Fuzzy data dependencies and implication of fuzzy data dependencies

In this paper, we give the definitions of fuzzy functional dependency (FFD), fuzzy multivalued dependency (FMVD) and fuzzy join dependency (FJD). We show that the inference rules of FFDs and FMVDs, which are similar to Armstrong's Axioms for classical case, are sound and complete. Furthermore, we show that a classical data dependency satisfies the definition of a fuzzy data dependency. We also show that FFD can be viewed as an FMVD and an FMVD can be viewed as an FJD. We discuss the test for implication of fuzzy data dependencies. A series of results, which are similar to the classical result, is obtained in this paper. (C) 1997 Elsevier Science B.V.