oracle课堂随笔--第二十五天

通过不完全恢复解决用户的误操作：

SQL> archive log list

备份前工作：

SQL> create table t1(x varchar2(50)) tablespace users;

SQL> insert into t1 values ('before backup');

SQL> commit;

备份：

RMAN> backup database tag 'weekend_DB_full_backup';

备份后：

SQL> insert into t1 values ('after backup, before delete');

SQL> commit;

误操作：

SQL> select sysdate from dual;

SQL> select dbms_flashback.get_system_change_number from dual;查看号码

SQL> delete t1;

SQL> commit;

SQL> create table after_delete (x int); 正确的操作

SQL> insert into after_delete values (1);

SQL> commit;

恢复：

RMAN> run {

startup force mount;

set until scn= 1806683;

restore database;

recover database;

alter database open resetlogs;

}

set until time=’2015-10-26 11:13:23’; 基于时间点恢复

SQL> select * from t1;

SQL> select * from after_delete; 丢失

SQL> select group#, sequence#, status, archived from v$log;

通过不完全恢复解决归档日志不连续：

SQL> archive log list

备份前：

SQL> create table t1(x varchar2(50)) tablespace users;

SQL> insert into t1 values ('before backup');

SQL> commit;

备份： 

RMAN> backup database tag 'weekend_DB_full_backup';

备份后：

SQL> select GROUP#, SEQUENCE#, STATUS, archived from v$log;

SQL> insert into t1 values ('after backup, logseq 1, archived');

SQL> commit;

SQL> alter system switch logfile;

SQL> insert into t1 values ('after backup, logseq 2, archived');

SQL> commit;

SQL> alter system switch logfile;

SQL> insert into t1 values ('after backup, logseq 3, archived');

SQL> commit;

SQL> alter system switch logfile;

SQL> insert into t1 values ('after backup, logseq 4, archived');

SQL> commit;

SQL> alter system switch logfile;

SQL> insert into t1 values ('after backup, logseq 5, current');

SQL> commit;

SQL> alter system checkpoint;

故障：

SQL> shutdown abort

$ rm /u01/app/oracle/oradata/orcl/users01.dbf

$rm/u01/app/oracle/fast_recovery_area/ORCL/archivelog/2016_03_01/o1_mf_1_5_cfbcxo84_.arc

恢复：

SQL> startup

先尝试只恢复一个数据文件失败。

RMAN> run {

startup force mount;

set until sequence 4;

restore database;

recover database;

alter database open resetlogs;

}

SQL> select * from t1;