Normalization in Database Management

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Question 1

Which of the following is TRUE?

(GATE 2012 | MCQ | 1-mark)

  • Every relation in 3NF is also in BCNF

  • A relation R is in 3NF if every non-prime attribute of R is fully functionally dependent on every key of R

  • Every relation in BCNF is also in 3NF

  • No relation can be in both BCNF and 3NF

Question 2

Which of the following violates 1NF?

  • Atomic column values

  • Unique rows

  • Multiple values in one cell

  • Unique column names

Question 3

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

(GATE 1998 | MCQ | 1-mark)

  • 2 NF

  • 3 NF

  • 4 NF

  • BCNF

Question 4

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

(GATE 2001 | MCQ | 2-mark)

  • A→B, B→CD

  • A  → B, B → C, C→D

  •  AB →C, C → AD

  • A →BCD

Question 5

The relation scheme student Performance (Name, CourseNo, RollNo, Grade) has the following functional dependencies:

Name, courseNo → grade

RollNo, courseNo → grade

Name → rollNo

RollNo → name

The highest normal form of this relation scheme is -

(GATE 2004 | MCQ | 2-mark)

  • 2NF

  • 3NF

  • BCNF

  • None

Question 6

Relation R with an associated set of functional dependencies, F, is decomposed into BCNF. The redundancy (arising out of functional dependencies) in the resulting set of relations is - 

(GATE 2002 | MCQ | 1-mark)

  • Zero

  • More than zero but less than that of an equivalent 3NF decomposition

  • Proportional to the size of F+

  • Indeterminate

Question 7

Which of the following must be true for a relation to be in BCNF?

  • Every determinant is a candidate key

  • It contains no transitive dependencies

  • It must have only one table

  • Every attribute must be a key


Question 8

Consider the following relational schemes for a library database. Book (Title, Author, Catalog_no, Publisher, Year, Price) Collection (Title, Author, Catalog no)

With in the following functional dependencies:

I. Title Author → Catalog_no

II. Catalog_no→ Title Author Publisher Year

III. Publisher Title Year → Price

Assume { Author, Title } is the key for both schemes. Which of the following statements is true?

(GATE 2001 | MCQ | 2-mark)

  • Both Book and Collection are in BCNF

  • Both Book and Collection are in 3 NF only

  • Book is in 2 NF and Collection is in 3 NF

  • Both Book and Collection are in 2 NF only

Question 9

What does 5NF aim to eliminate?

  • Transitive dependency

  • Join dependency

  • Multi-valued dependency

  • Partial dependency

Question 10

Given the following two statements:

S1: Every table with two single-valued attributes is in 1NF, 2NF, 3NF, and BCNF.

S2:

AB → C, D → E, E → C is a minimal cover for the set of functional dependencies:

AB → C, D → E, AB → E, E → C.

Which one of the following is CORRECT?

(GATE 2014 | SET-1 MCQ | 2-mark)

  • S1 is TRUE and S2 is FALSE.

  • Both S1 and S2 are TRUE.

  • S1 is FALSE and S2 is TRUE.

  • Both S1 and S2 are FALSE.

There are 10 questions to complete.

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