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

customers

Column	Type
customerid	bigint
name	text
species	text
contactinfo	text
loyaltystatus	text
joindate	text

orders

Column	Type
orderid	bigint
customerid	bigint
orderdate	timestamp without time zone
totalamount	double precision
status	text

Expected Output

Column
species
customerid
totalspending
percentrank

61. Percent Rank: Species Spending Edition

Calculate each customer's percent rank for spending within their species.

Xorthax wants to rank customers by their total spending within their species as a percentage. Write a query to calculate the percent rank for each customer based on their spending within their species.

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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