可以参考如下步骤：

12C新特性修复

首先，模拟备库断电，主库切几个最新的归档，然后手工删掉，重新开启DG同步。

模拟GAP期间，有数据文件添加的情况：

##主库添加数据文件
alter tablespace TEST add datafile '/oradata/ORCL/test02.dbf' size 100M autoextend off;
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📢 注意： 当前DG数据库已存在GAP，GAP日志为：30—31 。

a.记录备库当前SCN号

备库记录当前 scn 号：

sqlplus / as sysdba
SELECT CURRENT_SCN FROM V$DATABASE;
CURRENT_SCN
-----------
2600487
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b.使用recover standby using service恢复

采用rman的新功能，recover standby using service，通过RMAN连接到target备库，然后用主库的service执行恢复备库命令。

语法：

RECOVER DATABASE FROM SERVICE < PRIMARY DB SERVICE NAME > NOREDO USING COMPRESSED BACKUPSET;

📢 注意： 确认主库的TNS已配置，这里的< PRIMARY DB SERVICE NAME >即 TNSNAME。

c.备库启动到nomount状态，恢复控制文件

备库启动到nomount状态：

sqlplus / as sysdba
shutdown immediate
startup nomount
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备库通过from service恢复控制文件：

rman target /
restore standby controlfile from service orcl;
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备库开启到mount状态：

sqlplus / as sysdba
alter database mount;
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d.备库恢复，修复GAP

检查主备GAP期间是否添加数据文件：

sqlplus / as sysdba
select file# from v$datafile where creation_change# > =2600487;

FILE#
----------
13
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restore 新添加的数据文件：

rman target /
run
{
SET NEWNAME FOR DATABASE TO '/oradata/ORCL_STBY/%f_%U';
RESTORE DATAFILE 13 FROM SERVICE orcl;
}
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由于主备的数据文件目录不一致，需要修改controlfile中数据文件位置：

rman target /
catalog start with '/oradata/ORCL_STBY';
YES
SWITCH DATABASE TO COPY;
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将备库文件管理方式改为手动：

sqlplus / as sysdba
alter system set standby_file_management=MANUAL;
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重命名 tempfile && logfile：

sqlplus / as sysdba
##logfile
alter database clear logfile group 1;
alter database clear logfile group 2;
alter database clear logfile group 3;
alter database clear logfile group 4;
alter database clear logfile group 5;
alter database clear logfile group 6;
alter database clear logfile group 7;
alter database rename file '/oradata/ORCL/redo03.log' to '/oradata/ORCL_STBY/redo03.log';
alter database rename file '/oradata/ORCL/redo02.log' to '/oradata/ORCL_STBY/redo02.log';
alter database rename file '/oradata/ORCL/redo01.log' to '/oradata/ORCL_STBY/redo01.log';
alter database rename file '/oradata/ORCL/standby_redo04.log' to '/oradata/ORCL_STBY/standby_redo04.log';
alter database rename file '/oradata/ORCL/standby_redo05.log' to '/oradata/ORCL_STBY/standby_redo05.log';
alter database rename file '/oradata/ORCL/standby_redo06.log' to '/oradata/ORCL_STBY/standby_redo06.log';
alter database rename file '/oradata/ORCL/standby_redo07.log' to '/oradata/ORCL_STBY/standby_redo07.log';
##tempfile
alter database rename file '/oradata/ORCL/temp01.dbf' to '/oradata/ORCL_STBY/temp01.dbf';
alter database rename file '/oradata/ORCL/pdbseed/temp012021-04-11_06-13-50-844-AM.dbf' to '/oradata/ORCL_STBY/pdbseed/temp012021-04-11_06-13-50-844-AM.dbf';
alter database rename file '/oradata/ORCL/BFA6BEE45A1E3605E053AC01A8C0DD20/datafile/o1_mf_temp_j749f5fy_.dbf' to '/oradata/ORCL_STBY/BFA6BEE45A1E3605E053AC01A8C0DD20/datafile/o1_mf_temp_j749f5fy_.dbf';
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备库重命名完后再改为自动：

sqlplus / as sysdba
alter system set standby_file_management=AUTO;
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恢复主备GAP：

recover database from service orcl noredo using compressed backupset;
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📢 注意： 如果主备库文件目录不一致，则需要catalog切换控制文件中路径，否则报错：

e.开启备库日志应用，检查同步

• 检查主备scn是否一致

sqlplus / as sysdba
col HXFNM for a100
set line222
select HXFIL File_num,substr(HXFNM,1,40) HXFNM,fhscn from x$kcvfh;
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• 主库切几次归档

sqlplus / as sysdba
ALTER SYSTEM ARCHIVE LOG CURRENT;
ALTER SYSTEM SWITCH LOGFILE;
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• 开启备库应用日志

sqlplus / as sysdba
alter database open;
alter pluggable database all open;
ALTER DATABASE RECOVER MANAGED STANDBY DATABASE USING CURRENT LOGFILE DISCONNECT FROM SESSION;
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• 查看备库同步是否正常

sqlplus / as sysdba
set line222
col member for a60
select t1.group#,t1.thread#,t1.bytes/1024/1024,t1.status,t2.member from gv$standby_log t1,gv$logfile t2 where t1.group#=t2.group#;
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• 主库插入数据

sqlplus test/test@pdb01
insert into test values (999);
commit;
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• 备库查询是否实时同步

alter session set container=pdb01;
select * from test.test;
ID
----------
1
2
999
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至此，GAP已修复完成，可以发现，12C这个新特性，将一些步骤进行了省略和封装，进一步减少了我们的操作步骤，但是内部的原理仍然是一致的。

前面步骤都一样，到这边catalog不知道怎么报错了

控制文件恢复了呀

[oracle@hisdg ~]$ rman target /

Recovery Manager: Release 12.2.0.1.0 - Production on Mon Jan 10 18:06:37 2022

Copyright (c) 1982, 2017, Oracle and/or its affiliates. All rights reserved.

connected to target database: CRDS3DB (not mounted)

RMAN> restore standby controlfile from service crds3db;

Starting restore at 2022-01-10 18:06:49
using target database control file instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=35 device type=DISK

channel ORA_DISK_1: starting datafile backup set restore
channel ORA_DISK_1: using network backup set from service crds3db
channel ORA_DISK_1: restoring control file
channel ORA_DISK_1: restore complete, elapsed time: 00:00:01
output file name=/app/oracle/oradata/crds3dbdg/control01.ctl
output file name=/app/oracle/oradata/crds3dbdg/control02.ctl
Finished restore at 2022-01-10 18:06:50