Top Marketing Channels in SQL | Dataford Interview Questions

How would you write a SQL query to identify the top-performing marketing channels based on conversion rate over the last 30 days at Selectquote Insurance Services? Use the provided tables and return channels with at least two leads during the period.

Output

One row per qualifying marketing channel with channel_name, total_leads, conversions, conversion_rate, and performance_rank
Include the three highest-ranked channels, with ties retained
Order by performance_rank, then channel_name

Schema

marketing_channels

Column	Type	Description
channel_idPK	INT	Unique marketing channel identifier
channel_name	VARCHAR(100)	Marketing channel name

leads

Column	Type	Description
lead_idPK	INT	Unique lead identifier
channel_id	INT	Marketing channel associated with the lead
created_at	DATE	Date the lead was created
converted_at	DATE	Date the lead converted, or null if it did not convert

Your question is Top Marketing Channels in SQL. 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