[Zope3-dev] Vocabularies, sources and relationships

[Michel Pelletier]

> Message: 7
> Date: Thu, 7 Apr 2005 14:12:06 +0200
> From: Florent Guillaume <fg at nuxeo.com>
> Subject: Re: [Zope3-dev] Vocabularies, sources and relationships
> To: gintas at pov.lt
> Cc: Santi Camps <scamps at earcon.com>, zope3-dev at zope.org
> Message-ID: <20050407121206.GA5111 at flo.in.nuxeo.com>
> Content-Type: text/plain; charset=us-ascii
>
> Gintautas Miliauskas  <gintas at pov.lt> wrote:
> > There is an easy-to-use relationship library included in SchoolBell
> > (http://www.schooltool.org/schoolbell).  It is independent from other
> > packages in SchoolBell.  You can get a feel of managing relationships
> > between objects using this package by looking through its README:
> > http://source.schooltool.org/viewcvs/trunk/schoolbell/src/schoolbell/rela
> >tionship/README.txt?rev=3153&view=markup
>
> How does this relate to a tool like zemantic? Could zemantic be used as
> a backend storage for the relationships manipulated by the library?

Interesting coincidence, I was just talking yesterday with Ben Saller about 
SchoolTool and this very subject vis a vis Zemantic.

I tend to think of relational models as generally equivalent (and there is 
probably some proof somewhere that they are).   Whether you speak RDF 
(subject, predicate, object), or something like AT refs (referer, reference, 
referent), or a more traditional RDBMS (row, property, cell) you are talking 
about the same underlying theory.

I haven't looked at the ST library much, I get the impressions it's more 
focused on similar uses to that of Archetype references, which is great.  
There are features in AT refs that would be a bit clumsy to implement in 
Zemantic (like relationships being persistent objects with behavior and data) 
although not at all impossible.

Clumsy unless you need your relationships to span systems and applications.  
The your relationship model must be based on something like RDF or its 
equivalent (something that does not apply application specifc interpretation 
to the stored references).  The other upshot of using something like RDF is 
that you are not inventing a whole relational model that does not necessiarly 
play natively with others.  

-Michel

>
> Florent
>
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> Florent Guillaume, Nuxeo (Paris, France)   CTO, Director of R&D
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