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arXiv · 1604.05258

Theoretically Optimal Datalog Rewritings for OWL 2 QL Ontology-Mediated Queries

Meghyn Bienvenu·Stanislav Kikot·Roman Kontchakov·Vladimir V. Podolskii·Michael Zakharyaschev
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Abstract

We show that, for OWL 2 QL ontology-mediated queries with (i) ontologies of bounded depth and conjunctive queries of bounded treewidth, (ii) ontologies of bounded depth and bounded-leaf tree-shaped conjunctive queries, and (iii) arbitrary ontologies and bounded-leaf tree-shaped conjunctive queries, one can construct and evaluate nonrecursive datalog rewritings by, respectively, LOGCFL, NL and LOGCFL algorithms, which matches the optimal combined complexity.

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Meghyn Bienvenu, Stanislav Kikot, Roman Kontchakov, Vladimir V. Podolskii, Michael Zakharyaschev. 2016-04-18. Theoretically Optimal Datalog Rewritings for OWL 2 QL Ontology-Mediated Queries. https://arxiv.org/abs/1604.05258

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