DBMS Interview Questions and Answers in 2025 (100+ Q&A)

DBMS

Ques:- What is the purpose of normalization in DBMS?

Asked In :-

Right Answer:
The purpose of normalization in DBMS is to reduce data redundancy and improve data integrity by organizing data into tables and establishing relationships between them.

DBMS

Ques:- What is meant by a Database?

Asked In :-

Right Answer:
A database is an organized collection of structured information or data, typically stored electronically in a computer system, that can be easily accessed, managed, and updated.

DBMS

Ques:- What is DBMS used for?

Asked In :-

Right Answer:
DBMS (Database Management System) is used for storing, managing, and retrieving data efficiently and securely in databases.

DBMS

Ques:- Why we cannot use WHERE clause with aggregate functions like HAVING ?

Asked In :-

Right Answer:
We cannot use the WHERE clause with aggregate functions because the WHERE clause filters rows before any aggregation occurs, while the HAVING clause filters after aggregation has been performed.

DBMS

Ques:- Name the student who has secured third highest marks using sub queries.

Asked In :-

Right Answer:
```sql
SELECT name FROM students
WHERE marks = (SELECT DISTINCT marks FROM students ORDER BY marks DESC LIMIT 1 OFFSET 2);
```

DBMS

Ques:- What is the difference between primary key and unique constraints?

Asked In :-

Right Answer:
A primary key uniquely identifies each record in a table and cannot contain NULL values, while a unique constraint also ensures uniqueness but can allow one NULL value.

DBMS

Ques:- What are super, primary, candidate and foreign keys?

Asked In :-

Right Answer:
- **Primary Key**: A unique identifier for each record in a table; it cannot contain NULL values.
- **Candidate Key**: A set of attributes that can uniquely identify a record; one of these keys is chosen as the primary key.
- **Super Key**: A set of one or more attributes that can uniquely identify a record; it may contain additional attributes beyond those necessary for uniqueness.
- **Foreign Key**: An attribute or set of attributes in one table that refers to the primary key in another table, establishing a relationship between the two tables.

DBMS

Ques:- What are advantages of DBMS over traditional file based systems?

Asked In :-

Right Answer:
1. Data Integrity: Ensures accuracy and consistency of data.
2. Data Security: Provides access controls and user permissions.
3. Data Redundancy Control: Reduces data duplication and inconsistency.
4. Data Relationships: Supports complex relationships between data.
5. Data Backup and Recovery: Offers automated backup and recovery options.
6. Multi-user Access: Allows multiple users to access and manipulate data simultaneously.
7. Improved Data Management: Facilitates easier data organization and retrieval.
8. Querying Capabilities: Supports complex queries through SQL.

DBMS

Ques:- What is DBMS?

Asked In :-

Right Answer:
A DBMS (Database Management System) is software that allows users to create, manage, and manipulate databases, enabling efficient storage, retrieval, and organization of data.

The DBMS (Database Management System) category on takluu.com is designed for students, IT professionals, and job seekers eager to master the fundamentals and advanced concepts of databases. In today’s data-driven world, understanding how databases work is critical for roles in software development, data analysis, and system administration.

This category covers core topics such as database models (relational, hierarchical, network), SQL queries, normalization, transactions, indexing, and database security. You’ll also learn about practical aspects like database design, backup and recovery, and performance optimization.

Interview questions often test your knowledge of how to efficiently manage large volumes of data, ensure data integrity, and implement secure database solutions. Knowing DBMS concepts helps you handle real-world challenges related to data storage and retrieval effectively.

At Takluu, we simplify complex DBMS topics with clear explanations, practical examples, and common interview questions. Whether you’re preparing for technical interviews or exams, this category equips you with the skills to confidently answer questions and solve problems related to databases.

Mastering DBMS opens doors to exciting career opportunities in software development, database administration, and data science. With our resources, you’ll be well-prepared to succeed and excel in the data-centric tech industry.

Questions in: DBMS

What makes Takluu valuable for interview preparation?

Get Our Mobile App

Programming

Reasoning

Network & Telecom

Management

What makes Takluu valuable for interview preparation?