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Top 3 Categories by Revenue

MediumSQL · PostgreSQL00:00
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Your question is Top 3 Categories by Revenue. Start with the requirements and the two tables on the right.

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Problem

CCC Intelligent Solutions needs a revenue summary for completed transactions processed through CCC ONE. Write a PostgreSQL query that identifies the top three sales categories for calendar year 2025.

Requirements

  1. Join sales to sale_categories using category_id.
  2. Include only sales with status = 'Completed' and a sale_date in 2025.
  3. Calculate revenue as quantity * unit_price, treating NULL quantity or price as zero.
  4. Return the top three categories, ordered by revenue descending. Break revenue ties alphabetically by category name.

Schema

sales
ColumnTypeDescription
sale_idPKINTUnique identifier for the sale
category_idINTReferences sale_categories.category_id
quantityINTNumber of units sold
unit_priceNUMERIC(12,2)Price for one unit
statusVARCHAR(20)Current sale status
sale_dateDATEDate on which the sale occurred
sale_categories
ColumnTypeDescription
category_idPKINTUnique identifier for a sales category
category_nameVARCHAR(50)Name of the CCC ONE sales category
Tablessalessale_categories
Your solutionPostgreSQL
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