This repository contains my solutions for SQL problems from HackerRank, covering a wide range of database concepts from basic queries to advanced problem-solving techniques.
The goal of this repository is to document my learning journey, improve my SQL skills, and build strong problem-solving abilities for technical interviews and data Analytics roles.
HackerRank-SQL/
│
├── Basic Select
├── Advanced Select
├── Aggregation
├── Basic Join
├── Advanced Join
└── Alternative Queries
Simple queries using SELECT, WHERE, DISTINCT, ORDER BY, and filtering conditions.
More complex filtering using CASE statements, REGEXP, sorting logic, and advanced conditions.
Working with SUM, COUNT, AVG, MIN, MAX, ROUND, TRUNCATE, and GROUP BY operations.
Solving problems using INNER JOIN, LEFT JOIN, RIGHT JOIN, and combining multiple tables.
Complex joins with multiple conditions, self joins, and handling advanced relationship-based queries.
Problems involving PIVOT, recursive logic, tree structures, ranking logic, and other advanced SQL challenges.
This repository helps me:
- Practice SQL daily
- Improve query writing speed and accuracy
- Strengthen problem-solving and logical thinking
- Prepare for coding interviews
- Build a strong portfolio for Data Engineering and BI roles
Some solutions may have multiple approaches depending on the SQL dialect (SQL Server, MySQL, Oracle, etc.), so I may include alternative versions when necessary.
The focus of this repository is not only solving the problem, but also understanding the logic behind each solution.
Alaa Elhariry Computer Science Graduate Aspiring Data Analytics
https://www.linkedin.com/in/alaa-elhariry/
Feel free to explore the solutions.