Leetcode SQL codes are shown here
| # | Title | Solution | Difficulty | Note |
|---|---|---|---|---|
| 175 | Combine two tables | MySQL | Easy | |
| 176 | Second Highest Salary | MySQL | Easy | Distinct |
| 177 | Nth Highest Salary | MySQL | Medium | Function |
| 178 | Rank Scores | MySQL | Medium | |
| 180 | Consecutive Numbers | MySQL | Medium | Same table, mulitple joins |
| 181 | Employees Earning More Than Their Managers | MySQL | Easy | |
| 182 | Duplicate Emails | MySQL | Easy | |
| 183 | Customers Who Never Order | MySQL | Easy | |
| 184 | Department Highest Salary | MySQL | Medium | DepartmentId is the key |
| 185 | Department Top Three Salaries | MySQL | Hard | "Count" mindset |
| 196 | Delete Duplicate Emails | MySQL | Easy | |
| 197 | Rising Temperature | MySQL | Easy | DATEDIFF |
| 262 | Trips and Users | MySQL | Hard | |
| 511 | Game Play Analysis I | MySQL | Easy |