Oracle12c Windows 多实例ADG

Oracle12c Windows 多实例ADG

Oracle DG英文全称Oracle Data Guard，DG提供全面的服务包括：创建、维护、管理、以及监控standby数据库，确保数据安全。DG用途是构建企业数据高可用应用环境。ADG实际是实现自动切换主备的意思，这里关于A暂时不做配置。

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1. 环境介绍

1.1 安装环境

在主机1上安装数据库软件，并建监听和实例，在主机2上安装数据库软件，并建监听，可以不建实例。

项目	主机1（主库）	主机2（备库）
操作系统	Windows server 2016	Windows server 2016
主机名称	db31	db32
IP地址	172.16.103.31	172.16.103.32
Oracle版本	Oracle 12.2.0.1	Oracle 12.2.0.1
BASE	D:\app\Administrator\virtual	D:\app\Administrator\virtual
SID	orcl1,orcl2	orcl1,orcl2
db_unique_name	db31_orcl1，db31_orcl2	db32_orcl1，db32_orcl2

1.2 多实例启动问题

1.2.1 现象
先部署orcl1实例，在部署orcl2实例。部署后orcl2能正常shutdown/startup，而orcl1在shutdown之后startup不能正常启动，提示没有pfile配置文件。官方解决办法需要指定pfile(Oracle多实例启动)。但是如果只是为了启动实例，后面的ADG同样还是配置不下去的，后面还有很多报错依旧。

1.2.2 分析
在分析日志报错以及日志文件，最多的显示是“指定文件不存在、或无法识别、或无权限访问”。请牢记这个错误提示就是windows下文件权限导致的。
如当前的环境，orcl1不能直接启动需指定pfile，但明明指定路径下是有spfile文件，它为什么非要去读pfile文件呢？问题就在于我们orcl1的spfile的权限不正常。打开spfile的属性安全设置会发现，只有orcl2实例在权限，没有orcl1的权限。

1.2.3 解决办法
通过上面的分析，我们只有把属于orcl1实例的spfile文件的权限修改为everyone修改权限即可。当然其他属于orcl1实例的文件也需要修改。这里还需要把PWDorcl1.ORA文件权限修改正确。
如何修改window文件权限，这里不阐述。

1.3 如何切换实例

切换实例在linux下是修改环境配置文件。在window下直接使用实例名即可。如：

// 登入orc1
sqlplus sys/123456@orc1 as sysdba

// 登入orc2
sqlplus sys/123456@orc2 as sysdba

2. 监听配置

多实例也好，单实例也罢，监听文件只需要一份。在配置时需要注意区分开来。用做ADG的lis和tns，有多少个实例就配置多组，但文件只要一份。

2.1 listener.ora(主端)

# listener.ora Network Configuration File: D:\app\Administrator\virtual\product\12.2.0\dbhome_1\network\admin\listener.ora
# Generated by Oracle configuration tools.

SID_LIST_LISTENER =
  (SID_LIST =
    (SID_DESC =
      (SID_NAME = CLRExtProc)
      (ORACLE_HOME = D:\app\Administrator\virtual\product\12.2.0\dbhome_1)
      (PROGRAM = extproc)
      (ENVS = "EXTPROC_DLLS=ONLY:D:\app\Administrator\virtual\product\12.2.0\dbhome_1\bin\oraclr12.dll")
    )
    (SID_DESC =
      (GLOBAL_DBNAME = orcl1)
      (ORACLE_HOME = D:\app\Administrator\virtual\product\12.2.0\dbhome_1)
      (SID_NAME = orcl1)
      (ENVS = "EXTPROC_DLLS=ONLY:D:\app\Administrator\virtual\product\12.2.0\dbhome_1\bin\oraclr12.dll")
    )
    (SID_DESC =
      (GLOBAL_DBNAME = orcl2)
      (ORACLE_HOME = D:\app\Administrator\virtual\product\12.2.0\dbhome_1)
      (SID_NAME = orcl2)
      (ENVS = "EXTPROC_DLLS=ONLY:D:\app\Administrator\virtual\product\12.2.0\dbhome_1\bin\oraclr12.dll")
    )
  )

