fonsdant commented on code in PR #15740: URL: https://github.com/apache/kafka/pull/15740#discussion_r1938264883
########## streams/src/main/java/org/apache/kafka/streams/kstream/KStream.java: ########## @@ -685,6 +685,41 @@ <VR> KStream<K, VR> flatMapValues(final ValueMapper<? super V, ? extends Iterabl <VR> KStream<K, VR> flatMapValues(final ValueMapperWithKey<? super K, ? super V, ? extends Iterable<? extends VR>> mapper, final Named named); + /** + * Marking the {@code KStream} as partitioned signals the stream is partitioned as intended, + * and does not require further repartitioning by downstream key changing operations. + * <p> + * Note that {@link KStream#markAsPartitioned()} SHOULD NOT be used with interactive query(IQ) or {@link KStream#join}. + * For reasons that when repartitions happen, records are physically shuffled by a composite key defined in the stateful operation. + * However, if the repartitions were cancelled, records stayed in their original partition by its original key. IQ or joins + * assumes and uses the composite key instead of the original key. Review Comment: @mjsax, about the docs, do you prefer we add it just in the new PR I will create or in a separate one like transform methods? -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: jira-unsubscr...@kafka.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org