SQL for MAU Droplet Behavior | Dataford Interview Questions

Write a SQL query to find the monthly active users (MAU) who spun up a new Droplet but did not configure a managed database within their first 30 days on DigitalOcean.

Use the provided DigitalOcean user, Droplet, and managed database records. Treat the first Droplet creation as the start of the 30-day eligibility period.

Output

One row per calendar month with at least one qualifying user
Columns: mau_month and mau
Sort by mau_month ascending

Schema

users

Column	Type	Description
user_idPK	INT	DigitalOcean user identifier
plan_name	VARCHAR(30)	User's DigitalOcean plan

droplets

Column	Type	Description
droplet_idPK	INT	Droplet identifier
user_id	INT	User who created the Droplet
created_at	TIMESTAMP	Droplet creation timestamp
region	VARCHAR(30)	Droplet region

managed_databases

Column	Type	Description
database_idPK	INT	Managed database identifier
user_id	INT	User who configured the managed database
created_at	TIMESTAMP	Managed database configuration timestamp
engine	VARCHAR(20)	Database engine

Your question is SQL for MAU Droplet Behavior. Start with the requirements and the three tables in the Question tab.

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Problem