RE: Does Index get updated ??

From: Cary Millsap <cary.millsap_at_hotsos.com>
Date: Mon, 11 Oct 2004 20:12:02 -0500
Message-ID: <001801c4aff8$7afe8fb0$06000200@CVMLAP02>

You may have to do a 10200 or look at a block dump to figure out whether = a
cached block has been "touched" or not. If the operation doesn't = motivate a
PIO, a buffer busy wait, or the like, then you're not going to see it in = the
10046 data.

Cary Millsap
Hotsos Enterprises, Ltd.
http://www.hotsos.com
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-----Original Message-----
From: oracle-l-bounce_at_freelists.org =
[mailto:oracle-l-bounce_at_freelists.org]
On Behalf Of Bach, Peter
Sent: Monday, October 11, 2004 1:57 PM
To: zhu chao; sat0789_at_fastmail.fm
Cc: oracle-l_at_freelists.org
Subject: RE: Does Index get updated ??

Sorry, didn't clarify previous e-mail in enough details - with sql trace I was referring to event 10046 (extended sql trace).

Regards,
pba

-----Original Message-----
From: zhu chao [mailto:zhuchao_at_gmail.com]=3D20 Sent: Friday, 8 October 2004 5:52 PM
To: Bach, Peter
Cc: sat0789_at_fastmail.fm; oracle-l_at_freelists.org Subject: Re: Does Index get updated ??

no, the index file is not updated when the loan key is the same. you can alter index tablespace read only and verify it. I don't think sql_trace will show you the whether the index is updated or not.

On Sat, 9 Oct 2004 09:27:50 +1000, Bach, Peter <pbach_at_ea.com> wrote:
> Tom Kyte has always advocated not updating or setting a value to the
> same value. So I guess the short answer is yes. But the easiest way
> to find out is to run a sql trace on you below statement and verify
your
> trace file.

>=3D20

> Regards,
> pba=3D3D20

>=3D20
>=3D20

> -----Original Message-----
> From: oracle-l-bounce_at_freelists.org
> [mailto:oracle-l-bounce_at_freelists.org] On Behalf Of
sat0789_at_fastmail.fm
> Sent: Friday, 8 October 2004 3:06 PM
> To: oracle-l_at_freelists.org
> Subject: Does Index get updated ??

>=3D20

> Hello All,
> I have a question on index update..

>=3D20
> There is a table (say A) with 10 columns and a unique index (say
column
> loan_key)
> An informatica job updates this table with a where clause of loan_key.
> The job also updates loan_key column even though the value does not
> change. So at an oracle level i see

>=3D20

> update a=3D3D20
> set loan_key =3D3D3D 123,
> b =3D3D3D bbb
> c =3D3D3D ccc
> where loan_key =3D3D3D 123

>=3D20

> will this update statement also cause the index to be updated even
> though the column value does not change.

>=3D20

> Thank You,

>=3D20

> Sat
> --
> http://www.freelists.org/webpage/oracle-l

>=3D20
>=3D20
>=3D20
>=3D20

> --
> http://www.freelists.org/webpage/oracle-l
>=3D20

--=3D20
Regards
Zhu Chao
www.cnoug.org

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Received on Mon Oct 11 2004 - 20:08:49 CDT