Code reviewHardcr-g638

Subject Sql join correctnessLevel Mid–Senior~25 minCommon in Databases & SQL · Distributed systems · Code quality & review interviewsIndustries Software development

Question

Review this SQL that reports revenue per customer.

Each order has multiple payments and each customer has many orders.

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Code to reviewsql

1SELECT c.id,2       c.name,3       SUM(o.amount)      AS revenue,4       COUNT(p.id)        AS payment_count5FROM customers c6JOIN orders   o ON o.customer_id = c.id7JOIN payments p ON p.customer_id = c.id8WHERE o.created_at >= '2026-01-01'9GROUP BY c.id, c.name;

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