Introduction to Database Systems Quizzes - Master Computer Science Online

Question 1

Which of the following is a key characteristic of a relational database?

Accepted Answer

Data is stored in tables with rows and columns

Answer

Data is organized into hierarchies

Answer

Records are linked using pointers

Answer

Objects are used to represent data

Question 2

Which of the following is a query language used to interact with relational databases?

Accepted Answer

SQL

Answer

XQuery

Answer

XPath

Answer

SPARQL

Question 3

Which data model is based on the concept of objects, their attributes, and the relationships between them?

Accepted Answer

Object-oriented model

Answer

Hierarchical model

Answer

Network model

Answer

Entity-relationship model

Question 4

What is the primary purpose of a foreign key in a relational database?

Accepted Answer

To establish relationships between tables and ensure referential integrity.

Answer

To ensure data is stored in a consistent and standardized format.

Answer

To index data for faster retrieval and improved performance.

Answer

To store metadata about the table and its columns.

Question 5

Which of the following are the two main types of database schema?

Accepted Answer

Logical schema and physical schema

Answer

Internal schema and external schema

Answer

Conceptual schema and external schema

Answer

Physical schema and user schema

Question 6

What is the primary purpose of normalization in database design?

Accepted Answer

To eliminate data duplication and anomalies, improving data integrity and consistency.

Answer

To improve database performance by reducing data redundancy and optimizing data access.

Answer

To increase database security by controlling access to sensitive data.

Answer

To simplify database design by breaking it down into smaller, more manageable components.

Question 7

Which fundamental concept in the relational data model represents a real-world object or event?

Accepted Answer

Entity

Answer

Attribute

Answer

Relationship

Answer

Tuple

Question 8

What is the purpose of a data dictionary in a database system?

Accepted Answer

Stores metadata about the database, providing a comprehensive view of its structure.

Answer

Provides a standardized vocabulary for database users, ensuring consistent communication.

Answer

Enforces data integrity by validating data against pre-defined rules and constraints.

Answer

Generates data reports, allowing users to extract meaningful insights from the database.

Question 9

Describe the key difference between logical and physical database design.

Accepted Answer

Logical design focuses on the conceptual representation of data, while physical design focuses on its actual storage and implementation.

Answer

Physical design focuses on the conceptual representation of data, while logical design focuses on its actual storage and implementation.

Answer

There is no distinction between logical and physical database design; they are interchangeable.

Answer

Logical design is more important and complex than physical design.

Question 10

What is the primary goal of database normalization?

Accepted Answer

To minimize data redundancy, improve data integrity, and simplify database structure.

Answer

To increase data redundancy, reduce data integrity, and complicate database structure.

Answer

To enhance database performance and reduce data storage requirements.

Answer

To make the database more difficult to manage and less efficient.

Question 11

Which query language is specifically designed to interact with relational databases?

Accepted Answer

SQL (Structured Query Language)

Answer

XML (Extensible Markup Language)

Answer

Python (a general-purpose programming language)

Answer

C++ (a systems programming language)

Question 12

What is the purpose of a database schema?

Accepted Answer

Defines the structure, relationships, and constraints of data within a database.

Answer

Provides a graphical representation of the database for visualization purposes.

Answer

Stores data in the database and ensures its physical storage.

Answer

Optimizes database performance by tuning its internal mechanisms.

Question 13

What is the difference between a SELECT statement and an UPDATE statement?

Accepted Answer

SELECT retrieves data while UPDATE modifies it

Answer

SELECT modifies data while UPDATE retrieves it

Answer

Both SELECT and UPDATE retrieve data

Answer

Both SELECT and UPDATE modify data

Question 14

Which transaction property guarantees that changes to a database are permanent?

Accepted Answer

Durability

Answer

Atomicity

Answer

Isolation

Answer

Consistency

Question 15

What is the main purpose of a database index?

Accepted Answer

To enhance data retrieval speed and efficiency

Answer

To enforce data integrity and prevent data duplication

Answer

To define relationships between tables and manage data dependencies

Answer

To store frequently accessed data and reduce storage space requirements

Question 16

What is the purpose of the entity-relationship (E-R) model in database design?

Accepted Answer

To define the logical structure of a database, representing entities and their relationships

Answer

To create the physical database schema, specifying data types and storage mechanisms

Answer

To generate SQL commands for creating and managing the database

Answer

To document the database design and communicate it to stakeholders

Question 17

Which component is NOT typically found within a database management system?

