How to add datafile as logic volume (LV) on the tablespace in Linux?

On linux terminal;
chown -R oracle:dba /dev/my_vg_ora/example01
chown -R oracle:dba /dev/mapper/my_vg_ora-example01
chmod 777 /dev/my_vg_ora
chmod 660 /dev/my_vg_ora/*

$ sqlplus
Enter user-name: sys as sysdba
@sys
to add database file please execute under query as system database role

SQL> ALTER TABLESPACE MYTABLESPACE ADD DATAFILE '/dev/my_vg_ora/example01' size 8000m reuse

To execute the command, make sure the instance is open and the tablespace is online and also check database datafiles;

SELECT * FROM dba_data_files;