Third normal form

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Third normal form (3NF) is a property of a relational model, specifically tables that is a criterion of database normalization.

The first criterion of being third normal form is that the table be second normal form.

Within a table that is in third normal form, the data in each column in each row are dependent only on columns that are part of the primary key. A primary key is one or more columns in a row that is used to identify and index that row of the table. Columns that are not related to any column in the primary key are removed.