Data dependencies in fuzzy object oriented databases model based on hedge algebra

Abstract

The single most important concept in database schemas design is that of a fijnctional dependency. A functional dependency describes the relationship among attributes and is one of the key concepts used in the normalization. On the basic of fuzzy object-oriented databases model with hedge algebra has been proposed, in this paper, we introduce the study of the form of data dependencies, including fuzzy functional dependency in object class, fully fiizzy functional dependency, partial fuzzy functional dependency, transitive fuzzy functional dependency and fuzzy functional dependency with quantifier in natural languages. Based on the concepts of fuzzy functional dependencies, the paper also propose the normal form of fuzzy object-class in the model.