Tuple Relational Calculus for Paraconsistent Databases

  • Rajiv Bagai
Conference paper

DOI: 10.1007/3-540-44399-1_42

Volume 1952 of the book series Lecture Notes in Computer Science (LNCS)
Cite this paper as:
Bagai R. (2000) Tuple Relational Calculus for Paraconsistent Databases. In: Monard M.C., Sichman J.S. (eds) Advances in Artificial Intelligence. Lecture Notes in Computer Science, vol 1952. Springer, Berlin, Heidelberg

Abstract

A paraconsistent database is one in which information may be incomplete and/or inconsistent. A data model that does not attempt to eliminate such incompleteness or inconsistency, but rather is capable of functioning in their presence, has recently been developed. In this paper, we present a 4-valued tuple relational calculus for posing queries to paraconsistent databases based on that model. The syntax of our calculus is similar to that of the regular 2-valued relational calculus on ordinary relational databases, but our new 4-valued semantics makes it a useful querying tool for applications containing incomplete and inconsistent information. Moreover, as the model (out of necessity) freely permits infinite relations, the issue of safety of calculus expressions, that is so important in 2-valued systems, is not relevant any more.

Keywords

Relational data model Incomplete and inconsistent information Tuple relational calculus 

Preview

Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Copyright information

© Springer-Verlag Berlin Heidelberg 2000

Authors and Affiliations

  • Rajiv Bagai
    • 1
  1. 1.Department of Computer ScienceWichita State UniversityWichitaUSA