Using DBMS_FILE_TRANSFER or RMAN to move datafiles from one Disk Group to another

To move datafile from one disk group to another you need to follow these steps:

1-Identify datafiles that will be moved:
SQL>select
file_name
from
dba_data_files;

2-Identify the disk group destination
--Connect to ASM instance
SQL> select
name
from
v$asm_diskgroup;

3-Take the datafile OFFLINE
SQL>alter database datafile 'file_name' offline;

4-Copy the file using either dbms_file_transfer or RMAN:
--DBMS_FILE_TRANSFER