How to recover deleted data in oracle

Steps to recover deleted data in Oracle: Check the Recycle Bin: Check whether the Recycle Bin contains deleted data. Rollback operation: Applicable only to transactional databases, delete operations can be undone. Recovery table area: Used in non-transaction mode or when the recycle bin is not enabled, but only in the case of data corruption or table area damage. Flashback table operation: Create a snapshot of a table at a specific point in time in the past, and retrieve deleted data from the snapshot. Use log file recovery: Use when all else fails and you need to manually record the log file location and identify the transactions to be recovered.

Steps to recover deleted data in Oracle

When data is accidentally deleted in an Oracle database, you can Recover through the following steps:

1. View the Recycle Bin

Oracle provides a feature called "Recycle Bin" that can store deleted data. First check if the Recycle Bin contains the data you want to recover:

• Connect to the database and run the following query: SELECT * FROM RECYCLEBIN;
• Find files containing deleted row of data and note the SCN (System Change Number).

2. Rollback operation (transaction database only)

If the database is running in transaction mode, you can use the rollback operation to undo Delete operation:

• Run the following query: ROLLBACK TO SCN <scn-number>;
• replace <scn-number>Replace with the SCN you noted in step 1.

3. Recovery table area (unavailable)

If the database is running in non-transaction mode, or the recycle bin is not enabled, you can use the recovery table methods to recover deleted data. However, this method is only available in cases of data corruption or table area corruption.

4. Flashback table operation

Oracle provides flashback table operation, which can create a table snapshot at a specific point in time in the past. You can use flashback queries to retrieve deleted data from a snapshot:

• Run the following query: SELECT * FROM <table_name> AS OF TIMESTAMP <timestamp>;
• Replace <table_name> with the table name of the deleted data and <timestamp> with the approximate timestamp when the data was deleted.

5. Use log file recovery

If all other methods fail, log file recovery can be used to recover deleted data. This method requires manual recording of log file locations and the ability to identify the transactions to be recovered.

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