Optimizing Enterprise-Scale OWL 2 RL Reasoning in a Relational Database System

  • Vladimir Kolovski
  • Zhe Wu
  • George Eadon
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 6496)


OWL 2 RL was standardized as a less expressive but scalable subset of OWL 2 that allows a forward-chaining implementation. However, building an enterprise-scale forward-chaining based inference engine that can 1) take advantage of modern multi-core computer architectures, and 2) efficiently update inference for additions remains a challenge. In this paper, we present an OWL 2 RL inference engine implemented inside the Oracle database system, using novel techniques for parallel processing that can readily scale on multi-core machines and clusters. Additionally, we have added support for efficient incremental maintenance of the inferred graph after triple additions. Finally, to handle the increasing number of owl:sameAs relationships present in Semantic Web datasets, we have provided a hybrid in-memory/disk based approach to efficiently compute compact equivalence closures. We have done extensive testing to evaluate these new techniques; the test results demonstrate that our inference engine is capable of performing efficient inference over ontologies with billions of triples using a modest hardware configuration.


Semantic Model Inference Engine SPARQL Query Triple Pattern Query Answering 
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 2010

Authors and Affiliations

  • Vladimir Kolovski
    • 1
  • Zhe Wu
    • 2
  • George Eadon
    • 1
  1. 1.OracleNashuaUSA
  2. 2.OracleRedwood CityUSA

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