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SQL Join and Total Sales
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SQL Join and Total Sales

MediumSQL · PostgreSQL

Problem

Write a SQL query to join two tables and calculate total sales by customer at Kpmg Us. Use the provided customers and sales tables.

Output

  1. One row per customer, including customers with no matching sales.
  2. Return customer_id, customer_name, and total_sales.
  3. Sort by total_sales descending, then customer_name ascending to break ties.

Schema

customers
ColumnTypeDescription
customer_idPKINTUnique customer identifier
customer_nameVARCHAR(100)Customer or account name
regionVARCHAR(50)KPMG US operating region
sales
ColumnTypeDescription
sale_idPKINTUnique sale identifier
customer_idINTCustomer associated with the sale
sale_amountNUMERIC(12,2)Sale amount in US dollars
sale_dateDATEDate the sale was recorded
Tablescustomerssales
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Your question is SQL Join and Total Sales. Start with the requirements and the two tables in the Question tab.

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