# Dichotomies in Ontology-Mediated Querying with the Guarded Fragment

@article{Hernich2017DichotomiesIO,
title={Dichotomies in Ontology-Mediated Querying with the Guarded Fragment},
author={Andr{\'e} Hernich and Carsten Lutz and Fabio Papacchini and Frank Wolter},
journal={Proceedings of the 36th ACM SIGMOD-SIGACT-SIGAI Symposium on Principles of Database Systems},
year={2017}
}
• Published 9 May 2017
• Computer Science
• Proceedings of the 36th ACM SIGMOD-SIGACT-SIGAI Symposium on Principles of Database Systems
We study the complexity of ontology-mediated querying when ontologies are formulated in the guarded fragment of first-order logic (GF). Our general aim is to classify the data complexity on the level of ontologies where query evaluation w.r.t. an ontology O is considered to be in PTime if all (unions of conjunctive) queries can be evaluated in PTime w.r.t. O and coNP-hard if at least one query is coNP-hard w.r.t. O. We identify several large and relevant fragments of GF that enjoy a dichotomy…
23 Citations

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