Do I need advanced SQL to attempt this?

This problem is labeled as Intermediate. You don’t need to be an expert, only comfortable with SQL and willing to experiment. If you get stuck, the hints and solution will help you along.

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Practice SQL Window Functions | Xorthax's Trading Post

Tables Used

products

Column	Type
productid	bigint
name	text
description	text
category	text
price	double precision
supplierid	bigint
stockquantity	bigint

Expected Output

Column
supplierid
productcount
supplier_num

19. Top Suppliers of the Trade Federation

Rank suppliers by the diversity of products they provide.

Xorthax wants to find the top suppliers in terms of the number of unique products they supply. Assign a row number to each supplier based on the number of unique products supplied, with the highest count ranked first.

Write Your Query

This problem is labeled as Intermediate. You don’t need to be an expert—just comfortable with SQL and willing to experiment. If you get stuck, the hints and solution will guide you step by step.

Yes. Every problem comes with optional hints you can reveal one at a time, plus a fully worked step-by-step solution. You decide how much help you want while practicing.

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