Shared Category Purchasers
A medium SQL mock interview question on DataDriven. Practice with AI-powered feedback, real code execution, and a hire/no-hire decision.
- Domain
- SQL
- Difficulty
- medium
- Seniority
- L4
Interview Prompt
The recommendations team is building a collaborative filtering feature and needs to identify users with overlapping purchase interests. For each product category, find pairs of users who both purchased in that category, showing the category, both user IDs, and how many products they share, with the highest overlap first.
Summary
They bought different things from the same aisle.
How This Interview Works
- Read the vague prompt (just like a real interview)
- Ask clarifying questions to the AI interviewer
- Write your sql solution with real code execution
- Get instant feedback and a hire/no-hire decision