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SQL Query With Joins And Grouping
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SQL Query With Joins And Grouping

MediumSQL · PostgreSQL

Problem

Write a SQL query using GROUP BY, INNER JOIN, and ORDER BY.

Use the provided department and employee tables. Return only departments with at least one matching employee, summarize employee counts and salaries, and sort the results by total salary from highest to lowest.

Output

  1. One row per department
  2. Columns: department_name, employee_count, and total_salary
  3. Exclude departments without employees and employees without a matching department
  4. Sort by total_salary descending, with NULL totals last, then department_name ascending

Schema

departments
ColumnTypeDescription
department_idPKINTUnique department identifier
department_nameVARCHAR(100)Department display name
employees
ColumnTypeDescription
employee_idPKINTUnique employee identifier
employee_nameVARCHAR(100)Employee full name
department_idINTEmployee department reference
salaryDECIMAL(12,2)Annual employee salary
Tablesdepartmentsemployees
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