今天有朋友问，到底RMAN里面的命令delete expired和delete obsolete有什么区别？ 先来看一下官方文档中的解释。via Backup and Recovery User Guide delete exipired If you run CROSSCHECK, and if RMAN cannot locate the files, then it updates their records in the RMAN repository to EXPIRED status. You can then use the DELETE EXPIRED command to remove records of expired backups and copies from the RMAN repository. delete…
Tag: RMAN
RMAN Compressed Backupset
在Oracle10g就已经推出了Compressed Backupset。 There is some CPU overhead associated with compressing backup sets. If the database being backed up is running at or near its maximum load, you may find the overhead from using AS COMPRESSED BACKUPSET unacceptable. In most other circumstances, compressing backupsets saves enough disk space to be worth the CPU overhead. 今天在自己机器上的Oracle 11.1.0.6版本中测试了一下，压缩效果还是很让人满意的，不但存储空间变小，甚至备份所需要的时间也有所加快。…
利用RMAN转移数据文件
将数据文件从文件系统转移为裸设备，很简单，记录一下操作。 1. 从v$datafile中找到需要转换的数据文件file# 2. 从dba_data_files中找到数据文件所在的表空间名称，因为restore之前要将相关表空间offline才可以 3. 创建好相应的目的裸设备 4. 数据库必须处于归档状态 在RMAN中运行如下命令： run{ sql “alter tablespace ADMASDB_DEFAULT offline”; allocate channel d1 TYPE DISK; set newname for datafile 136 to ‘/home/oracle/oradata/admas/roralv08’; set newname for datafile 164 to ‘/home/oracle/oradata/admas/roralv5G_3’; restore datafile 136; restore datafile 164; switch datafile all; recover datafile 136; recover datafile 164; sql “alter tablespace ADMASDB_DEFAULT online”;…