SQL Practice Portfolio

Actively practicing SQL to prepare for Data Analyst roles.
Focus: Building strong fundamentals, real-world business logic, and clean code.

Progress Summary (as of 30 Jan, 2026)

Platform	Solved / Total	Difficulty Breakdown
HackerRank SQL	57 / 58	Easy: 41 / Medium: 16 / Hard: 1
StrataScratch	2 / ~75 free	Easy: 1 / Medium: 1 / Hard: 0
LeetCode SQL	1 / ~77 free	Easy: 1 / Medium: 0 / Hard: 0
DataLemur	1 / ~53 free	Easy: 1 / Medium: 0 / Hard: 0

Total problems solved: 61

Platform Handles (for verification)

• HackerRank: https://www.hackerrank.com/profile/pallabdey21
• StrataScratch: https://platform.stratascratch.com/user/Rusher0077
• LeetCode: https://leetcode.com/u/bcV4q59RaA/
• DataLemur: https://datalemur.com/profile

Highlighted Problems

These are some of my favorite problems that demonstrate key SQL concepts:

Platform	Difficulty	Problem Title / ID	Key Concepts	Link
StrataScratch	Easy	Salaries Differences (10308)	Joins, Conditional Aggregation (CASE inside MAX/ABS)	Link
HackerRank	Medium	The Pads	String Concatenation, Grouping, LOWER(), COUNT()	Link
HackerRank	Hard	Interviews	Advanced Joins, Grouping, Aggregation	Link
HackerRank	Medium	Print Prime Numbers	Recursion, UNION ALL, GROUP_CONCAT	Link
HackerRank	Medium	SQL Project Planning	CTEs, DATEDIFF, Window Function (LAG), CASE	Link

(More problems will be added as I complete challenging ones)

Repository Structure

sql-practice-portfolio/
├── hackerrank/
│   ├── easy/
│   ├── medium/
│   └── hard/
├── stratascratch/
│   ├── easy/
│   ├── medium/
│   └── hard/
├── leetcode/
│   ├── easy/
│   ├── medium/
│   └── hard/
└── datalemur/
    ├── easy/
    ├── medium/
    └── hard/

Each file includes:

• Title, Discription of the problem and problem ID (for StrataScratch only)
• Clean, formatted solution (PostgreSQL/MySQL style)

Goals

• Master core SQL concepts: joins, window functions, CTEs, aggregation, string/date handling
• Build a verifiable track record of consistent practice
• Prepare for data analyst technical interviews

Thanks for visiting! Feel free to reach out on LinkedIn:

Last updated: 16 Jan, 2026