How to recover accidentally deleted data in oracle database
Steps to recover accidentally deleted data: Check whether there is accidentally deleted data in the recycle bin. Use flashback queries to recover accidentally deleted data (for example, if the timestamp is shortly after the accidental deletion). Restore data from backup (if Recycle Bin and Flashback queries cannot be restored).
Oracle database accidentally deleted data recovery
Steps to recover accidentally deleted data
After accidentally deleting data in the Oracle database, the recovery steps generally include the following aspects:
- Check the Recycle Bin
- Use Flashback Query
- Restore from backup
1. Check the Recycle Bin
Oracle database provides a recycle bin function that can store accidentally deleted data. After accidentally deleting, first check whether there is data to be recovered in the Recycle Bin. If the data is still in the Recycle Bin, you can restore it.
2. Using Flashback Query
Flashback query is a function that allows querying the database status at a certain point in time in the past. If the accidentally deleted data occurs within a short period of time, you can use flashback query to recover the data.
3. Restore from backup
If neither Recycle Bin nor flashback query can restore the data, you need to restore from backup. Oracle Database provides various backup options such as RMAN backup, export/import, and database snapshots. Depending on the backup type, choose the appropriate recovery method.
Detailed steps for recovery
Check the Recycle Bin
- Connect to the database and run the following query:
<code>SELECT * FROM recyclebin;</code>
- Determine whether the data to be recovered is included.
Using Flashback Query
- Connect to the database and run the following query:
<code>SELECT * FROM tablename AS OF TIMESTAMP</code>
- where
tablename
is the name of the table where the data was accidentally deleted,TIMESTAMP
is the specific timestamp of the data to be restored.
Restore from backup
- Use the corresponding restore command based on the backup type. For example, for RMAN backup:
<code>rman target / restore database; recover database;</code>
Recovery Notes
- It is very important to detect and recover accidentally deleted data in time.
- Regularly backing up the database is a best practice for data protection.
- Before performing the recovery operation, be sure to make a backup or dump just in case.
- If the data cannot be recovered through the above methods, please contact Oracle technical support.
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