Where the Lights Stay On
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
An SRE team is compiling a reliability leaderboard by region, where a probe's effective hours is its uptime minus a tenth of its latency, and a probe with no recorded latency counts as having zero latency. Total each region's effective hours and surface the three most reliable regions, with equal totals sharing a place.
Summary
The most reliable regions.
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