Top 50+ SQL Interview Questions and Answers for Beginners and Experienced Professionals

Introduction

Did you know that SQL (Structured Query Language) was developed in the 1970s at IBM by a team led by Donald D. Chamberlin and Raymond F. Boyce? Originally known as SEQUEL (Structured English Query Language), SQL was created to manage the vast amounts of data generated by business operations and financial transactions.

Today, SQL is the standard language for managing and manipulating data stored in relational databases. Regardless of your role in operations, data analysis, data engineering, or data science, a basic understanding of SQL is essential. SQL is a powerful tool for querying, manipulating, and transforming data, and it’s used by organizations of all sizes and industries.

In this article, we’ll provide an overview of the essential SQL concepts and syntax, including SELECT statements, joins, functions, constraints, and transactions. We’ll also share 89 real SQL interview questions and provide step-by-step answers to help you prepare for your next SQL interview.

Whether you’re new to SQL or an experienced professional, this article will help you enhance your SQL skills and prepare for a successful interview. So, let’s dive into the basics of SQL and learn about the must-know concepts and techniques that every SQL developer should master.

In the following sections, we’ll cover the basics of SQL, including its syntax, how to use SELECT…