HackerRank SQL (Basics + Intermediate) Certified

Certification Overview

The HackerRank SQL (Basics + Intermediate) Certification validates your ability to write accurate, efficient, and optimized SQL queries. It covers essential topics like SELECT statements, filtering, joins, aggregation, subqueries, and set operations.

This certification reflects proficiency in using SQL for data retrieval and analysis—an essential skill for data science, backend development, and database administration roles.

Skills & Topics Covered

SQL Basics

SELECT, WHERE, ORDER BY
LIMIT, DISTINCT, BETWEEN
Aggregation functions (SUM, COUNT, AVG)

Intermediate SQL

JOINs (INNER, LEFT, RIGHT, FULL)
GROUP BY, HAVING clauses
Subqueries and nested SELECTs

Advanced Filtering

IN, EXISTS, CASE statements
Window functions (ROW_NUMBER, RANK)
NULL handling and pattern matching

My Learning Journey

Learning Phase

Practiced SQL queries daily on HackerRank and W3Schools, progressing from basic to intermediate problems.

Practice Assessments

Completed timed challenges and mock tests to gain speed and accuracy in writing SQL queries.

Final Certification Test

Successfully passed both SQL Basic and Intermediate tests with verified scores on HackerRank.

Key Learnings & Applications

🧩 SQL Fundamentals

Mastered core SQL operations like SELECT, WHERE, ORDER BY, LIMIT, and DISTINCT.

🔗 Joins & Relationships

Gained hands-on experience with INNER, LEFT, RIGHT, and FULL joins to retrieve related data across multiple tables.

📊 Aggregation & Grouping

Learned how to group data and apply functions like COUNT(), AVG(), SUM(), and use GROUP BY and HAVING.

🔍 Subqueries & Filtering

Practiced complex queries using subqueries, IN, BETWEEN, LIKE, EXISTS, and conditional logic with CASE.

Future Applications

This certification has validated my SQL skills, enabling me to:

Write efficient SQL queries to extract, filter, and manipulate data from relational databases.
Support data analysis tasks by joining, grouping, and aggregating data for business insights.
Work with databases like MySQL, PostgreSQL, or Oracle in real-world projects and internships.
Collaborate with backend developers, data analysts, and data engineers on data-intensive applications.
Lay the foundation for advanced database topics like stored procedures, indexing, and optimization.