[Oracle 11g] Oracle 11g에서 ORA-01033 ORACLE initialization or shutdown in progress Error

Symptom(징후)
오라클 접속 시 ORA-01033 ORACLE initialization or shutdown in progress 에러 발생

Solution(해결)
C:\app\series7\product\11.2.0\dbhome_1\BIN> sqlplus sys/password as sysdba
SQL> recover database
SQL> alter database open
SQL> shutdown immediate
SQL> startup

위 명령어를 입력 중에
ORA-01157: cannot identify/lock data file 6 - see DBWR trace file
ORA-01110: data file 6: 'C:\SOFTWAREAG8\COMMON\DB\SCRIPTS\ORACLE\STORAGE\25\CREATE\ORCL\DATAFILE\O1_MF_WEBMDATA_9Y5P9KMP_.DBF' 에러가 발생되면

SQL> alter database datafile 'C:\SOFTWAREAG8\COMMON\DB\SCRIPTS\ORACLE\STORAGE\25\CREATE\ORCL\DATAFILE\O1_MF_WEBMDATA_9Y5P9KMP_.DBF' offline drop;

Reference(참조)
ORA-01033: ORACLE initialization or shutdown in progress - 
http://purplike.tistory.com/309

ORA-01157: cannot identify/lock data file 6 - see DBWR trace file ORA-01110: data file 6: '/opt/oracle/db02/nms_index.dbf' - 

http://anuragkumarjoy.blogspot.kr/2013/11/ora-01157-cannot-identifylock-data-file.html