Printable View
hi folks
what is the advantage of specifying 'alter tablespace begin backup'.
and then taking physical backup
Even if i don't specify this and take a physical backup of the datafile,
i will be able to recover the datafile.
Could anybody guide me the advantages of hot bacup
regards
sonia
http://otn.oracle.com/docs/products/...backup.htm#958Quote:
Originally posted by Sonia
hi folks
what is the advantage of specifying 'alter tablespace begin backup'.
and then taking physical backup
Even if i don't specify this and take a physical backup of the datafile,
i will be able to recover the datafile.
Could anybody guide me the advantages of hot bacup
regards
sonia
Hi,
when you switch a tablespace in HotBackup-Mode Oracle not only writes Block-changes to the log, but even whole modified ORacle-Blocks;
Why?
If your Oracle-block would greater than yours OS-Block it coild be happen that your backup-tool reads for example the half Oracle-block, when it tires to rad the next then it ( the Oracle-block ) could be changed. You have backuped an inconsistent Oracle-Block.
Due to HotBackup-Mode Oracle can complete tht Blocks data totally due to the block-wise logging.
The best Method to backup is with rman :
* No HotBackup-Mode
* Smaller Backup-files
* Blockconsitsency-check while backing up
* incremental Backups
* intelligent support due to repository when you recover the db
Orca
Sonia,
You may also find it helpful to use the I/O rate throttling feature of RMAN. This way you can limit the I/O rate in case you have to due a backup during times when the server is in use by many users. I use this technique in scripts which backup archivelog files separately from full database backups because this might have to occur during the daytime. Here is a link to an example script:
http://www.dotcomsolutionsinc.net/pr...ol901_85_.html
David Simpson
http://www.dotcomsolutionsinc.net