归档模式关闭数据库的恢复
欢迎进入Oracle社区论坛,与200万技术人员互动交流 >>进入 一。非归档模式关闭数据库的恢复 1.shutdown immediate; 关闭数据库 2.使用操作系统命令拷贝最新的备份(数据文件和控制文件,如果备份了日志文件) 3.进行不完全恢复recover database until cancel
欢迎进入Oracle社区论坛,与200万技术人员互动交流 >>进入
一。非归档模式关闭数据库的恢复
1.shutdown immediate; 关闭数据库
2.使用操作系统命令拷贝最新的备份(数据文件和控制文件,如果备份了日志文件)
3.进行不完全恢复recover database until cancel using backup;
4.重置日志打开数据库alter database open resetlogs;
二。数据文件离线或者表空间离线的恢复
SQL> create table t1 tablespace tbs_sf as select * from dba_objects; --创建测试表到指定表空间
SQL> select file_id,file_name from dba_data_files where TABLESPACE_NAME='TBS_SF'; --可以看到数据文件时26号
FILE_ID FILE_NAME
---------- --------------------------------------------------
26 /database/oradata/skyread/sf01.dbf
SQL> alter database datafile 26 offline drop; --数据文件脱机,这里是模拟故障,恢复的时候相当于从备份拷贝一个新文件回来
Database altered.
SQL> select count(*) from t1; --可见无法查看该表空间的表
select count(*) from t1
*
ERROR at line 1:
ORA-00376: file 26 cannot be read at this time
ORA-01110: data file 26: '/database/oradata/skyread/sf01.dbf'
SQL> select hxfil file_id,fhsta status,fhscn scn,fhrba_seq seq from x$kcvfh where hxfil=26;
FILE_ID STATUS SCN SEQ
---------- ---------- ---------------- ----------
26 4 122693804311 2
SQL> select GROUP#,BYTES,ARCHIVED,STATUS,SEQUENCE# from v$log; --可见红色的日志没有被覆盖,可以进行恢复
GROUP# BYTES ARC STATUS SEQUENCE#
---------- ---------- --- ---------------- ----------
1 536870912 YES INACTIVE 1
2 536870912 NO CURRENT 2
3 536870912 YES UNUSED 0
4 536870912 YES UNUSED 0
5 536870912 YES UNUSED 0
SQL> recover datafile 26; --进行恢复
Media recovery complete.
SQL> alter database datafile 26 online;
Database altered.
SQL> select count(*) from t1;
COUNT(*)
----------
50483
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