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SUM, AVG, MIN, MAX
Calculate salary statistics for all employees: total_payroll (SUM), avg_salary (AVG, rounded to nearest dollar), highest_salary (MAX), lowest_salary (MIN), and salary_spread (MAX minus MIN).
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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: One row with 5 salary statistics
Hint
All aggregate functions work on a column: SUM(salary), AVG(salary), MAX(salary), MIN(salary). ROUND(AVG(salary), 0) rounds to whole number.
Concepts
SELECT Aggregation ROUND
Practise the topic: SQL practice questions · GROUP BY exercises
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