HOT and COLD Backups in Oracle

In Oracle, we basically use either Offline or Online backup. Here, although the words are different but the meaning is same our offline backup is called as COLD backup and online backup is known as HOT backup.

In Oracle, we basically use either Offline or Online backup. Here, although the words are different but the meaning is same our offline backup is called as COLD backup and online backup is known as HOT backup.

COLD BACKUP

Cold backup is a physical backup in which all the files of a database are copied without any change means it avoids the risk of copying data and hence the image copy can be easily moved to another system having the same operating system. It is the safest way of backup which takes the backup of ALL data, log, and control files. Cold backups are not useful for large databases.

HOT BACKUP

Hot backup is also a physical backup including the risk of coping data because during the hot backup the database is totally open and available to its users. It is used when a full backup of the database is required. For the hot backup the database must be running in the ARCHIVELOG Mode.

The other major difference between hot and cold backups is that , the database must be informed before a tablespace can be backed up i.e when the backup is starting and when it is going to complete. This is done by using these two commands:
Alter tablespace tablespace_name begin backup;
Perform Operating System Backup of tablespace_name datafiles
Alter tablespace tablespace_name end backup;