When To Use Dense Rank In A Coding Interview?

Identify the second-highest salary in each department. Your output should include the department, the second highest salary, and the employee ID. Do not remove duplicate salaries when ordering salaries. For example, if multiple employees share the same highest salary, the second-highest salary will be the next salary that is lower than the highest salaries.

Sorting and ranking salaries is a common interview task that tests your ability to work with grouped data in Pandas. In this challenge, you’ll need to rank salaries within each department, ensure no gaps using dense ranking, and extract the second-highest salary while keeping duplicates intact.

Approach Hints

To help you think through this problem on your own, here are the technical concepts and steps you can follow:

Sorting the Data

• Sort the dataset by department and salary in descending order.?
• This ensures that the highest salaries appear first within each department.?

Ranking Salaries

• Use the rank() function with method='dense' to rank salaries within each department.?
• This prevents gaps in ranking if duplicate salaries exist.?

Filtering for Rank 2

• Extract only the employees where the rank is 2, representing the second-highest salary.

Selecting Relevant Columns

• Keep only department, employee_id, and salary (renamed as second_highest_salary).

Take the challenge!

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