Query Answering in the Description Logic Horn-\(\mathcal{SHIQ}\)

  • Thomas Eiter
  • Georg Gottlob
  • Magdalena Ortiz
  • Mantas Šimkus
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5293)


We provide an ExpTime algorithm for answering conjunctive queries (CQs) in Horn-\(\mathcal{SHIQ}\), a Horn fragment of the well-known Description Logic \(\mathcal{SHIQ}\) underlying the OWL-Lite standard. The algorithm employs a domino system for model representation, which is constructed via a worst-case optimal tableau algorithm for Horn-\(\mathcal{SHIQ}\); the queries are answered by reasoning over the domino system. Our algorithm not only shows that CQ answering in Horn-\(\mathcal{SHIQ}\) is not harder than satisfiability testing, but also that it is polynomial in data complexity, making Horn-\(\mathcal{SHIQ}\) an attractive expressive Description Logic.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • Thomas Eiter
    • 1
  • Georg Gottlob
    • 2
  • Magdalena Ortiz
    • 1
  • Mantas Šimkus
    • 1
  1. 1.Institute of Information SystemsTU ViennaAustria
  2. 2.Computing LaboratoryOxford UniversityUnited Kingdom

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