Write a query to fetch unique department names from the departments table.

Objective

Write a query to fetch unique department names from a table named departments.

Step 1: Create departments Table

We’ll first create the table to hold department data:

CREATE TABLE departments (
    id INT PRIMARY KEY,
    department_name VARCHAR(100)
);

Step 2: Insert Dummy Data (with duplicates)

Let’s insert some sample data into the table. We’ll intentionally include duplicate department names:

INSERT INTO departments (id, department_name) VALUES
(1, 'HR'),
(2, 'Engineering'),
(3, 'Sales'),
(4, 'HR'),
(5, 'Engineering'),
(6, 'Marketing'),
(7, 'Finance');

Step 3: SQL Query to Fetch Unique Department Names

Now we want to fetch distinct (unique) department names. Here's the query:

SELECT DISTINCT department_name FROM departments;

Output

The DISTINCT keyword ensures that only unique values are returned — no duplicates.

Summary