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Guozhang Wang commented on KAFKA-7497: -------------------------------------- [~rmoff] Before we dive into the implementation details, could you list the motivations for self-joins in Streams? Note that since stream-join only support key-based join now, self-join should be well covered by just "enrich" the stream record via `map` etc. > Kafka Streams should support self-join on streams > ------------------------------------------------- > > Key: KAFKA-7497 > URL: https://issues.apache.org/jira/browse/KAFKA-7497 > Project: Kafka > Issue Type: New Feature > Components: streams > Reporter: Robin Moffatt > Priority: Major > Labels: needs-kip > > There are valid reasons to want to join a stream to itself, but Kafka Streams > does not currently support this ({{Invalid topology: Topic foo has already > been registered by another source.}}). To perform the join requires creating > a second stream as a clone of the first, and then doing a join between the > two. This is a clunky workaround and results in unnecessary duplication of > data. -- This message was sent by Atlassian JIRA (v7.6.3#76005)