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

orderdetails

Column	Type
orderdetailid	bigint
orderid	bigint
productid	bigint
quantity	bigint
unitprice	double precision
currencyid	bigint

orders

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

products

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

Expected Output

Column
category
productname
nextproduct

54. Product Pairs in Category Time

List each product sale and the next item sold in its category by date.

Xorthax is studying sales trends by category. Write a query to display each product sold and the next product sold within the same category, based on 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.

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