Re: changing the isolation level

From: DA Morgan <damorgan_at_psoug.org>
Date: Tue, 16 Jan 2007 15:34:37 -0800
Message-ID: <1168990472.226002@bubbleator.drizzle.com>

Ed Prochak wrote:

>> If I am counting 750K transactions over a five minute period, of what
>> consequence is it if I overcount even a few hundred because of transaction
>> rollback?

>
> so what is you error margin? If you counted only commited transactions,
> you "might" undercount a little, but this is a statistical sample. you
> are looking for a running average. I do not see the justification for
> counting uncommited transactions.

Worse than that counting uncommitted transactions might well provide horribly incorrect information.

What would be, for example, the result of counting during this?

BEGIN

   FOR i IN 1..99999999999999999999 LOOP
     INSERT INTO t VALUES (i);

   END LOOP;
   ROLLBACK;
END;
/

If the OP spent more time studying best practices such as using UNDO rather than rollback, using resumable transactions, etc. the only thing worth watching would be with a system trigger for AFTER SERVERERROR on the database.

-- 
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 Tue Jan 16 2007 - 17:34:37 CST