New vs Returning User Share
A hard SQL mock interview question on DataDriven. Practice with AI-powered feedback, real code execution, and a hire/no-hire decision.
- Domain
- SQL
- Difficulty
- hard
- Seniority
- L4
Interview Prompt
A user is 'new' in the month of their very first event in event_data; in every subsequent month they are 'returning'. For each month, compute the ratio of new users and returning users to total active users. Return the month, new user ratio, and returning user ratio.
Summary
Fresh faces versus familiar ones.
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