Re: Shrink Table: IEstimating Rollback Space

From: Hemant K Chitale <>
Date: Fri, 17 Oct 2008 22:47:16 +0800
Message-Id: <>

Undo (and Redo !) will be quite noticeable-- more so as you have indexes on the table.

A SHRINK operates as a DELETE (which will be the very significant portion of Undo) *and* an INSERT.
Both operations also have to update Indexes . The Indexes will not shrink until and unless you do a COALESCE or REBUILD.

See MetaLink Note#577375.1 and Bug# 3888229.

Hemant K Chitale

At 04:52 AM Friday, Ian MacGregor wrote:
>I have a 450 GB table with 150 GB of free space. I'd like to shrink the
>table, but I'm not sure how much rollback will be needed. Is there a
>formula? One that accounts for the indexes as well?
>Ian MacGregor
>SLAC National Accelerator Laboratory

Hemant K Chitale

"A 'No' uttered from the deepest conviction is better than a 'Yes' merely uttered to please, or worse, to avoid trouble." Mohandas Gandhi Quotes

Received on Fri Oct 17 2008 - 09:47:16 CDT

Original text of this message