LeetCode SQL Practice - Datasets & Problem Statements

This repository contains datasets and problem statements for 66 popular SQL questions from LeetCode.
The goal is to practice solving SQL problems directly on Microsoft SQL Server using clean sample datasets.

📂 Directory/Folder Structure:

leetcode-sql-practice/
│
├── datasets/
│   ├── leetcode_sql_practice_dataset.sql
│   └── README_DATASETS.md
│
├── questions/
│   ├── Easy/
│   │    ├── 175_combine_two_tables.md
│   │    ├── 176_second_highest_salary.md
│   │    └── ... (easy questions)
│   ├── Medium/
│   │    ├── 177_nth_highest_salary.md
│   │    ├── 534_game_play_analysis_iii.md
│   │    └── ... (medium questions)
│   ├── Hard/
│   │    ├── 1179_reformat_department_table.md
│   │    └── 1212_team_scores_in_football_tournament.md
├── Solutions/
│   ├── Easy/
│   │    ├── 175_combine_two_tables.md
│   │    ├── 176_second_highest_salary.md
│   │    └── ... (easy questions)
│   ├── Medium/
│   │    ├── 177_nth_highest_salary.md
│   │    ├── 534_game_play_analysis_iii.md
│   │    └── ... (medium questions)
│   ├── Hard/
│   │    ├── 1179_reformat_department_table.md
│   │    └── 1212_team_scores_in_football_tournament.md
└── README.md

Topics Covered

• Basic SQL queries
• Aggregations and Group By
• Joins
• Window functions (RANK, DENSE_RANK)
• CTEs (Common Table Expressions)
• Subqueries
• Data Transformation queries
• Advanced SQL Patterns

---

How to Use

1. Clone or download the repository.
2. Open Microsoft SQL Server Management Studio (SSMS).
3. Create a new database (e.g., Leetcode).
4. Load the full dataset :

 USE Leetcode;
 :r datasets/leetcode_sql_practice_dataset.sql