Conjunctive Query Inseparability of OWL 2 QL TBoxes
نویسندگان
چکیده
The OWL2 profile OWL2QL, based on the DL-Lite family of description logics, is emerging as a major language for developing new ontologies and approximating the existing ones. Its main application is ontology-based data access, where ontologies are used to provide background knowledge for answering queries over data. We investigate the corresponding notion of query inseparability (or equivalence) for OWL2QL ontologies and show that deciding query inseparability is PSPACE-hard and in EXPTIME. We give polynomial time (incomplete) algorithms and demonstrate by experiments that they can be used for practical module extraction.
منابع مشابه
Conjunctive Query Inseparability in OWL 2 QL is ExpTime-hard
We settle an open question on the complexity of the following problem: given two OWL 2 QL TBoxes and a signature, decide whether these TBoxes return the same answers to any conjunctive query over any data formulated in the given signature. It has been known that the complexity of this problem is between PSpace and ExpTime. Here we show that the problem is ExpTime-complete and, in fact, deciding...
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تاریخ انتشار 2011