- From: Eric Prud'hommeaux <eric@w3.org>
- Date: Tue, 19 Sep 2006 12:27:55 +0200
- To: Bijan Parsia <bparsia@cs.man.ac.uk>
- Cc: Kendall Clark <kendall@monkeyfist.com>, Ivan Herman <ivan@w3.org>, "Ralph R. Swick" <swick@w3.org>, Dan Connolly <connolly@w3.org>, RDF Data Access Working Group <public-rdf-dawg@w3.org>, Sandro Hawke <sandro@w3.org>
On Tue, Sep 19, 2006 at 08:35:31AM +0100, Bijan Parsia wrote: > On Sep 19, 2006, at 8:06 AM, Eric Prud'hommeaux wrote: > > >After going through the wordings with Ivan, Ralph, DanC and Sandro, > >we came up with some new wording that are hopefully precise without > >requiring too much context. > > I cc your coauthors so they can respond directly. > > >On Sun, Sep 17, 2006 at 06:53:05PM -0400, Kendall Clark wrote: > >> > >> > >>On Sep 12, 2006, at 7:26 AM, Bijan Parsia wrote: > >> > >>> > >>>http://www.w3.org/2001/sw/DataAccess/rq23/rq24.html > >>> > >>>I would prefer that: > >>> Should DISTINCT be based on lean graphs? > >>>Be phrased as > >>> What is the definition of DISTINCT? > >> > >>I agree with this suggestion to the editors. > > > >"Should the keyword DISTINCT recognize logically equivilant graphs?" > > All the forms of distinct, except term-distinct, "recognize" (give > the same answers to up to isomorphism) logically equivalent graphs. > Now, it is true that I underemphasized term-distinctness (though I > believe Andy's post mentioned it), but the choice isn't between term- > distinct and (some other form), but between term-distinct, and source- > lean distinct, and answer-lean distinct. > > So I think it's imprecise and actutally requires far more context > than the simple "What is the definition" variants. > > >>> Should SPARQL care about graphs that are inconsistent by D- > >>>entailment? > >>> > >>>as: > >>> What are the answers of a query of a D-inconsistent graph? > >> > >>And with this one too. > > > >We preferred Kendall's wording > >"What are the answers to a contradictory KB?" > > Yes that's fine. > > >though I am not sure the world will comprehend the interaction between > >entailment and contradictory KBs... > > They don't need to. > > >>>Finally, I would prefer a different phrasing for: > >>> """Many of these issues reduce to "Is SPARQL a graph query > >>>language or a higher level query language?" """" > >> > >>I *really* dislike this current phrasing; it's far too tendentious to > >>be useful. What is a "higher level query language" anyway? > >> > >>>But without specifying which issues do so and how, I think it's > >>>more confusing than helpful. > >> > >>Agreed. > > > >We put a lot of thought into this one and arrived at > >[[ > >Many of these issues revolve around, "Should SPARQL be sensitive to > >only the graph structure (per the 1st last call semantics) > > I object to the parenthetical. For example, DISTINCT is independent > to a large degree to the underlying BGP semantics. Furthermore, > DISTINCT was *unspecified*, that is, it didn't have a settled > semantics in the 1st last call. > > So, I'm not sure that "many" of these issues revolve around that. > > I would raise it as a distinct issue thought. But it's not like > settling "Query RDF syntax or semantics" will *settle* everything. It > will be suggestive and directive, of course. > > [snip] > >Given this, I removed this issue as well, yielding > >[[ > >Pending issues: > > > > * Should SELECTed variables be separated by commas? > > > > * Should the keyword DISTINCT recognize logically equivilant > > graphs? > > As above, I object. > > > * Should SPARQL care about graphs that are inconsistent by > > D-entailment? > > "Care about?" Obviously, on any approach, it "*cares*" about them. > How about: > What are the answers of a query against an inconsistent KB? > > (A la Kendall?) Note: I forgot to transplant this one from the meeting: "What should SPARQL return if a graph is inconsistent by virtue of use of the above datatypes?" > > * Should blank nodes be treated differently than variables in the > > query pattern? > > > >Many of these issues revolve around, "Should SPARQL be sensitive to > >only the graph structure (per the 1st last call semantics) or the > >semantics of RDF graphs as well." The working group could use guidance > >from the community on this point. > > See above. Kill the parens, and I would prefer "graph structure" be > replaced with the more transparent "syntax". > > Cheers, > Bijan. -- -eric home-office: +1.617.395.1213 (usually 900-2300 CET) +33.1.45.35.62.14 cell: +33.6.73.84.87.26 (eric@w3.org) Feel free to forward this message to any list for any purpose other than email address distribution.
Received on Tuesday, 19 September 2006 10:26:53 UTC