SQL Top Categories by Region | Dataford Interview Questions

Samsung Electronics America wants to identify the strongest product categories in each sales region. Write a SQL query to find the top three categories by units sold during the previous completed calendar quarter.

Output

One row per included region and product category, with columns region, category, total_units_sold, and category_rank.
Include only non-null regions and categories with sales in the previous completed calendar quarter. Exclude sales that cannot be matched to a product.
Rank categories within each region by total units sold in descending order, breaking ties alphabetically by category. Return up to three categories per region.
Order the final results by region, category rank, and category.

Schema

sales_transactions

Column	Type	Description
sale_idPK	INT	Unique sales transaction identifier
product_id	INT	Product sold in the transaction
region	VARCHAR(50)	Samsung Electronics America sales region
quantity	INT	Number of units sold
sale_date	DATE	Date of the sale

products

Column	Type	Description
product_idPK	INT	Unique product identifier
product_name	VARCHAR(100)	Samsung product name
category	VARCHAR(50)	Product category used for reporting

Your question is SQL Top Categories by Region. Start with the requirements and the two tables in the Question tab.

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