Normalization is a systematic process of ensuring that a relational database model is efficient, suitable for general-purpose querying and free of undesirable characteristics such as insertion, update, and deletion anomalies, leading to losing the integrity of the data. This normalization process also helps to eliminate data redundancy and reduces the chances of inconsistency after any insert, update, or delete operations.

For a better understanding, consider the following schema: Student (Name, Address, Subject, Grade)

There are a few problems or inefficiencies in this schema.

1) Redundancy: The student’s Address is repeated for each subject he is registered for.

2) Updating anomaly: We may have updated the Address in one tuple (row) while leaving it unchanged in the other rows. Thus we would not have a consistently unique address for each student.

3) Insertion Anomaly: We will not record a student’s Address without registering for at least one Subject. Similarly, when a student wants to enrol for a new Subject, it’s possible that a different Address to be inserted.

4) Deletion Anomaly: If a student decides to discontinue all the enrolled subjects, then the student’s address will also be lost in the process of deletion.

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