The First Transaction Initiative :Find Each Customer’s Earliest Recorded Transaction Date Advanced
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 reflects tracking when customers first made a purchase to study onboarding, loyalty, or sales trends over time.
You’ll practice identifying first occurrences, organizing time-based data, and filtering for earliest records within groups.
This problem is labeled as Advanced. It’s intended for learners who are already comfortable with common window functions and want to push into more complex analytical patterns. Don’t rush — work through the hints one at a time and study the final query structure carefully.
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