管理数据文件
一 Creating Datafiles and Adding Datafiles to a Tablespace
1 alter tablespace zx add datafile '/oracle/CRM2/CRM/zx04.dbf' size 1M;
2 alter tablespace ltemp add tempfile '/oracle/CRM2/CRM/ltemp01.dbf' size 200m;
二：Changing Datafile Size
1 开启或禁止数据文件自动扩展
通过查询dba_data_files视图字段autoextensible以确定数据文件是否自动扩展
 select file_id,file_name,tablespace_name,autoextensible from  dba_data_files
   FILE_ID FILE_NAME                      TABLESPACE_NAME                AUT
---------- ------------------------------ ------------------------------ ---
         8 /oracle/CRM2/CRM/zxbig1.dbf    ZXBIGTBS                       NO
         7 /oracle/CRM2/CRM/zx3.dbf       ZX                             NO
         6 /oracle/CRM2/CRM/undotbs2.dbf  UNDOTBS2                       NO
         5 /oracle/CRM2/CRM/zx1.dbf       ZX                             NO
         4 /oracle/CRM2/CRM/users01.dbf   USERS                          YES
         3 /oracle/CRM2/CRM/sysaux01.dbf  SYSAUX                         YES
         2 /oracle/CRM2/CRM/zx2.dbf       ZX                             NO
         1 /oracle/CRM2/CRM/system01.dbf  SYSTEM                         YES
更改数据文件为自动扩展
alter database datafile '/oracle/CRM2/CRM/zx1.dbf' autoextend on;
禁止数据文件的自动扩展
alter database datafile '/oracle/CRM2/CRM/zx1.dbf' autoextend off；
eg：更改数据文件自动扩展
SQL> alter database datafile '/oracle/CRM2/CRM/zx1.dbf' autoextend on;
Database altered.
select file_id,file_name,tablespace_name,autoextensible from dba_data_files
   FILE_ID FILE_NAME                      TABLESPACE_NAME                AUT
---------- ------------------------------ ------------------------------ ---
         8 /oracle/CRM2/CRM/zxbig1.dbf    ZXBIGTBS                       NO
         7 /oracle/CRM2/CRM/zx3.dbf       ZX                             NO
         6 /oracle/CRM2/CRM/undotbs2.dbf  UNDOTBS2                       NO
         5 /oracle/CRM2/CRM/zx1.dbf       ZX                             YES
         4 /oracle/CRM2/CRM/users01.dbf   USERS                          YES
         3 /oracle/CRM2/CRM/sysaux01.dbf  SYSAUX                         YES
         2 /oracle/CRM2/CRM/zx2.dbf       ZX                             NO
         1 /oracle/CRM2/CRM/system01.dbf  SYSTEM                         YES
eg 禁止数据文件自动扩展
SQL> alter database datafile '/oracle/CRM2/CRM/zx1.dbf' autoextend off;
Database altered.
