How to restore oracle delete deletion?

Data deleted using DELETE in Oracle can be recovered from the Recycle Bin. Recovery steps include: 1. Confirm that the data is recoverable; 2. Roll back the transaction; 3. Use flashback query; 4. Use undo table space; 5. Use recovery points. However, you need to pay attention to permissions, overlays, and undo table space restrictions. It is recommended to consult an expert before restoring data.

Oracle DELETE How to recover after deletion?

When you use Oracle's DELETE statement to delete data, the data will not be removed directly, but will be moved to the recycle bin (undo tablespace). Therefore, deleted data can be recovered in some cases.

Steps to recover deleted data:

1. Confirm that the data is recoverable: Check whether there is deleted data in the Recycle Bin. You can view it by querying the v$recyclebin view.
2. Rollback transaction: If the deletion operation is performed in the current transaction, the data can be recovered by rolling back the transaction. Use the ROLLBACK statement to roll back.
3. Using Flashback Query: Flashback query allows access to deleted data even if the transaction has been committed. Use the FLASHBACK QUERY statement to specify a specific point in time at which data is to be recovered.
4. Use undo tablespace: If the data has been cleared from the Recycle Bin, you can still try to use undo tablespace to recover the data. Use the GET_UNDO procedure from the DBMS_FLASHBACK package.
5. Use recovery points: If a recovery point has been set, you can restore the database to that point to recover deleted data. Use the RECOVER DATABASE statement.

Things to note:

• Recovering deleted data may require special permissions.
• Recovering data may overwrite new data that has been inserted after deletion.
• If the undo table space has been overwritten, the data cannot be recovered.
• Recovering data is a complex task of database administration and it is recommended to consult an expert or Oracle documentation before attempting it.

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