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CTE for Top Products by Revenue
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CTE for Top Products by Revenue

MediumSQL · PostgreSQL

Problem

Write a query using a CTE to identify the top three products by revenue per category.

Use the provided product and order item data. Revenue is the sum of quantity multiplied by unit price. Break revenue ties by the smaller product ID.

Output

  1. One row per qualifying product, with category, product_id, product_name, revenue, and product_rank.
  2. Include only the top three products in each category, ordered by category and rank.

Schema

products
ColumnTypeDescription
product_idPKINTUnique product identifier
categoryVARCHAR(100)Product category
product_nameVARCHAR(150)Product display name
order_items
ColumnTypeDescription
order_item_idPKINTUnique order item identifier
product_idINTProduct purchased in the order item
quantityINTNumber of units purchased
unit_priceNUMERIC(10,2)Price per unit at purchase time
Tablesproductsorder_items
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Your question is CTE for Top Products by Revenue. Start with the requirements and the two tables in the Question tab.

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