SQL> select file_id,file_name,tablespace_name,autoextensible from dba_data_files;
   FILE_ID FILE_NAME                      TABLESPACE_NAME                AUT
---------- ------------------------------ ------------------------------ ---
         8 /oracle/CRM2/CRM/zxbig1.dbf    ZXBIGTBS                       NO
         7 /oracle/CRM2/CRM/zx3.dbf       ZX                             NO
         6 /oracle/CRM2/CRM/undotbs2.dbf  UNDOTBS2                       NO
         5 /oracle/CRM2/CRM/zx1.dbf       ZX                             NO
         4 /oracle/CRM2/CRM/users01.dbf   USERS                          YES
         3 /oracle/CRM2/CRM/sysaux01.dbf  SYSAUX                         YES
         2 /oracle/CRM2/CRM/zx2.dbf       ZX                             NO
         1 /oracle/CRM2/CRM/system01.dbf  SYSTEM                         YES
2  调整数据文件的大小
语句：alter database datafile  ...... resize xxx
eg 增加数据文件大小
看当前数据文件的大小
SQL> select file_id,file_name,tablespace_name,bytes/1024/1024 ,autoextensible from dba_data_files;
   FILE_ID FILE_NAME                      TABLESPACE_NAME                BYTES/1024/1024 AUT
---------- ------------------------------ ------------------------------ --------------- ---
         8 /oracle/CRM2/CRM/zxbig1.dbf    ZXBIGTBS                                  2048 NO
         7 /oracle/CRM2/CRM/zx3.dbf       ZX                                           1 NO
         6 /oracle/CRM2/CRM/undotbs2.dbf  UNDOTBS2                                   200 NO
         5 /oracle/CRM2/CRM/zx1.dbf       ZX                                         100 NO
         4 /oracle/CRM2/CRM/users01.dbf   USERS                                        5 YES
         3 /oracle/CRM2/CRM/sysaux01.dbf  SYSAUX                                     280 YES
         2 /oracle/CRM2/CRM/zx2.dbf       ZX                                          10 NO
         1 /oracle/CRM2/CRM/system01.dbf  SYSTEM                                     480 YES
增加数据文件/oracle/CRM2/CRM/zx3.dbf为10M;
SQL> alter database datafile '/oracle/CRM2/CRM/zx3.dbf' resize 10M;
Database altered.
SQL> select file_id,file_name,tablespace_name,bytes/1024/1024 ,autoextensible from dba_data_files;
   FILE_ID FILE_NAME                      TABLESPACE_NAME                BYTES/1024/1024 AUT
---------- ------------------------------ ------------------------------ --------------- ---
         8 /oracle/CRM2/CRM/zxbig1.dbf    ZXBIGTBS                                  2048 NO
         7 /oracle/CRM2/CRM/zx3.dbf       ZX                                          10 NO
         6 /oracle/CRM2/CRM/undotbs2.dbf  UNDOTBS2                                   200 NO
         5 /oracle/CRM2/CRM/zx1.dbf       ZX                                         100 NO
         4 /oracle/CRM2/CRM/users01.dbf   USERS                                        5 YES
         3 /oracle/CRM2/CRM/sysaux01.dbf  SYSAUX                                     280 YES
         2 /oracle/CRM2/CRM/zx2.dbf       ZX                                          10 NO
         1 /oracle/CRM2/CRM/system01.dbf  SYSTEM                                     480 YES
  
eg 减小数据文件大小
注意能否减少取决于数据文件当前使用值。
SQL> alter database datafile '/oracle/CRM2/CRM/zx3.dbf' resize 1M;
Database altered.
SQL> select file_id,file_name,tablespace_name,bytes/1024/1024,autoextensible from dba_data_files;
   FILE_ID FILE_NAME                      TABLESPACE_NAME                BYTES/1024/1024 AUT
---------- ------------------------------ ------------------------------ --------------- ---
         8 /oracle/CRM2/CRM/zxbig1.dbf    ZXBIGTBS                                  2048 NO
         7 /oracle/CRM2/CRM/zx3.dbf       ZX                                           1 NO
         6 /oracle/CRM2/CRM/undotbs2.dbf  UNDOTBS2                                   200 NO
         5 /oracle/CRM2/CRM/zx1.dbf       ZX                                         100 NO
         4 /oracle/CRM2/CRM/users01.dbf   USERS                                        5 YES
         3 /oracle/CRM2/CRM/sysaux01.dbf  SYSAUX                                     280 YES
         2 /oracle/CRM2/CRM/zx2.dbf       ZX                                          10 NO
         1 /oracle/CRM2/CRM/system01.dbf  SYSTEM                                     480 YES
三 更改数据文件可用性
那些情况需要我们offline数据文件
a 执行一个离线备份
b 重命名或者迁移数据文件，必须先离线数据文件
c 数据文件丢失或者损坏，打开数据之前，这些文件必须offline
注意，对只读表空间的数据文件offline后online并不会影响表空间的只读状态。
1 归档模式下offline或者online 数据文件
语句 alter database datafile ........ online|offline;
不过注意，offline的数据online的时候需要recover
eg
SQL> select file#,name,status from v$datafile;
     FILE# NAME                                     STATUS
---------- ---------------------------------------- -------
         1 /oracle/CRM2/CRM/system01.dbf            SYSTEM
         2 /oracle/CRM2/CRM/zx2.dbf                 ONLINE
         3 /oracle/CRM2/CRM/sysaux01.dbf            ONLINE
         4 /oracle/CRM2/CRM/users01.dbf             ONLINE
         5 /oracle/CRM2/CRM/zx1.dbf                 ONLINE
         6 /oracle/CRM2/CRM/undotbs2.dbf            ONLINE
         7 /oracle/CRM2/CRM/zx3.dbf                 ONLINE
         8 /oracle/CRM2/CRM/zxbig1.dbf              ONLINE
8 rows selected.
