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Home -> Community -> Mailing Lists -> Oracle-L -> RE: Index rebuilding
I agree with Dick! Always and never are to be used in
cases like "the sun always rises in the east: or "I've
never enjoyed working with Oracle more than I do now"
:)
Regards!
> Looked at Richard Foote's paper. Don't know about
> that. I did prove to
> OTS several years ago that a block could get "lost"
> in an index due to
> deletion/updates that left it empty. I believe that
> got finally fixed
> in Oracle 8i. I've still seen cases of index's
> becoming unbalanced, I
> know the docs day it's impossible, but it does
> happen without the index
> height increasing. And I still believe that index
> deletes don't get
> flushed so efficiently, as Richard suggests. If
> that was the case then
> I can't explain why an index rebuild can cause an
> index to shrink by 30%
> or more. And recent experience still shows that a
> rebuild can cause
> significant performance improvement. And Oracle has
> provided the
> capability to rebuild indexes which is not trivial.
> Therefore, NEVER
> use the word "never" unless your absolutely certain
> that under all
> circumstances it will be absolutely true. And in
> the current context,
> that is the truth, that is, never can never be an
> absolute.
>
> BTW: Since we've a few "myth busters" in the group.
> I appreciate the
> effort these people put into "myth busting", even if
> they are later
> proven to have erred. At a very minimum they start
> discussion and
> re-examination of commonly held beliefs that can
> have changed or lost
> significance over the years(like it's best to have
> all of a tables data
> in the first extent). Such discussion, although
> sometimes the start of
> "Holy Wars", is healthy (not the Holy War though)
> and a necessary part
> of all of us growing. That being said, let it be
> noted that I agree to
> disagree, in part, with Mr Foote.
>
>
> Dick Goulet
> Senior Oracle DBA
> Oracle Certified 8i DBA
> -----Original Message-----
> From: Jared Still [mailto:jkstill_at_gmail.com]=20
> Sent: Friday, November 12, 2004 12:44 PM
> To: oraclel_at_weikop.com
> Cc: oracle-l_at_freelists.org; steve_at_trolltec.co.uk
> Subject: Re: Index rebuilding
>
> On Fri, 12 Nov 2004 11:49:46 +0100, Karsten Weikop
> <oraclel_at_weikop.com>
> wrote:
> > Please read the execellent paper from Richard
> Foote (which can be
> > downloaded from Miracle's site):
> >
>
http://www.miracleas.dk/images/upload/Docs/Richard%20Foote.pdf
> > Conclusion form this paper: Never Rebuild, but
> find the course to the
> > problem.
>
> Never?
>
> I think you will find that statement as difficult to
> support as
> 'always rebuild'.
>
> --=20
> Jared Still
> Certifiable Oracle DBA and Part Time Perl Evangelist
> --
> http://www.freelists.org/webpage/oracle-l
> --
> http://www.freelists.org/webpage/oracle-l
>
-- http://www.freelists.org/webpage/oracle-lReceived on Fri Nov 12 2004 - 17:40:40 CST
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