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Trailing 2-order rolling average per customer

foundation · sql🔒Walkthroughs

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Trailing 2-order rolling average per customer

For each PAID order per customer in time order, return the average amount_usd of the current order and the PRIOR one. The very first order per customer gets the average of just itself (window naturally shrinks at the partition start).

Round to 2 decimals.

Columns: customer_id, order_id, order_ts::DATE AS order_date, amount_usd, ma2. Sort by customer_id then order_ts ascending.

Tables & sample data

orders

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query.sql

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