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Problem
Employee Count Per Department
Easy- sql
For every department, return its name and the number of employees in it. A department with no employees still appears, with a count of 0.
Expected columns: dept and n (the employee count). Row order does not matter.
- Input
Departments(dept_id, dept) 1 | Sales 2 | IT 3 | HR 4 | Finance Employees(id, name, dept, salary) 1 | Alice | Sales | 50000 2 | Bob | Sales | 60000 3 | Carol | IT | 70000 4 | Dave | IT | NULL 5 | Eve | HR | 55000- Output
dept | n Finance | 0 HR | 1 IT | 2 Sales | 2- Explanation
Finance has no employees but is still listed, with a count of 0.
Sample database
Your query runs in the browser against these tables. Column names are exact.
Departments
- dept_id
- dept
Employees
- id
- name
- dept
- salary
Customers
- customer_id
- name
- city
- signup_date
Products
- product_id
- name
- category
- price
Orders
- order_id
- customer_id
- order_date
- status
OrderItems
- order_id
- product_id
- quantity
Logins
- customer_id
- login_date
Staff
- staff_id
- name
- title
- manager_id
No automatic grading here
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