![]() In the above example, using with the 3NF, there is no redundancy of data while inserting the new records.The advantage of removing transitive dependency is, it reduces the amount of data dependencies and achieves the data integrity.So, we need to move the city and state to the new table, with Zip as a Primary key. The dependency between Zip and other fields is called Transitive Dependency.In the above table, EId is a primary key but City, State depends upon Zip code.3NF reduces the duplication of data and also achieves the data integrity.While using the 2NF table, there should not be any transitive partial dependency.Third Normal Form (3NF) is used to minimize the transitive redundancy.Now, the above tables comply with the Second Normal Form (2NF).This violates the rule for 2NF as the rule says 'No non-prime attribute is dependent on the proper subset of any candidate key of the table'.ĢNF (Second Normal Form) : Employee1 Table However, it is not in 2NF because non prime attribute Employee_Age is dependent on ECode alone, which is a proper subset of candidate key. An attribute which is not part of candidate key is known as non-prime attribute.The main rule of 2NF is, 'No non-prime attribute is dependent on the proper subset of any candidate key of the table.'. ![]() It contains atomic values because the table cannot hold multiple values.Each set of column must have a unique value.In 1NF, there should not be any repeating group of data.It simplifies each attribute in a relation.First Normal Form (1NF) is a simple form of Normalization.Types of Normalization Following are the types of Normalization:ħ. It eliminates the undesirable characteristics like Insertion, Updation and Deletion Anomalies.It ensures data dependencies make sense that means data is logically stored.It is a formal process of developing data structures.Normalization avoids the data redundancy.It is the technique of building database structures to store data.ĭefinition of Normalization“Normalization is a process of designing a consistent database by minimizing redundancy and ensuring data integrity through decomposition which is lossless.” Features of Normalization. ![]()
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