配置与使用闪回之闪回数据库

闪回数据库

flashback database to timestamp sysdate-1/24

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ERROR at line 1:

ORA-38757: Database must be mounted and not open to FLASHBACK.

 

 

SQL> shutdown immediate

Database closed.

Database dismounted.

ORACLE instance shut down.

SQL> startup mount

ORACLE instance started.

 Total System Global Area  417546240 bytes

Fixed Size                  2228944 bytes

Variable Size             318770480 bytes

Database Buffers           88080384 bytes

Redo Buffers                8466432 bytes

Database mounted.

SQL> flashback database to timestamp sysdate-1/24;

flashback database to timestamp sysdate-1/24

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ERROR at line 1:

ORA-38726: Flashback database logging is not on.

SQL> select flashback_on from v$database;

 

FLASHBACK_ON

------------------

NO

SQL> alter database flashback on;

Database altered.

SQL> flashback database to timestamp sysdate-1/24;

flashback database to timestamp sysdate-1/24

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ERROR at line 1:

ORA-38729: Not enough flashback database log data to do FLASHBACK.

SQL> flashback database to timestamp sysdate-1/1440;

Flashback complete.

SQL> alter database open;    

alter database open

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ERROR at line 1:

ORA-01589: must use RESETLOGS or NORESETLOGS option for database open

SQL> alter database open resetlogs;

Database altered.

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SQL> l

  1*  flashback database to timestamp sysdate-1/24

SQL> flashback database to timestamp sysdate-2/1440;

 

Flashback complete.

 

SQL> flashback database to timestamp sysdate-3/1440;

flashback database to timestamp sysdate-3/1440

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ERROR at line 1:

ORA-38754: FLASHBACK DATABASE not started; required redo log is not available

ORA-38762: redo logs needed for SCN 2178835 to SCN 2178835

ORA-38761: redo log sequence 64 in thread 1, incarnation 2 could not be accessed

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