RE: Please a parameter to disable undo, like _disable

From: Juan Carlos Reyes Pacheco <jreyes_at_dazasoftware.com>
Date: Wed, 6 Oct 2004 10:13:28 -0400
Message-Id: <4163FD88.000001.01620@DAZA-MGEJCA5J7T>

HI Lex,
Some time ago, I was testing discrete transaction, and I didn't saw difference, I asked tom and I remember he toldme it was obsolete.

"
Tom,
What is discrete transaction. This is the first time I hear about something like
this

Followup:
it is obsoleted -- you need not learn about it. it was a way to perform a transaction in very very very very special cases that
did not generate undo. not used, not useful, not talked about.

But Tom didn't says it don't works
In your experience Lex, it works?
I'm going to test it

Juan Carlos Reyes Pacheco
OCP
-------Original Message-------

From: Lex de Haan
Date: 10/06/04 03:30:41
To: Mark.Bobak_at_il.proquest.com; jreyes_at_dazasoftware.com; oracle-l_at_freelists org
Subject: RE: Please a parameter to disable undo, like _disable_logging

Hi Mark,

about the discrete transactions: try this one...

SQL> describe dbms_transaction

PROCEDURE ADVISE_COMMIT
PROCEDURE ADVISE_NOTHING
PROCEDURE ADVISE_ROLLBACK

PROCEDURE BEGIN_DISCRETE_TRANSACTION <<< PROCEDURE COMMIT
PROCEDURE COMMIT_COMMENT
...

SQL> Kind regards,
Lex.

visit http://www.naturaljoin.nl

skype me <callto://lexdehaan>

-----Original Message-----

From: oracle-l-bounce_at_freelists.org
[mailto:oracle-l-bounce_at_freelists.org]On Behalf Of Bobak, Mark Sent: Wednesday, October 06, 2004 00:29
To: jreyes_at_dazasoftware.com; oracle-l_at_freelists.org Subject: RE: Please a parameter to disable undo, like _disable_logging

In general, the answer is that it's not possible. UNDO is integral to Oracle's recovery processes.

Consider what would happen without undo if the instance crashed unexpectedly....what happens to
partially complete transactions? W/ undo, instance recovery will read undo and roll back any
incomplete transactions. Without undo, there would be no recourse. That's just one simple
example, I'm sure there are many more.

The only time undo can be "disabled" is in the case of direct load inserts. This only
works because brand new blocks are being formatted and added to the database. There is
no "before image" required in this case.

Direct load inserts are well-covered in the docs, so I won't go into further detail.

Hope that helps,

-Mark

PS There used to be things called discrete transactions, but they were deprecated before
I really learned what they were or how they worked. I'm pretty sure they don't even exist
in 9i....maybe not even in 8i, I'm not sure, never really used them.

Mark J. Bobak
Oracle DBA
ProQuest Company
Ann Arbor, MI

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http://www.freelists.org/webpage/oracle-l Received on Wed Oct 06 2004 - 09:09:11 CDT