Disjunctive Rules and Null Values: Logic Programs with Incomplete Information

Abstract

The introduction of negation in rule bodies of logic programs may lead to semantic ambiguities: Normal programs can have more than one stable model and the three-valued well-founded model may leave the truth status of some ground atoms undetermined. We show that this kind of ambiguity can be naturally combined with ambiguities caused by incomplete information. We define generalized notions of stable and well-founded models which allow to combine recursion, negation and incomplete information within a uniform framework. The well-founded approximation is composed of two not necessarily identical anti-monotonic operators. A general characterization of the best well-founded approximation is given.

Programs with disjunctions, maybe tuples and null values are studied as examples of logic programs with incomplete information. What concerns null values, our approach can also be seen as a generalization of Biskup’s proposal for relational databases.

Conference

Publication date: September 1996

Publication date (Print): September 1996

Pages: 1-18

Affiliations

Institute of Computer Science III, University of Bonn

Römerstr. 164, 53117 Bonn, Germany

Article

DOI: 10.14236/ewic/ADBIS1996.12

Copyright statement: © Jürgen Kalinski. Published by BCS Learning and Development Ltd. Proceedings of the International Workshop on Advances in Databases and Information Systems (ADBIS ‘96). Moscow

License:

This work is licensed under a Creative Commons Attribution 4.0 Unported License. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/

Conference name: Proceedings of the International Workshop on Advances in Databases and Information Systems (ADBIS ‘96)

Conference acronym: ADBIS

Conference number:

Conference location: Moscow

Conference date: 10-13 September 1996

Conference sponsor: Electronic Workshops in Computing (eWiC)

Conference theme: Advances in Databases and Information Systems

Product

Product Information: 1477-9358BCS Learning & Development

Self URI (article page): https://www.scienceopen.com/hosted-document?doi=10.14236/ewic/ADBIS1996.12

Self URI (journal page): https://ewic.bcs.org/

Categories

Series title: Electronic Workshops in Computing