背景：某客户Oracle 10g 的DG由于空间不足，之前将部分数据文件迁移到其他目录，如今原目录扩容成功，要将之前迁移的数据文件再次迁移回来。
环境：Oracle 10.2.0.5 DG 单机

首先想到的是10gDG是在mount模式下应用的，在测试环境可以很容易的模拟下这个需求实现的过程：

• 1.查询当前DG的状态
• 2.停止DG应用
• 3.备份copy副本到新目录并切换
• 4.删除之前的目录并开启应用

1.查询当前DG的状态

查询当前DG的状态:

Connected to:
Oracle Database 10g Enterprise Edition Release 10.2.0.5.0 - 64bit Production
With the Partitioning, OLAP, Data Mining and Real Application Testing optionsSQL> select name, database_role, open_mode from gv$database;NAME      DATABASE_ROLE    OPEN_MODE
--------- ---------------- ----------
JY        PHYSICAL STANDBY MOUNTEDSQL>  select recovery_mode from v$archive_dest_status;RECOVERY_MODE
-----------------------
MANAGED REAL TIME APPLY
IDLE
IDLE
IDLE
IDLE
IDLE
IDLE
IDLE
IDLE
IDLE
IDLE11 rows selected.SQL> select * from v$dataguard_stats;NAME                               VALUE                                                            UNIT                           TIME_COMPUTED
---------------------------------- ---------------------------------------------------------------- ------------------------------ ------------------------------
apply finish time                  +00 00:00:00.0                                                   day(2) to second(1) interval   05-MAY-2018 10:04:20
apply lag                          +00 00:00:12                                                     day(2) to second(0) interval   05-MAY-2018 10:04:20
estimated startup time             41                                                               second                         05-MAY-2018 10:04:20
standby has been open              N                                                                                               05-MAY-2018 10:04:20
transport lag                      +00 00:00:00                                                     day(2) to second(0) interval   05-MAY-2018 10:04:20

可以看到DG处于正常应用状态。

2.停止DG应用

停止DG应用：

SQL> alter database recover managed standby database cancel;Database altered.

3.备份copy副本到新目录并切换

3.1 确认需要迁移的数据文件
查看当前的数据文件，确认将9,10,11三个文件迁移回原来的目录：

SQL> select file#, name from v$datafile;FILE# NAME
---------- -------------------------------------------------------1 /oradata/jy/datafile/system.256.8396738752 /oradata/jy/datafile/undotbs1.258.8396738773 /oradata/jy/datafile/sysaux.257.8396738774 /oradata/jy/datafile/users.259.8396738775 /oradata/jy/datafile/example.267.8396739616 /oradata/jy/datafile/undotbs2.268.8396741037 /oradata/jy/datafile/dbs_d_school.276.8406184378 /oradata/jy/datafile/dbs_cssf_gt.289.8482287419 /datafile/dbs_data9.dbf10 /datafile/dbs_data10.dbf11 /datafile/dbs_data11.dbf11 rows selected.

3.2 备份相关数据文件副本：
编写脚本：
vi copy_datafile.sh

echo "=======Begin at : `date`=======" >>/tmp/copy_datafile_`date +%Y%m%d`.log
rman target / <<EOF >>/tmp/copy_datafile_`date +%Y%m%d`.log
run {
allocate channel c1 device type disk;
allocate channel c2 device type disk;
allocate channel c3 device type disk;backup as copy datafile 9 format '/oradata/jy/datafile/dbs_data9.dbf';
backup as copy datafile 10 format '/oradata/jy/datafile/dbs_data10.dbf';
backup as copy datafile 11 format '/oradata/jy/datafile/dbs_data11.dbf';release channel c1;
release channel c2;
release channel c3;
}
EOF
echo "=======End at : `date`=======" >>/tmp/copy_datafile_`date +%Y%m%d`.log

