- From: Eric Prud'hommeaux <eric@w3.org>
- Date: Sun, 27 Jun 2004 05:56:32 -0400
- To: Jos De Roo <jdroo@skynet.be>
- Cc: public-rdf-dawg@w3.org
- Message-ID: <20040627095631.GA17819@w3.org>
On Sat, Jun 26, 2004 at 10:08:13PM +0200, Jos De Roo wrote:
>
> EricP wrote:
> > 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:
> >
> >
> +-------------------------+-------------------------+-------------------------+-------------------------+-------------------------+
> > | n|
> d| e|
> f| g|
> >
> |-------------------------|-------------------------|-------------------------|-------------------------|-------------------------|
> > | <http://example.org/n#A>|
> NULL| NULL|
> NULL| NULL|
> > |<http://example.org/n#A2>|
> NULL| NULL|
> NULL| NULL|
> >
> |<http://example.org/n#A3>|<http://example.org/n#D3>|<http://example.org/n#E3>|<http://example.org/n#F3>|
> NULL|
> >
> |<http://example.org/n#A4>|<http://example.org/n#D4>|<http://example.org/n#E4>|<http://example.org/n#F4>|<http://example.org/n#F4>|
> >
> +-------------------------+-------------------------+-------------------------+-------------------------+-------------------------+
> >
> > and this as a ResultSet:
> >
> > @prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .
> > @prefix rs: <http://jena.hpl.hp.com/2003/03/result-set#> .
> >
> > [] rdf:type rs:ResultSet ;
> > rs:resultVariable "n" ;
> > rs:resultVariable "d" ;
> > rs:resultVariable "e" ;
> > rs:resultVariable "f" ;
> > rs:resultVariable "g" ;
> > rs:size "4" ;
> > rs:solution
> > rs:solution
> > [ rdf:type rs:ResultSolution ;
> > rs:binding [ rdf:type rs:ResultBinding ;
> > rs:variable "n" ; rs:value
> <http://example.org/n#A> ] ;
> > rs:binding [ rdf:type rs:ResultBinding ;
> > rs:variable "d" ; rs:nonValue "NULL" ] ;
> > rs:binding [ rdf:type rs:ResultBinding ;
> > rs:variable "e" ; rs:nonValue "NULL" ] ;
> > rs:binding [ rdf:type rs:ResultBinding ;
> > rs:variable "f" ; rs:nonValue "NULL" ] ;
> > rs:binding [ rdf:type rs:ResultBinding ;
> > rs:variable "g" ; rs:nonValue "NULL" ]
> > ] ;
> > rs:solution
> > [ rdf:type rs:ResultSolution ;
> > rs:binding [ rdf:type rs:ResultBinding ;
> > rs:variable "n" ; rs:value
> <http://example.org/n#A2> ] ;
> > rs:binding [ rdf:type rs:ResultBinding ;
> > rs:variable "d" ; rs:nonValue "NULL" ] ;
> > rs:binding [ rdf:type rs:ResultBinding ;
> > rs:variable "e" ; rs:nonValue "NULL" ] ;
> > rs:binding [ rdf:type rs:ResultBinding ;
> > rs:variable "f" ; rs:nonValue "NULL" ] ;
> > rs:binding [ rdf:type rs:ResultBinding ;
> > rs:variable "g" ; rs:nonValue "NULL" ]
> > ] ;
> > rs:solution
> > [ rdf:type rs:ResultSolution ;
> > rs:binding [ rdf:type rs:ResultBinding ;
> > rs:variable "n" ; rs:value
> <http://example.org/n#A3> ] ;
> > rs:binding [ rdf:type rs:ResultBinding ;
> > rs:variable "d" ; rs:value
> <http://example.org/n#D3> ] ;
> > rs:binding [ rdf:type rs:ResultBinding ;
> > rs:variable "e" ; rs:value
> <http://example.org/n#E3> ] ;
> > rs:binding [ rdf:type rs:ResultBinding ;
> > rs:variable "f" ; rs:value
> <http://example.org/n#F3> ] ;
> > rs:binding [ rdf:type rs:ResultBinding ;
> > rs:variable "g" ; rs:nonValue "NULL" ]
> > ] ;
> > [ rdf:type rs:ResultSolution ;
> > rs:binding [ rdf:type rs:ResultBinding ;
> > rs:variable "n" ; rs:value
> <http://example.org/n#A4> ] ;
> > rs:binding [ rdf:type rs:ResultBinding ;
> > rs:variable "d" ; rs:value
> <http://example.org/n#D4> ] ;
> > rs:binding [ rdf:type rs:ResultBinding ;
> > rs:variable "e" ; rs:value
> <http://example.org/n#E4> ] ;
> > rs:binding [ rdf:type rs:ResultBinding ;
> > rs:variable "f" ; rs:value
> <http://example.org/n#F4> ] ;
> > rs:binding [ rdf:type rs:ResultBinding ;
> > rs:variable "g" ; rs:value
> <http://example.org/n#F4> ]
> > ] .
