Overlapping User Sessions

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

L4

Interview Prompt

The user_sessions table records session windows, each with a start time and a duration. Find every pair of overlapping sessions for the same user, where two sessions overlap when each begins before the other finishes, and return the user_id, both session_ids and both start times.

Summary

Two sessions, one user, same clock. Something overlaps.

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