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SQL Top Customers Query

EasySQL · PostgreSQL00:00
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Your question is SQL Top Customers Query. Start with the requirements and the one table on the right.

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Problem

Business Context

Impact Analytics wants to identify its highest-value customers from sales transactions. The result will support prioritization in customer performance reporting.

Task

Write a PostgreSQL query to find the top 5 customers by total sales.

Requirements

  1. Exclude transactions that do not have a customer name.
  2. Calculate total sales for each customer by summing sale_amount.
  3. Return the five customers with the highest totals, sorted from highest to lowest. Use customer name as a secondary ascending sort for deterministic results.

Schema

sales
ColumnTypeDescription
sale_idPKINTUnique transaction identifier
customer_nameVARCHAR(100)Name of the customer associated with the transaction
sale_amountDECIMAL(10,2)Sales amount for the transaction
sale_dateDATEDate on which the transaction occurred
Tablessales
Your solutionPostgreSQL
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