Re: ROLLBACK SEGMENT?

Sorry Jeremiah!

John

kirti.deshpande_at_verizon.com wrote:

>Guys, in the next round, please correct Mr. Wilton's first name to -
>Jeremiah.
>
>Cut & paste is a wonderful thing ;-)
>
>
>- Kirti
>
>
>-----Original Message-----
>Sent: Friday, January 25, 2002 10:35 AM
>To: Multiple recipients of list ORACLE-L
>
>
>
>John,
>
>I DISAGREE. The gymnastics of assigning a large rollback segment to an
>export could avoid the snapshot too old error.
>
>I agree with Jeremy when he says export does not generate rollback. But I
>was trying to impress upon him that still an export could end up with the
>snapshot too old message, particularly if there are plenty of active DML
>transactions happening while the export is in progress, or if the export
>uses the consistent parameter, or the rollback segments are not properly
>sized.
>
>To stress my point further, Note:22836.1 on Metalink. I rest my case ;-)
>
>Raj
>
>orantdba <orantdba_at_netscape.net>@fatcity.com on 01/25/2002 08:20:25 AM
>Please respond to ORACLE-L_at_fatcity.com
>Sent by: root_at_fatcity.com
>To: Multiple recipients of list ORACLE-L <ORACLE-L_at_fatcity.com>
>cc:
>
>
>Hi Raj,
>
>Interesting that you first agree with Jeremy and then argue with him. It
>is precisely because
>export does not generate rollback that the "gymnastics" of taking all of
>the other rbs's offline
>will not help anything. It might make you feel better, however :-).
>
>John
>
>Rajesh.Rao_at_chase.com wrote:
>
>
>
>
>Export doesn't generate any rollback, right, so what is it supposed to
>accomplish by doing this incantation?
>
>
>
>
>
>Sorry to press the point, but could you elaborate on how that "COULD"
>possibly make any difference for 'snapshot too old'?
>
>
>
>For the same reason, any other transaction could end up with a snapshot too
>old error. Export does not generate any rollback, but there could be users
>performing DML operations on the table that is being exported, and the
>export needs to be redirected to read from the rollback segments. The
>likelihood of the error being thrown up especially if one uses the
>consistent parameter could be very high, if you dont have a large enough
>rollback segment without an optimal clause.
>
>Raj
>
>
>Jeremiah Wilton <jwilton_at_speakeasy.net>@fatcity.com on 01/23/2002 11:20:40
>AM
>
>Please respond to ORACLE-L_at_fatcity.com
>Sent by: root_at_fatcity.com
>To: Multiple recipien
>ts of list ORACLE-L <ORACLE-L_at_fatcity.com>
>cc:
>
>On Tue, 22 Jan 2002, Rajesh.Rao_at_chase.com wrote:
>
>Hmmmm ... "COULD" help in avoiding snapshot too old errors.
>
>Sorry to press the point, but could you elaborate on how that "COULD"
>possibly make any difference for 'snapshot too old'?
>
>--
>Jeremiah Wilton
>http://www.speakeasy.net/~jwilton
>
>
>Jeremiah Wilton <jwilton_at_speakeasy.net> wrote:
>
>So what does it accomplish to "assign export [to] a particular
>rollback segment?"
>
>Export doesn't generate any rollback, right, so what is it supposed to
>accomplish by doing this incantation?
>
>On Tue, 22 Jan 2002, Jason Rowski wrote:
>
>... you can use the following trick to assign export a
>particular rollback segment -
>
>1) Create a rollback segment tablespace with one large
>segment and bring it online before export.
>2) Offline all existing rollback segments.
>3) Export the database
>4) Offline the large tablespace created earlier.
>5) Bring back the orginals rollback segments online.
>

-- 
Please see the official ORACLE-L FAQ: http://www.orafaq.com
-- 
Author: orantdba
  INET: orantdba_at_netscape.net

Fat City Network Services    -- (858) 538-5051  FAX: (858) 538-5051
San Diego, California        -- Public Internet access / Mailing Lists
--------------------------------------------------------------------
To REMOVE yourself from this mailing list, send an E-Mail message
to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in
the message BODY, include a line containing: UNSUB ORACLE-L
(or the name of mailing list you want to be removed from).  You may
also send the HELP command for other information (like subscribing).