LeetCode Problem Solving - Module 7

In this video, I walk through 5 common LeetCode and SQL interview problems and break them down step-by-step. I explain not just how to solve each one, but also the underlying patterns and thinking behind the solutions—like hashing for grouping, SQL joins, aggregation, and self-joins. Problems covered: Group Anagrams (hash map + canonicalization) Duplicate Emails (GROUP BY + HAVING) Combine Two Tables (LEFT JOIN) Employees Earning More Than Managers (self-join) Customers Who Never Order (anti-join pattern)