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Once again back with questions pls help [message #318125] Mon, 05 May 2008 17:03 Go to next message
aatishpatel
Messages: 4
Registered: March 2008
Junior Member
hello oracle gurus please help me out with this querry:-


1) Write a query to find out which file has had the most physical read activity?

2) Write a SQL statement to change the retention time of your undo tablespace to 10 mins.

your help is appreciated
Re: Once again back with questions pls help [message #318126 is a reply to message #318125] Mon, 05 May 2008 17:06 Go to previous messageGo to next message
BlackSwan
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Registered: January 2009
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http://www.orafaq.com/forum/t/88153/0/
Please read & follow Posting Guidelines as stated in URL above.

The complete documentation set can be found at http://tahiti.oracle.com
Re: Once again back with questions pls help [message #318132 is a reply to message #318125] Mon, 05 May 2008 18:20 Go to previous messageGo to next message
rlockard
Messages: 19
Registered: April 2008
Location: Baltimore, MD
Junior Member
aatishpatel wrote on Mon, 05 May 2008 18:03
hello oracle gurus please help me out with this querry:-


1) Write a query to find out which file has had the most physical read activity?

2) Write a SQL statement to change the retention time of your undo tablespace to 10 mins.

your help is appreciated


This is sounding like homework questions. So, I'll point you in the correct direction; however I am not going to answer it for you.

For question #1 look at v$filemetric.
For question #2 I am going to assume you are using Automatic Undo Management. So in the init.ora file you need to set UNDO_MANAGEMENT=AUTO. Now because I believe this is homework, I will leave it up to you to find the second parameter that needs to be set. But because I'm a nice guy, I give you a hint it starts with UNDO.

But there is an issue with this you need to know. If you don't have the space then you will not be able to have your 10 minute retention unless you set the GUARANTEE option and you are using 10g or 11g.

-Rob

-Rob
Re: Once again back with questions pls help [message #318150 is a reply to message #318125] Mon, 05 May 2008 22:53 Go to previous message
Michel Cadot
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Registered: March 2007
Location: Nanterre, France, http://...
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In addition, for 1) there is also v$filestat to get a global view for the instance.

Regards
Michel
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