Oracle数据库手滑删错数据教你如何挽救

2、模拟测试场景

主库开启归档模式

--设置归档路径
alter system set log_archive_dest_1='LOCATION=/archivelog';
--重启开启归档模式
shutdown immediate
startup mount
alter database archivelog；
--打开数据库
alter database open;

创建测试数据

sqlplus / as sysdba
--创建表空间
create tablespace lucifer datafile '/oradata/orcl/lucifer01.dbf' size 10M autoextend off;
create tablespace ltest datafile '/oradata/orcl/ltest01.dbf' size 10M autoextend off;
--创建用户
create user lucifer identified by lucifer;
grant dba to lucifer;
--创建表
conn lucifer/lucifer
create table lucifer(id number not null,name varchar2(20)) tablespace lucifer;
--插入数据
insert into lucifer values(1,'lucifer');
insert into lucifer values(2,'test1');
insert into lucifer values(3,'test2');
commit;

进行数据库全备

run {
allocate channel c1 device type disk;
allocate channel c2 device type disk;
crosscheck backup;
crosscheck archivelog all; 
sql"alter system switch logfile";
delete noprompt expired backup;
delete noprompt obsolete device type disk;
backup database include current controlfile format '/backup/backlv0_%d_%T_%t_%s_%p';
backup archivelog all DELETE INPUT;
release channel c1;
release channel c2;
}

模拟数据修改

sqlplus / as sysdba
conn lucifer/lucifer
delete from lucifer where id=1;
update lucifer set name='lucifer' where id=2;
commit;

注意：为了模拟客户环境，假设无法通过UNDO快照找回，当前删除时间点为：2021/06/17 18:10:00。

如果使用UNDO快照，比较方便：

--查找UNDO快照数据是否正确
select * from lucifer.lucifer as of timestamp to_timestamp('2021-06-17 18:05:00','YYYY-MM-DD HH24:MI:SS');
--将UNDO快照数据捞至新建表中
create table lucifer.lucifer_0617 as select * from lucifer.lucifer as of timestamp to_timestamp('2021-06-17 18:05:00','YYYY-MM-DD HH24:MI:SS');

四、RMAN完整恢复过程

主库查询误更新数据表对应的表空间和无需恢复的表空间

--查询误更新数据表对应表空间
select owner,tablespace_name from dba_segments where segment_name='LUCIFER';
--查询所有表空间
select tablespace_name from dba_tablespaces;

主库拷贝参数文件，密码文件至新主机，根据新主机修改参数文件和创建新实例所需目录

##生成pfile参数文件
sqlplus / as sysdba
create pfile='/home/oracle/pfile.ora' from spfile;
##拷贝至新主机
su - oracle
scp /home/oracle/pfile.ora 10.211.55.112:/tmp
scp $ORACLE_HOME/dbs/orapworcl 10.211.55.112:$ORACLE_HOME/dbs
###新主机根据实际情况修改参数文件并且创建目录
mkdir -p /u01/app/oracle/admin/orcl/adump
mkdir -p /oradata/orcl/
mkdir -p /archivelog
chown -R oracle:oinstall /archivelog
chown -R oracle:oinstall /oradata

新主机使用修改后的参数文件打开数据库实例到nomount状态

sqlplus / as sysdba
startup nomount pfile='/tmp/pfile.ora';

主库拷贝备份的控制文件至新主机，新主机使用RMAN恢复控制文件，并且MOUNT新实例

rman target /
list backup of controlfile;
##拷贝备份文件至新主机
scp /backup/backlv0_ORCL_20210617_107548592* 10.211.55.112:/tmp
scp /u01/app/oracle/product/11.2.0/db/dbs/0c01l775_1_1 10.211.55.112:/tmp
##新主机恢复控制文件并开启到mount状态
rman target /
restore controlfile from '/tmp/backlv0_ORCL_20210617_1075485924_9_1';
alter database mount;

