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SQL Top Products Query

MediumSQL · PostgreSQL00:00
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Your question is SQL Top Products Query. Start with the requirements and the three tables on the right.

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Problem

Business Context

Cloud Software Group's product analytics team wants to identify the strongest-selling products within each product category. Revenue should reflect completed orders only.

Task

Write a PostgreSQL query that returns the top three products by revenue for every product category.

Requirements

  1. Join products, order items, and orders to calculate revenue as quantity * unit_price.
  2. Include only orders with status = 'completed'.
  3. Aggregate revenue by product and category, then rank products independently within each category.
  4. Return products ranked 1 through 3, ordered by category, revenue descending, and product ID as a deterministic tie-breaker.

Schema

products
ColumnTypeDescription
product_idPKINTUnique product identifier
product_nameVARCHAR(100)Product name
categoryVARCHAR(50)Product category
order_items
ColumnTypeDescription
order_item_idPKINTUnique order-line identifier
order_idINTReferences orders.order_id
product_idINTReferences products.product_id
quantityINTNumber of units purchased
unit_priceNUMERIC(10,2)Price per unit at purchase time
orders
ColumnTypeDescription
order_idPKINTUnique order identifier
order_dateDATEDate the order was placed
statusVARCHAR(20)Order lifecycle status
Tablesproductsorder_itemsorders
Your solutionPostgreSQL
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