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From Atri Sharma <atri.j...@gmail.com>
Subject Re: Optimization around Multiple ORs and constants
Date Thu, 16 Jul 2015 10:36:53 GMT
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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