我们上一讲讲到了RMAN能提供全库备份、表空间备份、数据文件备份、归档日志备份、控制文件及参数文件的备份。RMAN备份出来的文件称之为备份集，RMAN在备份的过程中，只备份已经使用过的数据块。RMAN将多个数据文件打包到一起，生成一个备份集。数据文件与备份集文件不再是一一对应的关系。关于备份集的概念，我们下一讲再详细介绍。本将我们说说RMAN的另一种备份方式--镜像copy。
成都做网站、网站制作介绍好的网站是理念、设计和技术的结合。
创新互联拥有的网站设计理念、多方位的设计风格、经验丰富的设计团队。提供PC端+手机端网站建设，用营销思维进行网站设计、采用先进技术开源代码、注重用户体验与SEO基础，将技术与创意整合到网站之中，以契合客户的方式做到创意性的视觉化效果。
镜像copy是单个数据文件、控制文件、归档日志的克隆。备份出来的备份文件与数据库文件一一对应。下图描述了备份集与镜像copy之间的区别
镜像copy可以使用RMAN的backup as copy命令生成，也可以使用操作系统命令生成。
使用backup as copy命令备份时，Oracle服务器会话验证数据文件中的数据块，并且会将此次备份操作记录到控制文件中。我们知道，如果使用操作系统命令进行热备，首先要在数据库中执行begin backup命令，执行该命令后，数据文件的头部将被冷冻，在备份期间，为了保证数据块的有效性，一旦数据块被修改，那么日志文件将记录下该数据块的原始镜像。如果使用RMAN的backup as copy命令进行备份，则无需执行begin backup。 因为rman在备份的过程中会检查数据块的一致性，直到数据块一致了，才将其copy到备份文件中。
镜像copy有如下特征：
执行镜像copy
RMAN> backup as copy database;
Starting backup at 2015/07/08 11:53:55
using target database control file instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=39 device type=DISK
channel ORA_DISK_1: starting datafile copy
input datafile file number=00001 name=/u01/app/oracle/oradata/devdb/system01.dbf
output file name=/u01/app/oracle/fast_recovery_area/DEVDB/datafile/o1_mf_system_bss7pnh3_.dbf tag=TAG20150708T115355 RECID=9 STAMP=884519670
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:35
channel ORA_DISK_1: starting datafile copy
input datafile file number=00002 name=/u01/app/oracle/oradata/devdb/sysaux01.dbf
output file name=/u01/app/oracle/fast_recovery_area/DEVDB/datafile/o1_mf_sysaux_bss7qqqg_.dbf tag=TAG20150708T115355 RECID=10 STAMP=884519692
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:25
channel ORA_DISK_1: starting datafile copy
input datafile file number=00005 name=/u01/app/oracle/oradata/devdb/example01.dbf
output file name=/u01/app/oracle/fast_recovery_area/DEVDB/datafile/o1_mf_example_bss7rk3f_.dbf tag=TAG20150708T115355 RECID=11 STAMP=884519708
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:15
channel ORA_DISK_1: starting datafile copy
input datafile file number=00003 name=/u01/app/oracle/oradata/devdb/undotbs01.dbf
output file name=/u01/app/oracle/fast_recovery_area/DEVDB/datafile/o1_mf_undotbs1_bss7s07q_.dbf tag=TAG20150708T115355 RECID=12 STAMP=884519715
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:07
channel ORA_DISK_1: starting datafile copy
input datafile file number=00006 name=/u01/app/oracle/oradata/devdb/idx01.dbf
output file name=/u01/app/oracle/fast_recovery_area/DEVDB/datafile/o1_mf_idx_bss7s7gp_.dbf tag=TAG20150708T115355 RECID=13 STAMP=884519720
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:01
channel ORA_DISK_1: starting datafile copy
input datafile file number=00004 name=/u01/app/oracle/oradata/devdb/users01.dbf
output file name=/u01/app/oracle/fast_recovery_area/DEVDB/datafile/o1_mf_users_bss7s8mb_.dbf tag=TAG20150708T115355 RECID=14 STAMP=884519720
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:01
Finished backup at 2015/07/08 11:55:21
