Re: Problem with Hash based Linked Data URIs

On 16 Feb 2013, at 16:04, Mo McRoberts <> wrote:

> As should be blindingly obvious to anybody who's worked with them, hash-based URIs are principally useful where a document describes a _single_ entity within its sphere of reference (though the nature of triples and many ontologies is that there may well be parts of descriptions of other things).
> Ontologies/vocabs are a one solid case where it's really not a good idea to use them because it's hard to split them up into separately-served resources later.

I don' think that quite locates the problem at the right place.
It would be completely feasible to have one #uri per vocabulary element, each at
a different location. For example all of DBPedias resource URIs could just return
the content inside so one could have

defined by

That would have the advantage of required half the requests on DBPedia to get 
the information. The only problem I see with that is a syntactic one. I sent 
this to the WebArch and RDF-Comments group as a mail and RDF group in November, 
but got no  answer there yet

I suppose one would need to propose a solution to the problem.
Something allong the lines of requesting a new @prefix in Turtle 
so that one could write:

@pre db: ("" _ "#x")

This would allow one then to have

:j :likes db:Whiskey .

which would be equivalent to

:j :likes <> .

> (Ironically, as a redirecting service, if the PURL for GR had been instead of, it could have redirected to either a hash-based or a hash-less URI  there's no benefit to hash-based URIs if you're always inserting a redirect _anyway_).

My guess is that you don't need these redirects in fact. But anyway, as far as WebID 
goes the point is pretty moot, since as you point out below:

> On the other hand in the case of "this is the document which describes me" or "this is the document which describes this book", it makes a lot of sense to use hash-based URIs because that document has a notion of a primary topic while anything else described is a supporting adjunct. Even if it's aggregated into a dataset, the subject used in that dataset would be a URI which resolves to that one-thing document URI.
> M.
> On Sat 2013-Feb-16, at 14:33, Adrian Gschwend <>
> wrote:
>> On 16.02.13 12:10, Melvin Carvalho wrote:
>>> Hi Kingsley, just trying to understand the problem better.  When I
>>> click, it takes me to
>>> the section of the GR vocab that is related to BusinessEntity (via html
>>> anchors).  What should it be doing?
>> That's only because you requested it from a web browser, if you get that
>> as RDF (via rapper for example) it will make a request to
>> and instead of giving you the answer to
>> what you really want to know  (#BusinessEntity) it downloads the whole
>> ontology which according to rapper is 1834 triples. Everything after the
>> # is handled client side and does not even get through the webserver.
>> This is not handy at all when you start to write code, you get way more
>> than you wanted to know and it gets harder to implement local caching
>> for example. Did that done that, really no fun to implement properly
>> with hash based URIs.
>> So I'm really no fan of hash based URIs either, especially on bigger
>> ontologies/datasets.
>> cu
>> Adrian
>> --
>> Adrian Gschwend
>> @
>> ktk [a t]
>> -------
>> Open Source Project
> --
> Mo McRoberts - Technical Lead - The Space
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Social Web Architect

Received on Saturday, 16 February 2013 15:28:16 UTC