Product categories
Easy · Online shop database · DISTINCT, SELECT basics
Each product belongs to a category, and most categories hold several products. List every category once.
Return a single column, category, sorted A to Z.
Expected result
| category |
|---|
| Books |
| Electronics |
| Home |
| Sports |
| Stationery |
The online shop tables
customers: 18 rows, first 5 shown
| id | name | city | country | signup_date | phone |
|---|---|---|---|---|---|
| 1 | Ravi Kumar | Bengaluru | India | 2025-01-12 | +91 98450 12345 |
| 2 | Emily Johnson | Austin | USA | 2025-01-25 | +1 512 555 0142 |
| 3 | Hiroshi Sato | Osaka | Japan | 2025-02-08 | NULL |
| 4 | Ana Souza | Sao Paulo | Brazil | 2025-02-19 | +55 11 91234 5678 |
| 5 | Priya Sharma | Mumbai | India | 2025-03-03 | +91 99200 54321 |
order_items: 40 rows, first 5 shown
| id | order_id | product_id | quantity | unit_price |
|---|---|---|---|---|
| 1 | 1 | 1 | 1 | 22.99 |
| 2 | 1 | 9 | 3 | 3.99 |
| 3 | 2 | 4 | 1 | 189 |
| 4 | 2 | 16 | 2 | 15.99 |
| 5 | 3 | 2 | 1 | 89.5 |
orders: 28 rows, first 5 shown
| id | customer_id | order_date | status |
|---|---|---|---|
| 1 | 1 | 2025-02-03 | delivered |
| 2 | 2 | 2025-02-14 | delivered |
| 3 | 3 | 2025-03-01 | delivered |
| 4 | 1 | 2025-03-22 | cancelled |
| 5 | 4 | 2025-04-05 | delivered |
products: 18 rows, first 5 shown
| id | name | category | price | stock |
|---|---|---|---|---|
| 1 | Wireless Mouse | Electronics | 24.99 | 120 |
| 2 | Mechanical Keyboard | Electronics | 89.5 | 45 |
| 3 | USB-C Hub | Electronics | 39 | 80 |
| 4 | Noise Cancelling Headphones | Electronics | 199 | 25 |
| 5 | Intro to Statistics | Books | 48 | 60 |
-- Write your SQL here