实验环境：red hat 5.8
oracle环境：11.2.0.3
实验情况：新建的表空间，来不及备份，就已经损坏的情况下。
新建的表空间，没有备份，无法转储，只能重建数据文件
1、查看一下现有的数据文件位置。
sys@TEST0910> select file#,name from v$datafile;
FILE# NAME
---------- --------------------------------------------------
1 /u01/app/oracle/oradata/test0910/system01.dbf
2 /u01/app/oracle/oradata/test0910/sysaux01.dbf
3 /u01/app/oracle/oradata/test0910/undotbs01.dbf
4 /u01/app/oracle/oradata/test0910/users01.dbf
5 /u01/app/oracle/oradata/test0910/example01.dbf
6 /u01/app/oracle/oradata/test0910/testtb.dbf
6 rows selected.
2、新建一个表空间和一个数据表。
sys@TEST0910> create tablespace lxtbs datafile '/u01/app/oracle/oradata/test0910/lxtb01.dbf' size 20m;
Tablespace created.
在新建的表空间中新建一个表。
sys@TEST0910> create table scott.lxtb tablespace lxtbs as select * from scott.emp;
Table created.
3、插入三次数据，分别为提交归档，提交不归档，不提交不归档。
1.提交归档
sys@TEST0910> insert into scott.lxtb select * from scott.emp;
14 rows created.
sys@TEST0910> commit;
Commit complete.
sys@TEST0910> alter system archive log current;
System altered.
sys@TEST0910> select count(*) from scott.lxtb;
COUNT(*)
----------
28
2.提交不归档
sys@TEST0910> insert into scott.lxtb select * from scott.emp;
14 rows created.
sys@TEST0910> commit;
Commit complete.
sys@TEST0910> select count(*) from scott.lxtb;
COUNT(*)
----------
42
3.不提交，不归档
sys@TEST0910> insert into scott.lxtb select * from scott.emp;
14 rows created.
sys@TEST0910> select count(*) from scott.lxtb;
COUNT(*)
----------
56
4、模拟断电。
sys@TEST0910> shutdown abort;
ORACLE instance shut down.
5、删除新建的表空间上的数据文件
[oracle@rtest ~]$ rm /u01/app/oracle/oradata/test0910/lxtb01.dbf
[oracle@rtest ~]$ ls /u01/app/oracle/oradata/test0910/lxtb01.dbf
ls: /u01/app/oracle/oradata/test0910/lxtb01.dbf: No such file or directory
6、起库，报错，查询损坏的数据文件
sys@TEST0910> startup
ORACLE instance started.
Total System Global Area 2505338880 bytes
Fixed Size 2230952 bytes
Variable Size 587203928 bytes
Database Buffers 1895825408 bytes
Redo Buffers 20078592 bytes
Database mounted.
ORA-01157: cannot identify/lock data file 7 - see DBWR trace file
ORA-01110: data file 7: '/u01/app/oracle/oradata/test0910/lxtb01.dbf'
查询哪个是坏的，这个数据文件没有备份。
sys@TEST0910> select file#,error from v$recover_file;
FILE# ERROR
---------- -----------------------------------------------------------------
7 FILE NOT FOUND
7、可先使用高可用模式先开库
sys@TEST0910> alter database datafile 7 offline;
Database altered.
sys@TEST0910> alter database open;
Database altered.
8、利用日志文件来恢复数据文件
新建一个空白的文件，用日志来恢复。这个就相当于转储。
sys@TEST0910> alter database create datafile '/u01/app/oracle/oradata/test0910/lxtb01.dbf';
Database altered.
sys@TEST0910> alter database datafile 7 online;
Database altered.
sys@TEST0910> select count(*) from scott.lxtb;
COUNT(*)
----------
42
http://blog.csdn.net/rlhua/article/details/11869935
