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Total Revenue by Product Category

Question

Calculate total revenue generated by each product category. Return category name and total revenue, highest first.

💡 Join categories, products, and order_items.
SQL Editor
Solution
SELECT
  cat.category_name,
  SUM(oi.quantity * oi.unit_price) AS total_revenue
FROM categories cat
JOIN products p ON cat.category_id = p.category_id
JOIN order_items oi ON p.product_id = oi.product_id
GROUP BY cat.category_id, cat.category_name
ORDER BY total_revenue DESC;
Explanation: Chain three JOINs from categories → products → order_items. Revenue = quantity × unit_price. Group by category.