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Write a query to generate the specified output using advanced SQL skills with joins, aggregations, and window functions.

SQLhard0.4 min readPremium
Frequency
Low
Asked at 1 company
Category
487
questions in SQL
Difficulty Split
130E|271M|86H
in this category
Total Bank
1,863
across 7 categories
Asked at these companies
Carelon
Key Concepts Tested
joinpartitionsqlwindow
Expert AnswerPremium
81 wordsInterview-ready
Example combining joins, aggregations, windows: WITH base AS (SELECT r.region, p.product, SUM(s.amount) amt FROM sales s JOIN regions r ON s.region_id = r.id JOIN products p ON s.product_id = p.id GROUP BY r.region, p.product), ranked AS (SELECT *, ROW_NUMBER() OVER (PARTITION BY region ORDER BY amt DESC) rn FROM base) SELECT * FROM ranked WHERE rn <= 5. **Why**: JOINs for dimensions; GROUP BY for aggregates; window for ranking. Adjust to required output....
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