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What is Normalization, First Normal Form, Second

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What is Normalization, First Normal Form, Second Normal Form , Third Normal Form?

1.Normalization is process for assigning attributes to entities–Reducesdata redundancies–Helps eliminate data anomalies–Produces controlledredundancies to link tables

2.Normalization is the analysis offunctional dependency between attributes / data items of userviews?It reduces a complex user view to a set of small andstable subgroups of fields / relations

1NF:Repeating groups must beeliminated, Dependencies can be identified, All key attributesdefined,No repeating groups in table

2NF: The Table is already in1NF,Includes no partial dependencies–No attribute dependent on a portionof primary key, Still possible to exhibit transitivedependency,Attributes may be functionally dependent on non-keyattributes

3NF: The Table is already in 2NF, Contains no transitivedependencies

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