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Re: JoinPushThroughJoinRule not applied on plan


Check yours intermediate RelNode plan, which is going to be improved by
this rule. The operands and their ordering are important in matching of the
rules.
https://github.com/apache/calcite/blob/master/core/src/main/java/org/apache/calcite/rel/rules/JoinPushThroughJoinRule.java#L87

>From your case the rule should match. Could you share please the plan?

Kind regards
Vitalii


On Tue, May 8, 2018 at 4:24 PM aishwaryaanns@xxxxxxxxx <
aishwaryaanns@xxxxxxxxx> wrote:

> Okay let me rephrase my question.
>
> I am executing a query having inner and left join. The plan generated by
> calcite for that query is like
>
>            inner
>             /     \
>          left      C
>         /    \
>        A      B
>
> But it would be better if it proceeds inner join first, as the row count
> will be reduced further to proceed left join. So the plan needed is,
>
>             left
>             /     \
>        inner     B
>         /    \
>        A      C
>
> So I read through the documentation and found JoinPushThroughJoinRule will
> do so. So I tried applying them (Till now, I am giving only row count to
> statistics). But no change in the plan.
>
> Then I found onMatch() in JoinPushThroughJoinRule.java has
> not been called at all.
>
> How can this be resolved?
>
>
> On 2018/05/04 14:23:00, Michael Mior <mmior@xxxxxxxxxxxx> wrote:
> > I have no immediate answers, but it would be helpful if you could
> provide a
> > complete working example of code that exhibits the problem.
> >
> > --
> > Michael Mior
> > mmior@xxxxxxxxxxxx
> >
> >
> > Le ven. 4 mai 2018 à 03:58, Valli Annamalai <aishwaryaanns@xxxxxxxxx> a
> > écrit :
> >
> > > I wanted to apply JoinPushThroughJoinRule.LEFT and
> > > JoinPushThroughJoinRule.RIGHT to the plan for optimization. So I added
> > > those 2 rules to Program and ran it as a sequence of programs.
> > >
> > > But I am not getting plan applied with these rules
> > >
> > > I did read [here
> > > <
> > >
> https://issues.apache.org/jira/browse/CALCITE-457?focusedCommentId=14205221&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-14205221
> > > >]
> > > that adding rules does not mean that the plan will be better. So sanity
> > > checks may fail. In my case, during onMatch() checks (in matchRecurse()
> > > from ValcanoRuleCall.java), it fails because of no parents for the
> subsets
> > > (getParentRels() returns empty list) .
> > >
> > > Thus there are no successors and the recursion has not been trigerred.
> So
> > > the rules has not been fired (onMatch() in
> JoinPushThroughJoinRule.java has
> > > not been called at all). What can be done for that?
> > >
> > > Any other flags need to be enabled or rules to be added??
> > >
> > >
> > > Thanks in advance
> > >
> >
>