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.


Data Complexity Description Logic Conjunctive Query Query Answering Standard Reasoning 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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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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