Yes, it is currently not possible to pipeline SINKs in RisingWave. The existing semantics do not support chaining SINKs directly. However, a workaround suggested involves using CDC from Postgres to create a pipeline from Source -> Sink -> external pg -> CDC table (no op update detected) -> Kafka. This workaround may not guarantee 'if and only if' behavior due to potential delays between PG and Kafka. A future feature to trigger microservices via a push event is being developed, which may provide a better solution for this use case.