如果拥有一个冷备份，但是缺失了其中的一个数据文件，但是存在所有的归档，应该如何恢复数据文件。

 动手试一下，大概就是如下步骤:

[oracle@jumper eygle]$ sqlplus "/ as sysdba"

SQL*Plus: Release 9.2.0.4.0 - Production on Sun Aug 20 01:22:50 2006

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

Connected to an idle instance.

SQL> startup mount
ORACLE instance started.

Total System Global Area  252777592 bytes
Fixed Size                   451704 bytes
Variable Size             134217728 bytes
Database Buffers          117440512 bytes
Redo Buffers                 667648 bytes
Database mounted.

SQL> alter database open;
alter database open
*
ERROR at line 1:
ORA-01157: cannot identify/lock data file 3 - see DBWR trace file
ORA-01110: data file 3: '/opt/oracle/oradata/eygle/eygle02.dbf'

SQL> alter database create datafile 3 as '/opt/oracle/oradata/eygle/eygle02.dbf';

Database altered.

SQL> select name from v$datafile;

NAME
-------------------------------------------------------
/opt/oracle/oradata/eygle/system01.dbf
/opt/oracle/oradata/eygle/undotbs01.dbf
/opt/oracle/oradata/eygle/eygle02.dbf
/opt/oracle/oradata/eygle/eygle01.dbf

SQL> alter database open;
alter database open
*
ERROR at line 1:
ORA-01113: file 3 needs media recovery
ORA-01110: data file 3: '/opt/oracle/oradata/eygle/eygle02.dbf'

SQL> recover datafile 3;
Media recovery complete.
SQL> alter database open;

Database altered.

SQL>