Independence Under Incomplete Information

TL;DR

This paper explores how independence concepts can be effectively represented in relational databases with incomplete information, introducing possible and certain independence, and analyzing their implications and computational complexities.

Contribution

It proposes new independence concepts for incomplete information in relational databases and analyzes their axiomatisability and computational complexity.

Findings

Established results on axiomatisability of independence concepts

Analyzed computational complexity of implication problems

Presented data and combined complexity results for model checking

Abstract

We initiate an investigation how the fundamental concept of independence can be represented effectively in the presence of incomplete information in relational databases. The concepts of possible and certain independence are proposed, and first results regarding the axiomatisability and computational complexity of implication problems associated with these concepts are established. In addition, several results for the data and the combined complexity of model checking are presented. The findings help reduce computational overheads associated with the processing of updates and answering of queries.