Some rules we use `RelBuilder project(Iterable<? extends RexNode> nodes) `, sometimes use `RelBuilder project(Iterable<? extends RexNode> nodes, Iterable<String> fieldNames)`, and this really makes me confused.
Regards! Aron Tao JiaTao Tao <[email protected]> 于2020年10月22日周四 下午4:13写道： > Thanks, Julian > One more question is that I can see many > RelBuilder#project(java.lang.Iterable<? extends > org.apache.calcite.rex.RexNode>, java.lang.Iterable<java.lang.String>) > calling in some rules, does this meets the expect, if we don't want to keep > alias in optimizer. > > > Regards! > > Aron Tao > > > Julian Hyde <[email protected]> 于2020年10月22日周四 下午3:29写道： > >> See my comments in 1584. I think that answers your question. >> >> Julian >> >> > On Oct 21, 2020, at 23:35, JiaTao Tao <[email protected]> wrote: >> > >> > Hi Danny >> > Thanks for your reply, can you explain "Calcite only optimize based on >> the >> > field input refs, if we always keep the alias, there are many cases that >> > can not be promoted" a bit? In my mind, alias just field names, doesn't >> > affect the input refs? >> > >> > Regards! >> > >> > Aron Tao >> > >> > >> > Danny Chan <[email protected]> 于2020年10月22日周四 上午11:29写道： >> > >> >> During planning, Calcite only optimize based on the field input refs, >> if >> >> we always keep the alias, there are many cases that can not be >> promoted. I >> >> collected some cases that already tracked by the JIRA issue: >> >> >> >> [1] https://issues.apache.org/jira/browse/CALCITE-4037 >> >> [2] https://issues.apache.org/jira/browse/CALCITE-3662 >> >> [3] https://issues.apache.org/jira/browse/CALCITE-1584 >> >> >> >> Best, >> >> Danny Chan >> >> 在 2020年10月21日 +0800 PM2:49，JiaTao Tao <[email protected]>，写道： >> >>> Hi fellows >> >>> I found in some place, we just call `project(Iterable<? extends >> RexNode> >> >>> nodes) `, but this will lose alias, why don't we try to call >> >>> `project(Iterable<? >> >>> extends RexNode> nodes, Iterable<String> fieldNames) ` to keep alias? >> >>> >> >>> Regards! >> >>> >> >>> Aron Tao >> >> >> >
