ORACLE - RMAN快速入门指南(5)

# Database can now be opened normally. ALTER DATABASE OPEN; #----------------------------- 3、OS 备份的恢复 备份： OS copy 恢复：

OS copy回来即可，要注意的是这个备份必须是最新有效的。 二、Database的恢复

A、To restore the database from host_a to host_b with the same file system #此处使用recovery catalog；

#如果不是catalog mode，就用OS COPY直接将control file #copy过来并mount database。

1、copy the init.ora file from host_a to host_b using o/s utility 2、rman target sys/sys@host_b catalog rman/rman@rcat 3、startup nomount 4、run {

allocate channel c1 type disk;

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restore controlfile; sql ‘alter database mount’; }

5、select min(scn) from (

select max(next_change#) scn from v$archived_log group by thread#); 6、run {

set until scn=500; #use appropriate SCN for incomplete recovery allocate channel c1 type ‘sbt_type’; restore database; recover database;

sql ‘alter database open resetlogs’; }

B、To restore the database from host_a to host_b with a different filesystem

步骤和A差不多，不同的是在启动数据库之前要修改init.ora文件中所有和路径相关的参数，如：*_DEST，*_PATH 等。然后执行如下脚本： run {

set until scn=500;

allocate channel c1 type disk;

set newname for datafile 1 to ‘/disk’/%U’; set newname for datafile 2 to ‘/disk’/%U’; set newname for datafile 3 to ‘/disk’/%U’; set newname for datafile 4 to ‘/disk’/%U’; set newname for datafile 5 to ‘/disk’/%U’; set newname for datafile 6 to ‘/disk’/%U’; set newname for datafile 7 to ‘/disk’/%U’; sql ‘alter database mount’; restore database;

switch datafile all; #points the control file to the renamed datafiles recover database; .... ....

sql ‘alter database open resetlogs’; }

三、Tablespace and datafile的恢复 run {

allocate channel c1 type disk;

sql ‘alter tablespace users offline immediate’; #must be in archive log mode #如下改变datafile位置

set newname for datafile 'c:/oracle/oradata/ora/users01.dbf' to 'c:/oracle/oradata/orabk/user01.dbf';

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restore tablespace users; switch datafile all; recover tablespace users; sql ‘alter tablespace users online’; }

如果不在archive log mode下，执行以上SQL时会出错：ORA-01145。你将不得不shutdown。 四、关于set until 选项

set until后面可以跟time、scn和logseq三个不同的选项，当数据库运行在noarchivelog mode 下时可以使用until cancel选项进行数据库的不完全恢复。所有这些的具体过程和以上 的数据库恢复都差不多，不再赘述。

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