SQL> alter database datafile '/oracle/CRM2/CRM/zx3.dbf' offline;
Database altered.
SQL> select file#,name,status from v$datafile;
     FILE# NAME                                     STATUS
---------- ---------------------------------------- -------
         1 /oracle/CRM2/CRM/system01.dbf            SYSTEM
         2 /oracle/CRM2/CRM/zx2.dbf                 ONLINE
         3 /oracle/CRM2/CRM/sysaux01.dbf            ONLINE
         4 /oracle/CRM2/CRM/users01.dbf             ONLINE
         5 /oracle/CRM2/CRM/zx1.dbf                 ONLINE
         6 /oracle/CRM2/CRM/undotbs2.dbf            ONLINE
         7 /oracle/CRM2/CRM/zx3.dbf                 RECOVER
         8 /oracle/CRM2/CRM/zxbig1.dbf              ONLINE
8 rows selected.
SQL> alter database datafile '/oracle/CRM2/CRM/zx3.dbf' online; 注意这里，不能直接online，上面status字段已经提示需要recover
alter database datafile '/oracle/CRM2/CRM/zx3.dbf' online
*
ERROR at line 1:
ORA-01113: file 7 needs media recovery
ORA-01110: data file 7: '/oracle/CRM2/CRM/zx3.dbf'

SQL> recover datafile 7;
Media recovery complete.
SQL> alter database datafile 7 online;
Database altered.
SQL> select file#,name,status from v$datafile;
     FILE# NAME                                     STATUS
---------- ---------------------------------------- -------
         1 /oracle/CRM2/CRM/system01.dbf            SYSTEM
         2 /oracle/CRM2/CRM/zx2.dbf                 ONLINE
         3 /oracle/CRM2/CRM/sysaux01.dbf            ONLINE
         4 /oracle/CRM2/CRM/users01.dbf             ONLINE
         5 /oracle/CRM2/CRM/zx1.dbf                 ONLINE
         6 /oracle/CRM2/CRM/undotbs2.dbf            ONLINE
         7 /oracle/CRM2/CRM/zx3.dbf                 ONLINE
         8 /oracle/CRM2/CRM/zxbig1.dbf              ONLINE
2 同时更改表空间所有数据文件状态
语句
alter tablespace ..... datafile   offline|online
alter tablespace ...... tempfile  offline|online
注意
a 该语句影响表空间的所有数据文件，而不影响表空间的状态。
b 对于离线system，undo，默认临时表空间所有数据文件时，数据库必须mount。而其它表空间数据文件的离线无限制，mount open状态都可以。
eg ：测试离线表空间所有数据文件而表空间状态不变
当前表空间状态
SQL> select tablespace_name,status from dba_tablespaces;
TABLESPACE_NAME                STATUS
------------------------------ ---------
SYSTEM                         ONLINE
SYSAUX                         ONLINE
TEMP                           ONLINE
USERS                          ONLINE
UNDOTBS2                       ONLINE
ZX                             ONLINE
ZXBIGTBS                       ONLINE
LTEMP1                         ONLINE
LTEMP2                         ONLINE
离线zx表空间所有数据文件
SQL> alter tablespace zx datafile offline;
Tablespace altered.
