Thanks, i'm fine with that.
Timo Walther <twal...@apache.org> 于2020年9月9日周三 下午7:02写道： > I agree with Jark. It reduces confusion. > > The DataStream API doesn't know changelog processing at all. A > DataStream of Row can be used with both `fromDataStream` and > `fromChangelogStream`. But only the latter API will interpret it as a > changelog something. > > And as I mentioned before, the `toChangelogStream` must work with Row > otherwise users are confused due to duplicate records with a missing > changeflag. > > I will update the FLIP-136 a last time. I hope we can then continue to a > vote. > > Regards, > Timo > > > On 09.09.20 10:50, Danny Chan wrote: > > I think it would bring in much confusion by a different API name just > because the DataStream generic type is different. > > If there are ChangelogMode that only works for Row, can we have a type > check there ? > > > > Switch to a new API name does not really solve the problem well, people > still need to declare the ChangelogMode explicitly, and there are some > confusions: > > > > • Should DataStream of Row type always use #fromChangelogStream ? > > • Does fromChangelogStream works for only INSERT ChangelogMode ? > > > > > > Best, > > Danny Chan > > 在 2020年9月9日 +0800 PM4:21，Timo Walther <twal...@apache.org>，写道： > >> I had this in the inital design, but Jark had concerns at least for the > >> `toChangelogStream(ChangelogMode)` (see earlier discussion). > >> > >> `fromDataStream(dataStream, schema, changelogMode)` would be possible. > >> > >> But in this case I would vote for a symmetric API. If we keep > >> toChangelogStream we should also have a fromChangelogStream. > >> > >> And if we unify `toChangelogStream` and `toDataStream`, retractions > >> cannot be represented for non-Rows and users will experience duplicate > >> records with a missing changeflag. > >> > >> Regards, > >> Timo > >> > >> > >> On 09.09.20 09:31, Danny Chan wrote: > >>> “But I think the planner needs to > >>> know whether the input is insert-only or not.” > >>> > >>> Does fromDataStream(dataStream, schema, changelogMode) > >>> > >>> solve your concerns ? People can pass around whatever ChangelogMode > they like as an optional param. > >>> By default: fromDataStream(dataStream, schema), the ChangelogMode is > INSERT. > >>> > >>> Best, > >>> Danny Chan > >>> 在 2020年9月9日 +0800 PM2:53，dev@flink.apache.org，写道： > >>>> > >>>> But I think the planner needs to > >>>> know whether the input is insert-only or not. > >>> > >> > > > >