LISTENER =
  (DESCRIPTION_LIST =
    (DESCRIPTION =
      (ADDRESS = (PROTOCOL = TCP)(HOST = 172.16.103.31)(PORT = 1521))
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
    )
  )

2.2 listener.ora(备端)

# listener.ora Network Configuration File: D:\app\Administrator\virtual\product\12.2.0\dbhome_1\network\admin\listener.ora
# Generated by Oracle configuration tools.

SID_LIST_LISTENER =
  (SID_LIST =
    (SID_DESC =
      (SID_NAME = CLRExtProc)
      (ORACLE_HOME = D:\app\Administrator\virtual\product\12.2.0\dbhome_1)
      (PROGRAM = extproc)
      (ENVS = "EXTPROC_DLLS=ONLY:D:\app\Administrator\virtual\product\12.2.0\dbhome_1\bin\oraclr12.dll")
    )
    (SID_DESC =
      (GLOBAL_DBNAME = orcl1)
      (ORACLE_HOME = D:\app\Administrator\virtual\product\12.2.0\dbhome_1)
      (SID_NAME = orcl1)
      (ENVS = "EXTPROC_DLLS=ONLY:D:\app\Administrator\virtual\product\12.2.0\dbhome_1\bin\oraclr12.dll")
    )
    (SID_DESC =
      (GLOBAL_DBNAME = orcl2)
      (ORACLE_HOME = D:\app\Administrator\virtual\product\12.2.0\dbhome_1)
      (SID_NAME = orcl2)
      (ENVS = "EXTPROC_DLLS=ONLY:D:\app\Administrator\virtual\product\12.2.0\dbhome_1\bin\oraclr12.dll")
    )
  )

LISTENER =
  (DESCRIPTION_LIST =
    (DESCRIPTION =
      (ADDRESS = (PROTOCOL = TCP)(HOST = 172.16.103.32)(PORT = 1521))
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
    )
  )

2.3 tnsnames.ora(主端)

# tnsnames.ora Network Configuration File: D:\app\Administrator\virtual\product\12.2.0\dbhome_1\network\admin\tnsnames.ora
# Generated by Oracle configuration tools.

LISTENER_orcl1 =
  (ADDRESS = (PROTOCOL = TCP)(HOST = 172.16.103.31)(PORT = 1521))


LISTENER_orcl2 =
  (ADDRESS = (PROTOCOL = TCP)(HOST = 172.16.103.31)(PORT = 1521))


ORACLR_CONNECTION_DATA =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
    )
    (CONNECT_DATA =
      (SID = CLRExtProc)
      (PRESENTATION = RO)
    )
  )

orcl1 =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = 172.16.103.31)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = orcl1)
    )
  )

orcl2 =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = 172.16.103.31)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = orcl2)
    )
  )

orcl1_db31 =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = 172.16.103.31)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = orcl1)
    )
  )
orcl1_db32 =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = 172.16.103.32)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = orcl1)
    )
  )

orcl2_db31 =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = 172.16.103.31)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = orcl2)
    )
  )
orcl2_db32 =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = 172.16.103.32)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = orcl2)
    )
  )

2.4 tnsnames.ora(备端)

# tnsnames.ora Network Configuration File: D:\app\Administrator\virtual\product\12.2.0\dbhome_1\network\admin\tnsnames.ora
# Generated by Oracle configuration tools.

