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Which of the following normal form(s) is/are based on the functional dependencies among the attributes of a relation? A. 1NF B. 2NF C. 3NF D. 4 NF

Which of the following normal form(s) is/are based on the functional dependencies among the attributes of a relation? A. 1NF B. 2NF C. 3NF D. 4 NF Correct Answer A, B and C

The correct answer is option 3.

Concept:

1 Normal forms, 2 Normal forms, 3 Normal forms, and Boyce Codd Normal Forms are based on the functional dependencies among the attributes of a relation.

First Normal forms:

  • There should be just one value in each table cell.
  • Every record must be distinct from the others.

Second Normal Forms:

  • It must be in 1NF.
  • Single Column Primary Key that does not functionally dependant on any subset of candidate key relation. It means it allows only fully functional dependency.

Third Normal Forms:

  • It must be in 2NF.
  • There are no transitive functional dependencies.

Boyce Codd normal form:

  • It must be in 3NF.
  • A table is in BCNF if every functional dependency X → Y, X is the super key of the table.

Fourth normal form:

  • It should be in the Boyce-Codd Normal Form.
  • The table should not have any Multi-valued Dependency.

Here 4 NF is not based on the functional dependencies among the attributes of a relation.

Hence the correct answer is A, B, and C.

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