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

suppliers

Column	Type
supplierid	bigint
name	text
originplanet	text
contactinfo	text
rating	double precision

Expected Output

Column
supplierid
suppliername
fifthlargestorder
fifthlargestdate

The Fifth Fulfillment :Find Each Supplier’s Fifth Largest Order Amount and Fulfillment Date Intermediate

Q: Do I need advanced SQL to attempt this?

This problem is labeled as Intermediate. It assumes you’ve written a few window function queries before, but you don’t need to be an expert. Use the hints and explanations if you get stuck — they’re there to help you think through the logic.

Reveal the fifth largest order completed by each supplier including date and amount.

Xorthax wants to find the fifth largest order fulfilled by each supplier. Write a query to display the order amount and date for each supplier.

Write Your Query

Answer:

          with so as
  (select distinct s.supplierid,
                   s.name as suppliername,
                   o.orderid,
                   o.totalamount,
                   o.orderdate
   from orderdetails od
   join orders o on od.orderid = o.orderid
   join products p on od.productid = p.productid
   join suppliers s on p.supplierid = s.supplierid)
select distinct supplierid,
                suppliername,
                NTH_VALUE(totalamount, 5) over (partition by supplierid
                                                order by totalamount desc, orderid desc rows between unbounded PRECEDING and unbounded following) as fifthlargestamount,
                                               NTH_VALUE(orderdate, 5) over (partition by supplierid
                                                                             order by totalamount desc, orderid desc rows between unbounded PRECEDING and unbounded following) as fifthlargestdate
from so
order by suppliername;

This represents supplier performance tracking, helping businesses identify mid-tier high-value transactions within vendor histories.

You’ll practice ranking aggregated order data and extracting specific positions within ordered supplier results.

This problem is labeled as Intermediate. It assumes you’ve written a few window function queries before, but you don’t need to be an expert. Use the hints and explanations if you get stuck — they’re there to help you think through the logic.

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.

SQL for Data Analysis (O’Reilly)

SQL techniques tailored for analytics and reporting workflows.

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Tables Used

Expected Output

The Fifth Fulfillment :Find Each Supplier’s Fifth Largest Order Amount and Fulfillment Date Intermediate

Reveal the fifth largest order completed by each supplier including date and amount.

What real-world scenario does this represent?

What SQL concepts will I practice here?

Do I need advanced SQL to attempt this?

Will I get hints and step-by-step explanations if I get stuck?

Are the problems free to access, and how many are available?

SQL for Data Analysis (O’Reilly)