LISTENER_ORACLE12 =
  (ADDRESS = (PROTOCOL = TCP)(HOST = 172.16.103.32)(PORT = 1521))


LISTENER_ORCL =
  (ADDRESS = (PROTOCOL = TCP)(HOST = 172.16.103.32)(PORT = 1521))


ORACLR_CONNECTION_DATA =
  (DESCRIPTION =
    (ADDRESS_LIST =
      (ADDRESS = (PROTOCOL = IPC)(KEY = EXTPROC1521))
    )
    (CONNECT_DATA =
      (SID = CLRExtProc)
      (PRESENTATION = RO)
    )
  )

ORCL1 =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = 172.16.103.32)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = orcl1)
    )
  )

ORCL2 =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = 172.16.103.32)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = orcl2)
    )
  )
orcl1_db31 =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = 172.16.103.31)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = orcl1)
    )
  )
orcl1_db32 =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = 172.16.103.32)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = orcl1)
    )
  )

orcl2_db31 =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = 172.16.103.31)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = orcl2)
    )
  )
orcl2_db32 =
  (DESCRIPTION =
    (ADDRESS = (PROTOCOL = TCP)(HOST = 172.16.103.32)(PORT = 1521))
    (CONNECT_DATA =
      (SERVER = DEDICATED)
      (SERVICE_NAME = orcl2)
    )
  )

2.5 重启监听

lsnrctl stop
lsnrctl start

3. 实例orcl1

3.1 归档/闪回/强档

# 登录(主端)
sqlplus sys/123456@orcl1 as sysdba
SQL> select instance_name,status from v$instance;
SQL> show pdbs  //确定容器数据库

# 查看归档/闪回/强档(主端)
SQL> archive log list;
SQL> select flashback_on from v$database;
SQL> select force_logging from v$database;
SQL> show parameter db_recovery_file_dest;

# 开启强档/归档/闪回(主端)
SQL> alter database force logging;

SQL> alter system set db_recovery_file_dest='D:\app\Administrator\virtual\fast_recovery_area';
SQL> alter system set db_recovery_file_dest_size='40G';
// 此设置会变为临时设置
// 正确的做法是收到添加pfile文件里
// *.db_recovery_file_dest='D:\app\Administrator\virtual\fast_recovery_area'
// *.db_recovery_file_dest_size=42949672960

SQL> shutdown immediate;
SQL> startup pfile=D:\app\Administrator\virtual\product\12.2.0\dbhome_1\database\initorcl1.ora mount;

SQL> alter database archivelog;
SQL> alter database flashback on;

SQL> alter database open;
SQL> alter pluggable database all open; //开启容器数据库

3.2 standby日志

SQL> SELECT GROUP#,ARCHIVED,STATUS,BYTES/1024/1024 FROM V$LOG;
SQL> SELECT GROUP#,MEMBER FROM V$LOGFILE;

SQL> 
ALTER DATABASE ADD STANDBY LOGFILE GROUP 11 'D:\APP\ADMINISTRATOR\VIRTUAL\ORADATA\ORCL1\redo11_stb01_log' size 200M;

ALTER DATABASE ADD STANDBY LOGFILE GROUP 12 'D:\APP\ADMINISTRATOR\VIRTUAL\ORADATA\ORCL1\redo12_stb02_log' size 200M;

ALTER DATABASE ADD STANDBY LOGFILE GROUP 13 'D:\APP\ADMINISTRATOR\VIRTUAL\ORADATA\ORCL1\redo13_stb03_log' size 200M;

ALTER DATABASE ADD STANDBY LOGFILE GROUP 14 'D:\APP\ADMINISTRATOR\VIRTUAL\ORADATA\ORCL1\redo14_stb04_log' size 200M;

3.3 pfile文件/pwd密码

# pfile调试
SQL> set line 1000;
SQL> select instance_name,status from v$instance;
SQL> show parameter spfile;
SQL> show parameter name;
SQL> select open_mode from v$database;
SQL> select decode(count(*),1,'spfile','pfile') from v$spparameter where rownum=1 and isspecified ='TRUE';

