Richard, > is that URLs containing '&' lead to broken (non-well-formed) RDF/XML. Only if the XML serializer is broken - '&' must be encoded, that's standard practice in XML. There was a problem in Virtuoso, but that has been fixed: http://sourceforge.net/mailarchive/message.php?msg_id=28876318
In other words: changing DBpedia URIs is not the right way to fix a broken XML serializer. :-) Christopher On Tue, Mar 6, 2012 at 09:22, Richard Light <rich...@light.demon.co.uk> wrote: > Christopher, > > I don't have strong views about the details of URI encoding. (In my view, > both Wikipedia and dbpedia should use simple numeric identifiers for each > concept, rather than these stupid and mutable made-up-from-the-page-title > ones. But that's maybe a separate thread.) > > However, I think I need to point out that the reason I started this thread > is that URLs containing '&' lead to broken (non-well-formed) RDF/XML. So I > think that '%26' is mandatory, whatever happens to other characters. > > Richard > > > On 06/03/2012 00:14, Jona Christopher Sahnwaldt wrote: > > Dear all, > > I just checked a few specs to figure out what would be the best policy > for DBpedia regarding URI encoding. > > In summary, I think DBpedia should encode as few characters as > possible, e.g. use '&', not '%26'. > > The URI spec [1] has a lot of special cases, but in the end it's quite > clear that in our case we do not HAVE to encode most special > characters like '&'. See 3.3 Path Component. > > More importantly, the RDF spec includes the following note [2]: > > Because of the risk of confusion between RDF URI references that would > be equivalent if derefenced, the use of %-escaped characters in RDF > URI references is strongly discouraged. > > Could hardly be clearer... > > > A related, but different issue is how Wikipedia and Virtuoso dereference > URIs. > > Wikipedia is very lenient: "&_(EP)" [3] is equivalent to > "%26_%28EP%29" [4]. Even "OS%2F2" [5] is treated as equivalent to > "OS/2" [6]. (Not sure which of these bahaviors is or isn't violating > the URI spec). > > Virtuoso on dbpedia.org is very strict: it only returns data for > "OS/2" [7] and "&_%28EP%29" [8], but empty pages for all other > encoding variants. > > > Christopher > > [1] http://www.ietf.org/rfc/rfc2396.txt > [2] http://www.w3.org/TR/rdf-concepts/#dfn-URI-reference > [3] http://en.wikipedia.org/wiki/&_(EP) > [4] http://en.wikipedia.org/wiki/%26_%28EP%29 > [5] http://en.wikipedia.org/wiki/OS%2F2 > [6] http://en.wikipedia.org/wiki/OS/2 > [7] http://dbpedia.org/resource/OS/2 > [8] http://dbpedia.org/resource/&_%28EP%29 > > > On Tue, Feb 21, 2012 at 15:04, Jimmy O'Regan <jore...@gmail.com> wrote: > > On 21 February 2012 13:47, Richard Light <rich...@light.demon.co.uk> wrote: > > Jimmy, > > Not, I'm not confused. :-) > > Fair enough. > > I just thought that if the "&" were URLencoded it wouldn't need to be XML > escaped, because as you say it would then read "%26", and so wouldn't cause > problems to the XML parser. And I thought URLencoding should happen here. > To quote a random Web source [1]: > > That the URL isn't XML escaped in RDF/XML is clearly and unambiguously > a bug; that it isn't URL escaped is more a matter for discussion, but > the general consensus will probably be 'do what Wikipedia do', which > is to not escape ampersands. > > -- > <Sefam> Are any of the mentors around? > <jimregan> yes, they're the ones trolling you > > ------------------------------------------------------------------------------ > 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 > Dbpedia-discussion@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/dbpedia-discussion > > ------------------------------------------------------------------------------ > 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 > Dbpedia-discussion@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/dbpedia-discussion > > > -- > Richard Light > > ------------------------------------------------------------------------------ > 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 > Dbpedia-discussion@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/dbpedia-discussion > ------------------------------------------------------------------------------ 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 Dbpedia-discussion@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/dbpedia-discussion
