What are the various forms of normalisation?

Question

Accepted Answer

Normalization is a process of organizing data in a database to eliminate redundancy and improve data integrity.

First Normal Form (1NF) - Eliminate duplicate data by separating them into multiple tables.
Second Normal Form (2NF) - Remove partial dependencies by creating separate tables for sets of attributes.
Third Normal Form (3NF) - Eliminate transitive dependencies by creating separate tables for related attributes.
Boyce-Codd Normal Form (BCNF) - Remove anomalies by ensuring that every determinant is a candidate key.
Fourth Normal Form (4NF) - Eliminate multi-valued dependencies by creating separate tables for related attributes.
Fifth Normal Form (5NF) - Remove join dependencies by decomposing tables into smaller ones.

Accepted Answer

They are:- 1NF, 2NF, 3NF, BCNF, 4NF, 5NF, 6NF being first, second, third, Boyce-Codd, fourth, fifth, sixth normal form respectively.

Top Cognizant Full Stack Software Developer interview questions & answers