Jia Tao ~ The hints is production ready, we have implements many hints internal for our Flink engine, such as the table hints and query hints.
The `RelBuilder#project` was modified to support hints already, one reason for hints lost is that the projection are dropped for some reason( maybe some optimization), and you should fix it if you wanna keep that. Best, Danny Chan JiaTao Tao <[email protected]> 于2021年5月27日周四 下午4:22写道： > Hi > Indeed, there's some situation will lose hints, like RelBuilder#project, we > just construct a project without hints(ImmutableList.of()), so it will lose > hints too. > IMO, it's not ready for production, so finally, we give up this feature. > Currently, hints occurs some times in the mail list, proves that this is a > common usage, maybe we need to go over this feature again and make it > product ready. > > > Regards! > > Aron Tao > > > Danny Chan <[email protected]> 于2021年5月27日周四 上午11:01写道： > > > Hi ~ > > > > We have interface RelHintsPropagator for hints propagation customization, > > but you may need to modify the code of the rule a little bit. > > > > Best, > > Danny Chan > > > > Taras Ledkov <[email protected]> 于2021年5月26日周三 下午7:26写道： > > > > > Hi, > > > > > > I am trying to figure out how to use hints correctly. > > > > > > My case: > > > I've registered hint for Aggregate node to force expand DISTINCT > > aggregate. > > > Because is some cases plan with DISTINCT aggregate to JOIN cannot be > > > chosen by the cost. > > > > > > I see that different rules treat hints differently. > > > e.g.: > > > - AggregateExpandDistinctAggregatesRule - copy hints of the source node > > > for new aggregate nodes. > > > - AggregateReduceFunctionsRule - create new node and looses the > original > > > hints. > > > > > > Is is correct behavior and am I missing something at the hints/planner > > > logic? > > > > > > -- > > > Taras Ledkov > > > Mail-To: [email protected] > > > > > > > > >
