How to recover deleted data in oracle database

Enable Flashback Query and then use a recovery point objective (RPO) or flashback area query table to recover deleted data: 1. Enable Flashback Query to specify how long the database retains data created when a committed transaction . 2. Use RPO to recover data based on a specific point in time, or use a flashback area query table to query a special table that stores the history of deleted data.

How to recover deleted data in Oracle database

Quick answer:

Recovering deleted data in an Oracle database involves the following steps:

1. Enable Flashback Queries
2. Use a recovery point objective (RPO) or flashback area Query table recovery data

Detailed instructions:

1. Enable flashback query

To recover deleted data For data, Flashback Query must be enabled first. This is accomplished by setting the appropriate retention period in the database. The retention period specifies how long the database retains data created when a transaction is committed.

2. Use RPO or flashback area query table to recover data

After enabling flashback query, you can use recovery point objective (RPO) or flashback area query table (Flashbacks Table Queries) to recover deleted data.

Recovery Point Objective (RPO)

RPO allows you to recover data using a specific point in time. To use RPO, you need to know when the data was deleted.

<code class="sql">SELECT * FROM table_name AS OF TIMESTAMP '2023-01-01 12:00:00'</code>

Flashback area query table

The flashback area query table is a special table in Oracle that stores the history of deleted data. You can query these tables to recover deleted data.

<code class="sql">SELECT * FROM table_name@FLASHBACK_TABLE_NAME</code>

Specific example:

Suppose you have a table named "customers" that contains customer data. The customer record with customer ID 1 is deleted. You can use the following query to restore records:

<code class="sql">SELECT * FROM customers AS OF TIMESTAMP '2023-01-01 12:00:00' WHERE customer_id = 1</code>

Alternatively, you can use the flashback region query table:

<code class="sql">SELECT * FROM customers@FLASHBACK_TABLE_NAME WHERE customer_id = 1</code>

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