SQL> select file#,name,status from v$datafile;
     FILE# NAME                           STATUS
---------- ------------------------------ -------
         1 /oracle/CRM2/CRM/system01.dbf  SYSTEM
         2 /oracle/CRM2/CRM/zx2.dbf       RECOVER
         3 /oracle/CRM2/CRM/sysaux01.dbf  ONLINE
         4 /oracle/CRM2/CRM/users01.dbf   ONLINE
         5 /oracle/CRM2/CRM/zx1.dbf       RECOVER
         6 /oracle/CRM2/CRM/undotbs2.dbf  ONLINE
         7 /oracle/CRM2/CRM/zx3.dbf       RECOVER
         8 /oracle/CRM2/CRM/zxbig1.dbf    ONLINE
SQL> select tablespace_name,status from dba_tablespaces;
TABLESPACE_NAME                STATUS
------------------------------ ---------
SYSTEM                         ONLINE
SYSAUX                         ONLINE
TEMP                           ONLINE
USERS                          ONLINE
UNDOTBS2                       ONLINE
ZX                             ONLINE
ZXBIGTBS                       ONLINE
LTEMP1                         ONLINE
LTEMP2                         ONLINE
eg：测试system表空间所有数据文件和undo表空间所有数据文件只能在数据库mount状态下离线。
SQL> alter tablespace system datafile offline;
alter tablespace system datafile offline
*
ERROR at line 1:
ORA-01541: system tablespace cannot be brought offline; shut down if necessary

SQL> alter tablespace undotbs2 datafile offline;
alter tablespace undotbs2 datafile offline
*
ERROR at line 1:
ORA-30021: Operation not allowed on undo tablespace

SQL> startup force mount;
ORACLE instance started.
Total System Global Area  322961408 bytes
Fixed Size                  2020480 bytes
Variable Size              96471936 bytes
Database Buffers          218103808 bytes
Redo Buffers                6365184 bytes
Database mounted.
SQL> alter tablespace system datafile offline;
Tablespace altered.
SQL> alter tablespace undotbs2 datafile offline;
Tablespace altered.
SQL> select file#,name,status from v$datafile;
     FILE# NAME                                     STATUS
---------- ---------------------------------------- -------
         1 /oracle/CRM2/CRM/system01.dbf            SYSOFF
         2 /oracle/CRM2/CRM/zx2.dbf                 ONLINE
         3 /oracle/CRM2/CRM/sysaux01.dbf            ONLINE
         4 /oracle/CRM2/CRM/users01.dbf             ONLINE
         5 /oracle/CRM2/CRM/zx1.dbf                 ONLINE
         6 /oracle/CRM2/CRM/undotbs2.dbf            RECOVER
         7 /oracle/CRM2/CRM/zx3.dbf                 ONLINE
         8 /oracle/CRM2/CRM/zxbig1.dbf              ONLINE
四 重命名和迁移数据文件
注意：对于重命名或者迁移系统表空间数据文件，默认临时表空间数据文件、或者还原表空间数据文件则必须使用alter database 方式。
重命名单个表空间的数据文件步骤:
1 normal离线表空间的所有数据文件
alter tablespace zx offline normal；
2 在操作系统上更改数据文件名
3 使用alter tablespace ........rename datafile 语句改变数据文件名字
4 online表空间，查询相应视图确认更改效果
--------------------------------------------------------------------------
迁移单个表空间数据文件的步骤:
1 normal离线表空间的所有数据文件
2 在操作系统上拷贝数据文件到目标位置
3 使用alter tablespace ........rename datafile 语句改变数据文件位置。
4 online表空间，查询相应视图确认更改效果
---------------------------------------------------------------------------
