4464912)
Bigfile Tablespace Initialization Parameter Considerations
Although there are no new initialization parameters specific to bigfile tablespaces, the values of
one initialization parameter and a create database parameter can potentially be reduced because
only one datafile is needed for each bigfile tablespace. The initialization parameter is DB_FILES,
and the create database parameter is MAXDATAFILES.
DB_FILES and Bigfile Tablespaces
As you already know, DB_FILES is the maximum number of datafiles that can be opened for this
database. If you use bigfile tablespaces instead of smallfile tablespaces, the value of this parameter
may be lower; as a result, because there are fewer datafiles to maintain, memory requirements are
lower in the System Global Area (SGA).
552 Oracle Database 11g DBA Handbook
MAXDATAFILES and Bigfile Tablespaces
When creating a new database or a new control file, you can use the MAXDATAFILES parameter
to control the size of the control file section allocated to maintain information about datafiles.
Using bigfile tablespaces, you can make the size of the control file and the space needed in the
SGA for datafile information smaller; more importantly, the same value for MAXDATAFILES using
bigfile tablespaces means that the total database size can be larger.
Bigfile Tablespace Data Dictionary Changes
The changes to data dictionary views due to bigfile tablespaces include a new row in DATABASE_
PROPERTIES and a new column in DBA_TABLESPACES and USER_TABLESPACES.
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