- From: Seaborne, Andy <andy.seaborne@hp.com>
- Date: Mon, 28 Jun 2004 15:49:56 +0100
- 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 UTC