New Cross-Platform Transportable Tablespaces

A transportable tablespace allows you to quickly move a subset of an Oracle database from one Oracle database to another. However, in the previous release of Oracle server, you can only move a tablespace across Oracle databases within the same platform.

Oracle 10g is going one step further by allowing you to move tablespace across different platforms.

Benefits

One of the major benefits for organizations that hosts Oracle databases on different platforms is that data can now be moved between databases quickly, across different platforms. Using the new cross-platform transportable tablespaces method to move data is more efficient than the traditional method of export and import.

Supported Platforms and New Data Dictionary Views

Oracle Database 10g supports nine platforms for transportable tablespace.

A new data dictionary view, v$transportable_platform, lists all nine supported platforms, along with platform ID and endian format.

 

PLATFORM_ID	PLATFORM_NAME	ENDIAN_FORMAT
1	Solaris[tm] OE (32-bit)	Big
2	Solaris[tm] OE (64-bit)	Big
3	HP-UX (64-bit)	Big
4	HP-UX IA (64-bit)	Big
5	HP Tru64 UNIX	Little
6	AIX-Based Systems (64-bit)	Big
7	Microsoft Windows NT	Little
8	Linux IA (32-bit)	Little
9	Linux IA (64-bit)	Little

        Table 3.3: Supported platforms for transportable tablespaces.

The v$database data dictionary view also adds two columns, platform ID and platform name:

SQL> select name, platform_id,platform_name 
   2 from   v$database;

NAME     PLATFORM_ID   PLATFORM_NAME
-------    -----------       -----------------------
GRID                 2       Solaris[tm] OE (64-bit)

To transport a tablespace from one platform to another, datafiles on different platforms must be in the same endian format (byte ordering).

The pattern for byte ordering in native types is called endianness. There are only two main patterns, big endian and little endian. Big endian means the most significant byte comes first, and little endian means the least significant byte comes first. If the source platform and the target platform are of different endianness, then an additional step must be taken on either the source or target platform to convert the tablespace being transported to the target format. If they are of the same endianness, then no conversion is necessary and tablespaces can be transported as if they were on the same platform.

Be aware of the following limitations as you plan for transportable tablespace use:

• The source and target database must use the same character set and national character set.
• You cannot transport a tablespace to a target database in which a tablespace with the same name already exists. However, you can rename either the tablespace to be transported or the destination tablespace before the transport operation.
• The set should be self-containing

Convert Datafiles using RMAN

You do not need to convert the datafile to transport a tablespace from an AIX-based platform to a Sun platform, since both platforms use a big endian.

However, to transport a tablespace from a Sun platform (big endian) to a Linux platform (little endian), you need to use the CONVERT command in the RMAN utility to convert the byte ordering. This can be done on either the source platform or the target platform.

RMAN> CONVERT TABLESPACE ‘USERS’
      TO PLATFORM = ‘Linux IA (32-bit)’
      DB_FILE_NAME_CONVERT = ‘/u02/oradata/grid/users01.dbf’, ‘/dba/recovery_area/transport_linux’