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Re: tests and inference?

From: Seaborne, Andy <andy.seaborne@hp.com>
Date: Thu, 16 Dec 2004 13:42:32 +0000
Message-ID: <41C190C8.8060607@hp.com>
To: "Thompson, Bryan B." <BRYAN.B.THOMPSON@saic.com>
Cc: 'Dan Connolly ' <connolly@w3.org>, 'RDF Data Access Working Group ' <public-rdf-dawg@w3.org>, "Bebee, Bradley R." <BRADLEY.R.BEBEE@saic.com>



Thompson, Bryan B. wrote:
> Andy,
> 
> So, would you agree that, as things stand, we can not have test cases for
> the
> functional performance of a SPAQL server as part of the spec?

I was talking about the query language, not the protocol.  Testing servers is 
about protocol.  What is not covered in testing functional performance that is 
not covered by issuing queries and checking the results?  Example?

I'll defer on what we are doing about testing the protocol - it's harder (not 
impossible) than testing just the query language as it is built on several 
different components which interact (HTTP, networking, the query processor).

> 
> If so, then I think that this is an issue that needs to be addressed.  The
> simplest path would be to specify conformance for servers with no inference,
> and then leave clients on their own when the server was performing
> inference.
> 
> I also think that this issue is sufficiently important that DAWG might re-
> consider a means in the protocol for the client to demand NO inference,

Coudln't that be done by asking a different service?  An RDF graph is the unit 
being queried (or collection of graphs in the case of SOURCE).  If a publisher 
wishes to provide access to both inference and non-inference versions of some 
information, then this can be achieved by having two services.  If the publisher 
does not wish to do that, then let's allow that choice as well.

 > if
> only so the client could establish a baseline against which to understand
> whether or not the server was performing correctly.

I don't completely understand this - "performing correctly" means returning the 
right answers.

If the testing is by the information publisher, then they can choose to do this 
(internally to their deployment) how they want.   No protocol defined feature 
necessary.

If the testing is by a regular client, then I don't understand what acess to the 
non-inference version achieves.  The service is query over one of more RDF 
graphs.  How those graphs come about is an implementation matter and a matter 
for what the publisher chooses to make available.  I don't think we need define 
("an implementation must provide to be compliant") a feature, leave it to teh 
publishers to decide what services to make available.

	Andy

> 
> As you say, there is no means to have functional tests in the broader realm
> of server-based inference.
> 
> -bryan
> 
> -----Original Message-----
> From: Seaborne, Andy [mailto:andy.seaborne@hp.com] 
> Sent: Thursday, December 16, 2004 7:59 AM
> To: Thompson, Bryan B.
> Cc: 'Dan Connolly '; 'public-rdf-dawg-request@w3.org '; 'RDF Data Access
> Working Group '; Bebee, Bradley R.
> Subject: Re: tests and inference?
> 
> 
> 
> 
> Thompson, Bryan B. wrote:
> 
>>Based on my current understanding, the client is not able to either be 
>>informed concering what inferences the server may draw, nor is able to 
>>constrain what kinds of inference the server may perform.
> 
> 
> Not within the query language itself.
> 
> For the description of capabilities:
> 
> Such information could be recorded in RDF in a service description.  This
> would 
> seem to be the way to get any information relating to the service made
> available 
> - assert some RDF facts.
> 
> Like RDF assertions about any document - we (DAWG) don't need to provide a 
> mechanism to find, publish, change, sign, ... such information as it can be
> a 
> regular RDF graph somewhere.
> 
> For the constraining of queries:
> 
> Different services would offer different capabilities.  I think the spectrum
> of 
> possibilities is wide enough that there is no fixed set we could define now
> and 
> be useful - implementations don't fall into a neat set of a few classes of 
> functionality.
> 
> 	Andy
> 
> 
>> Given this,
>>how can SPARQL tests be written that could be used to demonstrate 
>>(non-) conformance by SPARQL processors that perform inference?
>>
>>-bryan
>>
> 
> 
Received on Thursday, 16 December 2004 13:42:48 GMT

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