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The Churn Predictor

Mission brief

Challenge Briefing

Hard

Aggregation
CTEs
LEFT JOIN
Math

A subscription-based app is seeing its user engagement drop. The Product team needs to identify "Churning Users"—those who were very active last month but have almost stopped logging in this month. Your mission is to find the user IDs whose activity has plummeted between October and November 2023.

The Churn Predictor

Identify users with a significant drop in activity between two months.

The Narrative

Schema Diagram

logins

user_idINT

login_dateDATE

Challenge a Friend

One SQL table. One SQL condition.
Still tricky for most developers.

SQL Editor

Terminal Output

Initializing Database Engine v1.8.0...

Write a SQL query, then click Run Query

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