Define first normal form and second normal form, Database Management System

First Normal Form and second normal form

First Normal Form (1NF)

A relation is said to be in 1NF if it having no non-atomic values and each row can give a unique combination of values.

Second Normal Form (2NF)

A relation is said to be in 2NF f if it is already in 1NF and each attribute fully depends on the primary key of the relation. Speaking inversely, if a table has some attributes which is not dependant on the primary key of that table, and then it is not in 2NF.

 

Posted Date: 7/26/2013 6:37:55 AM | Location : United States







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