Competitive Exams : Computer Awareness - DBMS (Set 2)

Question 1

A banking system needs to ensure that every customer account has a unique account number and that this number is never left blank.

Which two integrity constraints are primarily enforced to meet these requirements?

Accepted Answer

A) Primary Key and Not Null

Answer

B) Foreign Key and Unique

Answer

C) Check Constraint and Referential Integrity

Answer

D) Domain Constraint and Assertions

Answer

E) Unique and Default

Question 2

Which of the following normal forms is based on the concept of full functional dependency?

Accepted Answer

C) Second Normal Form (2NF)

Answer

A) First Normal Form (1NF)

Answer

B) Boyce-Codd Normal Form (BCNF)

Answer

D) Third Normal Form (3NF)

Question 3

Which SQL clause is used to filter groups based on aggregate function results?

Accepted Answer

B) HAVING

Answer

A) WHERE

Answer

C) GROUP BY

Answer

D) ORDER BY

Question 4

In an ER model, if one instance of entity A can be associated with zero or many instances of entity B, and one instance of entity B can be associated with zero or many instances of entity A, what is the cardinality of the relationship?

Accepted Answer

A) Many-to-Many

Answer

B) One-to-Many

Answer

C) One-to-One

Answer

D) Many-to-One

Question 5

Which of the following ACID properties ensures that either all operations of a transaction are completed or none are?

Accepted Answer

A) Consistency

Answer

B) Atomicity

Answer

C) Isolation

Answer

D) Durability

Question 6

A key that contains a minimal set of attributes that uniquely identifies a tuple in a relation is called a:

Accepted Answer

D) Candidate Key

Answer

A) Primary Key

Answer

B) Foreign Key

Answer

C) Super Key

Question 7

To retrieve the total number of employees in each department, which of the following SQL functions and clauses would you primarily use?

Accepted Answer

C) COUNT and GROUP BY

Answer

A) SUM and WHERE

Answer

B) AVG and ORDER BY

Answer

D) MAX and HAVING

Question 8

Which indexing technique is most suitable for range queries and maintaining sorted order of data?

Accepted Answer

B) B-Tree Index

Answer

A) Hash Index

Answer

C) Bitmap Index

Answer

D) Clustered Index (always)

Question 9

In a 3-tier database architecture, which tier typically hosts the application logic and business rules?

Accepted Answer

D) Application Tier

Answer

A) Data Tier

Answer

B) Presentation Tier

Answer

C) Client Tier

Question 10

Which type of integrity constraint ensures that a value in one table's foreign key column must exist as a primary key value in another related table?

Accepted Answer

A) Referential Integrity

Answer

B) Entity Integrity

Answer

C) Domain Integrity

Answer

D) User-defined Integrity

Question 11

Which of the following SQL commands is part of Data Manipulation Language (DML)?

Accepted Answer

B) INSERT INTO

Answer

A) CREATE TABLE

Answer

C) ALTER TABLE

Answer

D) DROP TABLE

Question 12

In the context of concurrent transactions, what is a state where two or more transactions are waiting indefinitely for each other to release resources?

Accepted Answer

A) Livelock

Answer

B) Starvation

Answer

C) Inconsistency

Answer

D) Deadlock

Question 13

Boyce-Codd Normal Form (BCNF) is stricter than 3NF. A relation is in BCNF if and only if for every non-trivial functional dependency $X o Y$, $X$ is a:

Accepted Answer

A) Superkey

Answer

B) Primary Key

Answer

C) Foreign Key

Answer

D) Candidate Key

Question 14

What is the primary purpose of creating a 'view' in a database?

Accepted Answer

C) To provide a customized and simplified representation of the data.

Answer

A) To store data permanently for backup.

Answer

B) To improve the performance of data insertion.

Answer

D) To enforce unique values in a column.

Question 15

Consider the SQL query: SELECT EmpName FROM Employees WHERE DeptID IN (SELECT DeptID FROM Departments WHERE Location = 'New York'$)$. What type of SQL query is this?

Accepted Answer

B) Subquery

Answer

A) Self-Join Query

Answer

C) Correlated Query

Answer

D) Aggregate Query

Question 16

Which relational algebra operation selects rows (tuples) from a relation that satisfy a given predicate?

Accepted Answer

A) Selection ($\sigma$)

Answer

B) Projection ($\pi$)

Answer

C) Union ($\cup$)

Answer

D) Join ($\bowtie$)

Question 17

In which file organization method are records stored in no particular order, and new records are simply added to the end of the file?

Accepted Answer

C) Heap File Organization

Answer

A) Sequential File Organization

Answer

B) Indexed Sequential File Organization

Answer

D) Hash File Organization

Question 18

Which of the following is NOT typically a primary responsibility of a Database Administrator (DBA)?

Accepted Answer

D) Application Development Logic

Answer

A) Database Security Management

Answer

B) Backup and Recovery

Answer

C) Performance Tuning

Question 19

Which data model organizes data in a tree-like structure, where each child record has only one parent record?

Accepted Answer

A) Hierarchical Model

Answer

B) Network Model

Answer

C) Relational Model

Answer

D) Object-Oriented Model

Set 2Competitive Exams : Computer Awareness - DBMS