Practical RDF

Chapter 10. Querying RDF: RDF as Data

RDF as a model for metadata and RDF/XML as a way of serializing the model are interesting, but the power of the specifications lies in our ability to access the data easily, using techniques we’re familiar with from other data models, such as the relational data model discussed in Chapter 6.

It is only natural that techniques used for one data model should be adapted for use with another; so the method for accessing the relational data model, Structured Query Language (SQL), is used in a similar manner with RDF/XML through language techniques such as SquishQL, RDQL, RQL, and others.

Tip

Many of the query languages and schemas mentioned in this chapter are also covered in an online document at http://www.w3.org/2001/11/13-RDF-Query-Rules. In addition, if your interest is more inclined to RDF as data (or to the more logical side of RDF), check out the www-rdf-rules discussion list at http://lists.w3.org/Archives/Public/www-rdf-rules/.

RDF and the Relational Data Model

RDF and the relational data model are both metadata models, so it’s natural to want to see how the one can work with the other. Stanford took a look at different designs of tables for storing RDF data in an online paper located at http://www-db.stanford.edu/~melnik/rdf/db.html. With some differences based on data types and the ability to store multiple models, most of the schemas demonstrated were basically the same—store the model as triples, with or without support for additional ...