Species Revenue Leaderboard:Compare Species by Total Revenue to Identify Top-Earning Groups
Intermediate
Find out which species are Xorthax's most valuable patrons by revenue.
The merchants guild of Zlacksys 19 wants to identify the species generating the most revenue for Xorthax. Write a query to rank species based on their total revenue at the trading post.
Write Your Query
Answer:
select c.species,
sum(o.totalamount) as totalrevenue,
dense_rank() over (
order by sum(o.totalamount) desc) as rank
from orders o
join customers c on o.customerid = c.customerid
group by c.species;
Explanation:
It reflects business intelligence reporting where customer groups or demographics are ranked by their contribution to total revenue.
You’ll explore methods for summarizing and ranking grouped data to compare performance across categories.
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.
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