后台执行脚本：

nohup sh copy_datafile.sh &

记录的日志如下：

=======Begin at : Sat May  5 10:51:24 CST 2018=======Recovery Manager: Release 10.2.0.5.0 - Production on Sat May 5 10:51:24 2018Copyright (c) 1982, 2007, Oracle.  All rights reserved.connected to target database: JY (DBID=857123342, not open)RMAN> 2> 3> 4> 5> 6> 7> 8> 9> 10> 11> 12> 13>
using target database control file instead of recovery catalog
allocated channel: c1
channel c1: sid=152 devtype=DISKallocated channel: c2
channel c2: sid=159 devtype=DISKallocated channel: c3
channel c3: sid=144 devtype=DISKStarting backup at 05-MAY-18
channel c1: starting datafile copy
input datafile fno=00009 name=/datafile/dbs_data9.dbf
output filename=/oradata/jy/datafile/dbs_data9.dbf tag=TAG20180505T105125 recid=22 stamp=975322288
channel c1: datafile copy complete, elapsed time: 00:00:03
Finished backup at 05-MAY-18Starting backup at 05-MAY-18
channel c1: starting datafile copy
input datafile fno=00010 name=/datafile/dbs_data10.dbf
output filename=/oradata/jy/datafile/dbs_data10.dbf tag=TAG20180505T105129 recid=23 stamp=975322292
channel c1: datafile copy complete, elapsed time: 00:00:07
Finished backup at 05-MAY-18Starting backup at 05-MAY-18
channel c1: starting datafile copy
input datafile fno=00011 name=/datafile/dbs_data11.dbf
output filename=/oradata/jy/datafile/dbs_data11.dbf tag=TAG20180505T105136 recid=24 stamp=975322315
channel c1: datafile copy complete, elapsed time: 00:00:25
Finished backup at 05-MAY-18released channel: c1released channel: c2released channel: c3RMAN> Recovery Manager complete.
=======End at : Sat May  5 10:52:02 CST 2018=======

3.3 切换数据文件到copy副本：

RMAN> list copy of database;using target database control file instead of recovery catalogList of Datafile Copies
Key     File S Completion Time Ckp SCN    Ckp Time        Name
------- ---- - --------------- ---------- --------------- ----
10      9    A 05-MAY-18       35303533   05-MAY-18       /oradata/jy/datafile/dbs_data9.dbf
11      10   A 05-MAY-18       35303533   05-MAY-18       /oradata/jy/datafile/dbs_data10.dbf
12      11   A 05-MAY-18       35303533   05-MAY-18       /oradata/jy/datafile/dbs_data11.dbfRMAN> switch datafile 9,10,11 to copy;datafile 9 switched to datafile copy "/oradata/jy/datafile/dbs_data9.dbf"
datafile 10 switched to datafile copy "/oradata/jy/datafile/dbs_data10.dbf"
datafile 11 switched to datafile copy "/oradata/jy/datafile/dbs_data11.dbf"

4.删除之前的目录并开启应用

4.1 删除之前的文件：

RMAN> list copy of database;List of Datafile Copies
Key     File S Completion Time Ckp SCN    Ckp Time        Name
------- ---- - --------------- ---------- --------------- ----
13      9    A 05-MAY-18       35309314   05-MAY-18       /datafile/data9.dbf
14      10   A 05-MAY-18       35309314   05-MAY-18       /datafile/data10.dbf
15      11   A 05-MAY-18       35309314   05-MAY-18       /datafile/datafile11.dbfRMAN> delete copy of datafile 9,10,11;allocated channel: ORA_DISK_1
channel ORA_DISK_1: sid=146 devtype=DISKList of Datafile Copies
Key     File S Completion Time Ckp SCN    Ckp Time        Name
------- ---- - --------------- ---------- --------------- ----
13      9    A 05-MAY-18       35309314   05-MAY-18       /datafile/data9.dbf
14      10   A 05-MAY-18       35309314   05-MAY-18       /datafile/data10.dbf
15      11   A 05-MAY-18       35309314   05-MAY-18       /datafile/datafile11.dbfDo you really want to delete the above objects (enter YES or NO)? yes
deleted datafile copy
datafile copy filename=/datafile/data9.dbf recid=13 stamp=975320371
deleted datafile copy
datafile copy filename=/datafile/data10.dbf recid=14 stamp=975320371
deleted datafile copy
datafile copy filename=/datafile/datafile11.dbf recid=15 stamp=975320371
Deleted 3 objects

4.2 开启日志应用：

SQL> --recover_std_real
SQL> alter database recover managed standby database using current logfile disconnect from session;Database altered.SQL> set lines 1000
SQL> select * from v$dataguard_stats;NAME                             VALUE                                                            UNIT                           TIME_COMPUTED
-------------------------------- ---------------------------------------------------------------- ------------------------------ ------------------------------
apply finish time                +00 00:00:00.0                                                   day(2) to second(1) interval   05-MAY-2018 10:20:56
apply lag                        +00 00:02:00                                                     day(2) to second(0) interval   05-MAY-2018 10:20:56
estimated startup time           41                                                               second                         05-MAY-2018 10:20:56
standby has been open            N                                                                                               05-MAY-2018 10:20:56
transport lag                    +00 00:00:00                                                     day(2) to second(0) interval   05-MAY-2018 10:20:56SQL>  select recovery_mode from v$archive_dest_status;RECOVERY_MODE
-----------------------
MANAGED REAL TIME APPLY
IDLE
IDLE
IDLE
IDLE
IDLE
IDLE
IDLE
IDLE
IDLE
IDLE11 rows selected.

至此，就完成了客户的需求，我们可以多思考一下，如果客户环境是11g的ADG环境呢？会有哪些不同呢？