Second highest distinct salary
Your task
Given staff with columns name, team, salary, hired and manager, return the second highest DISTINCT salary as an integer. Return -1 when there is no second distinct value.
Examples
second_salary(staff: dataframe) -> intExample 1
Input
second_salary(staff)staff
More rows not shown
| name | team | salary | hired | manager |
|---|---|---|---|---|
| Ada | eng | 120 | 2021-03-01 | Grace |
| Grace | eng | 150 | 2019-06-15 | NULL |
| Linus | eng | 95 | 2022-01-10 | Grace |
| Mel | sales | 80 | 2020-11-05 | Kay |
| Kay | sales | 110 | 2018-02-20 | NULL |
| Ivan | sales | 80 | 2023-07-01 | Kay |
| Jean | design | 105 | 2021-09-30 | NULL |
| Nia | design | 140 | 2022-05-04 | Jean |
Output
140