- From: Pat Hayes <phayes@ihmc.us>
- Date: Tue, 10 Jan 2006 10:15:07 -0600
- To: Souripriya Das <souripriya.das@oracle.com>
- Cc: RDF Data Access Working Group <public-rdf-dawg@w3.org>, bparsia@isr.umd.edu, Enrico Franconi <franconi@inf.unibz.it>, Sergio Tessaris <tessaris@inf.unibz.it>
>Quoting from Pat Hayes's e-mail >http://lists.w3.org/Archives/Public/public-rdf-dawg/2006JanMar/0051.html >: > >"Another way to define S(Q) is to imagine that every bnode in Q is >replaced by a distinct query variable (which cannot be SELECTed, >however) and then use this definition. There are cases in which this >definition is slightly tighter than the previous one, eliminating >some redundancy. Also this doesn't need the ordered-merge idea." > >This seems to be a simpler way. Has this been discussed already? As I (dimly) recall, we did at one point consider not allowing bnodes in queries but this idea was rejected as too restrictive for the query writers (imagine taking some RDF and plopping variables where you want answers, but leaving the other bnodes alone, why not?) However, I think if we had realized the tar-pit we were getting into by allowing bnodes scoped to queries, we might have considered it more actively. It sure does make all the definitions easier (and I think conceptually clearer) if we assume that bnodes in queries are treated as simply a species of variable, as this neatly solves all the awkward 'scoping' problems that arise. Pat > >Thanks, >- Souri. > > >Attachment converted: betelguese2:souripriya.das.vcf (TEXT/Hdra) (00226A23) -- --------------------------------------------------------------------- IHMC (850)434 8903 or (650)494 3973 home 40 South Alcaniz St. (850)202 4416 office Pensacola (850)202 4440 fax FL 32502 (850)291 0667 cell phayesAT-SIGNihmc.us http://www.ihmc.us/users/phayes
Received on Tuesday, 10 January 2006 16:15:35 UTC