Calì, Andrea and Gottlob, G. and Pieris, A. (2010) Query rewriting under non-guarded rules. Proceedings of the 4th Alberto Mendelzon International Workshop on Foundations of Data Management 619 , ISSN 1613-0073.
Abstract
We address the problem of answering conjunctive queries over knowledge bases, specified by sets of first-order sentences called tuple-generating dependencies (TGDs). This problem is highly relevant to query optimization, information integration, and ontological reasoning. We present a rewriting algorithm, inspired by resolution in Logic Programming, which is capable of dealing with an expressive class of TGDs, called sticky TGDs. Given a set of sticky TGDs and a conjunctive query, the algorithm produces a first-order query that can be then evaluated over the data, providing the correct answers. In this way, we establish that conjunctive query answering under sticky TGDs is in the highly tractable class ac0 in the data complexity.
Metadata
| Item Type: | Article |
|---|---|
| School: | Birkbeck Faculties and Schools > Faculty of Science > School of Computing and Mathematical Sciences |
| Research Centres and Institutes: | Birkbeck Knowledge Lab |
| Depositing User: | Sarah Hall |
| Date Deposited: | 09 May 2013 10:44 |
| Last Modified: | 09 Aug 2023 12:33 |
| URI: | https://eprints.bbk.ac.uk/id/eprint/6643 |
Statistics
Additional statistics are available via IRStats2.
Archive Staff Only (login required)
