Top SQL Interview Questions and Answers for Freshers
If you’re preparing for your first job interview in IT, data analytics, or database management, there’s one skill you absolutely cannot ignore: SQL (Structured Query Language). Almost every recruiter will test your knowledge of SQL basics and query-writing ability.
To help you get interview-ready, we’ve compiled a list of the most common SQL interview questions for freshers—along with simple, easy-to-understand answers. And if you want to build confidence with hands-on practice and expert guidance, Palium Skills’ SQL Training & Certification program is the perfect place to start, with classroom and live online training led by industry professionals.
Basic SQL Interview Questions for Freshers
1. What is SQL?
Answer: SQL (Structured Query Language) is a programming language used to communicate with relational databases. It helps in storing, retrieving, and manipulating data.
2. What is a Primary Key?
Answer: A Primary Key is a column (or set of columns) that uniquely identifies each row in a table. It cannot contain NULL values.
3. What is a Foreign Key?
Answer: A Foreign Key is a column that creates a relationship between two tables. It links one table’s primary key to another table.
4. What are SQL Joins?
Answer: Joins are used to combine rows from two or more tables:
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INNER JOIN – Returns matching records from both tables.
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LEFT JOIN – Returns all records from the left table and matching from the right.
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RIGHT JOIN – Returns all records from the right table and matching from the left.
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FULL JOIN – Returns all records when there is a match in either table.
5. What is the difference between WHERE and HAVING?
Answer:
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WHERE is used to filter rows before grouping.
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HAVING is used to filter rows after grouping (with aggregate functions like COUNT, SUM, etc.).
Intermediate SQL Questions for Freshers
6. What is the difference between DELETE, TRUNCATE, and DROP?
Answer:
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DELETE – Removes rows from a table (can use conditions).
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TRUNCATE – Removes all rows, but keeps the table structure.
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DROP – Deletes the table completely.
7. What is a View in SQL?
Answer: A View is a virtual table created from the result of a query. It does not store data physically but allows easy access to stored queries.
8. What are Aggregate Functions?
Answer: Aggregate functions perform calculations on multiple rows and return a single result. Examples:
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COUNT()
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SUM()
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AVG()
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MAX()
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MIN()
9. What is Normalization?
Answer: Normalization is the process of organizing data in a database to reduce redundancy and improve efficiency. It is done in steps called Normal Forms (1NF, 2NF, 3NF, etc.).
10. What is the difference between CHAR and VARCHAR?
Answer:
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CHAR stores fixed-length data.
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VARCHAR stores variable-length data.
Advanced SQL Questions for Freshers
11. What is an Index in SQL?
Answer: An Index improves query performance by making data retrieval faster. It works like an index in a book.
12. What is a Stored Procedure?
Answer: A Stored Procedure is a set of SQL statements saved in the database that can be reused multiple times.
13. What is a Trigger?
Answer: A Trigger is an automatic action executed in response to certain events (INSERT, UPDATE, DELETE) on a table.
14. What is the difference between SQL and NoSQL?
Answer:
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SQL – Works with structured data in relational databases.
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NoSQL – Works with unstructured or semi-structured data (MongoDB, Cassandra, etc.).
15. Write a SQL query to find the second highest salary from an employee table.
Answer:
SELECT MAX(salary)
FROM employees
WHERE salary < (SELECT MAX(salary) FROM employees);
Why Choose Palium Skills for SQL Interview Preparation?
At Palium Skills, we don’t just teach SQL—we prepare you for real-world job success.
✅ Interview-Focused Curriculum – Covers the most commonly asked SQL interview questions.
✅ Hands-On Practice – Solve real case studies and assignments.
✅ Expert Faculty – Trainers with industry hiring experience.
✅ Flexible Learning Options – Classroom training in Kolkata + live online classes across India.
✅ Placement Guidance – Resume tips, mock interviews, and confidence-building sessions.
Conclusion
For freshers, SQL is often the first step into the IT and data analytics industry. Mastering SQL interview questions can give you the confidence to crack job interviews and land your dream role.
At Palium Skills, our SQL Training & Certification program equips you with the right mix of theory, practical exposure, and interview readiness.
👉 Call us today at +91-8420594969 / 7044871915 or visit PaliumSkills.com to enroll in our SQL course and get job-ready!
