As with my first "FOAF tale", "Joe Triple" yesterday's story "Bee Node" was intended as more than an exercise in punning. The original story was intended to help illustrate a few aspects of Semantic Web technology which I think I worth drawing attention to. But this time around the focus is mainly on SPARQL rather … Continue reading Bee Node Deconstructed →

Detective Piotr Sparql lent back in his chair cradling a tumbler of vodka and reflected on his most recent case. It had started as a simple missing person; he'd been assigned to investigate the disappearance of Beatrice "Bee" Node: @prefix foaf: <http://xmlns.com/foaf/0.1&gt; . </person/bnode> a foaf:Person; foaf:name "Beatrice Node"; foaf:nick "Bee" foaf:mbox <mailto:bnode@example.com>. His investigation … Continue reading Bee Node: A FOAF Tale →

I hate quoting myself, as I worry about it making me seem like a pompous ass, but I feel moved to do it in this instance after reading Danny's posting about DataPortability Service Discovery, in which he discusses the current blueprint from the DataPortability group. Danny rightly points out that FOAF already provides a means … Continue reading Self-Description for Service Connection →

Nearly three years ago now I announced a little GUI tool , called Twinkle for working with SPARQL queries. Since then a number of nice people have asked whether I'm going to update the tool to add various features, like support for querying persistent data, inferencing, etc. And Danny pointed out that the UI wasn't … Continue reading Twinkle 2.0 →

I'm sure that the majority of you realised that yesterdays posting, Joe Triple: A FOAF Tale was more than just a bit of whimsy. The story is intended as an illustration of a few semantic web principles. In this post I wanted to review those principles in a clearer way, although I can't promise to … Continue reading Joe Triple: Deconstructed →

Once upon a time there was a Resource whose name was Joe Triple: @prefix foaf: <http://xmlns.com/foaf/0.1&gt; . </joe> foaf:name "Joe Triple". Joe was a lonely Thing, and resolved to set off into the world to learn more about himself. On this quest for self discovery Joe learnt that his birthday was 29th November 2007: @prefix … Continue reading Joe Triple: A FOAF Tale →

Data integration is easy with Semantic Web technologies, right? We've all said it, but has anyone actually sat down and tried to elucidate the ways in which technologies like RDF and OWL actually help with data integration? I don't ever remember seeing one so here's a first attempt. Each of the sections below tries to … Continue reading How Shall I Integrate Thee? Let Me Count the Ways… →

I often find it useful to try on different metaphors for application design and architecture. The stock set of patterns that are used in a particular domain are always very useful for communicating the design and intent of a complex application, but I find that experimenting with different approaches is a useful exercise that often … Continue reading Streams, Pools and Reservoirs →

I hadn't seen anyone blog this yet, but Andy Seaborne has released ARQ 2.0. Looks like Andy has been doing some internal restructuring on the code but the most interesting new feature is initial support for a draft SPARQL Update language. And earlier today Vinaya Shastrakar posted to jena-dev to announce some custom extensions to … Continue reading ARQ Updates →

Section 10.3.2 of RFC2616 describes the HTTP status code 301 Moved Permanently. The first paragraph explains that the status code means that: The requested resource has been assigned a new permanent URI and any future references to this resource SHOULD use one of the returned URIs. Clients with link editing capabilities ought to automatically re-link … Continue reading The Semantics of 301 Moved Permanently →