SQL Exercise: A department 50 employee without a commission %

SQL SORTING and FILTERING on HR Database: Exercise-33 with Solution

33. From the following table, write a SQL query to find those employees who do not have commission percentage and have salaries between 7000, 12000 (Begin and end values are included.) and who are employed in the department number 50. Return all the fields of employees.

Sample table : employees

Sample Solution:

SELECT * 
	FROM employees 
		WHERE commission_pct IS NULL 
			AND salary BETWEEN 7000 AND 12000 
				AND department_id=50;

Sample Output:

employee_id | first_name | last_name | email | phone_number | hire_date | job_id | salary | commission_pct | manager_id | department_id
-------------+------------+-----------+-------+--------------+-----------+--------+--------+----------------+------------+-------------
(0 rows)

Code Explanation:

The said query in SQL that selects all columns (*) from the 'employees' table where the value in the "commission_pct" column is NULL, the value in the "salary" column is between 7000 and 12000, and the value in the "department_id" column is equal to 50. The resulting output will be all the rows from the "employees" table that meet the conditions as stated.

Relational Algebra Expression:

Relational Algebra Tree:

Practice Online

N.B.: In certain instances not null is removed in table structure, so results may vary.

Query Visualization:

Duration:

Rows:

Cost:

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