重命名或者迁移多个表空间数据文件的步骤：
1 确保数据库处于mount状态
2 基于操作系统拷贝或者重命名数据文件
3 使用alter database语句更改文件位置或者名字。
-----------------------------------------------------------------------------
以下三个例子分别展示如何操作：
eg1：更改zx表空间中所有数据文件名字
查询zx表空间中所有数据文件名字：
select tb.name as tablespace_name,df.file#,df.name as datafile,df.status from v$tablespace tb,v$datafile df where tb.ts#=df.ts#
TABLESPACE_NAME                     FILE# DATAFILE                                 STATUS
------------------------------ ---------- ---------------------------------------- -------
SYSTEM                                  1 /oracle/CRM2/CRM/system01.dbf            SYSTEM
SYSAUX                                  3 /oracle/CRM2/CRM/sysaux01.dbf            ONLINE
USERS                                   4 /oracle/CRM2/CRM/users01.dbf             ONLINE
UNDOTBS2                                6 /oracle/CRM2/CRM/undotbs2.dbf            ONLINE
ZX                                      5 /oracle/CRM2/CRM/zx1.dbf                 ONLINE
ZX                                      7 /oracle/CRM2/CRM/zx3.dbf                 ONLINE
ZX                                      2 /oracle/CRM2/CRM/zx2.dbf                 ONLINE
ZXBIGTBS                                8 /oracle/CRM2/CRM/zxbig1.dbf              ONLINE
normal离线zx表空间：
SQL> alter tablespace zx offline normal;
Tablespace altered.
操作系统上重命名zx表空间：
SQL> host;
[oracle@oracle ~]$ mv /oracle/CRM2/CRM/zx1.dbf /oracle/CRM2/CRM/zxa.dbf
[oracle@oracle ~]$ mv /oracle/CRM2/CRM/zx2.dbf /oracle/CRM2/CRM/zxb.dbf
[oracle@oracle ~]$ mv /oracle/CRM2/CRM/zx3.dbf /oracle/CRM2/CRM/zxc.dbf
[oracle@oracle ~]$ ls -l /oracle/CRM2/CRM/zx*
-rw-r----- 1 oracle oinstall  104865792 Nov  2 20:18 /oracle/CRM2/CRM/zxa.dbf
-rw-r----- 1 oracle oinstall   10493952 Nov  2 20:18 /oracle/CRM2/CRM/zxb.dbf
-rw-r----- 1 oracle oinstall 2147491840 Nov  2 19:47 /oracle/CRM2/CRM/zxbig1.dbf
-rw-r----- 1 oracle oinstall    1056768 Nov  2 20:18 /oracle/CRM2/CRM/zxc.dbf
使用alter tablespace ........rename datafile 语句改变数据文件名字：
语句:alter tablespace zx
               rename datafile '/oracle/CRM2/CRM/zx1.dbf',
                                           '/oracle/CRM2/CRM/zx2.dbf',
                                           '/oracle/CRM2/CRM/zx3.dbf'
                        to               '/oracle/CRM2/CRM/zxa.dbf',
                                          '/oracle/CRM2/CRM/zxb.dbf',
                                          '/oracle/CRM2/CRM/zxc.dbf' ;
         
SQL> alter tablespace zx
  2                 rename datafile '/oracle/CRM2/CRM/zx1.dbf',
  3                                            '/oracle/CRM2/CRM/zx2.dbf',
  4                                            '/oracle/CRM2/CRM/zx3.dbf'
  5                              to          '/oracle/CRM2/CRM/zxa.dbf',
  6                                           '/oracle/CRM2/CRM/zxb.dbf',
  7                                           '/oracle/CRM2/CRM/zxc.dbf' ;
Tablespace altered.
online表空间并检查更改效果如下：
SQL> alter tablespace zx online;
Tablespace altered.
