[root@aa ~]# su - oracle
[oracle@aa ~]$ echo $ORACLE_SID
orcl
[oracle@aa ~]$ sqlplus / as sysdba
SQL*Plus: Release 10.2.0.1.0 - Production on Thu Jul 7 19:45:34 2011
Copyright (c) 1982, 2005, Oracle. All rights reserved.
Connected to an idle instance.
SQL> startup
ORACLE instance started.
Total System Global Area 838860800 bytes
Fixed Size 1222192 bytes
Variable Size 390072784 bytes
Database Buffers 440401920 bytes
Redo Buffers 7163904 bytes
Database mounted.
Database opened.
SQL> create tablespace text1 datafile '/oracle/oradata/orcl/text1.dbf' size 10m;
Tablespace created.
SQL> create user t identified by t default tablespace text1;
User created.
SQL> grant connect,resource to t;
Grant succeeded.
SQL> conn t/t
Connected.
SQL> create table t1 (id number);
Table created.
SQL> insert into t1 values (1);
1 row created.
SQL> select * from t1;
ID
----------
1
SQL> commit;
Commit complete.
----------------------------------------------------
[oracle@aa ~]$ cd /oracle/oradata/orcl/
[oracle@aa orcl]$ ls
abctbs.dbf example01.dbf sysaux01.dbf undotbs01.dbf
control01.ctl redo01.log system01.dbf undotbs02_1.dbf
control02.ctl redo02.log temp01.dbf undotbs02.dbf
control03.ctl redo03.log text1.dbf users01.dbf
[oracle@aa orcl]$ rm text1.dbf
[oracle@aa orcl]$
-------------------------------------------------------
SQL> conn / as sysdba
SQL> shutdown immediate
ORA-01116: error in opening database file 9
ORA-01110: data file 9: '/oracle/oradata/orcl/text1.dbf'
ORA-27041: unable to open file
Linux Error: 2: No such file or directory
Additional information: 3
SQL> shutdown abort
ORACLE instance shut down.
SQL> startup nomount
Variable Size 394267088 bytes
Database Buffers 436207616 bytes
SQL> alter database mount;
Database altered.
SQL> alter database open;
alter database open
*
ERROR at line 1:
ORA-01157: cannot identify/lock data file 9 - see DBWR trace file
SQL> alter database datafile 9 offline;
SQL> alter database create datafile 9;
SQL> set autorecovery on;
SQL> recover datafile 9;
Media recovery complete.
SQL> alter database datafile 9 online;