Re: When should one rebuild an index?
From: Bob Jones <email_at_me.not>
Date: Wed, 31 Dec 2008 17:48:49 -0600
Message-ID: <BxT6l.11867$YU2.4606@nlpi066.nbdc.sbc.com>
>>> Bob Jones wrote:
>>> You may be ... I haven't wavered an angstrom.
>>> Perhaps you should reread this thread from the beginning.
>>> To be honest, and I should be, I intentionally let this thread mislead
>>> the conversation just to see if anyone had actually used ANALYZE INDEX
>>> to make these decisions.
>>> Given that I introduced a flagrant and obvious error the result to that
>>> question is clear.
>>> The functionality that might be used is ANALYZE INDEX <index_name>
>>> COMPUTE STATISTICS. That no one noticed I used VALIDATE STRUCTURE
>>> says what needs to be said.
>>> But, having run a full battery of tests using COMPUTE STATISTICS I will
>>> state, here and for the record, that it too provides a metrics that are
>>> not a reliable source of information as to whether an index would
>>> benefit from a rebuild.
Date: Wed, 31 Dec 2008 17:48:49 -0600
Message-ID: <BxT6l.11867$YU2.4606@nlpi066.nbdc.sbc.com>
"Shakespeare" <whatsin_at_xs4all.nl> wrote in message news:495b47ec$0$195$e4fe514c_at_news.xs4all.nl...
> Bob Jones schreef: >> "DA Morgan" <damorgan_at_psoug.org> wrote in message >> news:1230681064.435435_at_bubbleator.drizzle.com...
>>> Bob Jones wrote:
>>>> "DA Morgan" <damorgan_at_psoug.org> wrote in message >>>> news:1230565383.240290_at_bubbleator.drizzle.com... >>>>> Bob Jones wrote: >>>>> >>>>>> I am not surprised you reached this conclusion based on only the >>>>>> example above. >>>>> Rerun my demo and include any and all columns you wish. Then, using >>>>> those columns and the data they contain, make your case as to how it >>>>> constitutes sufficient information to determine an index should be >>>>> rebuilt. >>>> Sufficient information? Are we changing the topic again?
>>> You may be ... I haven't wavered an angstrom.
>>> >> >> Really? From irrelevance to sufficient information seems to be quite a >> shift to me. >> >>>> What a simplistic approach to tuning. If I can make a conclusion that >>>> INDEX_STATS is useless just base on a Mickey Mouse example without any >>>> other data, life would be easy. Anyone has a crystal ball to lend?
>>> Perhaps you should reread this thread from the beginning.
>>>
>>> To be honest, and I should be, I intentionally let this thread mislead
>>> the conversation just to see if anyone had actually used ANALYZE INDEX
>>> to make these decisions.
>>>
>>> Given that I introduced a flagrant and obvious error the result to that
>>> question is clear.
>>>
>>> The functionality that might be used is ANALYZE INDEX <index_name>
>>> COMPUTE STATISTICS. That no one noticed I used VALIDATE STRUCTURE
>>> says what needs to be said.
>>>
>>> But, having run a full battery of tests using COMPUTE STATISTICS I will
>>> state, here and for the record, that it too provides a metrics that are
>>> not a reliable source of information as to whether an index would
>>> benefit from a rebuild.
>> >> Neither of us need to reread the thread. I think it is very clear to >> everyone now. > Yes, very clear to everyone, so no need to go on with this > discussion...... > >
Yup. Received on Wed Dec 31 2008 - 17:48:49 CST