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If the user has logic that involves actively filtering out idempotent update operations, then they will be able to remove this code in a future release once this KIP has been integrated into Kafka Streams. For now, this KIP will aim to add a minimum number of configurations, and avoid adding APIs. If the user has any logic regarding timestamps, there might be a chance that their program will be affected. This is specific however to the individual user, and behavior will have to be changed accordingly.

Rejected Alternatives

Equality Checking using Object#equals()

We have decided to abandon using equals() to check equality for now. There are concerns that this will not be a good way to reliably compare two values without errors. 

Configuration for Opting Out

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