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

-----Original Message-----
From: oracle-l-bounce_at_freelists.org
[mailto:oracle-l-bounce_at_freelists.org] On Behalf Of Juan Carlos Reyes Pacheco
Sent: Tuesday, October 05, 2004 7:18 PM
To: oracle-l_at_freelists.org
Subject: Please a parameter to disable undo, like _disable_logging=20

Hi, I searched but I didn't find it, please do you know some parameter like
_disable_logging (disables logging),=20
to disable undo.

SELECT KSPPINM, KSPPSTVL=20
FROM X$KSPPI A, X$KSPPSV B
WHERE A.INDX=3DB.INDX AND SUBSTR(KSPPINM,1,1) =3D '_' and upper(KSPPINM) like '%UNDO%' ;
=20

This is only to speed my test database, thanks.
=20

Juan Carlos Reyes Pacheco
OCP

--
http://www.freelists.org/webpage/oracle-l
--
http://www.freelists.org/webpage/oracle-l