DBMS_FILE_TRANSFER Package in Oracle Database 10g
Oracle 10g has introduced the
DBMS_FILE_TRANSFER package which provides an API for copying binary files between database servers.
Common Usage Notes
All of the the currently supported procedures have some common usage notes listed below:
- The user must have read privilege on the source directory object and write privilege on the destination directory object.
- The procedure converts directory object names to uppercase unless they are surrounded by double quotes.
- Files to be copied must be multiples of 512 bytes in size.
- Files to be copied must be equal to or less than 2 terabytes in size.
- File transfers are not transactional.
- Files are copied as binary, so no character conversions are performed.
- File copies can be monitored using the V$SESSION_LONGOPS view.
COPY_FILE
The
COPY_FILE procedure allows you to copy binary files from one location to another on the same server.
-- Create the source and destination directory objects.
CREATE OR REPLACE DIRECTORY db_files_dir1 AS '/u01/oradata/DB10G/';
CREATE OR REPLACE DIRECTORY db_files_dir2 AS '/u02/oradata/DB10G/';
-- Switch a tablespace into read only mode so we can
-- use it for a test file transfer.
ALTER TABLESPACE users READ ONLY;
-- Copy the file.
BEGIN
DBMS_FILE_TRANSFER.COPY_FILE(
source_directory_object => 'DB_FILES_DIR1',
source_file_name => 'USERS01.DBF',
destination_directory_object => 'DB_FILES_DIR2',
destination_file_name => 'USERS01.DBF');
END;
/
-- Switch the tablespace back to read write mode.
ALTER TABLESPACE users READ WRITE;
Checking the destination directory will reveal that the file has been copied successfully.
GET_FILE
The
GET_FILE procedure allows you to copy binary files from a remote server to the local server.
-- Login to the remote server.
CONN system/password@remote
-- Create the source directory object and switch mode of a tablespace.
CREATE OR REPLACE DIRECTORY db_files_dir1 AS '/u01/oradata/DB10G/';
ALTER TABLESPACE users READ ONLY;
-- Login to the local server.
CONN system/password@local
-- Create the destination directory object and a database link.
CREATE OR REPLACE DIRECTORY db_files_dir2 AS '/u02/oradata/DB10G/';
CREATE DATABASE LINK remote CONNECT TO system IDENTIFIED BY password USING 'REMOTE';
-- Get the file.
BEGIN
DBMS_FILE_TRANSFER.GET_FILE(
source_directory_object => 'DB_FILES_DIR1',
source_file_name => 'USERS01.DBF',
source_database => 'REMOTE',
destination_directory_object => 'DB_FILES_DIR2',
destination_file_name => 'USERS01.DBF');
END;
/
-- Login to the remote server.
CONN system/password@remote
-- Switch the tablespace back to read write mode.
ALTER TABLESPACE users READ WRITE;
Checking the destination directory on the local server will reveal that the file has been copied successfully.
PUT_FILE
The
PUT_FILE procedure allows you to copy binary files from the local server to a remote server.
-- Login to the remote server.
CONN system/password@remote
-- Create the destination directory object.
CREATE OR REPLACE DIRECTORY db_files_dir2 AS '/u02/oradata/DB10G/';
-- Login to the local server.
CONN system/password@local
-- Create the source directory object, database link and switch mode of a tablespace.
CREATE OR REPLACE DIRECTORY db_files_dir1 AS '/u01/oradata/DB10G/';
CREATE DATABASE LINK remote CONNECT TO system IDENTIFIED BY password USING 'REMOTE';
ALTER TABLESPACE users READ ONLY;
-- Put the file.
BEGIN
DBMS_FILE_TRANSFER.PUT_FILE(
source_directory_object => 'DB_FILES_DIR1',
source_file_name => 'USERS01.DBF',
destination_directory_object => 'DB_FILES_DIR2',
destination_file_name => 'USERS01.DBF',
destination_database => 'REMOTE');
END;
/
-- Switch the tablespace back to read write mode.
ALTER TABLESPACE users READ WRITE;