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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
orderdate
previousorderdate

57. Order Histories, One Step Back

List each order along with the date of the previous one placed by the same customer.

Xorthax wants to analyze customers' order patterns by looking at their previous orders. Write a query to display the current order and the previous order date for every customer.

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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