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Top N Per Group with Window
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Top N Per Group with Window

MediumSQL · PostgreSQL

Problem

Write a SQL query using a window function to find the top three highest-paid employees in each department.

Use the employees and departments tables. Exclude employees without a department or salary, and break salary ties by the lower employee_id.

Output

  1. One row per selected employee, with department_id, department_name, employee_id, employee_name, salary, and salary_rank.
  2. Include up to three employees per department, ordered by department_id, then salary_rank.

Schema

departments
ColumnTypeDescription
department_idPKINTUnique department identifier
department_nameVARCHAR(100)Department name
employees
ColumnTypeDescription
employee_idPKINTUnique employee identifier
employee_nameVARCHAR(100)Employee full name
department_idINTEmployee department identifier
salaryNUMERIC(12,2)Annual employee salary
Tablesemployeesdepartments
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