SQL> select tb.name as tablespace_name,df.file#,df.name as datafile,df.status from v$tablespace tb,v$datafile df where tb.ts#=df.ts#;
TABLESPACE_NAME                     FILE# DATAFILE                                 STATUS
------------------------------ ---------- ---------------------------------------- -------
SYSTEM                                  1 /oracle/CRM2/CRM/system01.dbf            SYSTEM
SYSAUX                                  3 /oracle/CRM2/CRM/sysaux01.dbf            ONLINE
USERS                                   4 /oracle/CRM2/CRM/users01.dbf             ONLINE
UNDOTBS2                                6 /oracle/CRM2/CRM/undotbs2.dbf            ONLINE
ZX                                      5 /oracle/CRM2/CRM/zxa.dbf                 ONLINE
ZX                                      7 /oracle/CRM2/CRM/zxc.dbf                 ONLINE
ZX                                      2 /oracle/CRM2/CRM/zxb.dbf                 ONLINE
ZXBIGTBS                                8 /oracle/CRM2/CRM/zxbig1.dbf              ONLINE
eg2:迁移表空间zx所有数据文件到位置/oracle/CRM2/
查询zx表空间中所有数据文件名字：
select tablespace_name,file_id,file_name,status from dba_data_files where tablespace_name like 'ZX'
TABLESPACE_NAME                   FILE_ID FILE_NAME                      STATUS
------------------------------ ---------- ------------------------------ ---------
ZX                                      7 /oracle/CRM2/CRM/zxc.dbf       AVAILABLE
ZX                                      5 /oracle/CRM2/CRM/zxa.dbf       AVAILABLE
ZX                                      2 /oracle/CRM2/CRM/zxb.dbf       AVAILABLE
normal离线zx表空间：
SQL> alter tablespace zx offline normal;
Tablespace altered.
SQL> select file#,name,status from v$datafile;
     FILE# NAME                           STATUS
---------- ------------------------------ -------
         1 /oracle/CRM2/CRM/system01.dbf  SYSTEM
         2 /oracle/CRM2/CRM/zxb.dbf       OFFLINE
         3 /oracle/CRM2/CRM/sysaux01.dbf  ONLINE
         4 /oracle/CRM2/CRM/users01.dbf   ONLINE
         5 /oracle/CRM2/CRM/zxa.dbf       OFFLINE
         6 /oracle/CRM2/CRM/undotbs2.dbf  ONLINE
         7 /oracle/CRM2/CRM/zxc.dbf       OFFLINE
         8 /oracle/CRM2/CRM/zxbig1.dbf    ONLINE
在操作系统上拷贝数据文件到目标位置：
SQL> host;
[oracle@oracle ~]$ cp /oracle/CRM2/CRM/zx*.dbf /oracle/CRM2/
[oracle@oracle ~]$ ls -l /oracle/CRM2/
total 2213032
-rw-r----- 1 oracle oinstall  104865792 Nov  2 22:37 zxa.dbf
-rw-r----- 1 oracle oinstall   10493952 Nov  2 22:37 zxb.dbf
-rw-r----- 1 oracle oinstall    1056768 Nov  2 22:39 zxc.dbf
使用alter tablespace ........rename datafile 语句改变数据文件位置
语句：alter tablespace zx
                           rename datafile  '/oracle/CRM2/CRM/zxa.dbf',
                                                       '/oracle/CRM2/CRM/zxb.dbf',
                                                       '/oracle/CRM2/CRM/zxc.dbf'
                                                to   '/oracle/CRM2/zxa.dbf',
                                                       '/oracle/CRM2/zxb.dbf',
                                                      '/oracle/CRM2/zxc.dbf';
SQL> alter tablespace zx
  2            rename datafile  '/oracle/CRM2/CRM/zxa.dbf',
  3                                         '/oracle/CRM2/CRM/zxb.dbf',
  4                                         '/oracle/CRM2/CRM/zxc.dbf'
  5                         to            '/oracle/CRM2/zxa.dbf',
  6                                         '/oracle/CRM2/zxb.dbf',
  7                                        '/oracle/CRM2/zxc.dbf';
Tablespace altered.
