Re: How to Reduce Index clustering Factor without downtime
Date: Sat, 4 Jun 2016 13:22:49 +0530
Message-ID: <CAFW4NVyz8ZPyXiznchkGtr3agZo0hf=P+GYLY4Lx8dy5BkUi9Q_at_mail.gmail.com>
Hi ,
No performance issue . It was just part of understanding performance tuning method better . I was testing different scenarios on my Dev box .
Thanks you for the suggestion . I will try to reduce CF using dbms redef.
Also what factors shall we consider which sorting data for one particular column as it might cause issue for other indexes . Is there a way we can compare
On Sat, Jun 4, 2016 at 12:59 PM, Dimensional DBA < dimensional.dba_at_comcast.net> wrote:
> What is the performance problem that you are trying to solve that you
> believe reducing clustering factor will help you?
>
>
>
> In generic answer to your question you could use dbms_redefnition to move
> your table to being an IOT that matches the index you wish to mirror or if
> you do not want an IOT then you could just perform dbms_redefinition on a
> frequent enough basis to eliminate the problem you believe you have.
>
>
>
> I would answer the first question and determine if this is really a
> necessity.
>
>
>
> *Matthew Parker*
>
> *Chief Technologist*
>
> *Dimensional DBA*
>
> *425-891-7934 (cell)*
>
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>
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>
> *From:* oracle-l-bounce_at_freelists.org [mailto:
> oracle-l-bounce_at_freelists.org] *On Behalf Of *sumit Tyagi
> *Sent:* Saturday, June 4, 2016 12:02 AM
> *To:* Oracle L
> *Subject:* How to Reduce Index clustering Factor without downtime
>
>
>
>
> Hi Oracle-L team ,
>
>
>
> How can Clustering Factor be Reduced : *My Question is how to reduce CF
> in a production OLTP environment where table data is constantly changing
> and we can't afford a downtime . *
>
>
>
> *Clustering Factor (Doc ID 39836.1)*
>
>
> The only method to affect the clustering factor is to sort and then store
> the rows in the table in the same order as in they appear in the index.
> Exporting rows and putting them back in the same order that they appeared
> originally will have no affect. Remember that ordering the rows to suit one
> index may have detrimental effects on the choice of other indexes.
>
>
>
>
>
>
>
> --
>
>
>
> *--*
>
> *BR*
>
> *Sumit Tyagi*
>
> *+91-7829543355*
>
-- *--* *BR* *Sumit Tyagi* *+91-7829543355* -- http://www.freelists.org/webpage/oracle-lReceived on Sat Jun 04 2016 - 09:52:49 CEST