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RE: test case results expressed in ResultSet terms

From: Seaborne, Andy <andy.seaborne@hp.com>
Date: Mon, 28 Jun 2004 15:49:56 +0100
Message-ID: <E864E95CB35C1C46B72FEA0626A2E80803615E3D@0-mail-br1.hpl.hp.com>
To: "Eric Prud'hommeaux" <eric@w3.org>, public-rdf-dawg@w3.org

-------- Original Message --------
> From: Eric Prud'hommeaux <>
> Date: 26 June 2004 05:25
> 
> A while back, AndyS and some others settled on a scheme defining
> ResultSets [1]. This seems like work we can use for expressing the
> expected results for a given query.
> 
> RDF Query and Rules Framework [2] leans on this schema and I've
> mostly* adopted this for the Algae tests. The Optional2 test [3],
> which is already in the test cases, looks like this as a table:
> 

<snip/>

> * I've substituted rs:nonValue** "NULL" for rs:value rs:undef in
>   order to distinguish the case where I got no bindings from the
>   case where I got a binding to the resource rs:undef.

In writing test cases for BRQL, I came to the same conclusion that
rs:undefined is not helpful because queries over result sets are confusing.

An alternative approach to having rs:noValue is to just not record nothing
for an unbound variable.  The approach of an explicit "rs:noValue" is good
for positively stating that there is no such binding; absence of rs:value is
better when working with the result set inside a query system as it is built
up.

> 
> ** In analogous presumption, I plan to introduce foaf:UnPerson
>    without Danbri's consent.
> 
> [1] http://jena.hpl.hp.com/2003/03/result-set
> [2] http://www.w3.org/2001/11/13-RDF-Query-Rules/terms
> [3]
>
http://dev.w3.org/cvsweb/perl/modules/W3C/Rdf/test/Optional2-alg.sh?rev=HEAD
&content-type=text/x-cvsweb-markup
Received on Monday, 28 June 2004 10:50:23 GMT

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