Normal Form

Question 1
In a relational data model, which one of the following statements is TRUE?
A
A relation with only two attributes is always in BCNF.
B
If all attributes of a relation are prime attributes, then the relation is in BCNF.
C
Every relation has at least one non-prime attribute.
D
BCNF decompositions preserve functional dependencies.
GATE CSE 2022   Database Management System
Question 2
Suppose the following functional dependencies hold on a relation U with attributes P, Q, R, S, \text{ and } T:

P \rightarrow QR \\ RS \rightarrow T

Which of the following functional dependencies can be inferred from the above functional dependencies?
[MSQ]
A
PS \rightarrow T
B
R \rightarrow T
C
P \rightarrow R
D
PS \rightarrow Q
GATE CSE 2021 SET-2   Database Management System
Question 3
If every non-key attribute functionally dependent on the primary key, then the relation will be in
A
First normal form
B
Second normal form
C
Third normal form
D
Fourth Normal form
ISRO CSE 2020   Database Management System
Question 4
Consider a relational table R that is in 3NF, but not in BCNF. Which one of the following statements is TRUE?
A
R has a nontrivial functional dependency X\rightarrow A, where X is not a superkey and A is a prime attribute.
B
R has a nontrivial functional dependency X\rightarrow A, where X is not a superkey and A is a non-prime attribute and X is not a proper subset of any key.
C
R has a nontrivial functional dependency X\rightarrow A, where X is not a superkey and A is a non-prime attribute and X is a proper subset of some key.
D
A cell in R holds a set instead of an atomic value.
GATE CSE 2020   Database Management System
Question 5
Let the set of functional dependencies F=\{QR\rightarrow S,R\rightarrow P,S\rightarrow Q\} hold on a relation schema X = (PQRS). X is not in BCNF. Suppose X is decomposed into two schemas Y and Z where Y = (PR) and Z = (QRS).
Consider the two statements given below:

I. Both Y and Z are in BCNF
II. Decomposition of X into Y and Z is dependency preserving and lossless.

Which of the above statements is/are correct?
A
Both I and II
B
I only
C
II only
D
Neither I nor II
GATE CSE 2019   Database Management System
Question 6
The set of attributes X will be fully functionally dependent on the set of attributes Y if the following conditions are satisfied.
A
X is functionally dependent on Y
B
X is not functionally dependent on any subset of Y
C
Both (A) and (B)
D
None of these
ISRO CSE 2018   Database Management System
Question 7
For a database relation R(a,b,c,d) where the domain of a,b,c and d include only atomic value, only the following functions dependencies and those that can be inferred from them hold
a\rightarrowc
b\rightarrowd
The relation is in:
A
First normal form but not in second normal form
B
Second normal form but not in third normal form
C
Third normal form
D
None of the above
ISRO CSE 2018   Database Management System
Question 8
Consider the following four relational schemas. For each schema, all non-trivial functional dependencies are listed. The underlined attributes are the respective primary keys.

Which one of the relational schemas above is in 3NF but not in BCNF?
A
Schema I
B
Schema II
C
Schema III
D
Schema IV
GATE CSE 2018   Database Management System
Question 9
The following functional dependencies hold true for the relational schema R{V,W,X,Y,Z}:
V \rightarrowW
VW \rightarrowX
Y\rightarrow VX
Y \rightarrowZ
Which of the following is irreducible equivalent for this set of functional dependencies ?
A
V \rightarrowW
V\rightarrowX
Y \rightarrowV
Y \rightarrowZ
B
V \rightarrowW
W \rightarrowX
Y\rightarrow V
Y\rightarrow Z
C
V \rightarrowW
V\rightarrow X
Y\rightarrow V
Y \rightarrowX
Y \rightarrowZ
D
V \rightarrowW
W\rightarrow X
Y\rightarrow V
Y \rightarrowX
Y \rightarrowZ
GATE CSE 2017 SET-1   Database Management System
Question 10
A database of resear charticles in a journal uses the following schema.

Which is the weakest normal form that the new database satisfies,but the old one does not?
A
1NF
B
2NF
C
3NF
D
BCNF
GATE CSE 2016 SET-1   Database Management System
There are 10 questions to complete.

9 thoughts on “Normal Form”

  3. In Question Number 34, there is printing mistake in ( A→→BC )
    The correct option is : i) if A→→B and A→→C then A→BC

    Reply

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