SQL Top Categories by Quarter | Dataford Interview Questions

Write a SQL query to find the top three performing product categories by sales volume for each quarter at Decision Point.

Use the sales, products, and product_categories tables. Sales volume is the sum of quantity for sales with valid dates and products assigned to a category.

Output

One row per returned category and quarter.
Columns: quarter_start, category_name, sales_volume.
Return no more than three categories per quarter, ordered by quarter, sales volume descending, and category name ascending to break ties.

Schema

product_categories

Column	Type	Description
category_idPK	INT	Unique product category identifier
category_name	VARCHAR(100)	Product category name
description	VARCHAR(255)	Optional category description

products

Column	Type	Description
product_idPK	INT	Unique product identifier
product_name	VARCHAR(150)	Product name
category_id	INT	Referenced product category

sales

Column	Type	Description
sale_idPK	INT	Unique sale identifier
product_id	INT	Referenced product
sale_date	DATE	Date of the sale
quantity	INT	Number of units sold

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Problem