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Top Customers Revenue SQL
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Top Customers Revenue SQL

MediumSQL · PostgreSQL

Problem

Write a SQL query to find the top five customers by revenue given three tables: orders, customers, and payments.

Treat revenue as the sum of settled payments associated with each customer's orders. Include customers without settled payments as zero revenue.

Output

  1. Return customer_id, customer_name, and revenue, with one row per customer.
  2. Return the five highest-revenue customers, ordered by revenue descending and customer_id ascending to break ties.

Schema

customers
ColumnTypeDescription
customer_idPKINTUnique customer identifier
customer_nameVARCHAR(100)Customer display name
orders
ColumnTypeDescription
order_idPKINTUnique order identifier
customer_idINTCustomer who placed the order
order_dateDATEDate the order was placed
payments
ColumnTypeDescription
payment_idPKINTUnique payment identifier
order_idINTOrder associated with the payment
payment_amountNUMERIC(12,2)Amount recorded for the payment
payment_statusVARCHAR(30)Payment processing status
Tablesorderscustomerspayments
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