RE: Defrag/Reorg Tool

From: Bobak, Mark <>
Date: Thu, 12 Feb 2009 18:32:31 -0500
Message-ID: <>

Good point, David. I forgot to mention shrink space....


Mark J. Bobak
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ProQuest...Start here.

From: [] On Behalf Of David Barbour Sent: Thursday, February 12, 2009 6:08 PM To:
Cc:; Oracle L Subject: Re: Defrag/Reorg Tool

Okay. What version of Oracle are you on? Are you using locally managed tablespaces and ASSM? Check out the command 'alter table shrink space' (in conjunction with alter table enable row movement ). You need to identify which tables are using those blocks, shrink them, then resize the datafiles. Please nbe careful and understand what might happen if in fact you need to invoke row movement. If you've got long raw data, you'll probably have to use exp/imp to reorg the tables. On Thu, Feb 12, 2009 at 5:29 PM, Deepak Sharma <<>> wrote: I should clarify the need for this tool.

At some point we over-allocated the tablespaces. So, we have large datafiles, but with lot of space not being used (holes) currently. We want to reclaim this space, such as by shrinking (resize) the datafiles. But, since there are one or blocks at the end of the datafile in a lot of cases, the shrink doesn't work very well. If instead there is a tool that can move the blocks that are at the end of the datafile(s) to somewhere in the beginning of the free space, the resize could work.


From: Dan Norris <<>> To: "<>" <<>> Cc: Oracle L <<>> Sent: Thursday, February 12, 2009 4:13:17 PM Subject: Re: Defrag/Reorg Tool

I suggest you review a presentation by Tom Kyte on reorganizing objects that he gave yesterday at RMOUG. I expect it should be on his website somewhere.

Short version: you probably don't need to do anything.


Sent from my iPhone

On Feb 12, 2009, at 3:00 PM, Deepak Sharma <<>> wrote: I wanted to get recommendations on tools for online reorg/defrag of multi-terrabyte Oracle database.

Thanks in advance for your feedback.


-- Received on Thu Feb 12 2009 - 17:32:31 CST

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