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The Faithful Few

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

We track sessions across many devices for a multi-platform product. For each device type, count the users who have only ever used that single device type across all of their sessions, and return the device type with that exclusive user count.

Summary

Loyal to one platform only.

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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