Which query gives the row number based on salary for each department? You need to assign a row number.

The query uses the ROW_NUMBER() window function to generate a sequential number for each row within a department, ordered by salary. A typical solution looks like this:

SELECT

department,

employee_id,

salary,

ROW_NUMBER() OVER (PARTITION BY department ORDER BY salary DESC) AS salary_rank

FROM employees;

This partitions the result set by department, orders each partition by salary in descending order, and assigns a unique row number starting at 1 for the highest salary. The approach runs in O(n log n) time due to the sort, but modern RDBMS engines optimize window functions efficiently. If you want to treat ties specially, replace ROW_NUMBER() with RANK() or DENSE_RANK().