Oracle introduced Oracle Managed Files (OMF) concept in Oracle 9i. OMFs simplify the administration task of an Oracle Database. Oracle manages these files for the administrators.
Prior to Oracle9i, when you dropped a tablespace you would also have to manually remove the physical datafile associated with that tablespace from the operating system.
If a wrong datafile is removed manually from the Operating System, then the option remaining was to do the recovery of the file from the recent backup, which means either a bigger downtime or the tablespace containing the removed datafile was unavailable for the users.
This manual task of removing the datafile is taken over by Oracle. Hence, with Oracle-Managed Datafiles physical file management is left to the database itself.
Oracle-Managed Datafiles (OMFs) give Oracle the ability to manage database files for you.The database internally uses standard file system interfaces to create and delete files as needed.
OMFs can be used when creating database datafiles, tempfiles, online redo logfiles, and database control files.
Before using OMFs, the database must be configured for OMF use. After the database is configured
If the database creates an Oracle Managed Control File, and the database uses SPFILE, then the control_file parameter is automatically added to the SPFILE with the location of the control file.
If PFILE is used instead of SPFILE, then the control_file parameter needs to be added manually else the instance startup will fail.
Prior to Oracle9i, when you dropped a tablespace you would also have to manually remove the physical datafile associated with that tablespace from the operating system.
If a wrong datafile is removed manually from the Operating System, then the option remaining was to do the recovery of the file from the recent backup, which means either a bigger downtime or the tablespace containing the removed datafile was unavailable for the users.
This manual task of removing the datafile is taken over by Oracle. Hence, with Oracle-Managed Datafiles physical file management is left to the database itself.
Oracle-Managed Datafiles (OMFs) give Oracle the ability to manage database files for you.The database internally uses standard file system interfaces to create and delete files as needed.
OMFs can be used when creating database datafiles, tempfiles, online redo logfiles, and database control files.
Before using OMFs, the database must be configured for OMF use. After the database is configured
If the database creates an Oracle Managed Control File, and the database uses SPFILE, then the control_file parameter is automatically added to the SPFILE with the location of the control file.
If PFILE is used instead of SPFILE, then the control_file parameter needs to be added manually else the instance startup will fail.
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