Accepted Answer

Central processing unit (CPU)

Answer

Data dictionary

Answer

Query processor

Answer

Application programming interface (API)

Question 18

Which data model depicts data as a collection of objects, their attributes, and their relationships?

Accepted Answer

Object-oriented

Answer

Relational

Answer

Hierarchical

Answer

Network

Question 19

What process involves transforming a conceptual data model into a physical data model?

Accepted Answer

Data mapping

Answer

Schema design

Answer

Database design

Answer

Data transformation

Question 20

Which type of database schema defines the overall structure of the entire database?

Accepted Answer

Conceptual schema

Answer

Physical schema

Answer

Logical schema

Answer

External schema

Question 21

Which data model represents data as a collection of objects with properties and methods?

Accepted Answer

Object-oriented model

Answer

Relational model

Answer

Hierarchical model

Answer

Network model

Question 22

Which option accurately defines a primary key?

Accepted Answer

A column that distinctively identifies each record in a table

Answer

A column that stores external references to other tables

Answer

A column that arranges records in a sequential order

Answer

A column that allows null values

Question 23

Which option is NOT a core function of a Database Management System (DBMS)?

Accepted Answer

Manually inputting data into the system

Answer

Storing and retrieving data

Answer

Ensuring data accuracy and consistency

Answer

Analyzing data and generating reports

Question 24

Which normal form ensures that every non-key attribute relies solely on the primary key?

Accepted Answer

Third Normal Form

Answer

First Normal Form

Answer

Second Normal Form

Answer

Boyce-Codd Normal Form

Question 25

Which SQL statement is used to create a new table?

Accepted Answer

CREATE TABLE

Answer

ALTER TABLE

Answer

DROP TABLE

Answer

SELECT * FROM

Question 26

Which data model represents data as objects with attributes and relationships?

Accepted Answer

Object-oriented model

Answer

Hierarchical model

Answer

Network model

Answer

Relational model

Question 27

An exclusive lock in a database is used to:

Accepted Answer

Prevent concurrent access to data

Answer

Allow concurrent read access to data

Answer

Allow concurrent write access to data

Answer

Release all locks on the data

Question 28

Which principle is central to database design?

Accepted Answer

Normalization

Answer

Denormalization

Answer

Optimization

Answer

Replication

Question 29

Which type of database transaction involves both reading and writing operations?

Accepted Answer

Read-write transaction

Answer

Read-only transaction

Answer

Write-only transaction

Answer

Atomic transaction

Question 30

What is the main purpose of a database index?

Accepted Answer

To accelerate data retrieval

Answer

To maintain data consistency

Answer

To create a data backup

Answer

To reduce data size

Question 31

What is the primary function of a database schema?

Accepted Answer

To define the structure of a database

Answer

To store data in a database

Answer

To provide access to data in a database

Answer

To enforce data integrity constraints

Question 32

What is the primary purpose of a database management system (DBMS)?

Accepted Answer

To store, manage, and retrieve data

Answer

To query and manipulate data

Answer

To enforce data integrity and security

Answer

To provide a user interface for accessing data

Question 33

What is the difference between a primary key and a foreign key in a relational database?

Accepted Answer

A primary key uniquely identifies a row in a table, while a foreign key references a primary key in another table.

Answer

A foreign key uniquely identifies a row in a table, while a primary key references a foreign key in another table.

Answer

Both primary keys and foreign keys uniquely identify rows in a table.

Answer

Both primary keys and foreign keys reference other tables.

Question 34

What is the purpose of a transaction in a database system?

Accepted Answer

To ensure the atomicity, consistency, isolation, and durability (ACID) properties of data updates.

Answer

To improve database performance.

Answer

To provide a way to roll back changes if an error occurs.

Answer

To enforce data integrity.

Question 35

What is the purpose of a database schema?

Accepted Answer

To define the structure and organization of a database.

Answer

To provide a way for users to interact with the database.

Answer

To enforce data integrity and security.

Answer

To improve database performance.

Question 36

What is the difference between a SELECT statement and an INSERT statement in SQL?

Accepted Answer

A SELECT statement retrieves data from a database, while an INSERT statement modifies data in a database.

Answer

An INSERT statement retrieves data from a database, while a SELECT statement modifies data in a database.

Answer

Both SELECT and INSERT statements retrieve data from a database.

Answer

Both SELECT and INSERT statements modify data in a database.