> >
> >
> > * 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 analogous presumption, I plan to introduce foaf:UnPerson
> > without Danbri's consent.
>
> :)
> I was also trying to run your "nested optional arcs" test case
> and had to make some corrections in our implementation so that
> in fact only those 4 results are returned (also using a design
> that allows result interpretation as it refers to the query).
>
> So querying the facts given in
> http://eulersharp.sourceforge.net/2004/04test/ericP.n3
> with filter
> http://eulersharp.sourceforge.net/2004/04test/ericF.n3
> results in
> http://eulersharp.sourceforge.net/2004/04test/ericE.n3
Yeah, the trick (for me, at least) was to make sure I NULL'd
all the otherwise unbound variables in any optional part that
was not satisfied. I think this is pretty easy to define so
I'm not to worried about this as a requirement from that
perspective. However, it is worth noting that introducing
optionals does mean we have an ordered set of constraints.
I'd like to experiment with Euler(sharp?). I guessed a CVSROOT:
cvs -d:pserver:anonymous@cvs.sf.net:/cvsroot/eulersharp login
but didn't guess a module name. I tried Euler, euler, EulerSharp,
and eulersharp.
> Remark the open '?'-marked resources in the results i.e.
> (:A ?d ?e ?f ?g) da:bindingFor < ... /ericF.n3>.
> (:A2 ?d ?e ?f ?g) da:bindingFor < ... /ericF.n3>.
> (:A3 :D3 :E3 :F3 ?g) da:bindingFor < ... /ericF.n3>.
> (:A4 :D4 :E4 :F4 :F4) da:bindingFor < ... /ericF.n3>.
>
> -jos
>
>
> > [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
> > --
> > -eric
> >
> > office: +81.466.49.1170 W3C, Keio Research Institute at SFC,
> > Shonan Fujisawa Campus, Keio University,
> > 5322 Endo, Fujisawa, Kanagawa 252-8520
> > JAPAN
> > +1.617.258.5741 NE43-344, MIT, Cambridge, MA 02144 USA
> > cell: +1.857.222.5741 (does not work in Asia)
> >
> > (eric@w3.org)
> > Feel free to forward this message to any list for any purpose other than
> > email address distribution.
>
> --
> Jos De Roo, AGFA http://www.agfa.com/w3c/jdroo/
--
-eric
office: +81.466.49.1170 W3C, Keio Research Institute at SFC,
Shonan Fujisawa Campus, Keio University,
5322 Endo, Fujisawa, Kanagawa 252-8520
JAPAN
+1.617.258.5741 NE43-344, MIT, Cambridge, MA 02144 USA
cell: +1.857.222.5741 (does not work in Asia)
(eric@w3.org)
Feel free to forward this message to any list for any purpose other than
email address distribution.
Received on Sunday, 27 June 2004 05:56:32 UTC