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Re: RDF 2.0 Wishlist - Legal RDF which I can't SPARQL

From: Paul Gearon <gearon@ieee.org>
Date: Thu, 29 Jul 2010 10:25:30 -0400
Message-ID: <AANLkTinf3z1_jzBnKn9PHFYYyH1w5w7c38e530zmJusd@mail.gmail.com>
To: Mischa Tuffield <mischa.tuffield@garlik.com>
Cc: Damian Steer <pldms@mac.com>, Semantic Web <semantic-web@w3.org>
On Thu, Jul 29, 2010 at 10:05 AM, Mischa Tuffield
<mischa.tuffield@garlik.com> wrote:
> Do you think that the same logic should be applied to rdfxml too ? Otherwise
> there will be things you can write in turtle and not in rdfxml which you can
> subsequently sparql, which simply doesn't feel right to me.
> I wonder if I should contact the current sparql working group, as they are
> currently active, and see how they respond. I think it is unfortunate that
> you can write valid rdf which can't be queried in sparql.


Well it's reasonably well known that it's possible to write N3 that
can't be encoded in RDF/XML, and that doesn't seem to have caused
great stress until now. Personally, I *much* prefer N3, so it doesn't
bother me what RDF/XML can't do.  :-)

As for being queried in SPARQL, that's a relative concept. Yes, you
can't match it directly, as you've pointed out, but it can still be
returned in results (unless an implementation specifically tries to
put the data into an internal IRI and a validation error occurs, but
that's implementation specific). It's always possible to bind it to a
variable and return the data. Alternatively, if you really did want to
search for it, you could bind to a variable, and FILTER on its string
representation. Yes, it will be slow, but my point is that the
language isn't *completely* deficient (complain to Steve if it is).

Paul Gearon
Received on Thursday, 29 July 2010 14:26:09 UTC

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