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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
longest_gap_days

77. Deserts of Silence

Xorthax wants to measure the barren stretches of time between a customer’s visits.

Xorthax suspects some of his customers take long breaks between orders. For each customer, find the longest amount of time (in days) between two consecutive orders.

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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