- From: Seaborne, Andy <andy.seaborne@hp.com>
- Date: Wed, 23 Mar 2005 16:58:05 +0000
- To: kendall@monkeyfist.com
- CC: DAWG Mailing List <public-rdf-dawg@w3.org>
Kendall Clark wrote: > On Wed, Mar 23, 2005 at 03:55:55PM +0000, Seaborne, Andy wrote: > > >>pattern-group. >> >> { pattern } UNION {} >> >>is "pattern OR true". > > > Ah, hmm. I think an example query like that should be in > rq23. FWIW. I'll tweak my stuff, though. Would you care to suggest one? Go on - make my day - send data, query and results. > > >>>> | element dataset-constraint { >>>> (uri | variable), (group-pattern) >>>> }* >>>> ^^^^ ????? why * >>> >>> >>>I assume trang set that cardinality to * because of sparqlx-23.xml in >>>the zip file, which serializes this query: >> >>I'd do that as a group with two GRAPHs in it rather than special casing it. > > > But that wouldn't change the cardinality of dataset-constraint, would > it? You'd still have something like: > > <query-pattern> > <group-pattern> > <dataset-constraint> > <uri>...</uri> > <triple-pattern>...</triple-pattern> > </dataset-constraint> > <dataset-constraint> > <variable name="foo"/> > <triple-pattern></triple-pattern> > </dataset-constraint> > </group-pattern> > </query-pattern> > > Plus, I don't understand this as an interpretation of rq23 syntax: > > GRAPH data:aliceFOAF { ...several triple patterns... } > > Doesn't the { and } introduce a group-pattern? > > Kendall Anything can be repeated - GRAPH isn't different. UNION, OPTIONALS, constriants, other groups. It should be that groups patterns take some single thing element In the rq23 grammer, rephrased group-pattern := pattern-element* pattern-element := triples | optional | union | graph | constraint but you would want to not introduce an extra tag for pattern-element so something like: group-pattern := (triples | optional | union | graph | group-pattern | constraint )* element query-pattern { (group-pattern | element pattern-group { triple-pattern* } | element optional-group { pattern-group } | element dataset-constraint { (uri | variable), group-pattern } | element union { group-pattern* } | element constraint { ... } | element group-pattern )* ^^^^^^ star here } Andy
Received on Wednesday, 23 March 2005 16:58:57 UTC