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high water mark (merged) [message #382719]

Fri, 23 January 2009 14:38

varunvir
Messages: 389
Registered: November 2007

Senior Member

Hi Experts,
To bring th high water mark down which is better option if table does not have any index:-
1,Truncate the table and get the data back
2,Dropping the table and then using expdp/impdp.
3,alter table tablename enable row movement.
alter table tablename shrink space.
Regards,
Varun Punj

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Re: high water mark [message #382722 is a reply to message #382719]

Fri, 23 January 2009 14:47

BlackSwan
Messages: 26766
Registered: January 2009
Location: SoCal

Senior Member

Better?
Better based upon which metric; elapsed time, CPU cycles consumed, # Input/output operations, etc?

You can have it good, fast, or cheap; pick any two.

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Re: high water mark [message #382725 is a reply to message #382722]

Fri, 23 January 2009 14:59

varunvir
Messages: 389
Registered: November 2007

Senior Member

Thanks for the reply BlackSwan.
I have one doubt if impdp/expdp really brings the high water mark down.It will be fast if I use expdp/impdp but I am not
sure if it will be good too.
Regards,
Varun Punj,

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Re: high water mark [message #382734 is a reply to message #382719]

Fri, 23 January 2009 15:47

Mahesh Rajendran
Messages: 10707
Registered: March 2002
Location: oracleDocoVille

Senior Member
Account Moderator

It is hard to generalize.
First two requires downtime to the application.
The last does not.
If your application would somehow use ROWIDs, then you might be in trouble if you do not use the precautions and you must be using ASSM.
The doc has a pretty clear writeup on this.
http://download.oracle.com/docs/cd/B19306_01/server.102/b14231/schema.htm#ADMIN10161

[Updated on: Fri, 23 January 2009 15:54]

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Re: high water mark [message #382739 is a reply to message #382734]

Fri, 23 January 2009 19:58

varunvir
Messages: 389
Registered: November 2007

Senior Member

Thanks Mahesh,
I will go with the impdp/expdp option during off peak hours.
Regards,
Varun Punj

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