Axioms in Normalisation

Axioms :


1. Reflexive Property :

For any attribute X and Y

if Y is a proper subset of X, then X-> Y


2. Augumentive Propery :


For any attribute A,B,C,D

if A->B and C->D then

AC->BD

3. Transitive property :


For any attribute A,B,C

if A->B and B->C then

A->C


4. Union Property :


For any attribute A,B,C

if A->B and A->C then

A->BC

5. Decomposition Property :


For any attribute A,B,C

if  A->BC then

A->B and A->C


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