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arXiv · 2205.02190

Ontology-Mediated Querying on Databases of Bounded Cliquewidth

Carsten Lutz·Leif Sabellek·Lukas Schulze
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Abstract

We study the evaluation of ontology-mediated queries (OMQs) on databases of bounded cliquewidth from the viewpoint of parameterized complexity theory. As the ontology language, we consider the description logics $\mathcal{ALC}$ and $\mathcal{ALCI}$ as well as the guarded two-variable fragment GF$_2$ of first-order logic. Queries are atomic queries (AQs), conjunctive queries (CQs), and unions of CQs. All studied OMQ problems are fixed-parameter linear (FPL) when the parameter is the size of the OMQ plus the cliquewidth. Our main contribution is a detailed analysis of the dependence of the running time on the parameter, exhibiting several interesting effects.

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Carsten Lutz, Leif Sabellek, Lukas Schulze. 2022-05-04. Ontology-Mediated Querying on Databases of Bounded Cliquewidth. https://doi.org/10.24963/kr.2022%2F25

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