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A medium Data Modeling interview practice problem on DataDriven. Write and execute real data modeling code with instant feedback.

Domain

Data Modeling

Difficulty

medium

Seniority

mid

Problem

We run a short-video social platform and the growth team wants to track how many new users come back on each day after they sign up, broken down by signup cohort and acquisition channel, along with how heavily those returners engage on each day they show up (sessions, videos watched, watch time). Design the warehouse model that lets analysts compute day-N return rates for any offset they ask for later, plus that per-day engagement, without rescanning the raw event stream. Activity is high-volume, so the model has to keep these queries cheap even as the daily activity table grows into the billions of rows.

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Solve this Data Modeling problem with real code execution. DataDriven runs your solution and checks it automatically.