The Day-7 Retention Cohort
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
For each weekly signup cohort, compute what percentage of users came back and performed an action on day 7 or later. Show the cohort week, total signups, retained users, and retention rate.
Summary
Day one was promising. Day seven tells the truth.
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