An Overview of Fuzzy Data Models

Abstract

Fuzzy databases provide means of representing, storing, and manipulating imprecise and uncertain information. This paper focuses on semantic and relational data models such as Chen’s entity-relationship model and Codd’s relational model and provides an overview of fuzzy extensions of these classical models that are generally incapable of dealing with imprecision, uncertainty, or partial knowledge. Primary attention is paid to the current state of fuzzy databases from the perspectives of conceptual modeling, data representation, database queries, and database design. This paper is considered as an update of the survey that appeared in JASIS (Kerre et al., 1986).Key wordsfuzzy entity-relationship modelsfuzzy relational data modelsfuzzy data representationfuzzy queriesfuzzy database design