Normalization is a database design technique which organizes tables in a manner that reduces redundancy and dependency of data. It divides larger tables into smaller tables and links them using relationships.

First

Second

Third

Fourth

Be in Second Normal Form (2NF)

Be in Third Normal Form (3NF)

Have a single attribute key

Have a composite key

Eliminate all hidden dependencies

Eliminate the possibility of a insertion anomalies

Have a composite key

Have all non key fields depend on the whole primary key

BCNF is stricter than 3 NF

Lossless, dependency -preserving decomposition into 3 NF is always possible

Loss less, dependency – preserving decomposition into BCNF is always possible

Any relation with two attributes is BCNF

Key

Key revisited

Superset key

None of the mentioned

Functional dependency

Database modeling

Normalization

Decomposition

1NF

2NF

3NF

All of the mentioned

For any pincode, there is only one city and state. Also, for given street, city and state, there is just one pincode. In normalization terms, empdt1 is a relation in

1 NF only

2 NF and hence also in 1 NF

3NF and hence also in 2NF and 1NF

BCNF and hence also in 3NF, 2NF and 1NF

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