Abstract
We present cq-programs, which enhance nonmonotonic description logics (dl-) programs by conjunctive queries (CQ) and union of conjunctive queries (UCQ) over Description Logics knowledge bases, as well as disjunctive rules. dl-programs had been proposed as a powerful formalism for integrating nonmonotonic logic programming and DL-engines on a clear semantic basis. The new cq-programs have two advantages: First, they offer increased expressivity by allowing general (U)CQs in the body. And second, this combination of rules and ontologies gives rise to strategies for optimizing calls to the DL-reasoner, by exploiting (U)CQ facilities of the DL-reasoner. To this end, we discuss some equivalences which can be exploited for program rewriting. Experimental results for a cq-program prototype show that this can lead to significant performance improvements.

URL:
http://rewerse.net/publications/rewerse-publications.html#REWERSE-RP-2007-142

BibTeX:

@inproceedings{REWERSE-RP-2007-142,
	author = {Thomas Eiter and Giovambattista Ianni and Thomas Krennwallner and Roman Schindlauer},
	title = {Exploiting Conjunctive Queries in Description Logic Programs},
	booktitle = {Proceedings of 20th International Workshop on Description Logics, Brixen-Bressanone, Italy (8th--10th June 2007)},
	year = {2007},
	volume = {250},
	pages = {259--266},
	url = {http://rewerse.net/publications/rewerse-publications.html#REWERSE-RP-2007-142}
}