1.alter database方法
该方法，可以移动任何表空间的数据文件。
***关闭数据库***
SQL> shutdown immediate
Database closed.
Database dismounted.
ORACLE instance shut down.
***移动数据文件，用oracle用户操作***
[oracle@test ~]$ mv /u01/app/oracle/oradata/test/system01.dbf /oracledb/test/system01.dbf
[oracle@test ~]$ mv /u01/app/oracle/oradata/test/sysaux01.dbf /oracledb/test/sysaux01.dbf
[oracle@test ~]$ mv /u01/app/oracle/oradata/test/undotbs01.dbf /oracledb/test/undotbs01.dbf
[oracle@test ~]$ mv /u01/app/oracle/oradata/test/users01.dbf /oracledb/test/users01.dbf
[oracle@test ~]$ mv /u01/app/oracle/oradata/test/temp01.dbf /oracledb/test/temp01.dbf
[oracle@test ~]$ mv /u01/app/oracle/oradata/test/redo03.log /oracledb/test/redo03.log
[oracle@test ~]$ mv /u01/app/oracle/oradata/test/redo02.log /oracledb/test/redo02.log
[oracle@test ~]$ mv /u01/app/oracle/oradata/test/redo01.log /oracledb/test/redo01.log
***启动到mount状态***
SQL> startup mount
ORACLE instance started.
Total System Global Area 1.0122E+10 bytes
Fixed Size 2237088 bytes
Variable Size 1610616160 bytes
Database Buffers 8489271296 bytes
Redo Buffers 19468288 bytes
Database mounted.
SQL> alter database rename file '/u01/app/oracle/oradata/test/system01.dbf' to '/oracledb/test/system01.dbf';
Database altered.
SQL> alter database rename file '/u01/app/oracle/oradata/test/sysaux01.dbf' to '/oracledb/test/sysaux01.dbf';
Database altered.
SQL> alter database rename file '/u01/app/oracle/oradata/test/undotbs01.dbf' to '/oracledb/test/undotbs01.dbf';
Database altered.
SQL> alter database rename file '/u01/app/oracle/oradata/test/users01.dbf' to '/oracledb/test/users01.dbf';
Database altered.
SQL> alter database rename file '/u01/app/oracle/oradata/test/temp01.dbf' to '/oracledb/test/temp01.dbf';
Database altered.
SQL> alter database rename file '/u01/app/oracle/oradata/test/redo01.log' to '/oracledb/test/redo01.log';
Database altered.
SQL> alter database rename file '/u01/app/oracle/oradata/test/redo02.log' to '/oracledb/test/redo02.log';
Database altered.
SQL> alter database rename file '/u01/app/oracle/oradata/test/redo03.log' to '/oracledb/test/redo03.log';
Database altered.
SQL> alter database open;
Database altered.
***重启验证***
SQL> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> startup
ORACLE instance started.
Total System Global Area 1.0122E+10 bytes
Fixed Size 2237088 bytes
Variable Size 1610616160 bytes
Database Buffers 8489271296 bytes
Redo Buffers 19468288 bytes
Database mounted.
Database opened.
2.alter tablespace方法
该方法，不能移动system表空间，回滚段表空间和临时段表空间的数据文件。
***offline system表空间时报错***
SQL> alter tablespace system offline;
alter tablespace system offline
*
ERROR at line 1:
ORA-01541: system tablespace cannot be brought offline; shut down if necessary
报错：说明system表空间不能offline
***由此说明一下system表空间的特性--不能脱机offline
--不能置为只读read only
--不能重命名
--不能删除
SQL> alter tablespace sysaux offline;
Tablespace altered.
[oracle@test ~]$ cp /oracledb/test/sysaux01.dbf /u01/app/oracle/oradata/test/sysaux01.dbf
SQL> alter tablespace sysaux rename datafile '/oracledb/test/sysaux01.dbf' to '/u01/app/oracle/oradata/test/sysaux01.dbf';
Tablespace altered.
SQL> alter tablespace sysaux online;
Tablespace altered.
***offline UNDO表空间时报错***
SQL> alter tablespace UNDOTBS1 offline;
alter tablespace UNDOTBS1 offline
*
ERROR at line 1:
ORA-30042: Cannot offline the undo tablespace
***offline TEMP表空间时报错***
SQL> alter tablespace TEMP offline;
alter tablespace TEMP offline
*
ERROR at line 1:
ORA-03217: invalid option for alter of TEMPORARY TABLESPACE
#把需要移动的数据文件对应的表空间offline
SQL> alter tablespace USERS offline;
Tablespace altered.
#移动数据文件至目标位置
[oracle@test ~]$ cp /oracledb/test/users01.dbf /u01/app/oracle/oradata/test/users01.dbf
#修改表空间中数据文件的位置
SQL> alter tablespace USERS rename datafile '/oracledb/test/users01.dbf' to '/u01/app/oracle/oradata/test/users01.dbf';
Tablespace altered.
#把表空间online
SQL> alter tablespace users online;
Tablespace altered.
3.总结
alter database方法可以移动任何表空间的数据文件，但其要求数据库必须处于mount状态，故此种方法更适合做整体数据库的迁移。
alter tablespace方法需要数据库处于open状态，表空间在offline的状态下才可更改。但其不能移动system表空间，undo表空间和temp表空间的数据文件，故此种方法更适合于做用户数据文件的迁移。
