DBI202-PART 2 -Questions and Already Solved Solutions Correctly Updated.

DBI202-PART 2 -Questions and Already
Solved Solutions Correctly 2026-2027
Updated.


QN=22 (6811) The relational operator that adds all possible pairs of rows from two tables is
known as the .... operator.

a. union

b. product

c. join

d. selection - Answer b



QN=23 (7956) Let R(ABCDEFGH) satisfies the following functional dependencies:

A -> B,

CH -> A,

B -> E,

BD -> C,

EG -> H,

DE -> F.

Which of the following FDs is also guaranteed to be satisfied by R?

a. CGH -> BF

b. ACG -> DH

c. ADG -> CH

d. BCD -> FH - Answer c



QN=25 (7969) Consider a relation with schema R(A, B, C, D) and FD's BC -> D, D -> A, A -> B.
Which of the following is the key of R?

a. BD

b. BC

c. D

d. AB - Answer b



QN=26 (7963) Given the relation schema R(A,B,C) and functional dependencies

F = {AB-> C, B->A, C->B}.

,Which attribute(s) is/are prime?

a. only A

b. only B

c. A and B

d. B and C - Answer d



QN=27 (7971) Given the relation R(ABCDE) with the following FD's:

D -> C,

CE ->A,

D ->A, and

AE ->D

Which of the following attribute set is a key?

a. ABCDE

b. CDE

c. ABE

d. BD - Answer c



QN=29 (7967) A set of attributes forms a ____ for a relation if we do not allow 2-tuples in a
relation instance to have the same values in all that attributes

a. Key

b. Foreign Key

c. Index Key

d. Trigger Key - Answer a



QN=32 (7981) Suppose we have a relation R(ABCD) with FD's:

BC -> A ;

AD -> C ;

CD -> B ;

BD -> C

a. R is in BCNF

b. R is not in BCNF

c. All of the others

d. None of the others - Answer b



QN=38 (7977) The relation R(ABCD) has following FDs:

,{ AB -> C ; ABD -> C ; ABC -> D ; AC -> D}



Choose a correct statement about R?

a. R is in 3NF

b. R is not in 3NF

c. R is in BCNF - Answer b



QN=40 (7992) Normalization is a process of analyzing the given relation schema based on their
Functional Dependencies (FDs) and primary keys to achieve the following:

a. Minimizing redundancy

b. Minimizing insertion anomalies

c. All of the others

d. Minimizing deletion and update anomalies - Answer c



QN=43 (8003) Look at the following statements:

(a) For any relation schema, there is a dependency-preserving decomposition into 3NF

(b) For any relation schema, there is not dependency-preserving decomposition into 3NF

(c) For any relation schema, there is dependency-preserving decomposition into BCNF

(d) For some relation schema, there is not dependency-preserving decomposition into BCNF

a. (a) and (d) are true

b. (a) and (b) are true

c. (a) and (c) are true

d. (b) and (d) are true - Answer a



QN=44 (8007) Look at the following statements:

(a)All relations in 3NF are also in 2NF

(b)All relations in 2NF are also in 1NF

(c)All relations in 1NF are also in BCNF

(d)All relations in 1NF are also in 3NF

a. (b) and (d) are true

b. (a) and (c) are true

c. (a) and (d) are true

d. (a) and (b) are true - Answer d



QN=45 (8006) What is "normalization"?

, a. Normalizing data means eliminating redundant information from a table and organizing the
data so that future changes to the table are easier

b. Normalizing data means minimizing columns from a table and organizing the data so that
future changes to the table will be made more quickly

c. Normalizing data means removing columns from a table and organizing the data so that
future changes to the table will be made more quickly

d. Normalizing data means adding more columns to a table and organizing the data so that
future changes to the table will be made more quickly - Answer a



QN=46 (7997) Which of the following are guidelines for designing the relational schema ?

a. Reduce the redundant values in tuples

b. Reduce the NULL values in tuples

c. Always make relations 3NF

d. All of the others - Answer d



Regardless of whatever any other transaction is doing, a transaction must be able to continue
with the exact same data set it started with.

The above describes which property of a transaction?

a. Atomic

b. Isolation

c. Consistency

d. Durability - Answer b



Pay attention into the following query:



SELECT * FROM R

WHERE A LIKE '%a%';



So, in the above case, the wildcard % represents what?

a. % (percent sign) represents zero, one, or more character

b. % (percent sign) represents exactly 1 character - Answer a



With SQL, how do you select all the records from a table named "Persons" where the value of
the column "FirstName" starts with an "a"?

a. SELECT * FROM Persons WHERE FirstName='a'

b. SELECT * FROM Persons WHERE FirstName LIKE '%a'

c. SELECT * FROM Persons WHERE FirstName='%a%'