# 创建pfile
// 如1.2所说，多实例启动指定pfile文件。这里只需修改pfile文件
## 主站配置(在末尾添加)
*.db_unique_name='orcl1_db31'
*.fal_server='orcl1_db32'
*.log_archive_config='dg_config=(orcl1_db31,orcl1_db32)'
*.log_archive_dest_1='location=use_db_recovery_file_dest valid_for=(all_logfiles, all_roles) db_unique_name=orcl1_db31'
*.log_archive_dest_2='service=orcl1_db32 lgwr async valid_for=(online_logfile,primary_role) db_unique_name=orcl1_db32'
*.log_archive_dest_state_1=ENABLE
*.log_archive_dest_state_2=ENABLE
*.standby_file_management='AUTO'
*.db_file_name_convert='D:\app\Administrator\virtual\oradata\ORCL1','D:\app\Administrator\virtual\oradata\ORCL1'
*.log_file_name_convert='D:\app\Administrator\virtual\oradata\ORCL1','D:\app\Administrator\virtual\oradata\ORCL1'

## 备站配置(在末尾添加)
*.db_unique_name='orcl1_db32'
*.fal_server='orcl1_db31'
*.log_archive_config='dg_config=(orcl1_db31,orcl1_db32)'
*.log_archive_dest_1='location=use_db_recovery_file_dest valid_for=(all_logfiles, all_roles) db_unique_name=orcl1_db32'
*.log_archive_dest_2='service=orcl1_db31 lgwr async valid_for=(online_logfile,primary_role) db_unique_name=orcl1_db31'
*.log_archive_dest_state_1=ENABLE
*.log_archive_dest_state_2=ENABLE
*.standby_file_management='AUTO'
*.db_file_name_convert='D:\app\Administrator\virtual\oradata\ORCL1','D:\app\Administrator\virtual\oradata\ORCL1'
*.log_file_name_convert='D:\app\Administrator\virtual\oradata\ORCL1','D:\app\Administrator\virtual\oradata\ORCL1'

# 生成spfile(主端)
SQL> shutdown immediate;
SQL> create spfile from pfile;
SQL> startup;
SQL> alter pluggable database all open;

# 生成spfile(备端)
SQL> shutdown immediate;
SQL> create spfile from pfile;
SQL> startup nomount;

# 将密码文件拷贝到备端(注意文件权限)
D:\app\Administrator\virtual\product\12.2.0\dbhome_1\database\PWDorcl.ORA

3.4 RMAN复制开启同步

# cmd下执行RMAN复制（备端）
rman target sys/123456@orcl1_db31 auxiliary sys/123456@orcl1_db32

# RMAN下执行复制
RMAN> duplicate target database for standby from active database nofilenamecheck;

# SQL下开启同步
SQL> alter database recover managed standby database using current logfile disconnect from session;

## 取消同步
SQL> alter database recover managed standby database cancel; 

# 备端打开数据库
SQL> select status from v$instance;
SQL> alter database open;
SQL> alter pluggable database all open;

# 备库开闪回
SQL> select flashback_on from v$database;
alter database flashback on;

# SQL下开启同步
SQL> alter database recover managed standby database using current logfile disconnect from session;

3.5 DG验证

# 主备库状态
SQL> select switchover_status,database_role from v$database;

# 主备库归档序号
SQL> 
select thread#, max(sequence#) "Last Standby Seq Applied"
from v$archived_log val, v$database vdb
where val.resetlogs_change# = vdb.resetlogs_change#
and val.applied in ('YES','IN-MEMORY')
group by thread# order by 1;

# 备库DG进程
SQL> select process,client_process,sequence#,status from v$managed_standby;

# 备库模式
SQL> select database_role,protection_mode,protection_level,open_mode from v$database;

# 主库创建表
create table test as select * from dba_objects where rownum < 101;
# 备库查询
select count(*) from test;    ## 结果为100表示实时同步成功
# 主库删除
drop table test purge;

