Hello! I did some digging and discovered that the test will work (using latest trunk, 1236 right now) if you change DAWG_DATASET_COMPLIANCE in "rdflib/sparql/Algebra.py" to False. Not sure wether or not this signifies a much bigger problem, my example code below does it by "monkey patch" (and I will not change this in the file for now, I feel it may be a more deep problem).
This is the "test" code I used. (Please notice my use of FILTER - I'm not sure wether that is needed in SPARQL or if the spec says that SPARQL does no such "no uniqueness assumption" for bindings by default.) ----------------- 8< ------------------- from rdflib import ConjunctiveGraph as CG, Namespace from rdflib.sparql import Algebra Algebra.DAWG_DATASET_COMPLIANCE = False data = """ @prefix foaf: <http://xmlns.com/foaf/0.1/> . @prefix : <tag:example.org,2007;stuff/> . :a foaf:knows :b . :a foaf:knows :c . :a foaf:knows :d . :b foaf:knows :a . :b foaf:knows :c . :c foaf:knows :a . """ q = """ PREFIX foaf: <http://xmlns.com/foaf/0.1/> select distinct ?person where { ?person foaf:knows ?a . ?person foaf:knows ?b . filter (?a != ?b) . } """ g = CG() from StringIO import StringIO g.parse(StringIO(data), format='n3') print g.query(q).serialize('json') ----------------- >8 ------------------- (Also, the JSON serialization chops "p" off of "person". It was introduced by a change in Variable.py at revision 1166, but it looks reasonable to fix "sparql/QueryResult.py" instead (which compensates for the old way with a bunch of reasonably obsolete "[1:]" chopping). I will probably do that in a while.) Best regards, Niklas On 8/6/07, whit <[EMAIL PROTECTED]> wrote: > ok... makes me feel a little less nuts. will create a test case. > > -w > > On 8/6/07, Drew Perttula <[EMAIL PROTECTED] > wrote: > > whit wrote: > > > I'm trying to do a match like so: > > > > > > select distinct ?person > > > where { > > > ?person foaf:knows ?a . > > > ?person foaf:knows ?b . > > > } > > > > > > in plain terms, I want all people who know both ?a and ?b . My query > > > work if I include just a single pattern (ala ?person foaf:knows ?a or > > > ?person foaf:knows ?b) but fails if both pattern are present despite > > > triples representing persons knowing ?a and ?b. > > > > Looks right to me (assuming you bound ?a and ?b). Does it behave > > differently without 'distinct'? I recommend writing this into a test > > case if you can. Then we'll all have exactly the same code to run, and > > we can put it in the suite so it gets run on every future version of > rdflib. > > > > > > -- > > | david "whit" morriss > | > | contact :: http://public.xdi.org/=whit > > "If you don't know where you are, > you don't know anything at all" > > Dr. Edgar Spencer, Ph.D., 1995 > > > "I like to write code like > other ppl like to tune their > cars or 10kW hifi equipment..." > > Christian Heimes, 2004 > > _______________________________________________ > Dev mailing list > Dev@rdflib.net > http://rdflib.net/mailman/listinfo/dev > > _______________________________________________ Dev mailing list Dev@rdflib.net http://rdflib.net/mailman/listinfo/dev
