Explain why 4NF is a normal form more desirable than BCNF.
1: Describe 1NF, 2NF, 3NF.
2: Explain why 4NF is a normal form more desirable than BCNF.
Do you need high quality Custom Essay Writing Services?
Normalization is the process of organizing the attributes and relations of a relationaldatabase to minimize data redundancy. 4NF or Fourth Normal Form is a level ofdatabase normalization in which there are non-trivial multivalued dependencies otherthan a candidate key. 4NF builds on 1NF, 2NF, 3NF and the Boyce-Codd Normal Form(BCNF). BCNF is considered as a stronger version of the 3NF. However, splitting therelation schema in BCNF will result in losing all functional dependency. This is why 4NF ispreferred over BCNF since its decomposition preserves all functional dependencies andreduces the repetition of information.2: Describe 1NF, 2NF, and 3NF:There are specific rules to be followed when normalizing a database. Normalization rulesare divided into the following normal forms:1NF: According to First Normal Form, any two rows of data should not contain repetitivegroup of information. Each column must have a unique value so that multiple columnscannot be used to return the same row. The table should be organized into rows andeach row should have a primary key, which identifies it as unique. Each row must nothave a column in which there is more than one value and the data must be separated into multiple rows. When following 1NF, the data redundancy increases since there will bemultiple columns with the same data in multiple rows. However, each row will be uniqueas a whole.Example:Student Table per 1NF:StudentAgeSubjectKevin16MathematicsKevin16ChemistryKelley15Biology2NF:According Second Normal Form, any column should not be partially dependent onthe primary key. It means that when a table has concatenated primary key, each columnin the table that is not part of the primary key must depend entirely upon theconcatenated key in order to exist. For example, consider the table in the 1NF example. In this table, the candidate key isStudent and Subject. However, Age column depends only on Student column. To makethis table comply with 2NF, the Subject column must be split out into an independenttable and paired up with Student names as foreign key. So the tables would look like this: