Computer Sciene of Udayana State University

April 26, 2009

General Definitions of 2NF and 3NF

Filed under: Computer Science — ignaga @ 2:03 AM
  • Based on candidate keys (not only primary keys)
  • Second normal form (2NF)

A relation that is in 1NF and every non-prime attribute is fully functionally dependent on any candidate key.

  • Third normal form (3NF)

A relation that is in 1NF and 2NF and in which no non-prime attribute is transitively dependent on any candidate key.

  • These definitions may find hidden redundancies.

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