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.

Will I get hints and step-by-step explanations if I get stuck?

Yes. Every problem comes with optional hints you can reveal one at a time, plus a fully worked step-by-step solution. Hints and solutions will link to Learning Pages where you can get more information about particular concepts. You decide how much help you want while practicing.

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
orderdate
totalamount
maxorderamount

10. The Galactic Max Order Hunt

Discover each customer's largest single order; sorted by time.

Xorthax is curious about the largest single order placed by each of his intergalactic customers. Write a query to calculate the maximum order amount for each customer, ordered by the order date.

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.

All problems on PracticeWindowFunctions.com are completely free and can be solved without creating an account. Right now there are over 80 practice problems, with new ones added regularly.

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