session 4 LNMIIT

If every non-key attribute is functionally dependent on the primary key, then the relation will be in ?

• First Normal Form

• Second Normal Form

• Third Normal Form

• No Normal Form

Which of the following set of independencies is suitable for making a relation R(ABCD) to be in 3NF but not in BCNF

• {AB→CD, A→C, D→B}

• {AB→CD, C→DA}

• {A→BCD, B→CD, C→D}

• {AB→CD, C→A, D→B}

Suppose a relation R is in 3NF. Then an FD: X→A is not valid on R, if

1 X is a proper subset of some key

2 X is not a proper subset of any key

3 X is a key

4 A is a part of some key

• 1 and 2 are correct

• 1 and 3 are correct

• 3 and 4 are correct

• None is correct

The reliability of a system with n redundant components each having a reliability of r is

• 1-(1-r)^n

• 1+(1-r)^n

• 1-(1+r)^n

• (1+r)^n

Choose the incorrect statement

• A relation in 2NF must also be in 1NF

• A relation in 3NF must also be in 2NF

• A relation in 3NF must also be in BCNF

• A relation in BCNF must also be in 3NF

In database de-normalization is used for

• Database backup

• Deleting tables in normal form

• Eliminating redundancy

• Performance tuning

A primary index refers to

• primary key to relation

• Foreign key of relation

• Search key of on which relation is sorted

• Degree of B+ tree

Atomicity of domains of attributes is related to

• First Normal Form

• Second Normal Form

• Third Normal Form

• Boyce Codd Normal Form

Which of the following statement is correct ?

• Data redundancy can be handled by inconsistency

• Redundancy in data may lead to its inconsistency

• Inconsistency in data may lead to Redundancy

• Data inconsistency can be handled by redundancy

If every non-key attribute is functionally dependent on the primary key, then the relation will be in

• First Normal Form

• Third Normal Form

• Second Normal Form

• None of the above