Do I need advanced SQL to attempt this?

This problem is labeled as Advanced. 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

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
customerid
transactionid
transactiondate

18. The First Transaction Initiative

Find the very first recorded purchase for every galactic customer.

The galactic accounting department at Zlacksys 19 needs to identify the first transaction made by each customer. Write a query to display each customer's first transaction based on the transaction 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.

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