Difference of having database in ARCHIVE and NOARCHIVELOG MODE

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ARCHIVELOG and NOARCHIVELOG Mode Comparison -

ARCHIVELOG  MODE:

Advantages:
1.    You can perform hot backups (backups when the database is online).
2.    The archive logs and the last full backup (offline or online) or an older backup can completely recover the database without losing any data because all changes made in the database are stored in the log file.

Disadvantages:
1.    It requires additional disk space to store archived log files. However, the agent offers the option to purge the logs after they have been backed up, giving you the opportunity to free disk space if you need it.

NOARCHIVELOG MODE:

Advantages:
1.    It requires no additional disk space to store archived log files.

Disadvantages:
1.    If you must recover a database, you can only restore the last full offline backup. As a result, any changes made to the database after the last full offline backup are lost.
2.    Database downtime is significant because you cannot back up the database online. This limitation becomes a very serious consideration for large databases.

Important!!!

• NOARCHIVELOG mode does not guarantee Oracle database PITR (Point-in-Time-Recovery) recovery if there is a disaster.
• If the Oracle database is expected to maintain in NOARCHIVELOG mode, then it must backup full Oracle database files while the database is offline and can be restored only till last full offline backup time (All changes after that backup are lost).
• When backups scheduled using RMAN utility, ensure that the database runs in ARCHIVELOG mode.