SQL, Python, and Excel Projects | Dataford Interview Questions

Tell me about a project where you used SQL, Python, and Excel to analyze marketing data.

For the SQL portion, write a query using the provided campaign and performance data. Calculate campaign-level marketing results for campaigns active during Q1 2025, handling campaigns with no performance records or zero spend.

Output

One row per eligible campaign, including campaigns without performance records.
Return campaign_id, campaign_name, channel, total_spend, total_revenue, total_conversions, conversion_rate, roi, and performance_band.
Sort by total_revenue descending, then campaign_id ascending.

Schema

campaigns

Column	Type	Description
campaign_idPK	INT	Unique campaign identifier
campaign_name	VARCHAR(150)	Campaign name
channel	VARCHAR(50)	Marketing channel
start_date	DATE	Campaign start date
end_date	DATE	Campaign end date, or NULL if ongoing

campaign_performance

Column	Type	Description
performance_idPK	INT	Unique performance record identifier
campaign_id	INT	Referenced campaign
performance_date	DATE	Date of the performance record
spend	NUMERIC(12,2)	Marketing spend
revenue	NUMERIC(12,2)	Attributed revenue
clicks	INT	Recorded clicks
conversions	INT	Recorded conversions

Your question is SQL, Python, and Excel Projects. 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