Rooms in Common
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
We map user networks through our chat channels: two people count as connected the moment they've both posted in the same channel, no matter how many channels they end up sharing. For each sender, find how many other people they're connected to, most-connected first.
Summary
Two people, one channel, a connection you never counted.
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