Database-Management-System
August 29, 2024Database-Management-System
August 29, 2024UGC NET CS 2017 Nov- paper-3
| Question 9 |
If every non-key attribute is functionally dependent on the primary key, then the relation is in __________ .
| First normal form | |
| Second normal form | |
| Third normal form | |
| Fourth normal form |
Question 9 Explanation:
1NF : A relation is in 1NF if it does not contain multi-value attributes and composite attributes.
2NF: A relation is in 2NF is there is no partial dependency exist in the relation. i.e.
primary_key → non-key attribute
prime_attribute → non-key attribute.
3NF : A relation is in 3NF if there is no transitive dependency or we can say that a relation is in 3NF if either LHS of a functional dependency is a super key or the RHS of the functional dependency is a prime key attribute.
4NF : A relation is in 4NF if there is no multivalued dependency exist in the relation.
Hence the correct answer is option (C)
NOTE: A prime key attribute is a attribute which is the part of primary key attributes. For example: If ABC is the the primary key then A,B,C, AB, AC, BC are the prime key attributes.
2NF: A relation is in 2NF is there is no partial dependency exist in the relation. i.e.
primary_key → non-key attribute
prime_attribute → non-key attribute.
3NF : A relation is in 3NF if there is no transitive dependency or we can say that a relation is in 3NF if either LHS of a functional dependency is a super key or the RHS of the functional dependency is a prime key attribute.
4NF : A relation is in 4NF if there is no multivalued dependency exist in the relation.
Hence the correct answer is option (C)
NOTE: A prime key attribute is a attribute which is the part of primary key attributes. For example: If ABC is the the primary key then A,B,C, AB, AC, BC are the prime key attributes.
Correct Answer: C
Question 9 Explanation:
1NF : A relation is in 1NF if it does not contain multi-value attributes and composite attributes.
2NF: A relation is in 2NF is there is no partial dependency exist in the relation. i.e.
primary_key → non-key attribute
prime_attribute → non-key attribute.
3NF : A relation is in 3NF if there is no transitive dependency or we can say that a relation is in 3NF if either LHS of a functional dependency is a super key or the RHS of the functional dependency is a prime key attribute.
4NF : A relation is in 4NF if there is no multivalued dependency exist in the relation.
Hence the correct answer is option (C)
NOTE: A prime key attribute is a attribute which is the part of primary key attributes. For example: If ABC is the the primary key then A,B,C, AB, AC, BC are the prime key attributes.
2NF: A relation is in 2NF is there is no partial dependency exist in the relation. i.e.
primary_key → non-key attribute
prime_attribute → non-key attribute.
3NF : A relation is in 3NF if there is no transitive dependency or we can say that a relation is in 3NF if either LHS of a functional dependency is a super key or the RHS of the functional dependency is a prime key attribute.
4NF : A relation is in 4NF if there is no multivalued dependency exist in the relation.
Hence the correct answer is option (C)
NOTE: A prime key attribute is a attribute which is the part of primary key attributes. For example: If ABC is the the primary key then A,B,C, AB, AC, BC are the prime key attributes.
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