Hi community:SQL contains aggregate functions, GROUP BY, etc，will generate a RetractStream, which type is DataStream[(Boolean, Row)]. It's not allowed to write to Kafka because kafka table is based on AppendStreamTableSink.
If I only need to write ADD message to Kafka, is it possible to achieve this only by SQL? What is the classical usage for this? tableEnv.toRetractStream[Row](...).filter(_._1).map(_._2).addSink(new KafkaProducer) or How to convert a RetractStream to a DataStream, then use SQL to output to Kafka?
