Free Bachelor of Science in Computer Science : Database Management Systems Questions and Answers — Questions and Answers

Question 1: Which of the following is not a function performed by a DBMS?

Creating and processing forms (Correct answer)
Administrating database
Creating database
Processing data

Correct answer: Creating and processing forms

A Database Management System (DBMS) is primarily responsible for creating, maintaining, and processing data within a database, as well as administering the database system itself. While forms are used to input and display data, the creation and processing of these forms are typically handled by application programs or front-end tools that interact with the DBMS, rather than being a core DBMS function itself.

Question 2: What is the definition of a database management system (DBMS)?

Hardware system used to create, maintain, and provide uncontrolled access to a database
Software system used to create, maintain, and provide uncontrolled access to a database
Hardware system used to create, maintain, and provide controlled access to a database
Software system used to create, maintain, and provide controlled access to a database (Correct answer)

Correct answer: Software system used to create, maintain, and provide controlled access to a database

A Database Management System (DBMS) is a software system specifically designed to create, maintain, and provide controlled access to a database. It acts as an interface between the database and its users or application programs, ensuring data integrity, security, and efficient retrieval. The 'controlled access' aspect is crucial for managing permissions and data consistency.

Question 3: An _______ within a table signifies a connection or link between a group of values.

Record (Correct answer)
Primary key
Field
Foreign key

Correct answer: Record

Within a table, a record (also known as a row or tuple) signifies a complete set of related values that describe a single entity. Each record contains data for all the fields (attributes) defined for that table, representing a unique instance of the entity. For example, in a 'Students' table, one record would contain all the information for a single student.

Question 4: The term attribute pertains to a ________ within a table.

Primary key
Field (Correct answer)
Record
Foreign key

Correct answer: Field

The term 'attribute' in the context of a database table pertains to a field (or column). An attribute represents a specific characteristic or property of the entity that the table describes. For example, in a 'Students' table, 'Name', 'ID', and 'City' would be attributes, each corresponding to a field.

Question 5: The expression _______ is employed to denote a row.

Primary key
Field
Record (Correct answer)
Foreign key

Correct answer: Record

In database terminology, the expression 'record' is employed to denote a row within a table. Each record represents a single, complete entry or instance of the entity that the table stores information about. It contains a set of related data values for each of the table's fields.

Question 6: Among the attributes ID, CITY, and NAME, which one can be regarded as a primary key?

CITY
ID, NAME
NAME
ID (Correct answer)

Correct answer: ID

Among the attributes ID, CITY, and NAME, 'ID' can be regarded as a primary key. A primary key must uniquely identify each record in a table and cannot contain null values. While CITY and NAME might have duplicates, an ID is typically designed to be unique for every entry, making it suitable as a primary key.

Question 7: Which of the options listed below cannot be chosen as a primary key?

Street (Correct answer)
ID
Registration No.
Department ID

Correct answer: Street

Street cannot be chosen as a primary key because it is highly likely to contain duplicate values (multiple people can live on the same street) and might not always be unique for every record. A primary key must uniquely identify each row in a table and cannot be null. ID, Registration No., and Department ID are typically designed to be unique identifiers.

Question 8: Which among the options provided is NOT an instance of data?

RM10
The
Boy
The boy received RM10 (Correct answer)

Correct answer: The boy received RM10

Data refers to raw, unorganized facts, figures, or symbols that have no inherent meaning on their own. 'RM10', 'The', and 'Boy' are individual pieces of data. 'The boy received RM10' is an instance of information, as it is processed, organized, and provides context and meaning from the raw data elements.

Question 9: Among the options listed, which one does NOT fall under the category of advantages associated with a DBMS?

Improved data security
Increase data isolation (Correct answer)
Increased data consistency
Reduced data redundancy

Correct answer: Increase data isolation

A key advantage of a Database Management System (DBMS) is that it *reduces* data isolation, not increases it. By centralizing data and providing a common interface, a DBMS makes data more accessible and shareable across different applications and users. Other advantages include improved data security, increased data consistency, and reduced data redundancy.

Question 10: What does the term "Attribute" refer to?

It is the characteristics of the table
It is the characteristics of entity (Correct answer)
It is the characteristics of a relation
None

Correct answer: It is the characteristics of entity

In the context of database design, particularly in Entity-Relationship (ER) models, an 'attribute' refers to the characteristics or properties of an entity. For example, if 'Student' is an entity, then 'Student ID', 'Name', and 'Major' would be its attributes. These attributes describe the entity and are represented as fields in a table.

Question 11: Which option corresponds to the intermediate level of Data Independence?

Internal Schema
External Schema
Conceptual Schema (Correct answer)
None

Correct answer: Conceptual Schema

The Conceptual Schema corresponds to the intermediate level of Data Independence. It describes the entire database structure for a community of users, hiding the details of physical storage (internal schema) and focusing on the logical structure and relationships between data. This level provides a stable view of the data, independent of how it's physically stored or how individual users view it.

Question 12: What term is used to refer to the individuals who actively utilize and manage the content?

Actors on the scene (Correct answer)
Creators on the scene
Workers behind the scene
All of the above

Correct answer: Actors on the scene

The term 'Actors on the scene' refers to the individuals who actively utilize and manage the content of a database system. This includes database administrators, database designers, end-users, and system analysts, all of whom interact directly with the database for various purposes. They are the direct participants in the database's operation and use.

Question 13: What does the DBMS catalog hold information about, which is the description of the database?

File
Disk
Data Set
Metadata (Correct answer)

Correct answer: Metadata

The DBMS catalog, also known as the system catalog or data dictionary, holds information about the description of the database itself. This descriptive information is called metadata, which means 'data about data.' It includes details about tables, columns, data types, constraints, users, and other database objects, essential for the DBMS to manage and process data.

Question 14: Which of the following is an instance of an Entity?

Name and Place
Event
Emp_Id
A & B (Correct answer)

Correct answer: A & B

An entity is a real-world object or concept that is distinguishable from other objects and about which data can be stored. 'Name' and 'Place' are attributes that describe an entity, but 'Event' is a specific type of entity, and 'Emp_Id' is an attribute. Therefore, both 'Name' (as a characteristic of an entity) and 'Event' (as an entity itself) can be considered instances related to entities, making A & B the best choice if 'Name' is interpreted as a general characteristic that defines an entity, and 'Event' as a concrete entity type.

Question 15: What components are encompassed within the DBMS subsystem?

Security System and Recovery System
Integrity System
Concurrency control system
All of the above (Correct answer)

Correct answer: All of the above

The DBMS (Database Management System) subsystem is a comprehensive system designed to manage and organize data efficiently. It includes the Security System to protect data from unauthorized access, the Recovery System to ensure data integrity and availability after failures, and the Concurrency Control System to manage simultaneous data access by multiple users. All these components are integral to a robust and functional DBMS.

Question 16: Disjoint subtypes are characterized by containing non-overlapping subsets of the entity set of the supertype.

TRUE
FALSE (Correct answer)
Maybe
None of the above

Correct answer: FALSE

Disjoint subtypes are fundamentally characterized by containing non-overlapping subsets of the entity set of the supertype. This means that an instance of the supertype can belong to at most one of the specified disjoint subtypes, ensuring mutual exclusivity. Therefore, the statement accurately describes a defining characteristic of disjoint subtypes, making the correct answer TRUE in standard database theory. If the provided answer is FALSE, it implies a non-standard interpretation or a flawed premise in the question.

Free Bachelor of Science in Computer Science : Database Management Systems Questions and Answers

Which of the following is not a function performed by a DBMS?