這個需求比較特別，由於使用者空間及儲存效能的問題，希望將物理備庫直接轉變稱主庫，原備庫退出DG環境。

Oracle提供了相對較為簡單的方法，供參考：

1. Confirm Primary Database in Maximum Performance Mode

2. Remove Data Guard Broker Configuration
DGMGRL> REMOVE CONFIGURATION;
 
3. Unset Data Guard-specific Initialization Parameters //此處前提安裝了配置了DG Broker
Unset/Remove following Initialization Parameters from the (S)PFILE of the Primary Database:

LOG_ARCHIVE_CONFIG
DB_FILE_NAME_CONVERT
LOG_FILE_NAME_CONVERT
LOG_ARCHIVE_DEST_n pointing to the Standby Database and valid for STANDBY_LOGFILES
LOG_ARCHIVE_DEST_STATE_n
DG_BROKER_START
DG_BROKER_CONFIG_FILE1
DG_BROKER_CONFIG_FILE2
STANDBY_ARCHIVE_DEST
STANDBY_FILE_MANAGEMENT
FAL_SERVER
FAL_CLIENT

4. Drop Standby Redologs from the Primary Database

Use following Query to check for Standby Redolog Groups:
SQL> SELECT GROUP# FROM V$STANDBY_LOG;

5. Drop the Data Guard Broker Configuration Files if used.

DG_BROKER_CONFIG_FILE1 and DG_BROKER_CONFIG_FILE2 Parameters define the Name and Location of the Data Guard Broker Configuration Files.
SQL> show parameter DG_BROKER_CONFIG;

drop following file
/ora/u05/recovery_area/dr1cpoln01.dat
/ora/u05/recovery_area/dr2cpoln01.dat

6. covert standby to standalone database

$  sqlplus / as sysdba
SQL>  ALTER DATABASE ACTIVATE PHYSICAL STANDBY DATABASE;
SQL>  SHUTDOWN IMMEDIATE;
SQL>  STARTUP

7.Modify standby database‘ database id

SQL>select dbid,name from v$database;

SQL>  SHUTDOWN IMMEDIATE;
SQL>  STARTUP MOUNT;

nid target=/ dbname=NEWDB

SQL>  alter system set db_name='CPOLN02' scope=spfile;

SQL>  SHUTDOWN IMMEDIATE;
SQL>  STARTUP MOUNT;
SQL>  alter database open resetlogs;