Re: When should one rebuild an index?
From: Shakespeare <whatsin_at_xs4all.nl>
Date: Wed, 31 Dec 2008 11:22:35 +0100
Message-ID: <495b47ec$0$195$e4fe514c@news.xs4all.nl>
>> 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.
Yes, very clear to everyone, so no need to go on with this discussion......
Date: Wed, 31 Dec 2008 11:22:35 +0100
Message-ID: <495b47ec$0$195$e4fe514c@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......
Shakespeare Received on Wed Dec 31 2008 - 04:22:35 CST