Andy Seaborne of HP Labs, Bristol, has announced a "preview release" of a query language for the Jena RDF API.

Derived from Libby Miller's work on SquishQL, RDQL treats RDF as data and provides query with triple patterns and constraints over a single RDF model. Seaborne notes that RDQL is targetted at scripting use and for experimenttion in information modeling languages.

His examples include:

All the triples in the model:

        SELECT *
        WHERE (?x, ?y, ?z)

The contents of bags:

        SELECT ?b, ?y
        WHERE  (?b, <rs:type>, <rs:Bag>), (?b, ?x, ?y)
        AND    ! ( ?x eq <rs:type> && ?y eq <rs:Bag> )
        USING  rs FOR <http://www.w3.org/1999/02/22-rdf-syntax-ns#>

Java JAR files, Javadoc and examples can be found from the RDQL web page.