How to recover deleted data in oracle

Deleted data in Oracle can be recovered from the recycle bin: 1. Confirm that the data is still in the recycle bin; 2. Use the FLASHBACK TABLE statement to restore the data; 3. Submit the changes to make the recovery permanent. Note: Only data deleted within a transaction can be restored, and the restore operation may result in the loss of other user data.

How to recover deleted data in Oracle

In Oracle database, deleted data can be recovered from Site recovery. The recycle bin is a special table space used to store deleted data.

Steps to recover deleted data:

1. Confirm that the data is still in the recycle bin

Check using the following query Is the data still in the Recycle Bin:

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

2. Recover data

To recover data, use the following syntax:

<code>FLASHBACK TABLE table_name TO BEFORE DROP;</code>

where table_name is the name of the table to be restored.

3. Submit changes

After restoring the data, you must submit the changes to make the restoration permanent:

<code>COMMIT;</code>

Notes:

• Only deleted data in transactions that have rollback segments enabled can be recovered.
• If the data has been overwritten or vacuumed, it cannot be recovered.
• Restore operations may result in data loss for other users, so caution should be used before restoring.

Advanced recovery options:

• Flashback Query: Allows queries to restore previous data versions without restoring the entire table .
• Flashback Drop: Recover a deleted table or object, including its data and definitions.
• Time Travel Query: Allows querying data at a specific point in time, even if the data has been modified or deleted.

Recommendation:

• Back up the database regularly to prevent data loss.
• Clear the Recycle Bin regularly to free up space and improve performance.
• Before recovering your data, carefully consider the potential consequences.

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