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From Atri Sharma <atri.j...@gmail.com>
Subject Re: Optimization around Multiple ORs and constants
Date Thu, 16 Jul 2015 11:48:43 GMT
Thanks.

So what changes do you feel arr needed to implement this please?
On 16 Jul 2015 17:17, "Jihoon Son" <jihoonson@apache.org> wrote:

> Yes you can. Please feel free to create any issues on jira.
>
> To support in subquery, only its logical plan will be changed a little bit.
> You can see the changes at https://github.com/apache/tajo/pull/620,
> especially in InPredicate.java if I remember correctly. I can't check it
> right now, so I'll tell you if I'm wrong.
>
> Jihoon
>
> 2015년 7월 16일 (목) 오후 7:36, Atri Sharma
> atri.jiit@gmail.com>님이 작성:
>
> > So after TAJO 680, the way IN is handled will change?
> >
> > On Thu, Jul 16, 2015 at 6:52 AM, Jihoon Son <jihoonson@apache.org>
> wrote:
> >
> > > Nice idea!
> > > Our evaluation of non-subquery IN predicates employs the hash approach,
> > it
> > > would be much faster.
> > >
> > > To do such work, you may need to create a new logical plan rewriter. We
> > > have a plan rewriting system which consists of LogicalOptimizer,
> > > LogicalPlanRewriteRule, and LogicalPlanRewriteRuleProvider.
> > > LogicalOptimizer optimizes the initial query plan according to the
> > rewrite
> > > rules provided by LogicalPlanRewriteRuleProvider. We currently have
> three
> > > LogicalPlanRewriteRules of FilterPushDownRule, ProjectionPushDownRule,
> > and
> > > PartitionedTableRewriter. After
> > > https://issues.apache.org/jira/browse/TAJO-680, InSubqueryRewriteRule
> > will
> > > be added for in-subquery rewriting. If you want to start this work,
> these
> > > will be good examples.
> > >
> > > As always, please feel free to ask any questions If you have.
> > >
> > > Best regards,
> > > Jihoon
> > >
> > > 2015년 7월 16일 (목) 오전 2:37, Atri Sharma <atri.jiit@gmail.com>님이
작성:
> > >
> > > > Hi,
> > > >
> > > > For cases like WHERE col1=val1 OR col1=val2 OR col1=val3 OR col1=val4
> > OR
> > > > col1=val5 where val1,val2,val3,val4,val5 are constants, do we do any
> > > > optimizations? I can imagine conversion to
> IN(val1,val2,val3,val4,val5)
> > > > which will be more optimized.
> > > >
> > > > --
> > > > Regards,
> > > >
> > > > Atri
> > > > *l'apprenant*
> > > >
> > >
> >
> >
> >
> > --
> > Regards,
> >
> > Atri
> > *l'apprenant*
> >
>

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