online and offline backup
Posted:
can anyone say the difference between online and offline backup?
Logs do require for any activity((Like Insert, Delete, Update etc.,)) on database
Online backup - Logs will be retained
Offline backup - Logs will be reused
Offline backup --
When you take a offline backup, you will have to force all the users who are connect to the database. this is called as Offline... This mean no activity on the database end execpt backup engine
using offline backup you can only restore the DB till the last full offline backup
Offline backup are also called full backup.
Online Backup --
Users are connect to database and doin DB activties(Insert, update, delete etc.,). At this situtaion if you want to take a backup without distrubing their activity on the database is called online.
You will be able to take Incremental/Delta backups only when your DB marked for online backups
Online backups are used for point in time recovery (With the retained logs)
To take online backups on any database, you will have to mark your database to allow online backups. To make database online there are different procedures for dirrent RDBMS(MS-SQL, ORACLE, DB2 etc.,) . Based on the RDBMS you will have to consult your DBA to setup online backups for your environment.
Usually online backups will be taken for production environments.
Hope this helps, if you need more let me know ...