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querygym — Top 3 customers by revenue

Problem. Return the top 3 customers by total completed-order revenue.

SELECT c.name,
       ROUND(SUM(oi.quantity*oi.unit_price),2) AS revenue
FROM customers c
JOIN orders o ON o.customer_id=c.customer_id
JOIN order_items oi ON oi.order_id=o.order_id
WHERE o.status='completed'
GROUP BY c.customer_id
ORDER BY revenue DESC, c.customer_id
LIMIT 3;

✓ Correct — 3 rows matched

name	revenue
Grace	1842.60
Priya	1655.18
Tom	1498.04

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