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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
start_date
end_date
slowdown_length

79. The Waning Moon of Commerce

Under certain moons, business dimmed, leaving Xorthax to endure the longest nights of quiet trade.

Xorthax is tracking business slowdowns. Find stretches of consecutive days where the total daily revenue from orders fell below 25,000. From those stretches, return the five longest, making sure ties in length are treated as equally ranked. Show the start date, end date, and streak length, ordered first by streak length and then by start date.

Write Your Query

This problem is labeled as Advanced. 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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