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Guozhang Wang commented on KAFKA-14748: --------------------------------------- [~aki] Thanks for picking this series! I think we can have a light KIP just to summarize: 1. All the operator behavioral changes among these JIRAs. 2. Why we do not make it an opt-in; and therefore: 3. For users who still want the old behavior, what should they change in their code. > Relax non-null FK left-join requirement > --------------------------------------- > > Key: KAFKA-14748 > URL: https://issues.apache.org/jira/browse/KAFKA-14748 > Project: Kafka > Issue Type: Improvement > Components: streams > Reporter: Matthias J. Sax > Assignee: Florin Akermann > Priority: Major > > Kafka Streams enforces a strict non-null-key policy in the DSL across all > key-dependent operations (like aggregations and joins). > This also applies to FK-joins, in particular to the ForeignKeyExtractor. If > it returns `null`, it's treated as invalid. For left-joins, it might make > sense to still accept a `null`, and add the left-hand record with an empty > right-hand-side to the result. -- This message was sent by Atlassian Jira (v8.20.10#820010)