MySQL Subquery Exercises: Find the name of the employees who are not supervisors

MySQL Subquery: Exercise-12 with Solution

Write a query to find the name (first_name, last_name) of the employees who are not supervisors.

Sample table: employees

Code:

SELECT b.first_name,b.last_name 
FROM employees b 
WHERE NOT EXISTS (SELECT 'X' FROM employees a WHERE a.manager_id = b.employee_id);

Explanation :

MySQL Subquery with EXISTS or NOT EXISTS

If a subquery returns any rows at all, EXISTS subquery is TRUE, and NOT EXISTS subquery is FALSE. For example :

SELECT column1 FROM t1 WHERE EXISTS (SELECT * FROM t2);

Traditionally, an EXISTS subquery starts with SELECT *, but it could begin with SELECT 5 or SELECT column1 or anything at all. MySQL ignores the SELECT list in such a subquery, so it makes no difference.

MySQL Code Editor:

Structure of 'hr' database:

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