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Module 4: Understanding Normalization.

 

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Understanding Normalization


1. Define functional and transitive dependency?

Functional dependency: If the value of Y is determined by X then Y is functionally dependent on X. Y=X+1

Transitive dependency: When X determines Y and Y determines Z then Z is indirectly dependent on X that is transitive dependency.


2.What is normal form?

Normal forms are the steps contained within the process of Normalization such as 1NF, 2Nf, 3NF etc.


3. Write down the names of Normal forms 

There are Seven types of Normal forms such as

    i. 1st Normal form

    ii. 2nd Normal form

    iii. 3rd Normal form

    iv. Boyce-codd Normal form

    v. 4th Normal form

    vi. 5th Normal form

    vii. Domain key Normal form


4. Describe 1NF?

Eliminate repeating groups, such that all records in all tables can be identified uniquely, by a primary key in each table.


5. Describe 2NF?

The table must be in 1NF and All non-Key values must be fully functionally dependent on the primary key. No partial dependencies are allowed.


6. Describe 3NF?

The table must be in 2NF and eliminate transitive dependencies.








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