oracle 快照数据库和物理备库的转换

　　SQL> select * from v$version;
　　BANNER
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Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - 64bit Production
PL/SQL Release 11.2.0.2.0 - Production
CORE 11.2.0.2.0 Production
TNS for Linux: Version 11.2.0.2.0 - Production
NLSRTL Version 11.2.0.2.0 - Production
　　SQL> select open_mode,database_role from v$database;
　　OPEN_MODE      DATABASE_ROLE
-------------------- ----------------
READ ONLY WITH APPLY PHYSICAL STANDBY
首先停止redo apply进程;
SQL> alter database recover managed standby database cancel;
　　Database altered.
然后关闭数据库，并启动数据库到mount状态;
SQL> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> startup mount;
ORACLE instance started.
　　Total System Global Area  534462464 bytes
Fixed Size       2228200 bytes
Variable Size     423624728 bytes
Database Buffers   100663296 bytes
Redo Buffers      7946240 bytes
Database mounted.
然后转换到 快照数据库;
　　SQL> alter database convert to snapshot standby;
　　Database altered.
　　SQL> select database_role from v$database;
　　DATABASE_ROLE
----------------
SNAPSHOT STANDBY
　　
SQL> select open_mode from v$database;
　　OPEN_MODE
--------------------
MOUNTED
　　SQL> alter database open;
　　Database altered.
　　
数据库状态为read write，此时可以在数据库上做各种实验
　　SQL> select open_mode from v$database;
　　OPEN_MODE
--------------------
READ WRITE
　　SQL> select current_scn from v$database;
　　CURRENT_SCN
-----------
    6378976
　　SQL> /
　　CURRENT_SCN
-----------
    6378982
　　SQL> select primary_db_unique_name,db_unique_name,database_role from v$database;
　　PRIMARY_DB_UNIQUE_NAME         DB_UNIQUE_NAME                 DATABASE_ROLE
------------------------------ ------------------------------ ----------------
DREAM            DREAM01                              SNAPSHOT STANDBY
　　SQL>
　　数据库自己创建了1个还原点，用于还原
SQL> select name,storage_size from v$restore_point;
rows will be truncated
　　NAME
--------------------------------------------------------------------------------
SNAPSHOT_STANDBY_REQUIRED_06/19/2012 11:35:11
　　SQL>
　　代表SNAPSHOT_STANDBY_REQUIRED_06/19/2012 11:35:11这个还原点开启数据库闪回功能
　　SQL> select flashback_on from v$database;
　　FLASHBACK_ON
------------------
RESTORE POINT ONLY
　　下面我们再把数据库转换为physical standby
　　SQL> alter database convert to physical standby;
　　alter database convert to physical standby
*
ERROR at line 1:
ORA-01126: database must be mounted in this instance and not open in any instance
　　首先关闭快照数据库并重新启动到mount状态;
SQL> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.
　　SQL> startup mount;
ORACLE instance started.
　　Total System Global Area  534462464 bytes
Fixed Size       2228200 bytes
Variable Size      423624728 bytes
Database Buffers   100663296 bytes
Redo Buffers        7946240 bytes
Database mounted.
　　SQL> select flashback_on from v$database;
　　FLASHBACK_ON
------------------
RESTORE POINT ONLY
　　转换数据库到物理备库;
　　SQL> alter database convert to physical standby;
　　Database altered.
　　这时数据库是nomount状态;
　　SQL> select  primary_db_unique_name,db_unique_name,database_role from v$database;
select  primary_db_unique_name,db_unique_name,database_role from v$database
                                                                 *
ERROR at line 1:
ORA-01507: database not mounted
　　
SQL> select status from v$instance;
　　STATUS
------------
STARTED
　　我们手动启动到mount状态是不行的；
　　SQL> alter database mount;
alter database mount
*
ERROR at line 1:
ORA-00750: database has been previously mounted and dismounted
　　SQL> alter database open;
alter database open
*
ERROR at line 1:
ORA-01507: database not mounted
　　我们只能先关闭数据库，再从新打开;
　　SQL> shutdown immediate;
ORA-01507: database not mounted
　　ORACLE instance shut down.
　　SQL> startup mount;
　　ORACLE instance started.
　　Total System Global Area  534462464 bytes
Fixed Size       2228200 bytes
Variable Size      423624728 bytes
Database Buffers   100663296 bytes
Redo Buffers        7946240 bytes
Database mounted.
　　检查数据库角色
　　SQL>  select  primary_db_unique_name,db_unique_name,database_role from v$database;
　　PRIMARY_DB_UNIQUE_NAME         DB_UNIQUE_NAME                 DATABASE_ROLE
------------------------------ ------------------------------ ----------------
DREAM            DREAM01                              PHYSICAL STANDBY
　　转换成功，还原点已经被删除。
　　SQL> select name from v$restore_point;
　　NAME
--------------------------------------------------------------------------------------------------------------------------------
　　SQL> select flashback_on from v$database;
　　FLASHBACK_ON
------------------
NO
　　SQL> select open_mode from v$database;
　　OPEN_MODE
--------------------
MOUNTED
　　SQL> alter database open;
　　Database altered.
　　SQL>  select open_mode from v$database;
　　OPEN_MODE
--------------------
READ ONLY
　　SQL> alter database recover managed standby database using current logfile disconnect from session;
　　Database altered.
　　SQL> select open_mode,database_role from v$database;
　　OPEN_MODE      DATABASE_ROLE
-------------------- ----------------
READ ONLY WITH APPLY PHYSICAL STANDBY
　　SQL>
　　11.2.0.2G 功能很强大