Payments come from the chain rather than from a row written when the payment happened — if it settled, you will be told, even if this application was restarting at the time.
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Sui’s event log carries a checkpoint, a digest and an index — but no timestamp, and neither does the transaction or its effects. Rather than stamp payments with the moment this page read them and sort on that, they are ordered by checkpoint, which is exact. An invented time would look authoritative and be wrong.