Re: Hot backup

Sameer Utrankar (utrankar_at_nyc.pipeline.com) wrote:
: Usual examples of Hot backup scripts are :
 

: Alter tablespace1 begin backup
: backup tablespace1
: alter tablespace1 end backup
 

: alter tablespace2 begin backup
: .
: and so on ?
 

: It is a lot easier to setup and manage a script which does begin backup
: on all tablespaces, backups all and then does end backup on all of them.
: What is the problem in doing so ? Any downside ?

Remember that when a tablespace is in backup mode, the whole db block is saved into the redo and archive logs if it is modified once during the backup period. So what you are opening yourself up to is the possiblity that your redo and archive log generation is significantly larger, especially if the period during which your tablespaces are in backup mode is significantly long.

I actually do exactly what you are suggesting at a lot of my client sites but with the caveat that the client is willing to backup to an offline o/s mirror. This minimizes the hot backup duration to minutes, thus limiting the risk described above.

Johnny Chan
Independent Oracle Specialist Received on Wed Jan 31 1996 - 00:00:00 CET