Yes, I can.
Here is the link:
https://github.com/apache/calcite/blob/7655bd735f10de5be1eca8bb9af475b3b2ac63b6/core/src/main/java/org/apache/calcite/rel/metadata/JaninoRelMetadataProvider.java#L481
Jacques Nadeau <jacq...@apache.org> 于2022年1月17日周一 03:09写道：
> Can you please provide a url link to the line of code you are referring to
> in github?
>
> On Sat, Jan 15, 2022, 5:52 PM guangyuan wang <wangguangy...@apache.org>
> wrote:
>
> > Thank you very much for your answer.
> > I'm reading source code these days, I'm a little confused about the "
> > JaninoRelMetadataProvider.revise()" method.
> > So I'd like to know the reason why invalidate all of the caches of
> HANDLERS
> > when adding a new RelNode class to ALL_RELS.
> >
> > Jacques Nadeau <jacq...@apache.org> 于2022年1月16日周日 02:04写道：
> >
> > > I should you produce a test case that represents the specific concern
> you
> > > have as opposed to proposing a snippet of code. I'm not sure what you
> > > propose is necessary. I think their is implicit expected logic that a
> > > revise should only influence an exception outcome, not a value outcome.
> > > Only value outcomes are cached so I don't see where there would be a
> > > problem.
> > >
> > > If you're revising value outcomes based on revise call (not just
> > exception
> > > outcomes), I think you're probably breaking the expected contract. (I
> say
> > > think here because I don't think docs make this clear and wasn't the
> > person
> > > that wrote the original code.)
> > >
> > > On Sat, Jan 15, 2022, 3:23 AM guangyuan wang <wangguangy...@apache.org
> >
> > > wrote:
> > >
> > > > Dear community
> > > >
> > > > Why should invalidate all of the caches of HANDLERS when adding a new
> > > > RelNode class in JaninoRelMetadataProvider.revise() method?
> > > >
> > > > The Codes are below:
> > > >
> > > > package org.apache.calcite.rel.metadata
> > > >
> > > > public class JaninoRelMetadataProvider implements
> RelMetadataProvider {
> > > >
> > > > synchronized <M extends Metadata, H extends MetadataHandler<M>> H
> > revise(
> > > >
> > > > Class<? extends RelNode> rClass, MetadataDef<M> def) {
> > > > if (ALL_RELS.add(rClass)) {
> > > > HANDLERS.invalidateAll();
> > > > }
> > > > //noinspection unchecked
> > > > return (H) create(def);
> > > > }
> > > >
> > > > }
> > > >
> > >
> >
>
