Analyze Quarterly Sign-Up Trends | Dataford Interview Questions

Quizlet wants to review sign-up trends by acquisition source for the most recently completed calendar quarter. Write a PostgreSQL query that reports monthly sign-up counts for every acquisition source, including sources with no sign-ups.

Output

One row per month and acquisition source for April through June 2026.
Columns: signup_month, acquisition_source, and signup_count.
Include zero-count month and source combinations.
Sort chronologically by month, then alphabetically by acquisition source.

Schema

users

Column	Type	Description
user_idPK	INT	Unique Quizlet user identifier
email	VARCHAR(255)	User email address
signed_up_at	TIMESTAMP	Timestamp when the user created an account
source_id	INT	Acquisition source associated with the sign-up

signup_sources

Column	Type	Description
source_idPK	INT	Unique acquisition source identifier
source_name	VARCHAR(100)	Name of the acquisition source

Your question is Analyze Quarterly Sign-Up Trends. Start with the requirements and the two tables in the Question tab.

Run and submit as often as you like. When you're ready, talk me through your approach or go straight to the code.

Problem