Rolling Retention and Drop-Off | Dataford Interview Questions

Your question is Rolling Retention and Drop-Off. Start with the requirements and the two tables on the right.

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Problem

Intuit wants to evaluate user retention and identify where customers drop out of a product funnel. Write a PostgreSQL query using the users and product_events tables.

Requirements

Group users by the month of signup_date.
Calculate rolling retention rates for activity within 7, 14, and 30 days after signup. Use the signup cohort as the denominator.
For each cohort, report users reaching connect_account, create_budget, and view_insights within 30 days.
Calculate each funnel step's conversion rate from the cohort and its drop-off rate from the immediately preceding step. Return the largest drop-off steps first within each cohort.

Schema

users

Column	Type	Description
user_idPK	INT	Unique user identifier
signup_date	DATE	Date the user signed up
acquisition_channel	VARCHAR(30)	Marketing channel associated with signup

product_events

Column	Type	Description
event_idPK	INT	Unique product event identifier
user_id	INT	User associated with the event
event_name	VARCHAR(50)	Name of the product event
occurred_at	TIMESTAMP	Timestamp when the event occurred