How to recover data deleted by oracle delete
The data deleted by DELETE in Oracle can be recovered through the following methods: Restore from backup: The premise is that there is the latest backup; Use the undo table space: The undo table space has rollback segment retention enabled; Use flashback query: View the data before deletion and export it to a new table; use log mining: parse log files to recover data; use third-party tools: use specialized recovery tools to recover data.
How to recover data deleted by Oracle DELETE
Introduction:
## The #DELETE statement is used in Oracle database to delete rows from a table. However, sometimes users may accidentally execute a DELETE statement, resulting in data loss. This article will introduce how to recover data deleted by DELETE in Oracle.Recovery method:
1. Restore from backup:
If you have performed a backup before deleting the data, you can Restore data by restoring backup. This is the simplest method, but it must have an up-to-date backup.2. Use the undo table space:
Oracle database uses the undo table space to store the data modified during the transaction. The DELETE operation also stores deleted row information in the undo tablespace. If the undo tablespace has rollback segment retention enabled, data deleted by DELETE can be recovered within a period of time.3. Use flashback query:
Oracle Flashback function allows users to query data at a certain point in time in the past. By using Flashback queries, you can see what the data looked like before it was deleted and export it to a new table.4. Use log mining:
Oracle log files contain information about database operations, including DELETE operations. Log files can be parsed and deleted data recovered by using log mining tools.5. Third-party tools:
There are some third-party tools that can be specifically used to recover deleted data in Oracle. These tools typically use log mining or other methods to recover data.Note:
- The possibility of recovering your data decreases over time, especially if other operations or updates have been performed.
- Once data loss is discovered, any further operations on the database should be stopped immediately to avoid overwriting the deleted data.
- It is always recommended to perform regular backups to ensure easy recovery in case of data loss.
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