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

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. Design the warehouse model that lets analysts compute day-N return rates for any offset they ask for later, without rescanning the raw event stream. Activity is high-volume, so the model has to keep these queries cheap as daily actives grow into the hundreds of millions.

Practice This Problem

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