That fact that RDF expresses everything using the same simple three-part data structure has usually been a great strength, but in the case of ordered lists (or RDF collections) it’s pretty messy. The specification defines a LISP-like way of using triples to identify, for each position in a list, what the first member is and what list has the rest of them after that. When saying “and here are the rest” for every member of the list, you don’t want to have to come up with a…

The recent publication of RDF 1.1 specifications fifteen years and three days after RDF 1.0 became a Recommendation has not added many new features to RDF, although it has made a few new syntaxes official, and there were no new documents about the SPARQL query language. The new Recommendations did clean up a few odds and ends, and one bit of cleanup officially removes an annoying impediment to straightforward querying of strings.

Ubuntu has a utility called Tracker that makes it easy to search your hard disk, a bit like the old Google Desktop with a few extra features. One extra feature ranks among the coolest SPARQL applications I’ve ever seen: the ability to execute SPARQL queries against data extracted from files on your hard disk.

In the typical classification of NoSQL databases, the “graph” category is one that was not covered in the “NoSQL Databases for RDF: An Empirical Evaluation” paper that I described in my last blog entry. (Several were “column-oriented” databases, which I always thought sounded like triple stores—the “table” part of they way people describe these always sounded to me like a stretched metaphor designed to appeal to relational database developers.) A…