I want to take a backup of my database when it is opened. Can anyone help me pls.
asked
How can a Full Backup be performed when the database is open ?
You want to research a 'hot backup'. As you can imagine, not every database can be shutdown for maint activities, so it's a pretty common requirement to do backups with the database open.
If you are using Hot Backup and a SAN or NAS you may be able to speed up your backup time by using their Snapshot feature. We used to perform hot backups by going into hot backup mode and then copying the datafiles to another device. Very resource intensive. Our NetApp filers allow us to take a 'Snapshot' of files on disk and revert to them at any time so we started using that feature instead of copying files. Our hot backups now take only a few minutes and most of that time is switching in and out of Hot Backup mode within the Oracle database.
Here's Oracle's explanation of what's available to you in 11g:
DB Backup Techniques at Oracle
And you probably want to read up on RMAN, the Recovery Manager, which automates backup and recovery:
If you have an older version, things may be different for you. I don't believe RMAN is new to 11 but I am not sure.
