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SQL Problems

Joins, aggregations, window functions, subqueries, and database query patterns.

📄️ Cinema Seat Allocation

LeetCode 1487 | Difficulty: Medium

📄️ Classes More Than 5 Students

LeetCode Link

📄️ Count Student Number in Departments

LeetCode Link

📄️ Customers Who Never Order

LeetCode 183 | Difficulty: Easy

📄️ Daily Temperatures

LeetCode 739 | Difficulty: Medium

📄️ Delete Duplicate Emails

LeetCode 196 | Difficulty: Easy

📄️ Department Highest Salary

LeetCode 184 | Difficulty: Medium

📄️ Department Top Three Salaries

LeetCode 185 | Difficulty: Hard

📄️ Duplicate Emails

LeetCode 182 | Difficulty: Easy

📄️ Employee Bonus

LeetCode 577 | Difficulty: Easy

📄️ Employees Earning More Than Their Managers

LeetCode 181 | Difficulty: Easy

📄️ Find Customer Referee

LeetCode 584 | Difficulty: Easy

📄️ Maximum Product of Three Numbers

LeetCode 628 | Difficulty: Easy

📄️ Maximum Product of Word Lengths

LeetCode 318 | Difficulty: Medium

📄️ Nth Highest Salary

LeetCode 177 | Difficulty: Medium

📄️ Reorder Data in Log Files

LeetCode 974 | Difficulty: Medium

📄️ Replace Employee ID With The Unique Identifier

LeetCode 1509 | Difficulty: Easy

📄️ Rising Temperature

LeetCode 197 | Difficulty: Easy

📄️ Second Highest Salary

LeetCode 176 | Difficulty: Medium

📄️ Sign of the Product of an Array

LeetCode 1950 | Difficulty: Easy

📄️ Swap Salary

LeetCode Link

📄️ Unique Email Addresses

LeetCode 965 | Difficulty: Easy

📄️ Winning Candidate

LeetCode Link