datafile恢复问题

飞飞 · 发表于 2010-10-26 06:21:36

小菜我练习书上的实验
出错了，信息如下
SQL> select file#,name from v$datafile;
   FILE# NAME
---------- --------------------------------------------------
      1 /u01/app/oracle/oradata/ora10g/system01.dbf
      2 /u01/app/oracle/oradata/ora10g/undotbs01.dbf
      3 /u01/app/oracle/oradata/ora10g/sysaux01.dbf
      4 /u01/app/oracle/oradata/ora10g/users01.dbf
      5 /u01/app/oracle/oradata/ora10g/example01.dbf
      6 /u01/app/oracle/oradata/ora10g/app01_01.dbf
      7 /u01/app/oracle/oradata/ora10g/ntest.dbf
      8 /u01/app/oracle/oradata/ora10g/app1_01.dbf
8 rows selected.
SQL> alter database datafile 7 offline;
Database altered.
SQL> alter database create datafile '/u01/app/oracle/oradata/ora10g/ntest.dbf';
alter database create datafile '/u01/app/oracle/oradata/ora10g/ntest.dbf'
*
ERROR at line 1:
ORA-01178: file 7 created before last CREATE CONTROLFILE, cannot recreate
ORA-01110: data file 7: '/u01/app/oracle/oradata/ora10g/ntest.dbf'
实验做的是删除 datafile:
/u01/app/oracle/oradata/ora10g/ntest.dbf
然后做恢复
做恢复要先offline，然后再重新创建datafile，可是重新创建datafile时，出现上面的错误。
是什么原因。
BTW，假设我新建tablespace和datafile做这个实验室成功的，不会报上面的错。