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Salary Lead-Lag Gap Within Department
For each employee, show their salary and the gap to the person immediately below and immediately above them in their department's salary ladder. Return: name, department, salary, prev_salary (LAG), next_salary (LEAD), gap_below (salary - prev_salary), gap_above (next_salary - salary). Order by department, salary.
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Schema
employees
| emp_id | name | department | position | salary | hire_date | manager_id | performance_rating |
|---|---|---|---|---|---|---|---|
| 1 | Alice Johnson | Engineering | Senior Developer | 95000 | 2019-03-15 | 5 | 4.5 |
| 2 | Bob Smith | Engineering | Developer | 75000 | 2020-06-01 | 1 | 3.8 |
| 3 | Carol Williams | Marketing | Marketing Manager | 85000 | 2018-09-20 | NULL | 4.2 |
Expected output: Each employee with their salary neighbours and gaps
Hint
Concepts
SELECT Window Functions LAG LEAD PARTITION BY
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