How to back up table data in oracle database

In Oracle database, there are three main methods to back up table data: Use the EXPORT command to export table data to a file. Using the RMAN tool, table-level backup, incremental backup, and parallel backup are supported. Use Oracle Data Pump with advanced features such as parallel processing, transport sets, and schema object metadata export.

How to back up table data in Oracle database

Backing up table data is an important task in database management to ensure that the data Secure and prevent data loss. In Oracle database, you can back up table data through the following steps:

1. Export data

Use Oracle's EXPORT command to export table data to a file or tablespace. The syntax of this command is as follows:

<code>EXPORT table_name TO [filename|tablespace_name] [OPTIONS]</code>

For example, the following command exports the data of the employees table to a file named employees.dmp:

<code>EXPORT employees TO employees.dmp</code>

2. Use the RMAN tool

Recovery Manager (RMAN) is a backup and recovery tool provided by Oracle. It provides more powerful backup options than the EXPORT command, including:

• Table-level backup: Back up only the specified table without exporting the entire table space.
• Incremental backup: Only backs up data that has changed since the last backup.
• Parallel backup: Use multiple processes to back up data simultaneously.

To use RMAN to back up table data, please follow these steps:

• Start RMAN: rman target /
• Connect To the database: connect username/password
• Backup table:backup table table_name

3. Use Oracle Data Pump

Oracle Data Pump is a data export and import mechanism introduced in Oracle 10g. It is faster than the EXPORT command and offers more features, including:

• Parallel processing: Use multiple processes to process data simultaneously.
• Transfer Sets: Allows data to be exported to multiple files for easier management and transfer.
• Schema object metadata: Export table structures, indexes, and other schema object metadata.

To use Oracle Data Pump to back up table data, follow these steps:

• Enable Data Pump: Replace datumpump_export and datumpump_import Parameters are set to true.
• Export data: expdp username/password DIRECTORY=directory_name DUMPFILE=dumpfile_name.dmp TABLES=table_name

Note: The above backup method Appropriate permissions (such as EXPORT or SYSDBA) need to be granted to execute.

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