Starting Control File and SPFILE Autobackup at 2015/07/08 11:55:21
piece handle=/u01/app/oracle/fast_recovery_area/DEVDB/autobackup/2015_07_08/o1_mf_s_884519721_bss7sbdk_.bkp comment=NONE
Finished Control File and SPFILE Autobackup at 2015/07/08 11:55:22
备份了数据库中所有的数据文件（包括undo，其实undo也是数据文件）。但是backup database as copy时，并不会备份控制文件和spfile。最后一段备份控制文件与参数文件是因为我们配置了控制文件自动备份功能。
RMAN> backup as copy tablespace EXAMPLE;
Starting backup at 2015/07/08 12:26:58
using target database control file instead of recovery catalog
allocated channel: ORA_DISK_1
channel ORA_DISK_1: SID=1 device type=DISK
channel ORA_DISK_1: starting datafile copy
input datafile file number=00005 name=/u01/app/oracle/oradata/devdb/example01.dbf
output file name=/u01/app/oracle/fast_recovery_area/DEVDB/datafile/o1_mf_example_bss9nmnv_.dbf tag=TAG20150708T122659 RECID=15 STAMP=884521632
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:15
Finished backup at 2015/07/08 12:27:14
Starting Control File and SPFILE Autobackup at 2015/07/08 12:27:14
piece handle=/u01/app/oracle/fast_recovery_area/DEVDB/autobackup/2015_07_08/o1_mf_s_884521634_bss9o37t_.bkp comment=NONE
Finished Control File and SPFILE Autobackup at 2015/07/08 12:27:15
RMAN> backup as copy datafile '/u01/app/oracle/oradata/devdb/example01.dbf';
Starting backup at 2015/07/08 12:28:59
using channel ORA_DISK_1
channel ORA_DISK_1: starting datafile copy
input datafile file number=00005 name=/u01/app/oracle/oradata/devdb/example01.dbf
output file name=/u01/app/oracle/fast_recovery_area/DEVDB/datafile/o1_mf_example_bss9rcv9_.dbf tag=TAG20150708T122859 RECID=16 STAMP=884521750
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:15
Finished backup at 2015/07/08 12:29:14
Starting Control File and SPFILE Autobackup at 2015/07/08 12:29:15
piece handle=/u01/app/oracle/fast_recovery_area/DEVDB/autobackup/2015_07_08/o1_mf_s_884521755_bss9rv8v_.bkp comment=NONE
Finished Control File and SPFILE Autobackup at 2015/07/08 12:29:16
RMAN> backup as copy current controlfile;
Starting backup at 2015/07/08 12:33:34
using channel ORA_DISK_1
channel ORA_DISK_1: starting datafile copy
copying current control file
output file name=/u01/app/oracle/fast_recovery_area/DEVDB/controlfile/o1_mf_TAG20150708T123334_bssb0yj4_.ctl tag=TAG20150708T123334 RECID=17 STAMP=884522014
channel ORA_DISK_1: datafile copy complete, elapsed time: 00:00:01
Finished backup at 2015/07/08 12:33:35
Starting Control File and SPFILE Autobackup at 2015/07/08 12:33:35
piece handle=/u01/app/oracle/fast_recovery_area/DEVDB/autobackup/2015_07_08/o1_mf_s_884522015_bssb0zrf_.bkp comment=NONE
Finished Control File and SPFILE Autobackup at 2015/07/08 12:33:36
RMAN> backup as copy archivelog all;
Starting backup at 2015/07/08 12:34:54
current log archived
using channel ORA_DISK_1
channel ORA_DISK_1: starting archived log copy
input archived log thread=1 sequence=16 RECID=7 STAMP=884486041
