# Workers Earning Above Department Average

> Earning above the department average.

Canonical URL: <https://datadriven.io/problems/workers_earning_above_department_average>

Domain: SQL · Difficulty: medium · Seniority: L4

## Problem

Inner-join products to transactions on product_id. Per (product_id, product_name), count transactions. Return product_name and transaction_count. Sort by product_id ascending.

## Tables

### products

- product_id INTEGER
- product_name TEXT
- category TEXT
- price REAL
- rating REAL
- in_stock INTEGER

Sample rows (10 of 200):

| product_id | product_name | category | price | rating | in_stock |
| --- | --- | --- | --- | --- | --- |
| 1001 | Basic Device 1X | Books | 17.52 | 2.7 | 1 |
| 1050 | Deluxe Bundle 2X | Clothing | 25.05 | 4.4 | 1 |
| 1099 | Pro Unit 3X | Home & Kitchen | 32.58 | 2.1 | 1 |
| 1148 | Ultra Tool 4X | Collectibles | 40.11 | 3.8 | 1 |
| 1197 | Essential Set 5X | Toys | 47.64 | 1.5 | 1 |
| 1246 | Classic System 6X | Beauty | 0 | 3.2 | 1 |
| 1295 | Smart Gadget 7X | Automotive | 62.7 | 4.9 | 0 |
| 1344 | Eco Kit 8X | Garden | 70.23 | 2.6 | 1 |
| 1393 | Turbo Pack 9X | Music | 77.76 | 4.3 | 0 |
| 1442 | Premium Widget 10X | Electronics | 85.29 | 2 | 1 |

### transactions

- transaction_id INTEGER
- user_id INTEGER
- product_id INTEGER
- quantity INTEGER
- total_amount REAL
- transaction_date TEXT

Sample rows (10 of 200):

| transaction_id | user_id | product_id | quantity | total_amount | transaction_date |
| --- | --- | --- | --- | --- | --- |
| 1067 | 197 | 1001 | 2 | 23.46 | 2026-02-02 |
| 1134 | 294 | 1050 | 3 | 36.93 | 2026-03-03 |
| 1201 | 391 | 1099 | 4 | 50.4 | 2026-04-04 |
| 1268 | 488 | 1148 | 5 | 63.87 | 2026-05-05 |
| 1335 | 585 | 1197 | 0 | 0 | 2026-06-06 |
| 1402 | 682 | 1246 | 2 | 90.81 | 2026-07-07 |
| 1469 | 779 | 1295 | 3 | 104.28 | 2026-08-08 |
| 1536 | 876 | 1344 | 4 | 117.75 | 2026-09-09 |
| 1603 | 973 | 1393 | 5 | -45 | 2026-01-10 |
| 1670 | 1070 | 1442 | 1 | 144.69 | 2026-02-11 |

## Expected output

First 5 of 91 rows:

| product_name | transaction_count |
| --- | --- |
| Basic Device 1X | 3 |
| Deluxe Bundle 2X | 3 |
| Pro Unit 3X | 2 |
| Ultra Tool 4X | 2 |
| Classic System 16X | 1 |

## Related

- [All practice problems](https://datadriven.io/problems)
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