1. alter database open resetlogs；
    2. recover database using backup controfile;
    3. alter database open resetlogs。
    4. alter system set “_allow_resetlogs_corruption”=true scope=spfile;
    5. startup force mount;
    6. alter database open resetlogs;

    1.模拟文件丢失

    1. rm -rf redo0*

    2.关闭数据库进行恢复

    1. SQL> shutdown immediate;                                                                                                         
    2. Database closed.                                                                                                                 
    3. Database dismounted.                                                                                                             
    4. ORACLE instance shut down.

    3.启动mount

    1. SQL>  startup mount;                                                                                                             
    2. ORACLE instance started.                                                                                                         
    4. Total System Global Area  838857584 bytes                                                                                        
    5. Fixed Size                  8901488 bytes                                                                                        
    6. Variable Size             700448768 bytes                                                                                        
    7. Database Buffers          121634816 bytes                                                                                        
    8. Redo Buffers                7872512 bytes                                                                                        
    9. Database mounted.

    4.尝试能否打开数据库

    1. SQL> alter   database  open resetlogs;                                                                                           
    2. alter   database  open resetlogs                                                                                                 
    3. *                                                                                                                                
    4. ERROR at line 1:                                                                                                                 
    5. ORA-01139: RESETLOGS option only valid after an incomplete database recovery

    5.添加隐藏参数

    2. SQL> alter system set "_allow_resetlogs_corruption"=true scope=spfile;                                                           
    4. System altered.

    6.尝试使用控制文件恢复

    1. SQL> recover database using backup controlfile;                                                                                  
    2. ORA-00279: change 5453650 generated at 09/02/2019 21:34:57 needed for thread 1                                                   
    3. ORA-00289: suggestion :                                                                                                          
    4. /opt/oracle/fast_recovery_area/ORCLCDB/archivelog/2019_09_02/o1_mf_1_114_%u_.arc                                                 
    5. ORA-00280: change 5453650 for thread 1 is in sequence #114                                                                       
    8. Specify log: {<RET>=suggested | filename | AUTO | CANCEL}                                                                        
    10. ORA-00308: cannot open archived log                                                                                              
    11. '/opt/oracle/fast_recovery_area/ORCLCDB/archivelog/2019_09_02/o1_mf_1_114_%u_.ar                                                 
    12. c'                                                                                                                               
    13. ORA-27037: unable to obtain file status                                                                                          
    14. Linux-x86_64 Error: 2: No such file or directory                                                                                 
    15. Additional information: 7

    7.一致性关闭，先启动mount，在使用resetlogs启动数据库。

    1. SQL> shutdown immediate;                                                                                                         
    2. ORA-01109: database not open                                                                                                     
    5. Database dismounted.                                                                                                             
    6. ORACLE instance shut down.                                                                                                       
    7. SQL> alter   database  open resetlogs;                                                                                           
    8. alter   database  open resetlogs                                                                                                 
    9. *                                                                                                                                
    10. ERROR at line 1:                                                                                                                 
    11. ORA-01034: ORACLE not available                                                                                                  
    12. Process ID: 0                                                                                                                    
    13. Session ID: 0 Serial number: 0                                                                                                   
    16. SQL> startup mount;                                                                                                              
    17. ORACLE instance started.                                                                                                         
    19. Total System Global Area  838857584 bytes                                                                                        
    20. Fixed Size                  8901488 bytes                                                                                        
    21. Variable Size             700448768 bytes                                                                                        
    22. Database Buffers          121634816 bytes                                                                                        
    23. Redo Buffers                7872512 bytes                                                                                        
    24. Database mounted.                                                                                                                
    25. SQL> alter   database  open resetlogs;                                                                                           
    27. Database altered.

    8.取消隐藏参数，一致性关闭数据库，重新open打开。

    1. SQL> alter system set "_allow_resetlogs_corruption"=false scope=spfile;                                                          
    3. System altered.                                                                                                                  
    4. SQL> shutdown immediate;                                                                                                         
    5. Database closed.                                                                                                                 
    6. Database dismounted.                                                                                                             
    7. ORACLE instance shut down.                                                                                                       
    8. SQL> startup                                                                                                                     
    9. ORACLE instance started.                                                                                                         
    11. Total System Global Area  838857584 bytes                                                                                        
    12. Fixed Size                  8901488 bytes                                                                                        
    13. Variable Size             700448768 bytes                                                                                        
    14. Database Buffers          121634816 bytes                                                                                        
    15. Redo Buffers                7872512 bytes                                                                                        
    16. Database mounted.                                                                                                                
    17. Database opened.                                                                                                                 
    18. SQL>