Alan’s blog

I just came across D2RQ, a notation (plus implementation) for mapping relational databases to RDF, developed over the last four years by Chris Bizer, Richard Cyganiak and others at Freie Universität Berlin. In a previous post, “digging ourselves back from the Semantic Web mire“, I worried about the ghetto-like nature of RDF and the need for “abstractions that make non-triple structures more like the Semantic Web”, D2RQ is exactly the sort of thing, allowing existing relational databases to be accessed (but not updated) as if they were and RDF triple stores, including full SPARQL queries.

As D2RQ has clearly been around for years, I tried to do a bit of a web search to find things the other way around – more programmer-friendly layers on top of RDF (or XML) allowing it to be manipulated with IDL-like or other abstractions closer to ‘normal’ programming. ECMAScript for XML (E4X) seems to be just this allowing reasonably easy access to XML (but I guess RDF would be ‘flat’ in this). E4X has been around a few years (standard since 2005), but as far as I can see not yet in IE (surprise!). I guess for really practical XML it would be JSON, and there’s a nice discussion of different RDF in JSON representation issues on the n² wiki “RDF JSON Brainstorming“. However, both E4X and RDF in JSON still are just accessing RDF nicely not adding higher level structure.

Going back to the beginning I was wondering about any tools that represent RDF as SQL / RDMS in order to make it available to ‘old technology’ … but then remembered that SPARQL creates tuples not triples so, I guess, one could say that is exactly what it does :-/

Nad did a brilliant guest lecture for our undergraduate HCI class at Lancaster on Monday. His slides and blog about the lecture are at Virtual Chaos. He touched on issues of democracy vs. authority of information, dynamic content vs. accessibility and of course increasing issues of privacy on social networking sites. He also had awesome slides to using loads of Flickr photos under creative commons … community content in action not just words! Of course also touched on Web3.0 and future convergence between emergent community phenomena and structured Semantic Web technologies.

Discussions on the Talis Platform Advisory Group prompted me to look at some of the APIs of new Semantic-Web-like services such as Freebase¹.

Freebase is interesting as its underlying representation is graph/relationship based like RDF, but its Metaweb Query Language (MQL) uses JSON which is a more programming-like whole and parts representation with arrays and slots. Facebook’s new Data Store API also has objects and associations, but does not use RDF or other obvious web technologies.

So the question is – if the closest things to Semantic Web apps on the internet don’t use SemWeb techology like RDF, SPARQL etc. … are these SemWeb techologies fit for purpose or indeed useful at all?

I think the answer is that (i) partly they are not fit for purpose – caught in a backwater by their history, but (ii) that is like all things and they are what we have got, and (iii) we can use some of the tools of computing to make them work …

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1. listen to Talis’ pod cast interview with Jamie Taylor Freebase’s ‘Minister of Information’ (sic). [back]