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探索Oracle之RMAN_04非一致性备份

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Jun 07, 2016 pm 05:13 PM

探索Oracle之RMAN_04非一致性备份，操作非常的简单。只需要一条很短的命令即可完成，但是如果要创建一正式库的备份，一般不建议用

在上一篇中提到了数据库的一致性备份（见探索Oracle之RMAN_03非一致性备份），，操作非常的简单。只需要一条很短的命令即可完成，但是如果要创建一正式库的备份，一般不建议用一致性备份，也不建议用很简单的名来完成。而是更多的采用脚本实现非一致性备份，这样将可通过backup+archive log+redo有效的将数据恢复到最近一次改变的状态，可以达到数据的丢失最小化。

相关阅读：

探索Oracle之RMAN_01概念

探索Oracle之RMAN_02基本使用

探索Oracle之RMAN_03非一致性备份

探索Oracle之RMAN_04非一致性备份

探索Oracle之RMAN_05增量备份

探索Oracle之RMAN_06备份策略

创建非一致性备份

并且可以在数据库打开并不影响业务的情况下完成数据的备份工作；那么这样的备份将是不一致性的备份，那么如果要恢复可以通过backup+archive log+redo来恢复到最近一次日志切换时候的数据，而不是最后一次备份时候的数据。

1.1检查归档状态：

SQL> archive log list;

Database log mode No Archive Mode

Automaticarchival Disabled

Archivedestination USE_DB_RECOVERY_FILE_DEST

Oldest onlinelog sequence 9

Current logsequence 11

SQL>

必须打开归档归档

状态

Databaseclosed.

Databasedismounted.

ORACLE instanceshut down.

SQL> startup mount;

ORACLE instancestarted.

Total SystemGlobal Area 285212672 bytes

Fixed Size 1218968 bytes

VariableSize 79693416 bytes

DatabaseBuffers 197132288 bytes

RedoBuffers 7168000 bytes

Databasemounted.

Databasealtered.

SQL> colinstance_name format a15

INSTANCE_NAME STATUS

---------------------------------------

WWL OPEN

SQL>

SQL> archive log list; ------查看归档状态，已经是归档状态了

Database log mode Archive Mode

Automatic archival Enabled

Archivedestination USE_DB_RECOVERY_FILE_DEST

Oldest onlinelog sequence 9

Next logsequence to archive 11

Current logsequence 11

SQL>

1.2执行备份 (执行备份命令实际上是跟一致性备份是一样的)

1.2.1 备份数据库

RMAN> backup database;

Starting backupat 23-MAY-12

allocatedchannel: ORA_DISK_1

channelORA_DISK_1: sid=145 devtype=DISK

channelORA_DISK_1: starting full datafile backupset

channelORA_DISK_1: specifying datafile(s) in backupset

input datafilefno=00001 name=/DBData/WWL/system01.dbf

input datafilefno=00003 name=/DBData/WWL/sysaux01.dbf

input datafilefno=00002 name=/DBData/WWL/undotbs01.dbf

input datafilefno=00004 name=/DBData/WWL/users01.dbf

channelORA_DISK_1: starting piece 1 at 23-MAY-12

channelORA_DISK_1: finished piece 1 at 23-MAY-12

piecehandle=/DBBak/bak_WWL_05_23_0anbmtkr_1_1 tag=TAG20120523T121210 comment=NONE

channelORA_DISK_1: backup set complete, elapsed time: 00:01:46

Finished backupat 23-MAY-12

Starting ControlFile and SPFILE Autobackup at 23-MAY-12

piecehandle=/DBSoft/product/10.2.0/db_1/dbs/c-5520179-20120523-00 comment=NONE

Finished ControlFile and SPFILE Autobackup at 23-MAY-12

RMAN>

linux

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