How to back up tables in Oracle

Oracle provides multiple methods to back up tables: Export utility: Export the table and its data to a text file for later import and recovery. Import Utility: Import export files into the database, create or replace existing tables. Tablespace Import: Instantly restores the entire tablespace, including tables, indexes, and constraints. RMAN Backup Tables: Use Recovery Manager (RMAN) to back up tables, but it is more complex and time-consuming than other methods.

How to use Oracle to back up tables

Oracle provides a variety of methods to back up tables, including:

Using the Export Utility

The Export Utility allows you to export a table and its data to a text file that can be imported later to restore the table.

Steps:

1. Connect to the database as a user with SYSDBA permissions.
2. Run the following command:

<code>EXPDP DIRECTORY=directory_name DUMPFILE=dump_file_name TABLES=table_name</code>

For example:

<code>EXPDP DIRECTORY=my_dir DUMPFILE=my_table.dmp TABLES=my_table</code>

Use the import utility

Using the import utility, you can import exported files into the database and create or replace existing tables.

Steps:

1. Connect to the database as a user with SYSDBA permissions.
2. Run the following command:

<code>IMPDP DIRECTORY=directory_name DUMPFILE=dump_file_name TABLES=table_name</code>

For example:

<code>IMPDP DIRECTORY=my_dir DUMPFILE=my_table.dmp TABLES=my_table</code>

Use tablespace import

Tablespace import allows you to instantly restore an entire tablespace, including its tables, indexes, and constraints.

Steps:

1. Stop the database.
2. Copy the table space file containing the table space data.
3. Start the database and mount it into the target tablespace.

Backing up tables using RMAN

Recovery Manager (RMAN) is a tool for managing Oracle backup and recovery.

Steps:

1. Connect to the database as a user with SYSBACKUP permissions.
2. Create backup set:

<code>BACKUP TABLESPACE tablespace_name;</code>

For example:

<code>BACKUP TABLESPACE my_tablespace;</code>

3. Restore backup set:

<code>RESTORE TABLESPACE tablespace_name;</code>

Note:

• Using RMAN to back up tables is more complex and time-consuming than other methods.
• Choose the most appropriate backup method based on your specific needs and system configuration.

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