online表空间，查询相应视图确认更改效果:
select tablespace_name,file_id,file_name,status from dba_data_files where tablespace_name like 'ZX'
TABLESPACE_NAME                   FILE_ID FILE_NAME                      STATUS
------------------------------ ---------- ------------------------------ ---------
ZX                                      7 /oracle/CRM2/zxc.dbf           AVAILABLE
ZX                                      5 /oracle/CRM2/zxa.dbf           AVAILABLE
ZX                                      2 /oracle/CRM2/zxb.dbf           AVAILABLE
eg3：移动system表空间数据文件和更改数据文件名字
启动数据库到mount状态：
SQL> startup force mount;
ORACLE instance started.
Total System Global Area  322961408 bytes
Fixed Size                  2020480 bytes
Variable Size              96471936 bytes
Database Buffers          218103808 bytes
Redo Buffers                6365184 bytes
Database mounted.
拷贝数据文件到目标位置：
SQL> host;
[oracle@oracle ~]$ cp /oracle/CRM2/CRM/system01.dbf  /oracle/CRM2/
[oracle@oracle ~]$ ls -l /oracle/CRM2
total 2705044
-rw-r----- 1 oracle oinstall  503324672 Nov  2 23:17 system01.dbf
通过alter database rename file .....to 移动system表空间位置：
alter database rename file '/oracle/CRM2/CRM/system01.dbf'  to '/oracle/CRM2/system01.dbf';
启动数据库到open状态并确认更改有效：
SQL> alter  database open;
Database altered.
SQL> col name for a30
SQL> select file#,name,status from v$datafile;
     FILE# NAME                           STATUS
---------- ------------------------------ -------
         1 /oracle/CRM2/system01.dbf      SYSTEM
         2 /oracle/CRM2/zxb.dbf           ONLINE
         3 /oracle/CRM2/CRM/sysaux01.dbf  ONLINE
         4 /oracle/CRM2/CRM/users01.dbf   ONLINE
         5 /oracle/CRM2/zxa.dbf           ONLINE
         6 /oracle/CRM2/CRM/undotbs2.dbf  ONLINE
         7 /oracle/CRM2/zxc.dbf           ONLINE
         8 /oracle/CRM2/CRM/zxbig1.dbf    ONLINE

更改system表空间数据文件的名字：
SQL> startup force mount;
ORACLE instance started.
Total System Global Area  322961408 bytes
Fixed Size                  2020480 bytes
Variable Size              96471936 bytes
Database Buffers          218103808 bytes
Redo Buffers                6365184 bytes
Database mounted.
SQL> host;
[oracle@oracle ~]$ mv /oracle/CRM2/system01.dbf  /oracle/CRM2/system1.dbf
[oracle@oracle ~]$ ls /oracle/CRM2/
CRM  ERP  system1.dbf  zxa.dbf  zxb.dbf  zxbig1.dbf  zxc.dbf
SQL> alter database rename file '/oracle/CRM2/system01.dbf' to '/oracle/CRM2/system1.dbf';
Database altered.
SQL> alter  database open;
Database altered.
