An Extension of Classical Functional Dependency: Rough Functional Dependency and its Inference Rules

摘要

Relational database model has constituted an incontestable success in database history. In this context, a lot of research has been paid to functional dependencies due to their importance in the design of relational database. In this paper, rough functional dependency is discussed. Firstly we give the formal definitions for antecedent upper or lower redundant factor and consequent upper or lower redundant factor based on rough functional dependency, then the properties of rough functional dependency and its inference rules are explored.