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SQL for Top Categories by Region
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SQL for Top Categories by Region

MediumSQL · PostgreSQL

Problem

Write a query to identify the top three selling product categories for each region in the last fiscal quarter.

Assume fiscal quarters align with calendar quarters and use the last completed quarter relative to CURRENT_DATE. Include completed orders only, and calculate sales as quantity multiplied by unit price.

Output

  1. One row per qualifying region and category, with region, category, total_sales, and category_rank.
  2. Include at most three categories per region. Break revenue ties alphabetically by category.
  3. Order by region, then category_rank, then category.

Schema

orders
ColumnTypeDescription
order_idPKINTUnique order identifier
regionVARCHAR(50)Customer region associated with the order
product_idINTPurchased product identifier
order_dateDATEDate the order was placed
quantityINTNumber of units purchased
unit_priceNUMERIC(10,2)Price per unit at the time of purchase
statusVARCHAR(20)Order fulfillment status
products
ColumnTypeDescription
product_idPKINTUnique product identifier
product_nameVARCHAR(100)Product name
categoryVARCHAR(50)Product category
Tablesordersproducts
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