Using Data to Solve Problems | Dataford Interview Questions

How did you use data to solve a problem or answer a question?

Demonstrate your answer with a PostgreSQL query using the supplied campaign data. Summarize active campaigns launched between 2025-01-01 and 2025-03-31, including campaigns with no qualifying activity.

Output

One row per qualifying campaign with campaign_id, campaign_name, total_clicks, total_conversions, conversion_rate, and performance_band.
Include all qualifying campaigns, calculate the rate as conversions divided by clicks times 100, and use 0 when clicks are zero.
Sort by conversion_rate descending, then campaign_id ascending.

Schema

campaigns

Column	Type	Description
campaign_idPK	INT	Unique campaign identifier
campaign_name	VARCHAR(100)	Campaign name
status	VARCHAR(20)	Current campaign status
launch_date	DATE	Campaign launch date

campaign_events

Column	Type	Description
event_idPK	INT	Unique event identifier
campaign_id	INT	Referenced campaign
event_type	VARCHAR(30)	Recorded campaign event type
event_date	DATE	Date of the event

Your question is Using Data to Solve Problems. 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