未完全关闭数据库导致ORA-01012: not logged的解决

首先使用SHUTDOWN 没加任何参数方式关闭数据库，在数据库未关闭时CTRL+Z停止执行，退出用SQLPLUS重登陆，出现报错：ORA-01012: not logged on 
SQL> startup
ORA-01012: not logged on
解决 ：
SQL> shutdown abort
ORACLE instance shut down.
[oracle@oracle ~]$ ps -ef
le   11549     1  0 21:51 ?        00:00:00 /u01/app/oracle/product/11.2.0/d
root     11668     1  0 21:53 ?        00:00:00 su - oracle
oracle   11669 11668  0 21:53 ?        00:00:00 -bash
oracle   11853     1  0 22:05 ?        00:00:00 /u01/app/oracle/product/11.2.0/d
oracle   11980 10672  0 22:15 pts/0    00:00:00 ./sqlplus   as sysdba
oracle   12006 11980  0 22:17 ?        00:00:00 oracleorcl2 (DESCRIPTION=(LOCAL=
root     12017  2627  0 22:18 ?        00:00:00 sleep 60
[oracle@oracle ~]$ kill -9 11980
SQL> 已杀死
[oracle@oracle ~]$ sqlplus / as sysdba
SQL*Plus: Release 11.2.0.1.0 Production on Wed Mar 12 22:19:32 2014

Copyright (c) 1982, 2009, Oracle.  All rights reserved.

Connected to an idle instance.

SQL> startup
ORACLE instance started.

Total System Global Area  730714112 bytes
Fixed Size            2216944 bytes
Variable Size          452987920 bytes
Database Buffers      268435456 bytes
Redo Buffers            7073792 bytes
Database mounted.
Database opened.