Github user xccui commented on the issue: https://github.com/apache/flink/pull/5016 Hi @fhueske, the PR has been updated. During the refactoring, I got two questions. 1. Do you think it's still necessary to allow the watermark strategy to be `null`? 2. Currently, we only provide an `ExistingField` extractor for the rowtime field. Considering that the `TableSource` may be created from an existing `DataStream`, I think we should also provide a corresponding extractor, which automatically reads the timestamp from the `StreamRecord` and set it as a field. What do you think?
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