Verify Commit ID Uniqueness

An easy SQL mock interview question on DataDriven, with an AI interviewer who asks follow-up questions and a hire or no-hire decision at the end.

Domain
SQL
Difficulty
easy
Seniority
L3

Interview Prompt

The commit log holds one row per commit along with the author's name. Show the total number of commits next to how many different people authored them.

Summary

Duplicate commit IDs. Are there any?

How This Interview Works

  1. Read the vague prompt (just like a real interview)
  2. Ask clarifying questions to the AI interviewer
  3. Write and run your SQL against a real database
  4. Answer the interviewer's follow-up questions, then get a hire or no-hire decision