GATE CSE

Database Management System

Functional Dependencies and Normalization

Previous Years Questions

## Marks 1

In a relational data model, which one of the following statements is TRUE?

Consider a relation R(A, B, C, D, E) with the following three functional dependencies.
AB $$\to$$ C ; BC $$\to$$ D ; C $$\to$$ E;
The number of superk...

A database of research articles in a journal uses the following schema.
(VOLUME, NUMBER, STARTPAGE, ENDPAGE, TITLE, YEAR, PRICE)
The primary key is (V...

Consider the relation $$X\left( {P,Q,R,S,T,U} \right)$$ with the following set of functional dependencies
$$\eqalign{
& F = \left\{ \, \right....

The maximum number of superkeys for the relation schema $$R(E, F, G, H)$$ with $$E$$ as key is ______.

A prime attribute of a relation scheme $$R$$ is an attribute that appears

Consider the relation schema $$R = \left( {E,\,F,\,G,\,H,\,I,\,J,\,K,L,\,M,\,N} \right)$$ and the set of functional dependencies $$\left\{ {\left\{ {E...

Which of the following is TRUE?

Which one of the following statements about normal forms is FALSE?

A table has fields, $$F1, F2, F3, F4, F5,$$ with the following functional dependencies:
$$F1 \to F3.\,F2 \to F4.\,\,\,\left( {F1\,.\,F2} \right) \to ...

Relation $$R$$ with an associated set of functional dependencies, $$F,$$ is decomposed into $$BCNF.$$ The redundancy (arising out of functional depend...

Consider a schema $$R(A,B,C,D)$$ and functional dependencies $$A \to B\,\,$$ and $$C \to D\,\,$$. Then the decomposition of $$R$$ into $${R_1}\left( {...

Let $$R=(A,B,C,D,E,F)$$ be a relation scheme with the following dependencies: $$C \to F,\,E \to A,\,EC \to D,\,A \to B.$$ Which of the following is a ...

Which normal form is considered adequate for normal relational database design?

State True or False with reason. There is always a decomposition into Boyce-codd normal form $$(BCNF)$$ that is lossless and dependency preserving.

## Marks 2

Consider the relation R(P, Q, S, T, X, Y, Z, W) with the following functional dependencies.
PQ → X; P → YX; Q → Y; Y → ZW
Consid...

Consider a relational table R that is in 3NF, but not in BCNF. Which one of the following statements is TRUE?

Let the set of functional dependencies F = {QR → S, R → P, S → Q} hold on a relation schema X = (PQRS). X is not in BCNF. Suppose X is decomposed into...

Consider an Entity-Relationship (ER) model in which entity sets E1 and E2 are connected by an m : n relationship R12. E1 and E3 are connected by a 1 :...

Given the following two statements:
$$S1:$$ Every table with two single-valued attributes is in $$1NF, 2NF, 3NF$$ and $$BCNF.$$
$$S2:$$ $$AB \to C,\,\...

Relation $$R$$ has eight attribution $$ABCDEFGH.$$ Fields of $$R$$ contain only atomic values.
$$F = \left\{ {CH \to G,\,\,A \to BC,\,B \to CFH,\,\,E ...

Relation $$R$$ has eight attribution $$ABCDEFGH.$$ Fields of $$R$$ contain only atomic values.
$$F = \left\{ {CH \to G,\,\,A \to BC,\,B \to CFH,\,\,E ...

Consider the following relational schemes for a library database. Book ( Title, Author, Catalog_ no, Publisher, Year, Pr ice )
Collection ( Title, Aut...

Let $$R\left( {A,B,C,D} \right)$$ be a relational schema with the following functional dependencies:
$$A \to B,\,\,B \to C,\,\,C \to D$$ and $$D \to ...

Let $$R\left( {A,\,B,\,C,\,D,E,P,G} \right)$$ be a relational schema in which the following functional dependencies are known to hold: $$AB \to CD,\,...

Which one of the following statements if FALSE?

Consider the relation enrolled (student, course) in which (student, course ) is the primary key, and the relation Paid (student, amount) where student...

The following functional dependencies are given :
$$\eqalign{
& AB \to CD,\,AF \to D,\,\,DE \to F, \cr
& C \to G.\,\,\,\,\,\,\,\,\,\,F \...

In a schema with attributes $$A, B, C, D,$$ and $$E,$$ following set of functional dependencies are given
$$\eqalign{
& \,\,\,A \to B \cr
&...

Consider a relation scheme $$R = \left( {A,\,B,\,C,\,D,\,E,\,H} \right)$$ on which the following functional dependencies hold: $$\left\{ {A \to B,\,\,...

The relation scheme student Performance (Name, CourseNo, RollNo, Grade) has the following functional dependencies:
Name, courseNo $$\,\, \to \,\,$$ gr...

A relation Empdt $$1$$ is defined with attributes empcode (unique), name, street, city, state and pincode. For any pincode, there is only one city and...

Consider the following functional dependencies in a database.
$$\eqalign{
& \,\,\,\,Date\,\,of\,\,Birth\,\, \to \,\,Age \cr
& \,\,\,\,\,...

From the following instance of a relation schema $$R(A, B, C),$$ we can conclude that:
...

Relation $$R$$ is decomposed using a set of functional dependencies, $$F,$$ and relation $$S$$ is decomposed using another set of functional dependenc...

$$R(A,B,C,D)$$ is a relation. Which of the following does not have a lossless-join, dependency preserving $$BCNF$$ decomposition?

Given the following relation instance
$$\eqalign{
& X\,\,\,\,\,Y\,\,\,\,\,Z \cr
& \,\,1\,\,\,\,\,\,4\,\,\,\,\,\,2 \cr
& \,\,1\,\...

Consider the schema $$R = \left( {S\,\,T\,\,U\,\,V} \right)$$ and the dependencies $$S \to T,\,\,T \to U,\,\,U \to V$$ and $$V \to S$$ let $$R =$$ $$(...

Consider the following database relations containing the attributes
Book–id
Subject–Category–of–book
Name–of–Author
Nationality–of–Author
With book–id...

Consider the following database relations containing the attributes
Book–id
Subject–Category–of–book
Name–of–Author
Nationality–of–Author
With book–id...

Let $$R (a, b, c)$$ and $$S(d, e, f)$$ be two relations in which $$d$$ is the foreign key of $$S$$ that refers to the primary key of $$R.$$ Consider t...

For a database relation $$R(a,b,c,d),$$ where the domains of $$a, b, c, d$$ include only atomic values, only the following functional dependencies and...

(a) Consider the relation scheme $$R(A, B, C)$$ with the following functional dependencies:
$$\eqalign{
& A,B \to C \cr
& \,\,\,\,\,\,C ...