Which two statements are true about Oracle Managed Files (OMF)?
A.
OMF cannot be used in a database that already has data files created with user-specified
directions.
B.
The file system directions that are specified by OMF parameters are created automatically.
C.
OMF can be used with ASM disk groups, as well as with raw devices, for better file
management.
D.
OMF automatically creates unique file names for table spaces and control files.
E.
OMF may affect the location of the redo log files and archived log files.
Explanation:
B: Through initialization parameters, you specify the file system directory to be used
for a particular type of file. The database then ensures that a unique file, an Oracle-managed file,
is created and deleted when no longer needed.
D: The database internally uses standard file system interfaces to create and delete files as
needed for the following database structures:
Tablespaces
Redo log files
Control files
Archived logs
Block change tracking files
Flashback logs
RMAN backups
Note:
* Using Oracle-managed files simplifies the administration of an Oracle Database. Oraclemanaged files eliminate the need for you, the DBA, to directly manage the operating system files
that make up an Oracle Database. With Oracle-managed files, you specify file system directories
in which the database automatically creates, names, and manages files at the database object
level. For example, you need only specify that you want to create a tablespace; you do not need to
specify the name and path of the tablespace’s datafile with the DATAFILE clause.
Reference: What Are Oracle-Managed Files?
Not A. New files can be created as managed files while old ones are administered in the old way. Thus, a database can have a mixture of Oracle-managed and unmanaged files.
Not B. The file system directory specified by either of these parameters must already exist: the database does not create it. The directory must also have permissions to allow the database to create the files in it.
Not C. The Oracle-managed files feature is not intended to ease administration of systems that use raw disks.
So DE
DE
DE not B because db_create_file_dest must exists to be specified as parameter value
D & E,
B is wrong as OMF will not create directory structure. It must be present.
DE