How to recover deleted data in oracle

Recovery methods for deleted data in Oracle include: undoing uncommitted transactions; using the flashback function to roll back the database and flashback tables; restoring from backup, which requires restoring the backup and applying logs; using the RMAN utility to restore the database .

Oracle Data Recovery: How to handle deleted data

Introduction
In In Oracle database management, accidental deletion of data often occurs. This article will explore possible methods to recover deleted data in Oracle.

Recovery Method

1. Using Undo
If the data is deleted without committing the transaction, you can use Undo Command to restore it:

<code>ROLLBACK TO <scn>;</scn></code>

where is the System Change Number (SCN) when the delete operation occurred.

2. Use the flashback function
Oracle provides a flashback function that can restore data at a specific point in time. To use this feature:

• Rollback the database to a point in time before the data was deleted:

  <code>ROLLBACK DATABASE TO <timestamp>;</timestamp></code>

• Flashback table to recover deleted data Data:

  <code>FLASHBACK TABLE <table_name> TO <timestamp>;</timestamp></table_name></code>

3. Restore from backup
If you made a backup before deleting the data, you can restore the data from the backup. This method requires restoring the backup and applying any incremental logs.

4. Using Recovery Flash Area (RMAN)
RMAN is an Oracle utility that can be used to recover databases from corrupted or accidentally deleted data. To use RMAN:

• Connect to the target database:

  <code>rman target /</code>

• Start recovery:

  <code>RESTORE DATABASE;</code>

• Apply recovery log:

  <code>RECOVER DATABASE;</code>

• Check whether the data has been recovered:

  <code>SELECT * FROM <table_name>;</table_name></code>

Notes

• Successful recovery depends on how the data was deleted, the recovery method, and the available backups.
• Before attempting to recover deleted data, it is recommended to consult with your Oracle database administrator or support team.
• It is important to back up your database regularly to ensure that data can be recovered in the event of data loss.

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