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Matthias J. Sax reassigned KAFKA-10578: --------------------------------------- Assignee: Javier Freire Riobó > Convert KTable to a KStream using the previous value > ---------------------------------------------------- > > Key: KAFKA-10578 > URL: https://issues.apache.org/jira/browse/KAFKA-10578 > Project: Kafka > Issue Type: Improvement > Components: streams > Reporter: Javier Freire Riobó > Assignee: Javier Freire Riobó > Priority: Minor > Labels: kip > > Imagine that we have an entity for which we want to emit the difference > between the current and the previous state. The simplest case would be that > the entity was an integer number and you want to emit the subtraction between > the current and previous values. > For example, for the input stream 4, 6, 3 the output 4 (4 - 0), 2 (6 - 4), -3 > (3 - 6) is expected. > The way to achieve this with kafka streams would be through an aggregate. > The main problem, apart from needing more code, is that if the same event is > received twice at the same time and the commit time is not 0, the difference > is deleted and nothing is emitted. > KIP-675: > [https://cwiki.apache.org/confluence/display/KAFKA/KIP-675%3A+Convert+KTable+to+a+KStream+using+the+previous+value] -- This message was sent by Atlassian Jira (v8.3.4#803005)