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An easy 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
- easy
- Seniority
- L3
Interview Prompt
An analyst auditing the board's monthly active users report wants the calendar months in `user_sessions` where someone came back, since raw activity overstates the audience in those months. Show each month's number of different users next to its number of sessions.
Summary
Which months actually had an audience?
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