predicate (or class or whatever) is rarely alone, it may be part of a vocabulary.

If the URI is of the form http://blabla#blah, that means that I, typically, have a large vocabulary file at http://blabla and #blah is somewhere there. So if I dereference http://blabla#blah, I will get the full vocabulary and I will have to locate the specific element #blah to something with it (as a caller). If the vocabulary is very large, that might be a pain.

If the URI is of the form http://blabla/blah, and I dereference it then I can expect to get only the information I am looking for.

There may be other reasons; that is the one which resonates with me, personally...

Cheers

Ivan


On Aug 28, 2011, at 19:27 , Jonathan Rees wrote:

> Question to the broader www-tag readership (and beyond):
> 
> I don't want to start another argument, I just want to understand the
> position that it is necessary to use absolute (i.e. hashless) URIs
> instead of hash URIs for semantic web / linked data purposes, and
> record the reasons for this position somewhere. I attempted this in
> http://www.w3.org/2001/tag/awwsw/issue57/20110625/#hash  but I feel
> the case I made against # URIs there is not convincing.
> 
> That is, suppose you want a URI to use in RDF as a reference (name,
> "identifier", whatever) for something other than the web page
> (document, "information resource", whatever) at that URI. Why is it so
> important that the URI be absolute, instead of one containing # ? So
> important that the defense of this right would precipitate storms of
> email messages, many containing quite strong language?
> 
> This question is at the root of the httpRange-14 / ISSUE-57 dispute,
> since if # URIs worked for everyone there would be no pressure to use
> absolute URIs, and therefore no fight about whether you can use 200 or
> are required to use 303. So I'd like to understand this better than I
> do.
> 
> Please be as specific and concrete as possible. I promise to do my
> best to listen patiently, treat all reasons as legitimate, and report
> impartially.
> 
> Thanks for your help,
> 
> Jonathan
> 


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Ivan Herman, W3C Semantic Web Activity Lead
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Received on Monday, 29 August 2011 11:44:56 GMT

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