The First Door

A medium 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
medium
Seniority
L3

Interview Prompt

Product analytics wants to know how each user first touched the app. From `app_event_deliveries`, return one row per user with their `user_id` and the name of their earliest event as `first_event`.

Summary

The first interaction matters most. Or does 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 and run your SQL against a real database
  4. Answer the interviewer's follow-up questions, then get a hire or no-hire decision