RDF Query

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An RDF query is a question that you ask an RDF program that knows how to navigate RDF data.

See Also RDFQuery/Ideas

Implementations of RDF Query

Definitions

  • What is an RDF query?
  • How do you query a reified statement? (see RdfReification)
  • How do you represent BlankNodes in RDF queries?

Capabilities of QLs

  • Which RDF query languages can...
    • handle RDF schema-related queries?
    • do substring matches?
      • All that can do regex matching
  • do regex matching?
  • do recursive queries?
    • do template-matching queries?
    • do XSLT-like queries?
      • SPARQL's CONSTRUCT feature does a bit of that

How can queries be performed?

  • Is there a programmatic query API? (what is a programmatic query?)
  • How do I query generic RDBMS, SQL data using RDF query?
    • By dumping it to RDF (using e.g. D2R-Map) or by using a dynamic query translator like D2RQ (for Jena) or Federate.
  • How can I query and return provenance information in RDF query? (what is provenance information?)
    • Use a query language capable of querying sets of named graphs, e.g. SPARQL or TriQL
  • How do I represent RDF graphs in a (RDBMS, SQL) database and query them?
    • There's much existing work on this to be found out there.
  • Why not use an RDF graph with blanks for querying RDF? (See: GraphMatchingQuery)

Testing the Proposed Specification

We're starting to see demo services based on the SPARQL spec from the RDF Data Access WG: DawgShows.

  • RDFQueryTestCases
  • RDFQueryTestcasesRequirements
  • RdfQueryTestingBOF
  • RdfQueryTestingBudapestBOF
  • RdfQueryTestingBudapestMeeting
  • Are there any test suites or test cases for RDF query ?
    • As it is a proposal, these cannot be written yet. However, one can attempt to implement suggestions made about the specification and report back with your findings.
  • What summaries of RDF query are available?
  • Are there any product-independent query languages?
    • Are there any product-independent languages of any kind? Most likely it will be extended, even if a core is agreed. In light of that, one could say SQL. I suspect this is not the intended question.