SQL, DSA, and Trees/DP | Dataford Interview Questions

How would you approach a data engineering interview that includes SQL and data modeling, plus DSA focused on linked lists, trees, and dynamic programming?

For the SQL and data-modeling portion, use the provided relational model to summarize topic coverage across the listed interview areas.

Output

Return one row per topic, including topics with no active questions.
Return topic_name, track, active_question_count, avg_minutes, and readiness.
Count only active questions, replace missing averages with 0.0, and order by the topic display order.

Output details

Round the average active-question estimated_minutes to one decimal place, ignoring NULL values, and use 0.0 when no average exists.
Set readiness to Not started for zero active questions, In progress for one, and Ready for at least two.
Order rows by ascending display_order.

Schema

interview_topics

Column	Type	Description
topic_idPK	INT	Unique topic identifier
topic_name	VARCHAR(100)	Interview topic name
track	VARCHAR(50)	Interview track containing the topic
display_order	INT	Required presentation order

interview_questions

Column	Type	Description
question_idPK	INT	Unique question identifier
topic_id	INT	Associated topic identifier
question_title	VARCHAR(150)	Question title
estimated_minutes	INT	Estimated completion time
is_active	BOOLEAN	Whether the question currently counts toward coverage

Your question is SQL, DSA, and Trees/DP. Start with the requirements and the two tables in the Question tab.

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Problem