When is a table in 2NF?

3 years ago
Database Management System

A table is in 2NF when it is in 1NF and it includes no partial dependencies. However, a table in 2NF may still have transitive dependencies, i.e., dependencies based on attributes that are not part of the primary key.

A table is in 2nd Normal Form (2NF) when it meets the following criteria:

  1. It is in 1st Normal Form (1NF)
  2. All non-primary key columns are fully dependent on the primary key. In other words, non-primary key columns cannot be functionally dependent on only a subset of the primary key.

A table in 2NF is considered to be free of partial dependencies.

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Bijay Satyal
Bijay Satyal
Oct 23, 2021
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