关于oracle数据库误删表空间文件后无法登陆sqlplus的解决方法
背景： 今天学习了oracle数据库表空间的创建，于是兴冲冲的跑去创建了两个表空间，文件名分别是是/u01/test/my_01.dbf和/u01/test/my_02.dbf。软件系统：CentOS-6.7-x86_64，linux.x64_11gR2_database。创建命令如下：
create tablespace my_01 logging datafile '/u01/test/my_01.dbf' size 128M
alter tablespace my_01 add datafile '/u01/test/my_01.dbf' size 128M
看着/u01/test/下生成两个表空间文件，欣喜若狂。毕竟是自己创造的。然后，我嫌这两个表空间文件占空间，于是在centos图形界面将其move to trash,效果如下：
当我再次使用sqlplus命令时，发现如下错误：
当看到'/u01/test/my_01.dbf'我就想：莫非跟我删除表空间文件有关吧。。。既然问题来了，就要上网找资料，毕竟rp爆发，找到了原因：在oracle启动后，用户登录时是要将方案中原有的配置信息装载进入，装载过程中有文件未找到，所以就报出错误。感谢这位网友的倾情奉献 http://www.doc88.com/p-634723326544.html
解决过程：
[oracle@jie ~]$ sqlplus /nolog
SQL*Plus: Release 11.2.0.1.0 Production on Mon Feb 29 16:05:31 2016
Copyright (c) 1982, 2009, Oracle. All rights reserved.
SQL> conn /as sysdba
Connected to an idle instance.
SQL> startup
ORACLE instance started.
Total System Global Area 830930944 bytes
Fixed Size 2217912 bytes
Variable Size 507512904 bytes
Database Buffers 318767104 bytes
Redo Buffers 2433024 bytes
Database mounted.
ORA-01157: cannot identify/lock data file 6 - see DBWR trace file --错误信息
ORA-01110: data file 6: '/u01/test/my_01.dbf'
SQL> alter database datafile 6 offline drop; --这里的6是根据上面错误信息里的data file 6
Database altered.
SQL> alter database open resetlogs;
alter database open resetlogs
*
ERROR at line 1:
ORA-01139: RESETLOGS option only valid after an incomplete database recovery
SQL> alter database open;
alter database open
*
ERROR at line 1:
ORA-01157: cannot identify/lock data file 7 - see DBWR trace file
ORA-01110: data file 7: '/u01/test/my_02.dbf'
（因为我有误删了两个表空间文件，所以还有个7要处理，重复上面步骤）
SQL> alter database datafile 7 offline drop;
Database altered.
SQL> alter database open resetlogs;
alter database open resetlogs
*
ERROR at line 1:
ORA-01139: RESETLOGS option only valid after an incomplete database recovery
SQL> alter database open;
Database altered.
SQL> shutdown normal
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> startup mount;
ORACLE instance started.
Total System Global Area 830930944 bytes
Fixed Size 2217912 bytes
Variable Size 507512904 bytes
Database Buffers 318767104 bytes
Redo Buffers 2433024 bytes
Database mounted.
SQL> conn scott
Enter password:
ERROR:
ORA-01033: ORACLE initialization or shutdown in progress
Process ID: 0
Session ID: 0 Serial number: 0
Warning: You are no longer connected to ORACLE.
（重新启动下oracle就好！）
SQL> quit
[oracle@jie ~]$ su - oracle
Password:
[oracle@jie ~]$ sqlplus /nolog
SQL*Plus: Release 11.2.0.1.0 Production on Mon Feb 29 16:44:51 2016
Copyright (c) 1982, 2009, Oracle. All rights reserved.
SQL> conn /as sysdba
Connected.
SQL> startup
ORA-01081: cannot start already-running ORACLE - shut it down first
SQL> shutdown immediate
ORA-01109: database not open
Database dismounted.
ORACLE instance shut down.
SQL> startup
ORACLE instance started.
Total System Global Area 830930944 bytes
Fixed Size 2217912 bytes
Variable Size 507512904 bytes
Database Buffers 318767104 bytes
Redo Buffers 2433024 bytes
Database mounted.
Database opened.
SQL> conn scott
Enter password:
Connected.
至此，问题解决！！