实验-闪回数据库

一、打开闪回数据库

SQL> select name,log_mode from v$database;

NAME      LOG_MODE
--------- ------------
ORCL      NOARCHIVELOG
SQL> select flashback_on from v$database;

FLASHBACK_ON
-------
NO

Connected to Oracle Database 10g Enterprise Edition Release 10.2.0.4.0
Connected as SYS

档日志的路径

alter system set log_archive_dest_1=‘location=D:\oracle\product\10.2.0\flash_recovery_area\ORCL\ONLINELOG‘;

alter system set log_archive_dest_2=‘location=D:\oracle\product\10.2.0\flash_recovery_area\ORCL\LOG2‘;

查看结果

show parameter log_archive_dest;

SQL> show parameter log_archive_dest;

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
log_archive_dest                     string
log_archive_dest_1                   string      location=D:\oracle\product\10.2.0\flash_recovery_area\ORCL\ONLINELOG
log_archive_dest_10                  string
log_archive_dest_2                   string      location=D:\oracle\product\10.2.0\flash_recovery_area\ORCL\LOG2
log_archive_dest_3                   string
log_archive_dest_4                   string
log_archive_dest_5                   string
log_archive_dest_6                   string
log_archive_dest_7                   string
log_archive_dest_8                   string
log_archive_dest_9                   string   

关闭数据库

shutdown immediate

启动数据mount状态：

set ORACLE_SID=ORCL

SQL> startup mount;

修改数据库为归档模式：

SQL> alter database archivelog;

打开数据库，查询：

SQL> alter database open;

修改日志文件命名格式：

SQL> alter system set log_archive_max_processes = 5;

SQL> alter system set log_archive_format = "archive_%t_%s_%r.log" scope=spfile;

检查是否成功

SQL> archive log list;
数据库日志模式            存档模式
自动存档             启用
存档终点            D:\oracle\product\10.2.0\flash_recovery_area\ORCL\LOG2
最早的联机日志序列     6223
下一个存档日志序列   6225
当前日志序列           6225

切换一下当前日志 归档当前的重做日志文件

SQL> ALTER SYSTEM ARCHIVE LOG CURRENT;

系统已更改。

设置闪回区大小：

SQL> alter system set db_recovery_file_dest_size=10g scope=spfile;

设置闪回区位置：

SQL> alter system set db_recovery_file_dest=‘D:\oracle\product\10.2.0\flash_recovery_area\‘ scope=spfile;

设置闪回目标为2天，以分钟为单位，每天为1440分钟：

SQL> alter system set db_flashback_retention_target=2880 scope=spfile;

SQL> shutdown immediate;
SQL> startup mount;
SQL> alter database flashback on;
SQL> alter database open;

SQL> select flashback_on from v$database;

FLASHBACK_ON
----------
YES

alter user scott account unlock;

连接SCOTT用户

Connected to Oracle Database 10g Enterprise Edition Release 10.2.0.4.0
Connected as scott

删除表

SQL> drop table emp;

Table dropped

查看当前的SCN

select dbms_flashback.get_system_change_number from dual;

恢复到最老的SCN

SQL> select * from v$flashback_database_log;

OLDEST_FLASHBACK_SCN OLDEST_FLASHBACK_TIME RETENTION_TARGET FLASHBACK_SIZE ESTIMATED_FLASHBACK_SIZE
-------------------- --------------------- ---------------- -------------- ------------------------
           159498340 2015/10/8 20:06:07                2880       15941632                        0

闪回操作

shutdown immediate;
startup mount;
flashback database to scn 159498340;
alter database open resetlogs;
----
conn scott/tiger;
SQL> select * from tab;

TNAME                          TABTYPE  CLUSTERID
------------------------------ ------- ----------
DEPT                           TABLE
EMP                            TABLE
BONUS                          TABLE
SALGRADE                       TABLE   

EMP表恢复成功

SQL> shutdown immediate;
SQL> startup mount;
SQL> alter database flashback off;
SQL> alter database open;

版权声明：本文为博主原创文章，未经博主允许不得转载。如果有需要转载请联系[email protected]