Hot Backups, Redo, and Fractured Blocks

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Hot Backups, Redo, and Fractured Blocks

Postby shrinika » Wed Jan 02, 2013 3:38 am

Tim, I read the below link and have question.

Code: Select all
http://www.oraclealchemist.com/oracle/hot-backups-redo-and-fractured-blocks/


When the tablespace is begin backup mode, oracle does not update the scn on data file header. Instead, it update the SCN
on the redo block. However, it continue writing in the data file. but the data file header is frozen. When we bring the data file
to end backup mode, it will repair the data file and reconcile the data file with redo block.

My question is, when log switch happens, the redo log file will be archived to archived redo logs. when we bring the data file
to end backup mode, the info in redo log file will be disappeared and how does oracle reconcile the block when info is lost in
redo log file?

Please help me to understand.
shrinika
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Re: Hot Backups, Redo, and Fractured Blocks

Postby Tim... » Wed Jan 02, 2013 8:47 am

Hi.

It only needs to know the latest SCN, so that will always be in an online redo log.

Cheers

Tim...
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Re: Hot Backups, Redo, and Fractured Blocks

Postby shrinika » Thu Jan 03, 2013 3:51 am

Thanks Tim!
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Re: Hot Backups, Redo, and Fractured Blocks

Postby Tim... » Thu Jan 03, 2013 8:22 am

:)
Tim...
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Oracle ACE of the Year 2006 - Oracle Magazine Editors Choice Awards
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OCP DBA 7.3, 8, 8i, 9i, 10g, 11g
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