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

orders

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

Expected Output

Column
customerid
orderid
totalamount
averageordervalue

5. Customer Spending, Averaged and Analyzed

Compare every order to the customer's average; no hyperspace math required.

Xorthax wants to understand the spending habits of his intergalactic customers. Calculate the average order value for each Customer ID at his trading post on Zlacksys 19. Include each individual order's ID and total amount value.

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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