There has been recently an increasing number of people dropping on IRC (#tracker on GimpNet), with nice ideas for projects using Tracker. Some of them are looking for using Tracker on a server, or accessing it using languages other than C or Vala, which are usecases we don’t really support right now (although our DBus interface is of course language agnostic, it is not really the preferred IPC), and some others are just curious about the idea of having a global metadata database.
The common factor in all those users, is that at some point they start playing with SPARQL (Tracker being an RDF database, SPARQL is the query language to access the data). And, inevitably, they ask us where they can find documentation… The problem is, there is of course documentation on the W3C website about SPARQL, but many users find it hard to follow. Personally, the only section I use in the W3C doc is the SPARQL grammar reference. However, we also have various SPARQL examples in the Tracker documentation on Gnome Live, and a page explaining the non-standard SPARQL features supported by Tracker. Those two pages are usually enough to get people started, and allow them to write their first queries.
I initially intended this article to be about how to write fast SPARQL queries, but I will split that part in another post, to keep the size reasonable.
And remember, Tracker will be part of Gnome 3.0, so it’s now the best moment to learn about it! The project is evolving at a tremendous pace, every weekly release being loaded with fixes and performance improvements. If you still have memories about Tracker 0.6, be sure to erase them carefully, and take a fresh look at Tracker 0.9!