First normalization (1 NF)



Normalization : 

Boyce codd introduced a number of normaliztions.  It is a multi-step process that puts data into tabular form by removing duplicated data from the relation tables.

Two purposes :

              1. Eliminating useless data &
                2. Make sure data is logically stored.

Normalization rules :

              1. First normalization (1 NF)
              2. Second normalization (2 NF)
              3. Third normalization (3 NF) &
               4. Boyce code normal form (BCNF).

Description :


=> First normalization (1 NF) : 

             It is a property of a relation in a relational database.
             Conditions : 
                       a) Each set of column must have an unique value.
                        

 
                    b) Each table should be organized into rows and
                    c) Each row should have a primary key.
 
Example :
Lets consider below table :
 
 
Now we are going to make this table in 1NF form.
 
 
Advantages : 
            a) In 1NF.
 
Disadvantages : 
           a) Need more than one table.
            b) Redundancy is still there.

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