下面是一个测试过程

1。首先创建裸设备：
root@ultra66 # cd /opt/app/oradata/test            
root@ultra66 # ls
control01.ctl  control03.ctl  redo04.log     system01.dbf   tools01.dbf    users01.dbf
control02.ctl  indx01.dbf     redo05.log     temp01.dbf     undotbs01.dbf
root@ultra66 # ln -s /dev/rdsk/c0t0d0s3 hts.dbf
root@ultra66 # ls -l
total 747634
-rw-r-----   1 oracle   oinstall 1613824 May 26 08:46 control01.ctl
-rw-r-----   1 oracle   oinstall 1613824 May 26 08:46 control02.ctl
-rw-r-----   1 oracle   oinstall 1613824 May 26 08:46 control03.ctl
lrwxrwxrwx   1 root     other         18 May 26 08:46 hts.dbf -> /dev/rdsk/c0t0d0s3
-rw-r-----   1 oracle   oinstall 15736832 May 26 07:05 indx01.dbf
-rw-r-----   1 oracle   oinstall 10486272 May 26 07:05 redo04.log
-rw-r-----   1 oracle   oinstall 10486272 May 26 08:45 redo05.log
-rw-r-----   1 oracle   oinstall 199237632 May 26 08:14 system01.dbf
-rw-r-----   1 oracle   oinstall 10493952 May 26 06:50 temp01.dbf
-rw-r-----   1 oracle   oinstall 10493952 May 26 07:05 tools01.dbf
-rw-r-----   1 oracle   oinstall 104865792 May 26 08:44 undotbs01.dbf
-rw-r-----   1 oracle   oinstall 26222592 May 26 07:05 users01.dbf
2。创建一个表空间作为实验文件
root@ultra66 # su - oracle
Sun Microsystems Inc.   SunOS 5.8       Generic Patch   February 2004
You have new mail.
ultra66% sqlplus /nolog

SQL*Plus: Release 9.2.0.1.0 - Production on 星期四 5月 26 08:47:18 2005

Copyright (c) 1982, 2002, Oracle Corporation.  All rights reserved.

SQL> conn /as sysdba
Connected.

SQL> create tablespace test datafile '/opt/app/oradata/test/ht1.dbf' size 6M;

Tablespace created.

3。使用alter database create datafile ... as ...来迁移，首先要把datafile offline

SQL> alter database create datafile '/opt/app/oradata/test/ht1.dbf' as '/opt/app/oradata/test/hts.dbf';
alter database create datafile '/opt/app/oradata/test/ht1.dbf' as '/opt/app/oradata/test/hts.dbf'
*
ERROR at line 1:
ORA-01182: cannot create database file 6 - file is in use or recovery
ORA-01110: data file 6: '/opt/app/oradata/test/ht1.dbf'

SQL> alter database datafile '/opt/app/oradata/test/ht1.dbf' offline;
alter database datafile '/opt/app/oradata/test/ht1.dbf' offline
*
ERROR at line 1:
ORA-01145: offline immediate disallowed unless media recovery enabled

SQL> alter tablespace test offline;

Tablespace altered.

SQL> alter database create datafile '/opt/app/oradata/test/ht1.dbf' as '/opt/app/oradata/test/hts.dbf';

Database altered.

4。检查一下

SQL> select name from v$datafile;

NAME
--------------------------------------------------------------------------------
/opt/app/oradata/test/system01.dbf
/opt/app/oradata/test/undotbs01.dbf
/opt/app/oradata/test/indx01.dbf
/opt/app/oradata/test/tools01.dbf
/opt/app/oradata/test/users01.dbf
/opt/app/oradata/test/hts.dbf

6 rows selected.

5。把表空间online，需要首先recover

SQL> alter tablespace test online;
alter tablespace test online
*
ERROR at line 1:
ORA-01113: file 6 needs media recovery
ORA-01110: data file 6: '/opt/app/oradata/test/hts.dbf'

SQL> alter database recover datafile 6;

Database altered.

SQL> alter tablespace test online;

Tablespace altered.

SQL>

6。ok，完成