Flexible querying of relational databases: Fuzzy set based approach

Abstract

This paper presents a flexible fuzzy-based approach for querying relational databases. Although, many fuzzy query approaches have been proposed, there is a need for a more flexible, simple and human-like query approach. Most of previously proposed fuzzy query approaches have a disadvantage that they interpret any fuzzy query statement into a crisp query statement then evaluate the resulted tuples to compute their matching degrees to the fuzzy query. The main objective of the proposed fuzzy query approach of this paper is to overcome the above disadvantage by evaluating each tuple directly through the use of stored database objects namely packages, procedures and functions. Consequently, the response time of executing a fuzzy query statement will be reduced. This proposed approach makes it easy to use fuzzy linguistic values in all clauses of a select statement. The added value of this proposed approach is to accelerate the execution of fuzzy query statements.