Hi, I just found an old thread [1] that mentions another solution - append an underscore to property URIs that otherwise cannot be serialized as RDF/XML.
I think DBpedia should do that for the few URIs that cause problems, but not too many, e.g. http://dbpedia.org/property/2ndregionalCupApps shouldn't be changed. See "I18n of Semantic Web Applications" [2] by Auer et al for a thorough investigation. Christopher [1] http://lists.w3.org/Archives/Public/semantic-web/2009Nov/thread.html#msg116 [2] http://data.semanticweb.org/conference/iswc/2010/paper/385/html On Feb 28, 2012 6:20 PM, "Jona Christopher Sahnwaldt" <[email protected]> wrote: > > Hi, > > all of these errors stem from the problem that not all > RDF triples can be represented in RDF/XML. [1] > (IMHO, a shortcoming in the RDF/XML spec that could > easily have been fixed by introducing something like > <rdf:Property rdf:URI="http://some/uri_(can't_be_xml)">, > similar to <rdf:Description rdf:about="http://some/uri";>.) > > As Jeen Broekstra wrote on dbpedia-discussion in August 2011 [2]: > > "The only reliable way around the problem is to use a serialization > format that does cope with all legal RDF properly, such as N-Triples or > Turtle." > > But still, when someone really wants RDF/XML, what > should Virtuoso do with triples that can't be serialized? > > In some cases, there actually is a possible representation. > For example, the property URI > http://dbpedia.org/property/2ndregionalCupApps > could be represented as > <p:ndregionalCupApps xmlns:p="http://dbpedia.org/property/2";> > Weird and confusing for humans, no problem for computers. > > In those cases that can't be represented in RDF/XML, > the spec says 'throw a "this graph cannot be serialized > in RDF/XML" exception or error' [1]. Probably not a good > solution for us. I think Virtuoso should omit such triples > from RDF/XML, but include something like a comment > in their place that they were omitted and are available in > other formats (like NTriples). > > Regards, > Christopher > > [1] http://www.w3.org/TR/REC-rdf-syntax/#section-Serialising > [2] > http://sourceforge.net/mailarchive/forum.php?thread_name=4E443EE5.9020309%40gmail.com&forum_name=dbpedia-discussion > > > > On Sun, Feb 26, 2012 at 21:02, Axel Polleres <[email protected]> wrote: > > Hi all, > > > > FWIW, I had posted a similar post/bug-report (also reporting invalid XML on > > DBPedia) on the pedantic-web list a while ago: > > https://groups.google.com/group/pedantic-web/browse_thread/thread/651ed89bd18e189a# > > > > best, > > Axel > > > > On 26 Feb 2012, at 12:19, Andreas Harth wrote: > > > >> Hi Juergen, > >> > >> On 02/24/12 15:14, Juergen Umbrich wrote: > >> > i tried to query some live DBPedia documents but do not succeed since > >> > the retrieved content is not valid RDF/XML. > >> > >> I can confirm that: > >> > >> $ rapper -c "http://dbpedia.org/resource/French_Guiana"; > >> rapper: Parsing URI http://dbpedia.org/resource/French_Guiana with > >> parser rdfxml > >> rapper: Error - URI /data/French_Guiana.xml:158 - Using property element > >> 'Description' without a namespace is forbidden. > >> rapper: Error - URI http://dbpedia.org/resource/French_Guiana - > >> Resolving URI failed: Failed writing body (0 != 1188) > >> rapper: Failed to parse URI http://dbpedia.org/resource/French_Guiana > >> rdfxml content > >> > >> I've also seen unescaped &'s in DBpedia. > >> > >> I've cc'ed [email protected] to notify the > >> DBpedia guys. > >> > >> Best regards, > >> Andreas. > >> > >> PS. there's been several issues mentioned lately, e.g. Axel's mail > >> from 2012-01-04, or my mail from 2011-08-09 on [email protected]. > >> > > ------------------------------------------------------------------------------ Keep Your Developer Skills Current with LearnDevNow! The most comprehensive online learning library for Microsoft developers is just $99.99! Visual Studio, SharePoint, SQL - plus HTML5, CSS3, MVC3, Metro Style Apps, more. Free future releases when you subscribe now! http://p.sf.net/sfu/learndevnow-d2d _______________________________________________ Dbpedia-discussion mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/dbpedia-discussion
