How to recover deleted oracle database data

There are four ways to recover deleted data in an Oracle database: 1) Undo the most recent commit or rollback; 2) Restore from backup; 3) Use flashback queries; 4) Use log file analysis. It is recommended to back up the database before restoring data. The specific method depends on the backup strategy and database configuration. Some methods may not be available. If the data has been cleared from all backups and log files, restoring the data may not be successful.

Recovery of deleted data in Oracle database

Question:How to recover Oracle database deleted data?

Answer:

Method 1: Undo the most recent commit or rollback

• If the data was recently deleted , and the transaction has not been committed, you can use theUNDOorROLLBACKstatement to undo the changes.
• UNDOundoes changes for a specific session, whileROLLBACKundoes changes for an entire transaction.

Method 2: Restore from Backup

• If you have backed up the database, you can restore the data from the backup.
• Restore the required data from backup using theRMANorIMPORTcommand.

Method 3: Using Flashback Query

• Flashback Query allows you to query deleted data even if the data has been cleared from the undo segment .
• UseFLASHBACK QUERYsyntax to query historical data.

Method 4: Using Log File Analysis

• Oracle servers maintain log files, which record database activity.
• Log files can be analyzed to find relevant records of deleted data and then restored using theRECOVERstatement.

Important:

• Before attempting to restore data, be sure to back up your database in case of further data loss.
• Depending on the backup strategy and database configuration, some methods may not be available.
• If the data has been purged from all backups and log files, restoring the data may not be successful.

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