Basic SELECT statement: Get unique department ID from employee table

MySQL Basic Select Statement: Exercise-2 with Solution

Write a query to get unique department ID from employee table.

Sample table: employees

Code:

SELECT DISTINCT department_id 
	FROM employees;

Relational Algebra Expression:

Relational Algebra Tree:

Pictorial Presentation of the above query

Result :

MySQL Code Editor:

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Previous: Write a query to display the names (first_name, last_name) using alias name "First Name", "Last Name".
Next: Write a query to get the details of all employees according to first name in descending order.