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Write queries combining Joins and Group By operations.

SQLmedium0.3 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
Expedia
Key Concepts Tested
join
Expert AnswerPremium
56 wordsInterview-ready
SELECT c.country, COUNT(o.id) AS order_count, SUM(o.amount) AS total_revenue FROM orders o JOIN customers c ON o.customer_id = c.id WHERE o.order_date >= '2024-01-01' GROUP BY c.country ORDER BY total_revenue DESC. **Why**: JOINs bring data together; GROUP BY aggregates. Apply WHERE before GROUP BY to reduce rows....
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