一、冷备份
数据库在关闭状态下完成所有物理系统文件拷贝的过程,也称脱机备份
适合于非归档模式下,数据库处于一致性状态
二、步骤
首先在运行的库中得到数据库运行的所有的物理文件位置,然后在计划内关闭数据库(shutdown)
再执行拷贝物理文家到备份路径或备份设备
备份完成后立即启动数据库让其提供正常的服务
三、冷备脚本的写法
首先应该在相关视图里查出数据库的数据文件,日志文件,控制文件,临时文件所在的位置
注意:不要直接把oradata下的cp就行了,因为生产库里各个文件通常分布在不同的磁盘,不同的地方,所以在去视图里获得真实路径
--查看实例和数据库的相关信息
SQL>selectinstance_name,version,status,archiver,database_statusfromv$instance;
INSTANCE_NAMEVERSIONSTATUSARCHIVE DATABASE_STATUS
---------------- ----------------- ------------ ------- -----------------
orcl10.2.0.1.0OPENSTOPPED ACTIVE
SQL>selectdbid,name,log_modefromv$database;
DBIDNAMELOG_MODE
---------- --------- ------------
1242732291 ORCLNOARCHIVELOG
--查看数据文件及状态信息
SQL>selectfile_name,tablespace_name,status,online_statusfromdba_data_files;
FILE_NAMETABLESPACE STATUSONLINE_
------------------------------------------------------- ---------- --------- -------
/u01/app/oracle/oradata/orcl/undotbs01.dbfUNDOTBS1AVAILABLE ONLINE
/u01/app/oracle/oradata/orcl/system01.dbfSYSTEMAVAILABLE SYSTEM
/u01/app/oracle/oradata/orcl/sysaux01.dbfSYSAUXAVAILABLE ONLINE
/u01/app/oracle/oradata/orcl/users01.dbfUSERSAVAILABLE ONLINE
/u01/app/oracle/oradata/orcl/example01.dbfEXAMPLEAVAILABLE ONLINE
/u01/app/oracle/oradata/orcl/tbs1_1.dbfTBS1AVAILABLE ONLINE
/u01/app/oracle/oradata/orcl/tbs1_2.dbfTBS1AVAILABLE ONLINE
--查看数据文件
SQL>selectnamefromv$datafile;
NAME
--------------------------------------------------------------------------------
/u01/app/oracle/oradata/orcl/system01.dbf
/u01/app/oracle/oradata/orcl/undotbs01.dbf
/u01/app/oracle/oradata/orcl/sysaux01.dbf
/u01/app/oracle/oradata/orcl/users01.dbf
/u01/app/oracle/oradata/orcl/example01.dbf
/u01/app/oracle/oradata/orcl/tbs1_1.dbf
/u01/app/oracle/oradata/orcl/tbs1_2.dbf
--查看临时文件
SQL>selectnamefromv$tempfile;
NAME
--------------------------------------------------------------------------------
/u01/app/oracle/oradata/orcl/temp01.dbf
--查看日志文件
SQL>selectmemberfromv$logfile;
MEMBER
------------------------------------------------------------
/u01/app/oracle/oradata/orcl/redo2a.rdo
/u01/app/oracle/oradata/orcl/redo2b.rdo
/u01/app/oracle/oradata/orcl/redo1a.rdo
/u01/app/oracle/oradata/orcl/redo3a.rdo
/u01/app/oracle/oradata/orcl/redo3b.rdo
/u01/app/oracle/oradata/orcl/redo1b.rdo
--查看控制文件
SQL>selectnamefromv$controlfile;
NAME
------------------------------------------------------------
/u01/app/oracle/oradata/orcl/control01.ctl
/u01/app/oracle/oradata/orcl/control02.ctl
--创建备份目录
SQL>ho mkdir/u01/app/oracle/coolbak
--使用连接符生成复制文件命令
SQL>select'ho cp '||name||' /u01/app/oracle/coolbak'fromv$controlfile;
'HOCP'||NAME||'/U01/APP/ORACLE/COOLBAK'
----------------------------------------------------------------------------------
ho cp/u01/app/oracle/oradata/orcl/control01.ctl/u01/app/oracle/coolbak
ho cp/u01/app/oracle/oradata/orcl/control02.ctl/u01/app/oracle/coolbak
SQL>save/tmp/tmpbak.sql;--将上面的输入保存为tmpbak.sql
Createdfile/tmp/tmpbak.sql
SQL>ho vim/tmp/tmpbak.sql--编辑tmpbak.sql,将下面的内容输入到tmpbak.sql
setfeedbackoff
setheadingoff
setverifyoff
settrimspooloff
setpagesize 0
setlinesize 200
define dir='/u01/app/oracle/coolbak'
define script='/tmp/coolbak.sql'
spool&script
select'ho cp '||name||' &dir'fromv$controlfile
unionall
select'ho cp '||name||' &dir'fromv$datafile
unionall
select'ho cp '||member||' &dir'fromv$logfile
unionall
select'ho cp '||name||' &dir'fromv$tempfile
/
createpfile='&dir/initorcl.ora'fromspfile;
ho cp/u01/app/oracle/10g/dbs/orapworcl&dir
spooloff
shutdownimmediate
start&script
ho rm&script
startup
--执行tmpbak.sql
SQL>@/tmp/tmpbak.sql;
--执行过程及数据库启动略
--启动后查看备份的文件
SQL>ho ls/u01/app/oracle/coolbak
control01.ctlorapworclredo2b.rdosystem01.dbfusers01.dbf
control02.ctlredo1a.rdoredo3a.rdotbs1_1.dbf
example01.dbfredo1b.rdoredo3b.rdotbs1_2.dbf
initorcl.oraredo2a.rdosysaux01.dbfundotbs01.dbf
四、总结
优点
冷备模式下概念易于理解,即将需要备份的文件复制到安全的位置
操作比较简单,不需要太多的干预
容易恢复到某个时间点上(只需将文件再拷贝回去)
能与归档方法相结合,作数据库“最新状态”的恢复。
缺点
备份时,数据库必须处于一致性关闭状态
只能提供到某一时间点的恢复
备份时速度比较慢,尤其是数据量大性能影响比较大
不能实现基于表和用户级别的数据恢复