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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
customerid
species
orderdate
totalamount
next_species_order_amount

56. Species Spending, Shift by Shift

Show each customer's total order amount and that of the next same-species customer.

Xorthax wants to analyze spending patterns across different species. Write a query to display each customer's total order amount and the total order amount of the next customer from the same species, based on 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.

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