Chapter 1. Jumping Right In: Some Data and Some Queries
Chapter 2 provides some background on RDF, the semantic web, and where SPARQL fits in, but before going into that, let’s start with a bit of hands-on experience writing and running SPARQL queries to keep the background part from looking too theoretical.
But first, what is SPARQL? The name is a recursive acronym for SPARQL Protocol and RDF Query Language, which is described by a set of specifications from the W3C.
Note
The W3C, or World Wide Web Consortium, is the same standards body responsible for HTML, XML, and CSS.
As you can tell from the “RQL” part of its name, SPARQL is designed to query RDF, but you’re not limited to querying data stored in one of the RDF formats. Commercial and open source utilities are available to treat relational data, XML, JSON, spreadsheets, and other formats as RDF so that you can issue SPARQL queries against data in these formats—or against combinations of these sources, which is one of the most powerful aspects of the SPARQL/RDF combination.
The “Protocol” part of SPARQL’s name refers to the rules for how a client program and a SPARQL processing server exchange SPARQL queries and results. These rules are specified in a separate document from the query specification document and are mostly an issue for SPARQL processor developers. You can go far with the query language without worrying about the protocol, so this book doesn’t go into any detail about it.
The Data to Query
Chapter 2 describes more about ...