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The Duplicate Detection Sprint

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
L3

Interview Prompt

Ahead of a CRM migration, the data quality team needs to flag duplicate email addresses. For each email that appears more than once in the user records, show the email, how many times it appears, and the earliest and most recent signup dates.

Summary

Same email, different rows. Spot the repeats.

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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