1、恢复过程查看的试图：
1）v$recovery_file:查看需要恢复的datafile
2）v$recovery_log:查看recover需要的redo日志
3）v$archived_log:查看已经归档的日志
2、手工完全恢复
实验一：所有数据文件和控制文件都丢失
1）先将控制文件dump到trace中
SQL> alter database backup controlfile to trace as ‘/u01/app/oracle/admin/EMREP/udump/haha.trc‘;
2）创建实验表
SQL> create table emp1 as select * from scott.emp;
插入数据提交并归档
SQL> insert into emp1 select * from scott.emp;
SQL> commit;
SQL> alter system archive log current;
插入数据只提交
SQL> insert into emp1 select * from scott.emp;
SQL> commit;
不提交不归档
SQL> insert into emp1 select * from scott.emp;
3）模拟断电，破会数据文件和控制文件
SQL> shutdown abort
[[email protected] hot_bak]$ cd /u01/app/oracle/oradata/EMREP/
[[email protected] EMREP]$ ls
control01.ctl example01.dbf redo01.log sysaux01.dbf undotbs01.dbf
control02.ctl gguser.dbf redo02.log system01.dbf users01.dbf
control03.ctl goldengate01.dbf redo03.log temp01.dbf
[[email protected] EMREP]$ rm *.dbf
[[email protected] EMREP]$ rm *.ctl
4）启动数据库失败
SQL> startup
ORACLE instance started.
Total System Global Area 608174080 bytes
Fixed Size 1220844 bytes
Variable Size 197136148 bytes
Database Buffers 406847488 bytes
Redo Buffers 2969600 bytes
ORA-00205: error in identifying control file, check alert log for more info
5）恢复解决：
（1）重建控制文件，因为日志没有丢失，所以这里用NORESETLOGS
[[email protected] udump]$ more haha.trc
CREATE CONTROLFILE REUSE DATABASE "EMREP" NORESETLOGS FORCE LOGGING ARCHIVELOG
MAXLOGFILES 16
MAXLOGMEMBERS 3
MAXDATAFILES 100
MAXINSTANCES 8
MAXLOGHISTORY 292
LOGFILE
GROUP 1 ‘/u01/app/oracle/oradata/EMREP/redo01.log‘ SIZE 50M,
GROUP 2 ‘/u01/app/oracle/oradata/EMREP/redo02.log‘ SIZE 50M,
GROUP 3 ‘/u01/app/oracle/oradata/EMREP/redo03.log‘ SIZE 50M
-- STANDBY LOGFILE
DATAFILE
‘/u01/app/oracle/oradata/EMREP/system01.dbf‘,
‘/u01/app/oracle/oradata/EMREP/undotbs01.dbf‘,
‘/u01/app/oracle/oradata/EMREP/sysaux01.dbf‘,
‘/u01/app/oracle/oradata/EMREP/users01.dbf‘,
‘/u01/app/oracle/oradata/EMREP/example01.dbf‘,
‘/u01/app/oracle/oradata/EMREP/goldengate01.dbf‘,
‘/u01/app/oracle/oradata/EMREP/gguser.dbf‘
CHARACTER SET WE8ISO8859P1
;
重建报错，我们需要先转储备份的数据文件
[[email protected] hot_bak]$ cp * /u01/app/oracle/oradata/EMREP/
[[email protected] hot_bak]$ cp control01.ctl /u01/app/oracle/oradata/EMREP/control01.ctl
[[email protected] hot_bak]$ cp control01.ctl /u01/app/oracle/oradata/EMREP/control02.ctl
[[email protected] hot_bak]$ cp control01.ctl /u01/app/oracle/oradata/EMREP/control03.ctl
再次重建成功；
查看scn号发现不一致
SQL> select file#,checkpoint_change# from v$datafile;
1 998993
2 998993
3 998993
4 998993
5 998993
6 998993
7 998993
SQL> select file#,checkpoint_change# from v$datafile_header;
1 998253
2 998289
3 998313
4 998340
5 998360
6 998384
7 998410
需要恢复数据库
SQL> recover database;
Media recovery complete.
SQL> alter database open;
SQL> select count(*) from emp1;
42
数据恢复到最后一次提交。
实验二：只有数据文件丢失了
1）创建实验环境
SQL> create table emp2 as select * from scott.emp;
SQL> insert into emp2 select * from scott.emp;
SQL> commit;
SQL> alter system archive log current;
SQL> insert into emp2 select * from scott.emp;
SQL> commit;
SQL> insert into emp2 select * from scott.emp;
SQL> select count(*) from emp2;
56
2）模拟断电，破坏试验
SQL> shutdown abort
ORACLE instance shut down.
删除所有的数据文件
[[email protected] EMREP]$ ls
control01.ctl example01.dbf redo01.log sysaux01.dbf users01.dbf
control02.ctl gguser.dbf redo02.log system01.dbf
control03.ctl goldengate01.dbf redo03.log undotbs01.dbf
[[email protected] EMREP]$ rm *.dbf
3）启动失败
SQL> startup
ORACLE instance started.
Total System Global Area 608174080 bytes
Fixed Size 1220844 bytes
Variable Size 197136148 bytes
Database Buffers 406847488 bytes
Redo Buffers 2969600 bytes
Database mounted.
ORA-01157: cannot identify/lock data file 1 - see DBWR trace file
ORA-01110: data file 1: ‘/u01/app/oracle/oradata/EMREP/system01.dbf‘
查看需要恢复的数据文件
SQL> select file#,error from v$recover_file;
1 FILE NOT FOUND
2 FILE NOT FOUND
3 FILE NOT FOUND
4 FILE NOT FOUND
5 FILE NOT FOUND
6 FILE NOT FOUND
7 FILE NOT FOUND
SQL> select file#,name from v$datafile;
1 /u01/app/oracle/oradata/EMREP/system01.dbf
2 /u01/app/oracle/oradata/EMREP/undotbs01.dbf
3 /u01/app/oracle/oradata/EMREP/sysaux01.dbf
4 /u01/app/oracle/oradata/EMREP/users01.dbf
5 /u01/app/oracle/oradata/EMREP/example01.dbf
6 /u01/app/oracle/oradata/EMREP/goldengate01.dbf
7 /u01/app/oracle/oradata/EMREP/gguser.dbf
转储备份：
[[email protected] hot_bak]$ cp *.dbf /u01/app/oracle/oradata/EMREP/
恢复：
SQL> recover database;
ORA-00279: change 998253 generated at 07/27/2014 13:20:11 needed for thread 1
ORA-00289: suggestion : /home/oracle/EMREP/1_23_839513627.dbf
ORA-00280: change 998253 for thread 1 is in sequence #23
Specify log: {<RET>=suggested | filename | AUTO | CANCEL}
auto ---让系统自己找需要的日志
Log applied.
Media recovery complete.
SQL> alter database open;
SQL> select count(*) from emp2;
42
数据恢复到最后一次的提交。
手工恢复