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arXiv · 1804.07274

A Practical Acyclicity Notion for Query Answering over Horn-SRIQ Ontologies

David Carral·Cristina Feier·Pascal Hitzler
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Abstract

Conjunctive query answering over expressive Horn Description Logic ontologies is a relevant and challenging problem which, in some cases, can be addressed by application of the chase algorithm. In this paper, we define a novel acyclicity notion which provides a sufficient condition for termination of the restricted chase over Horn-SRIQ TBoxes. We show that this notion generalizes most of the existing acyclicity conditions (both theoretically and empirically). Furthermore, this new acyclicity notion gives rise to a very efficient reasoning procedure. We provide evidence for this by providing a materialization based reasoner for acyclic ontologies which outperforms other state-of-the-art systems.

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David Carral, Cristina Feier, Pascal Hitzler. 2018-04-19. A Practical Acyclicity Notion for Query Answering over Horn-SRIQ Ontologies. https://doi.org/10.1007/978-3-319-46523-4_5

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