Hi Xingcan, Thanks for bringing it up for discusson.
I agree with you that we should not deprecate the split/select methods. Their semantics are very clear and they are widely adopted by Flink users. We should fix these problems instead of simply deprecating the methods. Regards, Xiaogang Xingcan Cui <xingc...@gmail.com> 于2019年6月15日周六 下午4:13写道： > Hi all, > > Recently, I noticed that the split/select methods in DataStream API have > been marked as deprecated since 1.7.2 and 1.8.0 (the related JIRA issue > FLINK-11084 <https://issues.apache.org/jira/browse/FLINK-11084>). > > Although the two methods can be replaced by the more powerful side output > feature[1], I still doubt whether we should really remove them in the > future. > > 1. From semantics, the split/select is the reverse operation to the union > transformation. Without them, the DataStream API seems to be missing a > piece. > > 2. From accessibility, the side output only works for process functions, > which means it forces the user to dive into a lower API. > > According to FLINK-11084 < > https://issues.apache.org/jira/browse/FLINK-11084>, there exist some > problems with the current implementation of the two methods. Maybe we > should fix the problems and re-active them again. Or if they really need to > be deprecated, we should at least mark the corresponding documentation for > that : ) > > What do you think? > > Best, > Xingcan > > [1] > https://ci.apache.org/projects/flink/flink-docs-master/dev/stream/side_output.html > < > https://ci.apache.org/projects/flink/flink-docs-master/dev/stream/side_output.html > >
