This test evaluates a candidate's ability to write and understand SQL queries. The focus is on practical query writing, covering key concepts like data retrieval, filtering, joins, aggregation, and data manipulation (INSERT, UPDATE, DELETE). Candidates will be presented with scenarios based on real-world data structures, and they must write efficient SQL queries to solve the given problems.
Example Question:
+---------+------------+--------+
| sale_id | department | amount |
+---------+------------+--------+
| 1 | Electronics| 100.50 |
| 2 | Clothing | 75.00 |
| 3 | Electronics| 200.00 |
| 4 | Home Goods | 150.75 |
| 5 | Clothing | 50.25 |
| 6 | Electronics| 120.00 |
| 7 | Home Goods | 80.50 |
| 8 | Electronics| 300.00 |
| 9 | Clothing | 125.50 |
| 10 | Home Goods | 90.00 |
+---------+------------+--------+