SELECT department_id, employee_id, salary, MAX(salary) OVER (PARTITION BY department_id) AS max_salary FROM employees. Or with RANK: SELECT * FROM (SELECT *, RANK() OVER (PARTITION BY department_id ORDER BY salary DESC) r FROM employees) WHERE r = 1. **Why window**: Avoid...
This medium-level SQL question appears frequently in data engineering interviews at companies like Morgan Stanley. While less common, it tests deeper understanding that distinguishes strong candidates. Mastering the underlying concepts (partition, sql, window) will help you answer variations of this question confidently.
Break this problem into components. Identify the core trade-offs involved, then walk the interviewer through your reasoning step by step. Demonstrate awareness of edge cases and production considerations - this is what separates good answers from great ones.
SELECT department_id, employee_id, salary, MAX(salary) OVER (PARTITION BY department_id) AS max_salary FROM employees. Or with RANK: SELECT FROM (SELECT , RANK() OVER (PARTITION BY department_id ORDER BY salary DESC) r FROM employees) WHERE r = 1. Why window: Avoid correlated subquery; single pass. Trade-off: MAX returns all rows with max; RANK returns only top row(s).
Want feedback on your answer?
Paste your answer to this question and our AI Coach scores it, finds gaps, and shows you the FAANG-level version.
Get the most asked SQL questions with expert answers. Instant download.
No spam. Unsubscribe anytime.
Paste your answer and get instant AI feedback with a FAANG-level improved version.
Analyze My Answer — FreeAccording to DataEngPrep.tech, this is one of the most frequently asked SQL interview questions, reported at 1 company. DataEngPrep.tech maintains a curated database of 1,863+ real data engineering interview questions across 7 categories, verified by industry professionals.