Oracle 10g数据库闪回之后怎么样noresetlogs打开数据库(一)
很多时候数据库resetlogs打开之后会引起诸多不便，比如在Oracle 10g下，闪回数据库之后必须要resetlogs打开，那怎么样才能避免数据库resetlogs打开呢？
以下步骤仅用于测试，在生产环境下慎用。
（1）将数据库启动在mount状态，打开强制模式的闪回点dd，记录控制文件的checkpoint和checkpoint count
SQL> startup mount
ORACLE instance started.

Total System Global Area 1069547520 bytes
Fixed Size                  2101704 bytes
Variable Size             276827704 bytes
Database Buffers          784334848 bytes
Redo Buffers                6283264 bytes
Database mounted.

SQL>  create restore point dd guarantee flashback database;

Restore point created.

SQL> select to_char(checkpoint_change#) from v$datafile;

TO_CHAR(CHECKPOINT_CHANGE#)
----------------------------------------
10999733115905
10999733115905
10999733115905
10999733115905


SQL> select file#,to_char(checkpoint_change#),CHECKPOINT_COUNT from v$datafile_header;

     FILE# TO_CHAR(CHECKPOINT_CHANGE#)              CHECKPOINT_COUNT
---------- ---------------------------------------- ----------------
         1 10999733115905                                         70
         2 10999733115905                                         70
         3 10999733115905                                         70
         4 10999733115905                                         69

（2）在mount状态下备份控制文件和日志文件
[ora10g@xe2 lank]$ cp redo01.log redo01.log.bak     
[ora10g@xe2 lank]$ cp redo02.log redo02.log.bak     
[ora10g@xe2 lank]$ cp redo03.log redo03.log.bak         
[ora10g@xe2 lank]$ cp control01.ctl control01.ctl.bak

（3）打开数据库之后切换几个归档
SQL> alter database open;

Database altered.

SQL> alter system switch logfile;

System altered.

SQL> /

System altered.

SQL> /

System altered.


（4）将数据库闪回至闪回点dd，可以发现数据文件的checkpoint和控制文件checkpoint均已闪回至闪回点状态，但是checkpoint count没有，这需要用bbed手动修改
SQL> flashback database to restore point dd;

Flashback complete.

SQL> select to_char(checkpoint_change#) from v$datafile_header;

TO_CHAR(CHECKPOINT_CHANGE#)
----------------------------------------
10999733115905
10999733115905
10999733115905
10999733115905

SQL>  select file#,to_char(checkpoint_change#),CHECKPOINT_COUNT from v$datafile_header;

     FILE# TO_CH