RE: How to do faster updates

From: Fink, Dan <Dan.Fink_at_mdx.com>
Date: Fri, 13 Sep 2002 12:29:32 -0800
Message-ID: <F001.004CFD4C.20020913122932@fatcity.com>

Oops I almost forgot...with an index, you have additional writes for the index blocks.

-----Original Message-----
From: Fink, Dan
Sent: Friday, September 13, 2002 1:24 PM
To: 'ORACLE-L@fatcity.com'
Subject: RE: How to do faster updates

I love being a contrarian...so here goes...

Are you certain you need an index? The time it will take to read the blocks to create an index (space management and full table scan?), analyze the index for the CBO (necessary?), perform the update, then drop the index. Is this amount of time going to be less than doing an update via a full table scan?

I agree with Jerry's 3rd sentence .. 'Make a copy of the table and see if an index helps or not.' That will prove it. Of course, that also takes time...

-----Original Message-----
From: Whittle Jerome Contr NCI [mailto:Jerome.Whittle@scott.af.mil]
Sent: Friday, September 13, 2002 12:48 PM
To: Multiple recipients of list ORACLE-L
Subject: RE: How to do faster updates

Rajesh,

Build an index. If this is something you will do often; and if that column is a good candidate for an index; and if the index wouldn't slow down inserts and updates too much; consider creating an index. Make a copy of the table and see if an index helps or not. If nothing else you could always create an index; do the updates; and drop the index.

Jerry Whittle
ACIFICS DBA
NCI Information Systems Inc.
jerome.whittle@scott.af.mil
618-622-4145

-----Original Message-----
From: Pillai, Rajesh [SMTP:Rajesh.Pillai@nordstrom.com]

Hi All,
I've a table of 10 M records and I want to update some thousand records based on a column which is not a part of any index. Please suggest the quickest way to do this.

Thanks,
Rajesh

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Author: Fink, Dan
  INET: Dan.Fink_at_mdx.com

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Received on Fri Sep 13 2002 - 15:29:32 CDT