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SQL for Top Customers
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SQL for Top Customers

MediumSQL · PostgreSQL

Problem

Write a query to extract the top 10 customers based on sales from a database. Use the customer and sales data provided. Include customers with no recorded sales, treating their total as zero.

Output

  1. One row per customer, with customer_id, customer_name, and total_sales.
  2. Include the 10 highest-selling customers, ordered by total_sales descending.
  3. Break ties by customer_id ascending.

Schema

customers
ColumnTypeDescription
customer_idPKINTUnique customer identifier
customer_nameVARCHAR(100)Customer's full name
sales
ColumnTypeDescription
sale_idPKINTUnique sales transaction identifier
customer_idINTCustomer associated with the sale
sales_amountDECIMAL(12,2)Monetary value of the sale
Tablescustomerssales
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Your question is SQL for Top Customers. Start with the requirements and the two tables in the Question tab.

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