4. 实例orcl2

3.1 归档/闪回/强档

# 登录(主端)
sqlplus sys/123456@orcl2 as sysdba
SQL> select instance_name,status from v$instance;
SQL> show pdbs

# 查看归档/闪回/强档(主端)
SQL> archive log list;
SQL> select flashback_on from v$database;
SQL> select force_logging from v$database;
SQL> show parameter db_recovery_file_dest;

# 开启强档/归档/闪回(主端)
SQL> alter database force logging;
SQL> alter system set db_recovery_file_dest='D:\app\Administrator\virtual\fast_recovery_area';
SQL> alter system set db_recovery_file_dest_size='40G';

SQL> shutdown immediate;
SQL> startup mount;

SQL> alter database archivelog;
SQL> alter database flashback on;

SQL> alter database open;
SQL> alter pluggable database all open;

3.2 standby

SQL> SELECT GROUP#,ARCHIVED,STATUS,BYTES/1024/1024 FROM V$LOG;
SQL> SELECT GROUP#,MEMBER FROM V$LOGFILE;

SQL> 
ALTER DATABASE ADD STANDBY LOGFILE GROUP 11 'D:\APP\ADMINISTRATOR\VIRTUAL\ORADATA\ORCL2\redo11_stb01_log' size 200M;

ALTER DATABASE ADD STANDBY LOGFILE GROUP 12 'D:\APP\ADMINISTRATOR\VIRTUAL\ORADATA\ORCL2\redo12_stb02_log' size 200M;

ALTER DATABASE ADD STANDBY LOGFILE GROUP 13 'D:\APP\ADMINISTRATOR\VIRTUAL\ORADATA\ORCL2\redo13_stb03_log' size 200M;

ALTER DATABASE ADD STANDBY LOGFILE GROUP 14 'D:\APP\ADMINISTRATOR\VIRTUAL\ORADATA\ORCL2\redo14_stb04_log' size 200M;

3.3 pfile/spfile/密码

# pfile调试
SQL> set line 1000;
SQL> select instance_name,status from v$instance;
SQL> show parameter spfile;
SQL> show parameter name;
SQL> select open_mode from v$database;
SQL> select decode(count(*),1,'spfile','pfile') from v$spparameter where rownum=1 and isspecified ='TRUE';
SQL> startup pfile='D:\app\Administrator\virtual\product\12.2.0\dbhome_1\database\INITORACLE12.ORA'
SQL> SELECT NAME, VALUE, DISPLAY_VALUE FROM V$PARAMETER WHERE NAME ='spfile';

# 创建pfile
SQL> create pfile from spfile;

# 将pfile文件和密码文件拷贝到备端
D:\app\Administrator\virtual\product\12.2.0\dbhome_1\database\INITORCL.ORA
D:\app\Administrator\virtual\product\12.2.0\dbhome_1\database\PWDorcl.ORA

# 修改pfile文件，在INITORCL.ora末尾追加下面内容
## 主站配置
*.db_unique_name='orcl2_db31'
*.fal_server='orcl2_db32'
*.log_archive_config='dg_config=(orcl2_db31,orcl2_db32)'
*.log_archive_dest_1='location=use_db_recovery_file_dest valid_for=(all_logfiles, all_roles) db_unique_name=orcl2_db31'
*.log_archive_dest_2='service=orcl2_db32 lgwr async valid_for=(online_logfile,primary_role) db_unique_name=orcl2_db32'
*.log_archive_dest_state_1=ENABLE
*.log_archive_dest_state_2=ENABLE
*.standby_file_management='AUTO'
*.db_file_name_convert='D:\app\Administrator\virtual\oradata\orcl2','D:\app\Administrator\virtual\oradata\orcl2'
*.log_file_name_convert='D:\app\Administrator\virtual\oradata\orcl2','D:\app\Administrator\virtual\oradata\orcl2'

