Functional Dependency - Irreducible Function Depending Set

Irreducible Function Depending Set

A functional depending set S is irreducible if the set has the following three properties:

  1. Each right set of a functional dependency of S contains only one attribute.
  2. Each left set of a functional dependency of S is irreducible. It means that reducing any one attribute from left set will change the content of S (S will lose some information).
  3. Reducing any functional dependency will change the content of S.

Sets of Functional Dependencies(FD) with these properties are also called canonical or minimal.

Read more about this topic:  Functional Dependency

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