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Re: [JSON] Elephant in the room

From: Sandro Hawke <sandro@w3.org>
Date: Wed, 23 Mar 2011 13:03:59 -0400
To: nathan@webr3.org
Cc: RDF WG <public-rdf-wg@w3.org>
Message-ID: <1300899839.3138.1554.camel@waldron>
On Wed, 2011-03-23 at 16:22 +0000, Nathan wrote:
> Just wanted to capture something I don't think I've conveyed until now:
> 
> Almost every developer I know, from enterprise to bedroom developers, 
> work primarily with OO oriented languages, or key/value data structures 
> in functional languages.
> 
> The primary *huge* issue here, is that most people can't work with 
> triples and graphs without special tooling. Not to mention that it's 
> highly unfamiliar to them.
> 
> Send an object with an id over the wire and people can use it, it's 
> familiar, they "get it", send them a triple, and they're lost - even if 
> they grok the graph and triple, they don't have the machinery to handle 
> it often.
> 
> This is pretty much the sole reason that every developer I know outside 
> of the sem web community does not use RDF in any way, even though they 
> like the concepts and would like "linked data".

Yes, good to name this elephant, even though I think we're already
working around it.

I think of this as a close cousin to the "object-relational impedance
mismatch"....

http://en.wikipedia.org/wiki/Object-relational_impedance_mismatch

... and sometimes I just call it that.   Many of the items listed on
that page don't apply, so many just "impedance mismatch" in the RDF
context is good enough.  I think I first heard that term applied to this
problem by Dave Reynolds.

My sense is that it manifests most clearly in RDF allowing a single
property of a single item can have multiple values at once.  That's
nonsense from an OO perspective.   (In RDF we can say the foaf:name
property of :Sandro has multiple values, simultaneously.  In OO, that's
nonsense, and instead we would have to say the foaf.name property of
Sandro has a value which is some sort of collection of other values.)

(As I recall, Dave Reynolds was also pointing out how different
rdfs:domain and rdfs:range and rdfs:subClassOf are from what OO folks
expect.)

This is part of why I like presenting SPARQL result sets to the json
folks.  There are no multiple values, and in general I think it's clear
to say that each object they get is a result from (or a match to) a
particular query.   They don't need to understand the query itself until
they are ready to understand the modeling, which is a more advanced step
that not everyone needs to take.

   -- Sandro
Received on Wednesday, 23 March 2011 17:04:11 GMT

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