## 备站配置
*.db_unique_name='orcl2_db32'
*.fal_server='orcl2_db31'
*.log_archive_config='dg_config=(orcl2_db31,orcl2_db32)'
*.log_archive_dest_1='location=use_db_recovery_file_dest valid_for=(all_logfiles, all_roles) db_unique_name=orcl2_db32'
*.log_archive_dest_2='service=orcl2_db31 lgwr async valid_for=(online_logfile,primary_role) db_unique_name=orcl2_db31'
*.log_archive_dest_state_1=ENABLE
*.log_archive_dest_state_2=ENABLE
*.standby_file_management='AUTO'
*.db_file_name_convert='D:\app\Administrator\virtual\oradata\orcl2','D:\app\Administrator\virtual\oradata\orcl2'
*.log_file_name_convert='D:\app\Administrator\virtual\oradata\orcl2','D:\app\Administrator\virtual\oradata\orcl2'

# 生成spfile(主端)
SQL> shutdown immediate;
SQL> create spfile from pfile;
SQL> startup;
SQL> alter pluggable database all open;

# 生成spfile(备端)
SQL> shutdown immediate;
SQL> create spfile from pfile;
SQL> startup nomount;

# 将密码文件拷贝到备端(注意文件权限)
D:\app\Administrator\virtual\product\12.2.0\dbhome_1\database\PWDorc2.ORA

3.4 RMAN复制开启同步

# cmd下执行RMAN复制（备端）
rman target sys/123456@orcl2_db31 auxiliary sys/123456@orcl2_db32

# RMAN下执行复制
RMAN> duplicate target database for standby from active database nofilenamecheck;

# SQL下开启同步
SQL> alter database recover managed standby database using current logfile disconnect from session;

## 取消同步
SQL> alter database recover managed standby database cancel; 

# 备端打开数据库
SQL> select status from v$instance;
SQL> alter database open;
SQL> alter pluggable database all open;

# 备库开闪回
SQL> select flashback_on from v$database;
alter database flashback on;

# SQL下开启同步
SQL> alter database recover managed standby database using current logfile disconnect from session;

3.5 DG验证

# 主备库状态
SQL> select switchover_status,database_role from v$database;

# 主备库归档序号
SQL> 
select thread#, max(sequence#) "Last Standby Seq Applied"
from v$archived_log val, v$database vdb
where val.resetlogs_change# = vdb.resetlogs_change#
and val.applied in ('YES','IN-MEMORY')
group by thread# order by 1;

# 归档应用
SQL> SELECT SEQUENCE#, FIRST_TIME, NEXT_TIME,APPLIED,DELETED FROM V$ARCHIVED_LOG WHERE DELETED='NO' ORDER BY SEQUENCE#;

# 备库DG进程
SQL> select process,client_process,sequence#,status from v$managed_standby;

# 备库模式
SQL> select database_role,protection_mode,protection_level,open_mode from v$database;

# 主库创建表
create table test as select * from dba_objects where rownum < 101;
# 备库查询
select count(*) from test;    ## 结果为100表示实时同步成功
# 主库删除
drop table test purge;

5 手动断开DG

# 关闭同步
SQL> alter database recover managed standby database cancel; 

# 强制停止redo apply
SQL> alter database recover managed standby database finish force;

# 查看备库状态
SQL> select switchover_status,database_role from v$database;
SWITCHOVER_STATUS            DATABASE_ROLE
---------------------------------------- --------------------------------
SESSIONS ACTIVE              PHYSICAL STANDBY

# 切换为primary
SQL> alter database commit to switchover to primary with session shutdown; 

# 打开数据库
SQL> alter database open;

# 验证数据库模式
SQL> select database_role,protection_mode,protection_level,open_mode from v$database;
DATABASE_ROLE       PROTECTION_MODE       PROTECTION_LEVEL      OPEN_MODE
-----------------  --------------------- --------------------- ---------------
PHYSICAL STANDBY    MAXIMUM PERFORMANCE   MAXIMUM PERFORMANCE   READ WRITE