Hi team, We notice the UPDATE_BEFORE row kind is not dropped and treated as DELETE as in code <https://github.com/apache/flink/blob/master/flink-connectors/flink-connector-elasticsearch-base/src/main/java/org/apache/flink/streaming/connectors/elasticsearch/table/RowElasticsearchSinkFunction.java#L81-L84>. We're aware that this is useful to retract output records in some cases, but we cannot come up with such a scenario, could anyone name a few cases for it.
The other thing we want to do is drop the UPDATE_BEFORE row kind in the ES connector to reduce the sink traffic since almost all of our records are update. In our case, the records are generated by joining with a couple of upsert-kafka data sources. Only primary-key participants in the join condition for all join cases, with some granularity/cardinality fan-out in the middle. We want to know whether it impacts the final result correctness if we drop the records with UPDATE_BEFORE row kind. -- *Best wishes,* *- Kai*
