????Flashback Database?????????
?????????????????????????????????????????????????????????????????????????????????????????????????????????У????????????????????????????????????????????????????????????????????ù鵵?????redo????????????????????????軹???????????????????д?????????????????????????
??????????????????????????????????“?????????”?У????????д??????Recovery Writer??RVWR???????????????????????????????????????????????????????????С?
?????????????????????????
????db_recovery_file_dest  ????????????·??
????db_recovery_file_dest_size  ??????????????С
????db_flashback_retention_target  ?????????????????????λ??????
??????????????????鵵????
????????鵵
????1??SQL> alter system set  log_archive_dest_1='location=+oradg/b1/recovery/' scope=both;
????2??SQL> shutdown immediate
????3??SQL>  startup mount
????4??SQL> alter database archivelog;
????5??SQL> alter database open;
????6??SQL> archive log list
????????????????С??·??????????????

 

SQL> alter system set db_recovery_file_dest_size=5G;
System altered.
SQL> alter system set db_recovery_file_dest='+ORADG';
System altered.
SQL> alter system set db_flashback_retention_target=2880;
System altered.
???????????
SQL> startup mount exclusive
SQL> alter database flashback on;
Database altered.
SQL> select flashback_on from v$database;
FLASHBACK_ON
------------------
YES

??????????????

SQL> startup mount exclusive
ORACLE instance started.
Total System Global Area  839282688 bytes
Fixed Size                  2217992 bytes
Variable Size             557844472 bytes
Database Buffers          276824064 bytes
Redo Buffers                2396160 bytes
Database mounted.
SQL> ?alter database flashback off;
Database altered.
SQL> alter database open ;
Database altered.
SQL> alter system set db_recovery_file_dest='';
System altered.
 ?????????????????
????1??????????
????2??????????mount??[exclusive??]
????3???????????????SCN?????
????4?????resetlogs???????
?????????????????
????1??sqlplus?????SCN????
????FLASHBACK  DATABASE [<database_name>]  TO  SCN <system_change_number>
????2??sqlplus?????????????
????FLASHBACK  DATABASE [<database_name>]  TO  TIMESTMP <system_timestamp_value>
????3??sqlplus?????????????
????FLASHBACK  DATABASE [<database_name>]  TO  RESTORE POINT <restore_point_name>
????4??RMAN?????????????
????RMAN> FLASHBACK DATABASE TO TIME = "TO_DATE('2013-10-10 19:25:21'??'YYYY-MM-DD HH24:MI:SS')";
????5??RMAN?????SCN????
????RMAN> FLASHBACK DATABASE TO SCN=1121679;
????6??RMAN???????鵵???
????RMAN> FLASHBACK DATABASE TO SEQUENCE=56 THREAD=1;
????????????????????
 
????12????
???????????????????????漰???????????????????SPASVOС??(021-61079698-8054)?????????????????????????