Introduction to Normalization, Functional Dependency & Axioms Video Lecture | Question Bank for GATE Computer Science Engineering - Computer Science Engineering (CSE)

Normalization is a process in computer science engineering that involves organizing the data in a database to eliminate redundancy and dependency issues. It aims to ensure that each attribute in a table depends only on the key of the table, leading to a more efficient and organized database structure.

Functional dependency, in the context of computer science engineering, refers to the relationship between two sets of attributes in a database. It indicates that the value of one set of attributes determines the value of another set of attributes. It is an important concept in database design and helps ensure data integrity and consistency.

Normalization offers several benefits in computer science engineering, including: - Reducing data redundancy: By eliminating duplicate data, normalization helps conserve storage space and improves database efficiency. - Enhancing data integrity: Normalization ensures that data is consistent and accurate by minimizing update anomalies. - Simplifying data maintenance: A properly normalized database is easier to update and maintain as it follows a logical and organized structure. - Supporting scalability: Normalization allows for easier expansion and modification of the database schema without causing data inconsistencies. - Improving query performance: Well-normalized databases generally have faster query execution times due to their optimized structure.

There are several normal forms in normalization, each denoted by a specific number. The commonly recognized normal forms are: - First Normal Form (1NF): Ensures that each attribute in a table contains only atomic values and there are no repeating groups. - Second Normal Form (2NF): Builds upon 1NF and ensures that all non-key attributes are fully functionally dependent on the table's primary key. - Third Normal Form (3NF): Builds upon 2NF and ensures that there are no transitive dependencies between non-key attributes. - Boyce-Codd Normal Form (BCNF): A stricter version of 3NF that eliminates all non-trivial dependencies. - Fourth Normal Form (4NF): Addresses multi-valued dependencies and eliminates redundancy caused by them. - Fifth Normal Form (5NF): Handles join dependencies and further eliminates redundancy in complex database structures.

In functional dependency, axioms are a set of rules or properties that govern the behavior of functional dependencies. The commonly used axioms are: - Reflexivity: If Y is a subset of X, then X determines Y. - Augmentation: If X determines Y, then XZ determines YZ for any Z. - Transitivity: If X determines Y and Y determines Z, then X determines Z. - Union: If X determines Y and X determines Z, then X determines YZ. - Decomposition: If X determines YZ, then X determines Y and X determines Z.