[Oracle DataBase Server 12.1 installation on Windows 2008 Server]: Change default datafile location
sqlplus / as sysdba
To create folders for files:
SQL> HOST md E:\app\oracle\oradata\ora121\data
SQL> HOST md E:\app\oracle\oradata\ora121\indexes
SQL> HOST md E:\app\oracle\oradata\ora121\undo
SQL> HOST md E:\app\oracle\oradata\ora121\temp
SQL> select name from v$datafile;
SQL> shutdown immediate;
SQL> startup mount;
SQL> HOST MOVE E:\app\oracle\oradata\ora121\SYSTEM01.DBF E:\app\oracle\oradata\ora121\data\SYSTEM01.DBF
SQL> HOST MOVE E:\app\oracle\oradata\ora121\SYSAUX01.DBF E:\app\oracle\oradata\ora121\data\SYSAUX01.DBF
SQL> HOST MOVE E:\app\oracle\oradata\ora121\USERS01.DBF E:\app\oracle\oradata\ora121\data\USERS01.DBF
SQL> HOST MOVE E:\app\oracle\oradata\ora121\UNDOTBS01.DBF E:\app\oracle\oradata\ora121\undo\UNDOTBS01.DBF
SQL> HOST MOVE E:\app\oracle\oradata\ora121\TEMP01.DBF E:\app\oracle\oradata\ora121\temp\TEMP01.DBF
SQL> ALTER DATABASE RENAME FILE 'E:\app\oracle\oradata\ora121\SYSTEM01.DBF' TO 'E:\app\oracle\oradata\ora121\data\SYSTEM01.DBF';
SQL> ALTER DATABASE RENAME FILE 'E:\app\oracle\oradata\ora121\SYSAUX01.DBF' TO 'E:\app\oracle\oradata\ora121\data\SYSAUX01.DBF';
SQL> ALTER DATABASE RENAME FILE 'E:\app\oracle\oradata\ora121\USERS01.DBF' TO 'E:\app\oracle\oradata\ora121\data\USERS01.DBF';
SQL> ALTER DATABASE RENAME FILE 'E:\app\oracle\oradata\ora121\UNDOTBS01.DBF' TO 'E:\app\oracle\oradata\ora121\undo\UNDOTBS01.DBF';
SQL> ALTER DATABASE RENAME FILE 'E:\app\oracle\oradata\ora121\TEMP01.DBF' TO 'E:\app\oracle\oradata\ora121\temp\TEMP01.DBF';
SQL> alter database open;
SQL> quit