Introduction
India’s Database Management System market generated a revenue of USD 2.5 billion in 2024, and it is expected to reach USD 7.5 billion by 2030. This highlights the need for skilled professionals in the field.
Are you preparing for a tech interview? If yes, you must be looking for the most commonly asked DBMS viva questions. You are not alone in this. Industries are increasingly relying on data-driven systems, making Database Management Systems (DBMS) a foundational concept for these interviews.
DBMS questions are asked in interviews for roles in system design, software development, and data engineering. However, the basics are no longer enough for these. You must have in-depth knowledge to answer. It is also important to know about the most commonly asked questions for these interviews. This is what this blog will help you with.
Read below to learn how to answer the most frequently asked DBMS viva questions.
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Latest DBMS 2026 Questions
In addition to DBMS database concepts, you must also know about the frequently asked questions to practice for the interviews. Below are some of the most common ones and how you should answer them.
Basic Database Interview Questions
Below are some basic questions that an interviewer might ask. These primarily involve definitions and DBMS keys interview questions.
Explain DMS and its importance.
A DBMS is a software application. It allows users to create, define, manage, and manipulate databases. Managing large amounts of data becomes chaotic without a DBMS. It helps ensure the secure storage of data. Additionally, it offers recovery, backup, and disaster management tools for data.
Explain the difference between a primary key and a foreign key.
A primary key is a unique identifier for each record within a table. On the other hand, a foreign key creates a link between two tables. It establishes a relationship between two tables, while a primary key maintains uniqueness within its own table.
Explain the different types of DBMS.
There are varying types of DBMS based on their unique structures and use cases. The most common ones are Network DBMS, Object-Oriented DBMS, Hierarchical DBMS, and Relational DBMS. Each DBMS type offers unique advantages. However, relational databases are most commonly used due to their flexibility. These are also easy to use and scalable.
Database Interview Questions for Freshers
A database interview for freshers involves questions primarily on foundational concepts. Below are some common ones with their answers.
What is a B-tree in a DBMS?
A B-tree refers to a Balanced Tree in a DBMS. It is a self-balancing data structure that organises data for efficient insertion, searching, and deletion operations. This structure is used to allow fast access to data by implementing indexes.
What are clustered and non-clustered indexes in a DBMS?
A clustered index has its data rows stored in the same order as the index itself. This means the data in a table is physically organised according to the clustered index. In contrast, a non-clustered index does not alter the physical order of a table’s data rows. Instead, it creates a separate data structure to store pointers.
Explain the difference between UNION and INTERSECT.
UNION and INTERSECT are SQL’s set operations. They are used for result combinations from two or more SELECT queries. However, these work in different ways. UNION operations return unique rows while INTERSECT returns only the common rows between the result sets.
DBMS Technical Interview Questions
DBMS transactions interview questions are usually asked when testing your technical knowledge. However, below are some other questions you must prepare for:
What is a transaction in a DBMS?
The sequence of operations performed on the database is known as a transaction. These are used to ensure the integrity and consistency of data. A transaction is especially useful in a multi-user environment. It must follow Atomicity, Consistency, Isolation, and Durability.
Explain Relational DBMS vs NoSQL.
Relational DBMS is ideal for complex ACID transactions and queries. It uses structured tables and fixed schemas. On the other hand, NoSQL is compatible with big data and real-time applications. It provides horizontal scalability and flexible schemas.
What is a schema in a DBMS?
A schema is the structure of a database. It defines the way of data organisation and relationships between the established data. A schema includes definitions of indexes, views, tables, and other database objects.
DBMS Queries Interview Questions
Queries are another important concept that is often asked about in DBMS tech interviews. Below are some of the frequently asked questions.
Explain the database instance.
A database instance refers to a specific DBMS running copy. This copy manages data for a particular database. An instance includes memory structures, background processes, and database files. It interacts with the physical data files while ensuring data is retrieved, updated, and stored.
What is a surrogate key?
A surrogate key in a DBMS is a unique identifier for an entity. It is used in place of a natural key. These keys are created artificially and have no inherent meaning. They are used in situations where natural keys are not suitable due to their length.
What is data redundancy?
Data redundancy is the unnecessary repetition of data. It can lead to inefficiencies and inconsistencies. This is where normalisation is used. It breaks down data into relatable, smaller tables. As a result, normalisation avoids redundancy and minimises duplication to ensure every data piece is stored only once.
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Conclusion
DBMS viva questions are an essential part of preparing for any tech interview today, where Database Management Systems are used across industries. Also, if you are looking forward to enhancing your knowledge in these systems or pursuing a career in the same, Amity University Online’s Certification course in Database Management Using SQL and MongoDB is the right option for you. The certification can help you excel in your tech interviews and get your dream job in a DBMS-related role.
