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SQL, DSA, and Trees/DP
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SQL, DSA, and Trees/DP

MediumSQL · PostgreSQL

Problem

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

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

Schema

interview_topics
ColumnTypeDescription
topic_idPKINTUnique topic identifier
topic_nameVARCHAR(100)Interview topic name
trackVARCHAR(50)Interview track containing the topic
display_orderINTRequired presentation order
interview_questions
ColumnTypeDescription
question_idPKINTUnique question identifier
topic_idINTAssociated topic identifier
question_titleVARCHAR(150)Question title
estimated_minutesINTEstimated completion time
is_activeBOOLEANWhether the question currently counts toward coverage
Tablesinterview_topicsinterview_questions
Interviewer

Your question is SQL, DSA, and Trees/DP. 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.

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