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Problem
Employees With No Salary
Easy- sql
Return the employees who have no salary on record, meaning salary is NULL. A salary of 0 is a salary, so it does not count here.
Expected columns: all four columns of Employees (id, name, dept, salary), in that order. Row order does not matter.
- Input
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
id | name | dept | salary 4 | Dave | IT | NULL- Explanation
Dave is the only employee whose salary is missing.
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
Run your query and check the rows against what the question asks for. Then open the model answer to compare.
SQL
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