Re: v$transaction.cr_gets

From: DA Morgan <damorgan_at_psoug.org>
Date: Thu, 05 Jul 2007 23:28:38 -0700
Message-ID: <1183703317.856433@bubbleator.drizzle.com>

Jonathan Lewis wrote:
> "Chuck" <skilover_nospam_at_bluebottle.com> wrote in message
> news:nRbhi.35$fw2.28_at_trnddc04...

>> What exactly does this column represent? The docs simply say 'Consistent
>> gets'. Is it all consistent gets for the transaction? Or is it just gets
>> that required rolling back a change from the undo segment listed in the
>> xidusn column?

>
>
>
> It is all consistent gets made by the
> session since the transaction started.
>
> Other readers might like to ponder the following
> result from a 10.2.0.3 system:
>
> SQL> select log_io, phy_io, cr_get from v$transaction;
>
> LOG_IO PHY_IO CR_GET
> ---------- ---------- ----------
> 14 17 2185
>
> The description in the manual for "Log_io" is "Logical I/O".
> So is this all the logical I/O, or just the logical I/O needed
> to make the transactional changes or what ? Notice
> that the logical I/O is much smaller than the "consistent gets".
>
> (By the way, that's a rhetorical question intended to
> highlight why it's perfectly reasonable for someone
> to ask something that might appear to be a completely
> stupid question about something that's "in the manual").

You are absolutely correct.

But other than yourself, Tom Kyte, and a handful of others no one will be able to answer the OP's question, or your question above, other than to refer to the docs.

For the most part all we know about such matters is what is written at OTN or in your books. And we all know that none of them are perfect no matter the long hours of testing and editing.

Thakns again.

-- 
Daniel A. Morgan
University of Washington
damorgan_at_x.washington.edu (replace x with u to respond)
Puget Sound Oracle Users Group
www.psoug.org

Received on Fri Jul 06 2007 - 01:28:38 CDT