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Re: PROV-ISSUE-53 (sparql-query-is-overkill): can't we have a lighter method to retrieve provenance-uri, given a document uri? [Accessing and Querying Provenance]

From: Graham Klyne <GK@ninebynine.org>
Date: Fri, 29 Jul 2011 07:44:14 +0100
Message-ID: <4E3256BE.30208@ninebynine.org>
To: Reza B'far <reza.bfar@oracle.com>
CC: Provenance Working Group WG <public-prov-wg@w3.org>
OK, I'll work on something like that and transfer and adapt the SPARQL stuff to 
section 4 (provenance querying).

I'll assume that only the simplest discovery case is needed; i.e. have URI of 
entity, what to get URI(s) for its provenance.

(The other case that used other forms of identification to locate provenance 
will get dropped from 3.4, since that was really just showing how to exploit 
SPARQL capabilities)


Reza B'far wrote:
> As an implementer, I strongly agree with Luc.  REST-base http protocol with minimal payload is a much more likely first option.  Also, it's not necessary that provenance is stored in a traditional notion of a database.  I guess folks call many various persistence mechanisms these days a database, but some of these (say simple files, LDAP, etc) map mug easier to a simple API with just GET's or something like that.
> Usage of SPARQL is still very limited to sem web specialists (compared to simple REST/http/minimal)
> Best
> On Jul 28, 2011, at 8:04 AM, Graham Klyne <GK@ninebynine.org> wrote:
>> SPARQL might well be considered overkill if you had to implement it from scratch.  But there are now many SPARQL toolkits that doesn't seem to be such an issue.  If you do a REST interface, it would likely be backed by some kind of database, so not so much complexity saving there.
>> I think there's a case for defining a simple REST API that might be implemented over a SPARQL store using an LDA (http://code.google.com/p/linked-data-api/wiki/Specification) toolkit, or by other means.  It's not clear to me if that would receive more developer attention.  Maybe for the time being we might define both (REST and SPARQL) and review them as we approach candidate recommendation.  (Oh, but that won't apply to the PAQ, will it?)
>> (BTW, SPARQL is not inherently non-RESTful for simple queries.)
>> #g
>> --
>> Provenance Working Group Issue Tracker wrote:
>>> PROV-ISSUE-53 (sparql-query-is-overkill): can't we have a lighter method to retrieve provenance-uri, given a document uri? [Accessing and Querying Provenance]
>>> http://www.w3.org/2011/prov/track/issues/53
>>> Raised by: Luc Moreau
>>> On product: Accessing and Querying Provenance
>>> Isn't it too onerous to require third parties to provide sparql endpoints, simply to answer the query illustrated in http://dvcs.w3.org/hg/prov/raw-file/default/paq/provenance-access.html#third-party-services  (give the provenance-uris for this resource)?
>>> Stian had suggested a REST service to answer this query, encoding the URL as an argument passed to the service. I had outlined a variant with GET instead of POST.
>>> Some implementers may not use an RDF serialization of provenance, and therefore, it would be good to have a non-SPARQL approach for finding a provenance URI.
Received on Friday, 29 July 2011 08:27:49 UTC

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