1NF,2NF, 3NF Normalization

If you want to know more about normalization and keys refer this posts:

http://vinayjallipalli75996.blogspot.in/2016/12/different-type-of-keys-in-database.html

http://vinayjallipalli75996.blogspot.in/2016/12/normalization-in-database.html





1NF : Composite attribute are not allowed.

2NF: All non prime attributes are fully functional dependent with primary key.that is non prime attributes should not be partially dependent on primary key.

3NF: There should not be any dependency between non prime attributes.
             
Example For 3NF (see the below fig.): student id,name, dob , street,city, zip,state->>>
                       1)sid,name,dob
                       2)zip, city, state, Street becoz zip is dependent on rest of the three.



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