4NF

A relation is said to be in 4NF if it is in Boyce Codd Normal Form (BCNF) and has no multi-valued dependency

  • example:
    R(A,B,C,D) has A →> B and A →> C, then R should be decomposed into R1(A,B) and R2(A,C,D) to eliminate the multivalued dependency