SQL Business Case Studies

A collection of 10 Medium-to-Hard SQL Interview Case Studies based on realistic business scenarios.

Project Overview

This project demonstrates SQL skills commonly required for Data Analyst interviews.

Topics Covered

• SQL Joins
• GROUP BY
• HAVING
• Aggregate Functions
• CASE Statements
• COALESCE
• Window Functions
• ROW_NUMBER()
• DENSE_RANK()
• LAG()
• Date Functions
• Conditional Aggregation
• Derived Tables
• Correlated Subqueries

Database

• Customers
• Products
• Orders
• Order_Items

SQL Dialect

• MySQL 8.0

Project Structure

schema.sql
sample_data.sql
questions.md
solutions.sql

Author

Emmanuel Thomas

Aspiring Data Analyst

Skills:

• SQL
• Python
• Pandas
• Excel
• Power BI