Bigfile Tablespaces

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Example: Importing Specific Database Object Types In this example, we create a parameter file that has individual include statements. This export will export all database functions, procedures, and any table that has a name that starts with EMP.

 -- Parameter file INCLUDE=FUNCTION INCLUDE=PROCEDURE INCLUDE=TABLE:''LIKE 'EMP%'" DUMPFILE=pump_dir:mydb_%U_objects.dat NOLOGFILE=Y JOB_NAME=specific_objects FULL=y

Along with the preceding parameter file above, we use the following command line to get just what we asked for:

 C:\Oracle\Oracle Database 10g-beta2\BIN>impdp scott/tiger parfile=c:\oracle\admin\mydb\exp\mypar.fil

Another new feature in Oracle Database 10g are bigfile tablespaces (BFTs). This section begins by describing what BFTs are and what they can be used for. It then looks at BFT management issues, such as how to create BFTs, how to migrate an existing tablespace to a BFT, and the changes to the ROWID format associated with BFTs.

What Are Bigfile Tablespaces?

A BFT contains only one datafile, as opposed to a normal tablespace, which might consist of one or more datafiles. The maximum size of a BFT varies based on the database block size. It can range anywhere from 8 terabytes to 128 terabytes. A BFT is always a locally managed tablespace, an undo tablespace, or a temporary tablespace.

Why Bigfile Tablespaces?

BFTs can simplify the management of your database. With a BFT, you need to manage only one datafile per tablespace, as opposed to multiple datafiles. BFTs are also compatible with OMF datafiles, so there is no need to manage datafiles, or even to be aware of the existence of datafiles.

The biggest benefit of BFTs is that they increase the overall storage capacity of your Oracle database significantly. Oracle Database 10g, with BFTs, can now handle 8 exabytes of storage (dependent on the block size), all with fewer (but