通过 list backup of controlfile; 可以看到控制文件位置。

新主机RESTORE TABLESPACE恢复至时间点 2021/06/17 18:06:00

##新主机注册备份集
rman target /
catalog start with '/tmp/backlv0_ORCL_20210617_107548592';
crosscheck backup;
delete noprompt expired backup;
delete noprompt obsolete device type disk;
##恢复表空间LUCIFER和系统表空间，指定时间点 `2021/06/17 18:06:00`
run {
sql 'alter session set nls_date_format="yyyy-mm-dd hh24:mi:ss"';
set until time '2021-06-17 18:06:00';
allocate channel ch01 device type disk;
allocate channel ch02 device type disk;
restore tablespace SYSTEM,SYSAUX,UNDOTBS1,USERS,LUCIFER;
release channel ch01;
release channel ch02;
}

新主机RECOVER DATABASE SKIP TABLESPACE恢复至时间点 2021/06/17 18:06:00

rman target /
run {
sql 'alter session set nls_date_format="yyyy-mm-dd hh24:mi:ss"';
set until time '2021-06-17 18:06:00';
allocate channel ch01 device type disk;
recover database skip tablespace LTEST,EXAMPLE;
release channel ch01;
}

这里有一个小BUG：客户环境是Windows，执行这一步最后报错，手动offline数据文件依然无法开启数据库。

解决方案：

--将恢复跳过的表空间都offline drop掉，执行以下查询结果
select 'alter database datafile '|| file_id ||' offline drop;' from dba_data_files where tablespace_name in ('LTEST','EXAMPLE');
--再次开启数据库
alter database open read only;

注意：如果显示缺归档日志，可以参考如下步骤:

##查询恢复需要的归档日志号时间 
alter session set nls_date_format="yyyy-mm-dd hh24:mi:ss"; 
select first_time,sequence# from v$archived_log where sequence#='7';

##通过备份RESTORE吐出所需的归档日志 
rman target / 
catalog start with '/tmp/0c01l775_1_1'; 
crosscheck archivelog all; 
run { 
allocate channel ch01 device type disk; 
SET ARCHIVELOG DESTINATION TO '/archivelog';
restore ARCHIVELOG SEQUENCE 7; 
release channel ch01; 
}

##再次recover进行恢复至指定时间点 2021-06-17 18:06:00 
run { 
sql 'alter session set nls_date_format="yyyy-mm-dd hh24:mi:ss"'; 
set until time '2021-06-17 18:06:00'; 
allocate channel ch01 device type disk; 
recover database skip tablespace LTEST,EXAMPLE; 
release channel ch01; 
} 

新主机实例开启到只读模式

sqlplus / as sysdba
alter database open read only;

确认新主机实例的表数据是否正确

select * from lucifer.lucifer;

注意：若不正确则重复 第7步 调整时间点慢慢往 2021/06/17 18:10:00 推进恢复:

##关闭数据库
sqlplus / as sysdba
shutdown immediate;

##开启数据库到mount状态
startup mount pfile='/tmp/pfile.ora';

##重复 第7步，往前推进1分钟，调整时间点为 `2021/06/08 18:07:00`
rman target /
run {
sql 'alter session set nls_date_format="yyyy-mm-dd hh24:mi:ss"';
set until time '2021-06-17 18:07:00';
allocate channel ch01 device type disk;
recover database skip tablespace LTEST,EXAMPLE;
release channel ch01;
}

主库创建连通新主机实例的DBLINK，通过DBLINK从新主机实例捞取表数据

sqlplus / as sysdba
CREATE PUBLIC DATABASE LINK ORCL112
CONNECT TO lucifer
IDENTIFIED BY lucifer
USING '(DESCRIPTION_LIST=
(DESCRIPTION=
(ADDRESS=(PROTOCOL=tcp)(HOST=10.211.55.112)(PORT=1521))
(CONNECT_DATA=
(SERVICE_NAME=orcl)
)
)
)';
--通过dblink捞取数据
create table lucifer.lucifer_0618 as select /*+full(lucifer)*/ * from lucifer.lucifer@ORCL112;
select * from lucifer.lucifer_0618;

至此，整个RMAN恢复过程就结束了。

总之，有备份什么都好说。所以，作为DBA，备份一定要做好！！！