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The Crowded Hour

A easy SQL mock interview question on DataDriven. Practice with AI-powered feedback, real code execution, and a hire/no-hire decision.

Domain
SQL
Difficulty
easy
Seniority
L5

Interview Prompt

We run a consumer app and size capacity per device type, so we need each type's busiest moment. Find the session window (from its start to its start plus duration) with the most users active at the same time, and return the device type, that window written as start to end, and the number of users active.

Summary

Every device type has a moment when the room is fullest. Find it.

How This Interview Works

  1. Read the vague prompt (just like a real interview)
  2. Ask clarifying questions to the AI interviewer
  3. Write your sql solution with real code execution
  4. Get instant feedback and a hire/no-hire decision

Related

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