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Top 10 Performance Query
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Top 10 Performance Query

MediumSQL · PostgreSQL

Problem

Write a SQL query to extract the top 10 performing products.

Use the provided product and sales data. Treat completed sales as valid performance activity and include products without completed sales when determining the ranking.

Output

  1. Return one row per product with product_id, product_name, total_revenue, and total_units.
  2. Return the 10 highest-performing products, ordered by total_revenue descending, then product_id ascending to break ties.

Schema

products
ColumnTypeDescription
product_idPKINTUnique product identifier
product_nameVARCHAR(100)Product name
categoryVARCHAR(50)Product category
product_sales
ColumnTypeDescription
sale_idPKINTUnique sale identifier
product_idINTProduct associated with the sale
quantityINTNumber of units sold
sale_amountDECIMAL(12,2)Revenue generated by the sale
statusVARCHAR(20)Sale status
Tablesproductsproduct_sales
Interviewer

Your question is Top 10 Performance Query. Start with the requirements and the two tables in the Question tab.

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