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Revenue by Product Category

EasySQL · PostgreSQL00:00
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Your question is Revenue by Product Category. Start with the requirements and the three tables on the right.

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Problem

Chewy's merchandising team needs a category-level view of revenue from the most recently completed quarter. Assume the reporting date is 2025-04-15, so the last quarter is Q4 2024, from 2024-10-01 through 2024-12-31.

Write a PostgreSQL query that calculates revenue by product category.

Requirements

  1. Include only orders with status = 'completed' placed during Q4 2024.
  2. Calculate revenue as quantity * unit_price from order items.
  3. Group results by product category, labeling a missing category as Uncategorized.
  4. Sort categories by total revenue descending, then category name ascending to break ties.

Schema

orders
ColumnTypeDescription
order_idPKINTUnique order identifier
order_dateDATEDate the order was placed
statusVARCHAR(20)Current order status
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
products
ColumnTypeDescription
product_idPKINTUnique product identifier
product_nameVARCHAR(150)Product name
categoryVARCHAR(80)Product merchandising category
Tablesordersorder_itemsproducts
Your solutionPostgreSQL
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