Q73.Marks: +2.0UGC NET Paper 2: Computer Sc 23rd August 2024 Shift 1
Fifth normal form is concerned with :
1.Join Dependency✓ Correct
2.Domain-Key
3.Multivalued dependency
4.Functional dependency
Solution
The correct answer is Join Dependency
Key Points
Join Dependency: A relation is in 5NF if it is in 4NF and all join dependencies in the relation are implied by the candidate keys. This means that if a relation can be decomposed into smaller relations and those relations can be joined to recreate the original relation without any loss of information, then the relation is in 5NF.
5NF specifically deals with cases where there are multiple independent multi-valued facts about the same entity that need to be split to eliminate redundancy.
Additional Information
Domain-Key: Refers to constraints based on domains and keys but is not specifically related to 5NF.
Multivalued Dependency: Concerned with the 4NF. A relation is in 4NF if it has no non-trivial multivalued dependencies.
Functional Dependency: Related to the definitions of 1NF, 2NF, and 3NF but does not directly address the concerns of 5NF.
