Oracle - What
are the Predefined Tablespaces in a database? - April 10, 2009
at 11:00 AM
What are the Predefined Tablespaces in a
When you create a new database, Oracle server will create 4
required tablespaces for the new database:
- Every Oracle database contains a tablespace named SYSTEM
- Created automatically during the database creation
- It is always online when the database is open
- Gets installed as an auxiliary tablespace to the SYSTEM
tablespace during the database creation
- Database components that otherwise create and use separate
tablespaces then occupy this tablespace.
- UNDO tablespaces are used for the storage of undo information.
- No other segment types can be created in undo tablespaces.
- Each database contains zero or more undo tablespaces.
- Only a single undo tablespace is assigned to an Oracle
instance in automatic undo management mode.
- At least one default temporary tablespace needs to be defined
when creating a database when the SYSTEM tablespace is locally
- A locally managed SYSTEM tablespace cannot be used for default
A table space can be considered as a storage location where the
database objects are kept...........
Tablespaces is a logical storage unit. It is used to group
related logical structures together........
SYSTEM Tablespace, SYSAUX Tablespace, UNDO Tablespace, TEMP
Tablespace fragmentation can be prevented by using PCTINCREASE
command. PCTINCREASE is the percentage a new subsequent extent will