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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
- L5
Interview Prompt
Our ad platform and our ops alerting system share no common key, only a wall clock: line up each alert with the ad impressions that landed in the same hour. For each campaign, report how many alerts it drew and how many of those were marked resolved, most alerts first.
Summary
No shared key, only a shared clock.
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