[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>