Top Courses by Domain | Dataford Interview Questions

Write a query to find the top three most popular courses per technology domain on Pluralsight based on user engagement metrics.

Use the provided course, domain, and engagement data. Popularity is determined by total minutes watched, with unique learners and course ID used as tie-breakers.

Output

One row per selected course, including technology_domain, course_id, course_title, total_minutes, unique_learners, engagement_events, and popularity_rank.
Include no more than three courses per domain, ordered by domain, rank, and course ID.

Schema

technology_domains

Column	Type	Description
domain_idPK	INT	Unique technology domain identifier
domain_name	VARCHAR(100)	Technology domain name

courses

Column	Type	Description
course_idPK	INT	Unique course identifier
course_title	VARCHAR(200)	Pluralsight course title
domain_id	INT	Technology domain containing the course

course_engagement

Column	Type	Description
engagement_idPK	INT	Unique engagement event identifier
course_id	INT	Course associated with the engagement event
user_id	VARCHAR(50)	Learner identifier, when available
minutes_watched	INT	Minutes watched during the event

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Problem