Clone Order Detector :Find Duplicate Customer Orders by Timestamp and Amount Advanced
Identify duplicate orders by customer, timestamp, and total amount.
Xorthax suspects duplicate orders. Find every order that shares its customer ID, order timestamp, and total amount with at least one other order. Show all matching orders, ordered by customer ID and then order ID.
Write Your Query
This reflects identifying duplicate transactions or billing errors to maintain data accuracy and improve reporting quality.
You’ll practice grouping data by multiple columns, detecting redundant records, and filtering to reveal true duplicates.
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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