- From: José Pedro Ferreira <jose.pedro.ferreira@cern.ch>
- Date: Wed, 30 Jan 2008 10:46:37 +0100
- To: <semantic-web@w3c.org>
- Message-ID: <47A0477D.1030106@cern.ch>
Dear all, Thank you so much for all the suggestions that you promptly provided! I'm currently taking a look at the extensive amount of information provided by Elisa and Niklas, and I see that there's already a lot of work in this area, though things are still a bit immature. Niklas, I'd really appreciate if you could provide me some information about this python structures <-> rdf transforms provided by oort, since I already have a layer that makes this kind of transformation in order to export JSON. So, maybe it will be useful. Thanks, once again, Cheers, Pedro Niklas Lindström escreveu: > Hi! > > This is *very* interesting. I am behind Oort [1] (which Jesse > mentioned). One of the ideas driving it is to have a mapping *both* > back and forth between object and RDF graphs. Since it's Python, there > may be some ground for what you're after. Specifically, Oort today > allows you to construct RDF from Python dict/list/atomic value > structures [2] (isomorphic to JSON, which you can load directly via > simplejson). If you can get these structures from the ZODB, I hope > Oort will take you to the RDF you need. > > A missing piece of the puzzle is generating mappers directly out of > OWL schemas (and possibly vice versa). But these mappers also > represent queries/aspects, which are more ragged and mixed, so this > merits more investigation. > > ... Going further and beyond... > > In a wider sense, the Oort ("Out Of RDF Transmogrifying") idea right > now is a tiny beginning of what I feel can be a promising way of > bridging the gap between RDF and current pragmatic ("less is more") > approaches that have emerged, such as microformats and JSON (along > with the nascent ideas of schemas for those, as proposed by James > Clark [3, 4] and e.g. the Mozilla team [5]). Much of what is discussed > regarding Atom extensions [6] also seem (to me) to point towards a > need for formalism "reduction" to fit more narrow contexts (by which I > mostly mean to reuse OWL ontologies in simpler scenarios, where I'm > afraid proper RDF continues to be "beyond the horizon"). > > I do think RDF is a "grand unifier" for modelling, but it seems that > for many specific contexts, it is viewed as "too formal" to get > traction. It's not impossible, but hard, to sell RDF as a perfect > match for smaller/local data syndication efforts. This poses the risk > of continued reinvention of many things RDF solves very well > (precision, I18N, data- and resource typing etc.). I believe that any > given context provides assumptions and locality (of terms etc) that > makes the decontextualized data which RDF is about *seem* superfluous. > But that next step is then always left unresolved, causing all these > integration problems that I assume many of us Semantic Web followers > see a solution for in RDF, OWL, SPARQL etc. > > Basically, I consider simpler representations to be wrapped in context > to reduce formal details, and I am convinced that that can be mapped > to the RDF data model rather unobtrusively. How is what I've only > begun scratching on the surface of.. > > I've wanted to get the time and energy to pitch this more formally, > but haven't gotten around to it much (more than with this message, and > a related blog post [7] last year). > > Where to go further then? I'd gladly invite you to join > <http://groups.google.com/group/oort>, which due to nigh zero activity > I'd happily recast from a python toolkit focus into the more general > vision I described above. Not the least since my scope has widened to > plans for e.g. a javascript version of the Oort mapper, as well as > examination of the Elmo [8] effort from the OpenRDF/Sesame people, > which looks very similar to this. Granted, I do not have the > experience yet to organize larger community efforts, so perhaps some > other form would work better? I'm happy to join any party interested > in this. > > (By analogy, this can be related to things as diverse as the relative > merits of dynamic, static and inferred typing in programming, ORMs for > RDBMSs, CouchDB-like technology, etc. Akin to "how to have the cake > and eat it too".. I believe we can do this. With insulated layers, > each simple and formal, as in many other cases.) > > Best regards, > Niklas > > [1] <http://oort.to/> > [2] <http://oort.to/oort_api/oort.test.test_rdfview-pysrc.html#test_from_dict> > [3] <http://blog.jclark.com/2007/04/do-we-need-new-kind-of-schema-language.html> > [4] <http://blog.jclark.com/2007/04/xml-and-json.html> > [5] <http://developer.mozilla.org/en/docs/Describing_microformats_in_JavaScript> > [6] <http://www.imc.org/atom-syntax/mail-archive/threads.html#20299> > [7] <http://dustfeed.blogspot.com/2007/01/knowledge-bits-and-pieces.html> > [8] <http://openrdf.org/doc/elmo/1.0-beta2/user-guide/> > > > > > On Jan 26, 2008 12:12 AM, Jesse Erdmann <jesse@jesseerdmann.com> wrote: > >> The only other D2R like software I'm aware of is Squirrel RDF, >> http://jena.sourceforge.net/SquirrelRDF/. I don't know of any support >> of ZODB. Is something like RDF Alchemy, >> http://www.openvest.com/trac/wiki/RDFAlchemy, or Oort, >> http://oort.to/, similar to what you're looking for? >> >> 2008/1/25 José Pedro Ferreira <jose.pedro.ferreira@cern.ch>: >> >> >>> Hello. >>> Yes, I know that RDF can be seen as object-oriented. But... I'm not >>> considering if it is possible to display OO data using RDF, but rather >>> how to make this translation in a smooth, fairly automatic way, without >>> having to write enormous amounts of replicated code, and taking >>> advantages of the similarities that exist between the two models. It's a >>> matter of "translation techniques". >>> >>> Cheers, >>> >>> Pedro >>> >>> cdr escreveu: >>> >>> >>>> On Fri Jan 25, 2008 at 02:34:28PM +0100, Jos? Pedro Ferreira wrote: >>>> >>>> >>>>> Hello. >>>>> I need to make data stored in an object-oriented (ZODB) database available >>>>> as RDF. I've been looking for existing architectures and mapping >>>>> techniques, and eventually found D2RQ >>>>> <http://www4.wiwiss.fu-berlin.de/bizer/D2RQ/spec/>. The problem is that >>>>> D2RQ seems too much oriented towards the relational paradigm. >>>>> Is there any research done on this particular area? I've been thinking >>>>> about something similar to D2RQ, but object-oriented. However, I'd like to >>>>> know if there's any work already done about this subject. >>>>> >>>>> >>>> your OOobject is your RDFsubject, your OOobject property is your RDFpredicate, and your OOobject property's value(s) is/are your RDFobject(s) (mind the nameclash) >>>> >>>> your OOobject have URI fields, of course. >>>> >>>> this also works with JSON.. which can be thought of as an OOobject serialization, and compatible with RDF so long as your property-symbols are URIs and each JSONobject has a URI property >>>> >>>> >>>> theyre pretty much identical. even RDFs with its subclassing and subtyping is an OO model.. replace 'object' with 'resource' in the literature >>>> >>>> >>>> >>>> >>>>> Thanks in advance, >>>>> >>>>> Pedro >>>>> >>>>> >>>> >>>>> begin:vcard >>>>> fn:Jose Pedro Ferreira >>>>> n:Ferreira;Jose Pedro >>>>> org:CERN;IT-UDS-AVC >>>>> adr:;;;Geneva;;;Switzerland >>>>> email;internet:jose.pedro.ferreira@cern.ch >>>>> title:Software Developer >>>>> tel;work:+41 22 76 75025 >>>>> tel;cell:+41 763 045 795 >>>>> x-mozilla-html:FALSE >>>>> url:http://www.zarquon.biz >>>>> version:2.1 >>>>> end:vcard >>>>> >>>>> >>>>> >>>> >>>> >>> >> >> -- >> Jesse Erdmann >> jesse@jesseerdmann.com >> Twitter: http://twitter.com/jesseerdmann >> Blog: http://blog.jesseerdmann.com/ >> >> >> >>
Received on Wednesday, 30 January 2008 09:46:55 UTC