To reference existing ASM files, you need to use a fully qualified ASM filename. Your
development database has a disk group named DG2A, the database name is DEV19, and
the ASM file that you want to reference is a datafile for the USERS02 tablespace.
Which of the following is a valid ASM filename for this ASM file?
A.
dev19/+DG2A/datafile/users02.701.2
B.
+DG2A/dev19/datafile/users02.701.2
C.
+DG2A/dev19/users02/datafile.701.2
D.
+DG2A.701.2
E.
+DG2A/datafile/dev19.users.02.701.2
Explanation:
Fully Qualified File Name Form (link)
A fully qualified file name has the following form:
+diskgroup/dbname/filetype/filetypetag.file.incarnation
Where:
+diskgroup is the disk group name preceded by a plus sign. You can think of the plus sign
(+) as the root directory of the Oracle ASM file system, similar to the slash (/) on UNIX or
Linux computers.dbname is the DB_UNIQUE_NAME of the database to which the file belongs.
filetype is the Oracle file type and can be one of the file types shown in Table 7-3.
filetypetag is type-specific information about the file and can be one of the tags shown in
Table 7-3.
file.incarnation is the file/incarnation pair, used to ensure uniqueness.
For example,
filetype = ‘DATAFILE’, Data files and data file copies
filetypetag = ‘tblspname’, Name of the tablespace into which the file is added
“A” and “D” are correct.
“A” is Fully Qualified ASM Filename and “D” is Numeric ASM Filename
https://docs.oracle.com/cd/B28359_01/server.111/b31107/asmfiles.htm#OSTMG94156
Correcting: the answer correct is “B” and not “A”