Normalization Tradeoffs in Practice
A hard SQL mock interview question on DataDriven, with an AI interviewer who asks follow-up questions and a hire or no-hire decision at the end.
- Domain
- SQL
- Difficulty
- hard
- Seniority
- L5
Interview Prompt
The finance team needs total revenue per product category, where a transaction's revenue is the quantity sold times the product's listed price. Return each category with its revenue.
Summary
Clean data or fast queries? You can't always have both.
How This Interview Works
- Read the vague prompt (just like a real interview)
- Ask clarifying questions to the AI interviewer
- Write and run your SQL against a real database
- Answer the interviewer's follow-up questions, then get a hire or no-hire decision