Data-Science-Coding

This repository is a curated collection of DS and SQL problem solutions I’ve worked on as part of my data science prep. The questions are sourced from popular platforms like HackerRank and StrataScratch, helping me sharpen data querying and analytical thinking.

🔹 HackerRank (MySQL)

Contains SQL questions from HackerRank’s SQL domain especially focused on MySQL.
Topics covered include:

• SELECT statements
• JOIN operations
• Aggregations and GROUP BY
• Subqueries and Window Functions

🛠 Most queries are written in MySQL-compatible SQL but can be adapted to other dialects easily.

🔹 StrataScratch

Includes real-world SQL problems from StrataScratch, often asked in data analyst/data science interviews.
Problems range from beginner to advanced, covering:

• Data cleaning and filtering
• CTEs and subqueries
• Joins and aggregations
• Window functions

🗂 Folder structure

Each file is named after the problem, e.g., select_basics.sql, employee_salarys.sql, etc.

📌 Notes

• This repository is a work in progress, and will continue to grow as I solve more problems.
• All solutions use standard SQL syntax where possible, with a focus on MySQL dialects.
• Useful for interview prep, concept revision and building SQL fluency for data roles.