The Session Stitcher

A hard SQL interview practice problem on DataDriven. Write and execute real sql code with instant grading.

Domain

SQL

Difficulty

hard

Seniority

L5

Problem

Our event pipeline doesn't track sessions natively. Given a stream of page-view events with user_id and timestamp, define a session as a sequence where no two consecutive events are more than 30 minutes apart. Assign a session_id to each event, then compute the average session duration and average pages per session.

Summary

Page views without sessions are just noise.

Practice This Problem

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