Activity Histogram

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

Retention modeling suspects the platform has a bimodal usage pattern: a cluster of one-and-done visitors and a cluster of heavy regulars with little in between. Build a histogram of session counts so the team can see how many users fall at each level of activity.

Summary

How many users did X things? Build the distribution.

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