undo表空间丢失、损坏
1、模拟误删undo表空间 rm -rf undotbs01.dbf 2、 SQL> shutdown immediate ORA-01116: error in opening database file 3 ORA-01110: data file 3: '/u01/app/oracle/oradata/PROD1/undotbs01.dbf' ORA-27041: unable to open file Linux Error: 2: No such file or directory Additional information: 3 SQL> select status from v$instance; STATUS ------------ OPEN SQL> shutdown abort; ORACLE instance shut down. SQL> startup ORACLE instance started. Total System Global Area 849530880 bytes Fixed Size 1348244 bytes Variable Size 499125612 bytes Database Buffers 343932928 bytes Redo Buffers 5124096 bytes Database mounted. ORA