What is 3NF?

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3NF stands for Third Normal Form. A database is called in 3NF if it satisfies the following conditions:

  • It is in second normal form.
  • There is no transitive functional dependency.
    For example: X->Z
    Where:
    X->Y
    Y does not -> X
    Y->Z so, X->Z

3NF stands for Third Normal Form, which is a normalization technique used in database design to reduce redundancy and improve data integrity. In 3NF:

  1. The table must be in 2NF (Second Normal Form).
  2. All non-prime attributes (attributes not part of any candidate key) must be dependent on the primary key.

In simpler terms, a table is in 3NF if:

  • It is already in 2NF.
  • There are no transitive dependencies, meaning no non-prime attribute depends on another non-prime attribute.