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Department Salary Percentile Buckets
Assign each employee a salary percentile bucket within their department using NTILE(4). Show name, department, salary, dept_quartile (1=bottom 25%, 4=top 25%), and a label: 'Bottom 25%', 'Below Median', 'Above Median', 'Top 25%'. Sort by department, salary DESC. NTILE + CASE labeling is a common Amazon and Meta pattern for segmentation.
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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: dept_quartile: 4, label: Top 25%
Hint
Concepts
SELECT Window Functions NTILE PARTITION BY CASE
Practise the topic: SQL practice questions · Window function practice · CASE WHEN practice · Ranking function practice · Advanced SQL interview questions
In these company practice sets
Amazon · Anthropic · Google · Meta · NVIDIA · OpenAI · Snowflake
A SQL Quest challenge matched to patterns reported for these companies — not a question any of them has published.
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