Do I need advanced SQL to attempt this?

This problem is labeled as Intermediate. You don’t need to be an expert, only comfortable with SQL and willing to experiment. If you get stuck, the hints and solution will help you along.

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

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Practice SQL Window Functions | Xorthax's Trading Post

Tables Used

customers

Column	Type
customerid	bigint
name	text
species	text
contactinfo	text
loyaltystatus	text
joindate	text

orders

Column	Type
orderid	bigint
customerid	bigint
orderdate	timestamp without time zone
totalamount	double precision
status	text

transaction

Column	Type
transactionid	bigint
orderid	bigint
customerid	bigint
supplierid	bigint
transactiontype	text
amount	double precision
currencyid	bigint
transactiondate	text
paymentmethod	text
description	text
status	text
createdat	text
updatedat	text

Expected Output

Column
species
lasttransactiondate

47. Species Transaction Wrap-Up

Find the latest transaction date for each species in the galaxy.

Xorthax is curious about the last transaction date for customers of each species. Write a query to display the last transaction date for each species.

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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