1，使用rman备份集，创建一个物理备库

步骤=》http://space.itpub.net/23073818/viewspace-710475

2，备库停止接受日志

alter database recover managed standby database cancel;

3, 生成LogMiner 字典信息。

 主库执行：dg1:>execute dbms_logstdby.build

4，将物理备库转化成逻辑备库—备库要处于mount状态

SQL> show parameter db_name

 NAME                                 TYPE        VALUE

db_name                              string      dg1

SQL> alter  database recover to logical standby logdg2

4，修改逻辑备库的初始化参数

log_archive_dest_3='location=/home1/zz/arch_logdg2  valid_for=(standby_logfiles,standby_roles) db_unique_name=dg2'

log_archive_dest_1='location=/home1/zz/arch_dg2  valid_for=(online_logfiles,all_roles) db_unique_name=dg2'

5，创建备库的日志组

alter database add standby logfile group 4   '/home/oracle/oradata/dg2/standby01.dbf' size 20m;

alter database add standby logfile group 5   '/home/oracle/oradata/dg2/standby02.dbf' size 20m;

alter database add standby logfile group 6   '/home/oracle/oradata/dg2/standby03.dbf' size 20m;

alter database add standby logfile group 7   '/home/oracle/oradata/dg2/standby04.dbf' size 20m;

6，SQL> ALTER DATABASE OPEN  resetlogs;

应用日志

7，SQL> alter database start logical standby apply immediate;

此时逻辑备库创建完毕！