- From: Ivan Herman <ivan@w3.org>
- Date: Fri, 05 Mar 2010 09:05:21 +0100
- To: Andy Seaborne <andy.seaborne@talis.com>
- CC: SPARQL Working Group <public-rdf-dawg@w3.org>
Received on Friday, 5 March 2010 08:05:10 UTC
On 2010-3-4 15:47 , Andy Seaborne wrote: > > In > http://lists.w3.org/Archives/Public/public-rdf-dawg-comments/2010Feb/0012.html > > > Jeremy Carroll raises the issue of cycles. > > Given: > > eg:a eg:p eg:a > eg:a eg:p eg:b > > does "?a eg:p {3, 7} ?b" match ?b to both eg:a and eg:b by going round > the loop in eg:a ex:p eg:a a few times. > > One possibility is to allow this. I would agree with that. After all, looking at the data, I would expect SELECT ?x ?y WHERE {?x eg:p ?y.} does return ?x/eg:a ?y/ex:a as possible answer, doesn't it? If on the other hand, ?a eg:p {3, 7} ?b would not match ex:a for ?b that would be in contradiction... Ivan > > The other is to spec that this does not contribute to the length of the > path. A "simple path" in the graph theory terminology. > > http://en.wikipedia.org/wiki/Path_%28graph_theory%29 > > Andy > -- Ivan Herman, W3C Semantic Web Activity Lead Home: http://www.w3.org/People/Ivan/ mobile: +31-641044153 PGP Key: http://www.ivan-herman.net/pgpkey.html FOAF : http://www.ivan-herman.net/foaf.rdf vCard : http://www.ivan-herman.net/HermanIvan.vcf
Received on Friday, 5 March 2010 08:05:10 UTC