Re: OODBMS <-> RDF

Dear Ioannis,
Many thanks for this information. However, I am looking for studies on
the opposite direction: from an existing OO database to RDF. My main
concern here is how to specify the way mappings are done: a new
ontology? any existing one that I don't know of...? I suppose that the
problem of mappings does not apply to your case (at the OO<->RDF level,
I mean).

Best regards,

Pedro

Ioannis Athanasiadis escreveu:
> Dear Pedro,
>
> we have done some work towards a semantic-rich development 
> architecture [1]. Our goal was to utilize an OWL/RDF ontology as a 
> domain model to be used for software application development.  A 
> software tool for generating Enterprise Java Beans, Hibernate 
> mappings, and Relational schemas from an ontology is available online 
> [2].
> More documentation will be eventually available on [3]
>
> Best regards,
> Ioannis
>
> [1] Athanasiadis, I.N., Villa, F. & Rizzoli, A.E. (2007). Enabling 
> knowledge-based software engineering through 
> semantic-object-relational mappings. In 3rd Intl Workshop on Semantic 
> Web Enabled Software Engineering, 4th European Semantic Web 
> Conference, pp. 16-30 (online at: 
> http://swese2007.fzi.de/papers/04.Enabling_KB_SE.pdf)
> [2] http://imt.svn.sourceforge.net/svnroot/imt/Thinklab/
> [3] http://www.integratedmodelling.org
>
>
> On 30 Jan 2008, at 10:46, José Pedro Ferreira wrote:
>
>> 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/
>>>>
>>>>
>>>>
>>>>
>>
>> <jose_pedro_ferreira.vcf>
>
> -- 
> Dr Ioannis N. Athanasiadis
> IDSIA - Istituto Dalle Molle di Studi sull'Intelligenza Artificiale
> Galleria 2, CH-6928 Manno, Lugano, Switzerland
> tel: +41-586-666-671 fax: +41-586-666-661 mob: +41-798-141-680
> ioannis@idsia.ch - www.idsia.ch - www.athanasiadis.info