oracle控制文件的恢复有备份、有控制文件创建脚本、都没有3
控制文件的恢复分两步: 1.从备份还原; 2.用重做日志恢复。 一、有备份的控制文件恢复 控制文件按备份的时间跨度分类: 1).在线镜像备份:当前控制文件,即control_files初始化参数所指向的除去损坏的控制文件以外的控制文件; 2).结构备份:控制文件备份后
控制文件的恢复分两步:
1.从备份还原;
2.用重做日志恢复。
一、有备份的控制文件恢复
控制文件按备份的时间跨度分类:
1).在线镜像备份:当前控制文件,即control_files初始化参数所指向的除去损坏的控制文件以外的控制文件;
2).结构备份:控制文件备份后,数据库的结构没发生变化(例如添加删除表空间、重做日志文件);
3).历史备份:控制文件备份后,数据库的结构发生了变化。
发现控制文件损坏后
1.SQL>shutdown abort
2.SQL>startup
提示错误ora-00205控制文件出错或ora-00227控制文件存在坏块,数据库启动到started状态
3.首先看是否存在在线镜像备份,若存在,则按以下步骤恢复:
1)查看警告日志,确定哪些控制文件损坏了;
2)将正确的控制文件复制到损坏了的控制文件的位置上;
3)SQL>alter database mount;
4)SQL>alter database open;
否则,看是否存在结构备份,若存在,按以下步骤恢复:
1)进入rman:rman target/
2)从备份中还原控制文件
RMAN>restore controlfile from autobackup;(自动备份)
或
RMAN>restore
controlfile from '手动备份的控制文件的位置';(手动备份)
3)设置数据库到mount状态
RMAN>alter database mount;
4)介质恢复
RMAN>recover database;
5)RMAN>alter database open resetlogs;
如果只有历史备份:
使用历史备份后会出现不一致,以下2种情况需要手动修复不一致:
1)备份控制文件中具有某个数据文件或表空间的信息,但实际不存在
2)备份中没有某个在线日志组的信息,但实际是存在的(在恢复时用recover database using backup controlfile在提示中输入相应的在线日志的路径)
A、对于自动修复不一致的情况,其恢复步骤与结构备份的手动备份相同
B、备份控制文件中具有某个数据文件或表空间的信息,但实际不存在
1)进入rman:rman target/
2)从备份中还原控制文件
RMAN>restore controlfile from '手动备份的控制文件的位置';(手动备份)
3)设置数据库到mount状态
RMAN>alter database mount;
4)此时不能直接回复数据库,而应使恢复操作不理睬这个丢失的数据文件或表空间
数据文件:
SQL>alter database datafile 文件号 offline;(数据文件)
恢复数据库
SQL>recover database using backup controlfile;
表空间(包括表空间内所有数据文件):
SQL>recover database skip tablespace 表空间名;
5)RMAN>alter database open resetlogs;
二、没有控制文件备份,但对控制文件做了追踪备份,即有创建控制文件的脚本
1.SQL>shutdown abort
2.SQL>startup
提示错误ora-00205控制文件出错或ora-00227控制文件存在坏块,数据库启动到started状态
3.找到备份的trace文件,并将其中创建控制文件的脚本提取出来createctl.sql
4.执行脚本createctl.sql
SQL>@createctl.sql
三、没有控制文件的备份和trace备份,此时需要手工创建控制文件
1.SQL>shutdown abort
2.SQL>startup
提示错误ora-00205控制文件出错或ora-00227控制文件存在坏块,数据库启动到started状态
3.手工创建控制文件SQL>create controlfile reuse(/set) database "数据库名" noresetlogs(/resetlogs 仅当online logs损坏的情况下才使用) noarchivelog
MAXLOGFILES 16
MAXLOGMEMBERS 3
MAXDATAFILES 100
MAXINSTANCES 8
MAXLOGHISTORY 4672
LOGFILE
GROUP 1 '重做日志1的目录' SIZE 50M,
GROUP 2 '重做日志2的目录' SIZE 50M,
GROUP 3 '重做日志3的目录' SIZE 50M
DATAFILE
'数据文件目录/system01.dbf',
'数据文件目录/undotbs01.dbf',
'数据文件目录/sysaux01.dbf',
'数据文件目录/users01.dbf',
'数据文件目录/info01.dbf' (不包括temp文件)
CHARACTER SET ZHS16GBK
;
提示创建成功
4.介质恢复
sql>RECOVER DATABASE
sql>ALTER DATABASE OPEN;
sql>ALTER TABLESPACE TEMP ADD TEMPFILE 'temp文件目录/temp01.dbf'
SIZE 1244667904 REUSE AUTOEXTEND ON NEXT 655360 MAXSIZE 32767M;
最后恢复完成后记得备份控制文件
备份控制文件
ALTER DATABASE BACKUP CONTROLFILE TO 'F:\ORACLE\BACKUP\TEST.BAK';
alter database backup controlfile to trace as '目录';--生成创建控制文件的脚本,可通过show parameter user_dump_dest查看。

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