Computer Knowledge

Database Management Systems

5,344 Questions

Database Management Systems (DBMS) form the core framework for data storage, retrieval, and security in modern software applications. Concepts such as the E-R model, backup planning, SQL integration, and big data architecture are essential for computer knowledge sections. This hub offers a comprehensive set of practice questions to master DBMS fundamentals and advanced database operations.

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Database Management Systems Questions

Multiple choice

How many types of keys are there in relational database?

  1. 9

  2. 7

  3. 8

  4. 6

  5. None of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

There are seven types of keys in relational database. These are: 1.) Primary key 2.) Candidate key 3.) Super key 4.) Foreign key 5.) Alternate key 6.) Artificial key 7.) Composite key So, this is the correct answer.

Multiple choice

Which of the following entity sets does not have a primary key?

  1. Composite entity set

  2. Weak entity set

  3. Strong entity set

  4. Derived entity set

  5. None of these

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

This is the correct answer. The entity set that doesn’t have sufficient attributes to form a primary key and relies on another for its identification is called a weak entity set. It doesn’t have a primary key. So, this is the correct answer.

Multiple choice

How many types of attributes are there in relational database?

  1. 6

  2. 5

  3. 4

  4. 3

  5. None of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

There are five types of attributes in relational database. These are: 1.) Simple attribute 2.) Composite attribute 3.) Single-valued attribute 4.) Multivalued attribute 5.) Derived attribute So, this is the correct answer.

Multiple choice

How many types of data models are there in DBMS?

  1. 5

  2. 4

  3. 3

  4. 2

  5. None of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

There are 3 types of data models present in DBMS. These are: 1.) Object based data model 2.) Record based data model 3.) Physical data model So, this is the correct answer.

Multiple choice

A data warehouse is which of the following?

  1. Can be updated by the end users

  2. Contains numerous naming conventions and formats

  3. Organized around important subject areas

  4. Contains only current data

  5. None of these

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Data warehouses integrate data from multiple source systems, which inherently contain different naming conventions and formats. During extraction and loading (ETL), the warehouse must handle these diverse formats before standardizing them for analysis.

Multiple choice

A database management system (DBMS) is a

  1. hardware system used to create, maintain and provide controlled access to a database

  2. hardware system used to create, maintain and provide uncontrolled access to a database

  3. software system used to create, maintain and provide uncontrolled access to a database

  4. software system used to create, maintain and provide controlled access to a database

  5. None of these
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Option (4) is the correct answer.

Multiple choice

Which of the following is true?

  1. Logical design is software-dependent

  2. In a distributed database, database is stored in one physical location

  3. Conceptual design translates the logical design into internal model

  4. Logical design is software independent

  5. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Multiple choice

Which of the following does not describe a data warehouse?

  1. Subject-oriented

  2. Integrated

  3. Time-variant

  4. Updateable

  5. None of these
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Data warehouses are subject-oriented, integrated, time-variant, and NON-VOLATILE (not updateable). They are designed for read-only analytical processing, not transactional updates. 'Updateable' is the characteristic that does NOT describe a data warehouse, making option D the correct answer to this negative-question.

Multiple choice

A computer-based information system

  1. is a developing data

  2. is a system in which a computer is used to process data to get information

  3. performs complex mathematical calculations

  4. is one in which data is put into the computer for processing
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A computer-based information system is fundamentally defined as a system where computers process data to generate meaningful information. This distinguishes it from mere data entry or calculation systems. The emphasis is on the transformation of raw data into organized, useful information through computer processing.