Media Recovery of Transportable Tablespaces: Scenario

The transportable tablespace feature of Oracle allows a user to transport a set of tablespaces from one database to another. Transporting a tablespace into a database is like creating a tablespace with preloaded data. Using this feature is often an advantage because:

• It is faster than using the Export or SQL*Loader utilities because it involves only copying datafiles and integrating metadata

• You can use it to move index data, hence avoiding the necessity of rebuilding indexes

Like normal tablespaces, transportable tablespaces are recoverable. However, while you can recover normal tablespaces without a backup, you must have a version of the transported datafiles in order to recover a transported tablespace.

To recover a transportable tablespace, use the following procedure:

1. If the database is open, then take the transported tablespace offline. For example, if you want to recover the users tablespace, then issue:

   ALTER TABLESPACE users OFFLINE IMMEDIATE;
   
   

2. Restore a backup of the transported datafiles with an operating system utility. The backup can be the initial version of the transported datafiles or any backup taken after the tablespace is transported. For example, enter:

   % cp /backup/users.dbf $ORACLE_HOME/oradata/trgt/users01.dbf
   
   

3. Recover the tablespace as normal. For example, enter:

   RECOVER TABLESPACE users
   
   

You may see the error ORA-01244 when recovering through a transportable tablespace operation just as when recovering through a CREATE TABLESPACE operation. In this case, rename the unnamed files to the correct locations using the procedure in "Recovering Through an Added Datafile with a Backup Control File: Scenario".