output file name=/u01/app/oracle/fast_recovery_area/DEVDB/archivelog/2015_07_08/o1_mf_1_16_bssb3h9w_.arc RECID=15 STAMP=884522095
channel ORA_DISK_1: archived log copy complete, elapsed time: 00:00:01
channel ORA_DISK_1: starting archived log copy
input archived log thread=1 sequence=17 RECID=8 STAMP=884486144
output file name=/u01/app/oracle/fast_recovery_area/DEVDB/archivelog/2015_07_08/o1_mf_1_17_bssb3jdy_.arc RECID=16 STAMP=884522096
channel ORA_DISK_1: archived log copy complete, elapsed time: 00:00:01
channel ORA_DISK_1: starting archived log copy
input archived log thread=1 sequence=18 RECID=9 STAMP=884486148
output file name=/u01/app/oracle/fast_recovery_area/DEVDB/archivelog/2015_07_08/o1_mf_1_18_bssb3khz_.arc RECID=17 STAMP=884522097
channel ORA_DISK_1: archived log copy complete, elapsed time: 00:00:01
channel ORA_DISK_1: starting archived log copy
input archived log thread=1 sequence=19 RECID=10 STAMP=884486151
output file name=/u01/app/oracle/fast_recovery_area/DEVDB/archivelog/2015_07_08/o1_mf_1_19_bssb3ll4_.arc RECID=18 STAMP=884522098
channel ORA_DISK_1: archived log copy complete, elapsed time: 00:00:01
channel ORA_DISK_1: starting archived log copy
input archived log thread=1 sequence=20 RECID=11 STAMP=884486169
output file name=/u01/app/oracle/fast_recovery_area/DEVDB/archivelog/2015_07_08/o1_mf_1_20_bssb3mnx_.arc RECID=19 STAMP=884522099
channel ORA_DISK_1: archived log copy complete, elapsed time: 00:00:01
channel ORA_DISK_1: starting archived log copy
input archived log thread=1 sequence=21 RECID=12 STAMP=884486468
output file name=/u01/app/oracle/fast_recovery_area/DEVDB/archivelog/2015_07_08/o1_mf_1_21_bssb3nqm_.arc RECID=20 STAMP=884522100
channel ORA_DISK_1: archived log copy complete, elapsed time: 00:00:01
channel ORA_DISK_1: starting archived log copy
input archived log thread=1 sequence=22 RECID=13 STAMP=884486525
output file name=/u01/app/oracle/fast_recovery_area/DEVDB/archivelog/2015_07_08/o1_mf_1_22_bssb3otp_.arc RECID=21 STAMP=884522101
channel ORA_DISK_1: archived log copy complete, elapsed time: 00:00:01
channel ORA_DISK_1: starting archived log copy
input archived log thread=1 sequence=23 RECID=14 STAMP=884522094
output file name=/u01/app/oracle/fast_recovery_area/DEVDB/archivelog/2015_07_08/o1_mf_1_23_bssb3py8_.arc RECID=22 STAMP=884522103
channel ORA_DISK_1: archived log copy complete, elapsed time: 00:00:01
Finished backup at 2015/07/08 12:35:03
Starting Control File and SPFILE Autobackup at 2015/07/08 12:35:04
piece handle=/u01/app/oracle/fast_recovery_area/DEVDB/autobackup/2015_07_08/o1_mf_s_884522104_bssb3r69_.bkp comment=NONE
Finished Control File and SPFILE Autobackup at 2015/07/08 12:35:05
另外有需要云服务器可以了解下创新互联cdcxhl.cn，海内外云服务器15元起步，三天无理由+7*72小时售后在线，公司持有idc许可证，提供“云服务器、裸金属服务器、高防服务器、香港服务器、美国服务器、虚拟主机、免备案服务器”等云主机租用服务以及企业上云的综合解决方案，具有“安全稳定、简单易用、服务可用性高、性价比高”等特点与优势，专为企业上云打造定制，能够满足用户丰富、多元化的应用场景需求。
分享题目：Oracle学习之RMAN（五）镜像copy-创新互联
标题来源：
http://cqcxhl.com/article/dpcdej.html
重庆分公司