SQL> select file#,name,status from v$datafile;
     FILE# NAME                           STATUS
---------- ------------------------------ -------
         1 /oracle/CRM2/system1.dbf       SYSTEM
         2 /oracle/CRM2/zxb.dbf           ONLINE
         3 /oracle/CRM2/CRM/sysaux01.dbf  ONLINE
         4 /oracle/CRM2/CRM/users01.dbf   ONLINE
         5 /oracle/CRM2/zxa.dbf           ONLINE
         6 /oracle/CRM2/CRM/undotbs2.dbf  ONLINE
         7 /oracle/CRM2/zxc.dbf           ONLINE
         8 /oracle/CRM2/CRM/zxbig1.dbf    ONLINE
五  Dropping Datafiles
语句：alter tablespace xxx drop datafile 'xxxxxxxxxx';
      alter tablespace xxx drop tempfile 'xxxxxxxxxxxx';
restrictions for drop datafile
1 数据库必须open
2 system表空间的数据文件不能drop
3 如果表空间离线，则数据文件不能drop
4 如果表空间有一个数据文件，则该数据文件不能drop
5 对于大表空间drop datafile语句不适用。
eg1大表空间数据文件drop
 select tablespace_name,file_name,autoextensible from dba_data_files
TABLESPACE_NAME                FILE_NAME                      AUT
------------------------------ ------------------------------ ---
ZXBIGTBS                       /oracle/CRM2/CRM/zxbig1.dbf    NO
ZX                             /oracle/CRM2/zxc.dbf           NO
UNDOTBS2                       /oracle/CRM2/CRM/undotbs2.dbf  NO
ZX                             /oracle/CRM2/zxa.dbf           NO
USERS                          /oracle/CRM2/CRM/users01.dbf   YES
SYSAUX                         /oracle/CRM2/CRM/sysaux01.dbf  YES
ZX                             /oracle/CRM2/zxb.dbf           NO
SYSTEM                         /oracle/CRM2/system1.dbf       YES
SQL> alter tablespace zxbigtbs drop datafile '/oracle/CRM2/CRM/zxbig1.dbf ';
alter tablespace zxbigtbs drop datafile '/oracle/CRM2/CRM/zxbig1.dbf '
*
ERROR at line 1:
ORA-01565: error in identifying file '/oracle/CRM2/CRM/zxbig1.dbf '
eg2:测试表空间只有一个数据文件能不能drop
select tablespace_name,file_name,autoextensible from dba_data_files
TABLESPACE_NAME                FILE_NAME                      AUT
------------------------------ ------------------------------ ---
ZXBIGTBS                       /oracle/CRM2/CRM/zxbig1.dbf    NO
ZX                             /oracle/CRM2/zxc.dbf           NO
UNDOTBS2                       /oracle/CRM2/CRM/undotbs2.dbf  NO
ZX                             /oracle/CRM2/zxa.dbf           NO
USERS                          /oracle/CRM2/CRM/users01.dbf   YES
SYSAUX                         /oracle/CRM2/CRM/sysaux01.dbf  YES
ZX                             /oracle/CRM2/zxb.dbf           NO
SYSTEM                         /oracle/CRM2/system1.dbf       YES
SQL> alter tablespace users drop datafile '/oracle/CRM2/CRM/users01.dbf';
alter tablespace users drop datafile '/oracle/CRM2/CRM/users01.dbf'
*
ERROR at line 1:
ORA-03261: the tablespace USERS has only one file
eg3：测试表空间离线，则数据文件不能删除
SQL> alter tablespace zx offline;
Tablespace altered.
SQL> alter tablespace zx drop datafile '/oracle/CRM2/zxc.dbf';
alter tablespace zx drop datafile '/oracle/CRM2/zxc.dbf'
*
ERROR at line 1:
ORA-03264: cannot drop offline datafile of locally managed tablespace
eg4：要删除数据文件，数据库必须open
SQL> select open_mode from v$database;
OPEN_MODE
----------
MOUNTED
SQL> alter tablespace  zx drop datafile '/oracle/CRM2/zxc.dbf';
alter tablespace  zx drop datafile '/oracle/CRM2/zxc.dbf'
*
ERROR at line 1:
ORA-01109: database not open
eg5 system表空间数据文件不能drop
SQL> alter tablespace system drop datafile '/oracle/CRM2/system1.dbf ';
alter tablespace system drop datafile '/oracle/CRM2/system1.dbf '
*
ERROR at line 1:
ORA-01541: system tablespace cannot be brought offline; shut down if necessary