今天测试部门的人叫我过去，说是数据库当了，起不来了。
我过去看了看情况，做了如下操作
SQL> shutdown immediate
数据库已经关闭。
已经卸载数据库。
ORACLE 例程已经关闭。
SQL> startup
ORACLE 例程已经启动。
Total System Global Area 135338868 bytes
Fixed Size 453492 bytes
Variable Size 109051904 bytes
Database Buffers 25165824 bytes
Redo Buffers 667648 bytes
数据库装载完毕。
ORA-01092: ORACLE 例程终止。强行断开连接
表面上看不出问题，我查看alert_oracas.log文件
SYS auditing is disabled
Starting up ORACLE RDBMS Version: 9.2.0.1.0.
System parameters with non-default values:
processes = 150
timed_statistics = TRUE
shared_pool_size = 50331648
large_pool_size = 8388608
java_pool_size = 33554432
control_files = f:\oracle\oradata\oracas\CONTROL01.CTL, f:\oracle\oradata\oracas\CONTROL02.CTL, f:\oracle\oradata\oracas\CONTROL03.CTL
db_block_size = 8192
db_cache_size = 25165824
compatible = 9.2.0.0.0
db_file_multiblock_read_count= 16
fast_start_mttr_target = 300
undo_management = AUTO
undo_tablespace = UNDOSTB1
undo_retention = 10800
remote_login_passwordfile= EXCLUSIVE
db_domain =
instance_name = oracas
dispatchers = (PROTOCOL=TCP) (SERVICE=oracasXDB)
job_queue_processes = 10
hash_join_enabled = TRUE
background_dump_dest = f:\oracle\admin\oracas\bdump
user_dump_dest = f:\oracle\admin\oracas\udump
core_dump_dest = f:\oracle\admin\oracas\cdump
sort_area_size = 524288
db_name = oracas
open_cursors = 300
star_transformation_enabled= FALSE
query_rewrite_enabled = FALSE
pga_aggregate_target = 19922944
aq_tm_processes = 1
PMON started with pid=2
DBW0 started with pid=3
LGWR started with pid=4
CKPT started with pid=5
SMON started with pid=6
RECO started with pid=7
CJQ0 started with pid=8
QMN0 started with pid=9
Mon Apr 18 17:30:25 2005
starting up 1 shared server(s) ...
starting up 1 dispatcher(s) for network address '(ADDRESS=(PARTIAL=YES)(PROTOCOL=TCP))'...
Mon Apr 18 17:30:26 2005
ALTER DATABASE MOUNT
Mon Apr 18 17:30:30 2005
Successful mount of redo thread 1, with mount id 2424210674.
Mon Apr 18 17:30:30 2005
Database mounted in Exclusive Mode.
Completed: ALTER DATABASE MOUNT
Mon Apr 18 17:30:30 2005
ALTER DATABASE OPEN
Mon Apr 18 17:30:32 2005
Thread 1 opened at log sequence 105
Current log# 2 seq# 105 mem# 0: F:\ORACLE\ORADATA\ORACAS\REDO02.LOG
Successful open of redo thread 1.
Mon Apr 18 17:30:32 2005
SMON: enabling cache recovery
Mon Apr 18 17:30:34 2005
Errors in file f:\oracle\admin\oracas\udump\oracas_ora_3404.trc:
ORA-30012: 撤消表空间 'UNDOSTB1' 不存在或类型不正确
Mon Apr 18 17:30:34 2005
Error 30012 happened during db open, shutting down database
USER: terminating instance due to error 30012
Mon Apr 18 17:30:35 2005
Errors in file f:\oracle\admin\oracas\bdump\oracas_smon_996.trc:
ORA-30012: undo tablespace '' does not exist or of wrong type
Mon Apr 18 17:30:35 2005
Errors in file f:\oracle\admin\oracas\bdump\oracas_pmon_3500.trc:
ORA-30012: undo tablespace '' does not exist or of wrong type
Instance terminated by USER, pid = 3404
ORA-1092 signalled during: ALTER DATABASE OPEN...
于是我查看了以下信息来确认undo表空间的问题
SQL> conn sys/sys@oracas as sysdba
已连接到空闲例程。
SQL> startup mount
ORACLE 例程已经启动。
Total System Global Area 135338868 bytes
Fixed Size 453492 bytes
Variable Size 109051904 bytes
Database Buffers 25165824 bytes
Redo Buffers 667648 bytes
数据库装载完毕。
SQL> select name from v$datafile;
NAME
------------------------------------------------------------------------
F:\ORACLE\ORADATA\ORACAS\SYSTEM01.DBF
F:\ORACLE\ORADATA\ORACAS\UNDOTBS01.DBF
F:\ORACLE\ORADATA\ORACAS\CWMLITE01.DBF
F:\ORACLE\ORADATA\ORACAS\DRSYS01.DBF
F:\ORACLE\ORADATA\ORACAS\EXAMPLE01.DBF
F:\ORACLE\ORADATA\ORACAS\INDX01.DBF
F:\ORACLE\ORADATA\ORACAS\ODM01.DBF
F:\ORACLE\ORADATA\ORACAS\TOOLS01.DBF
F:\ORACLE\ORADATA\ORACAS\USERS01.DBF
F:\ORACLE\ORADATA\ORACAS\XDB01.DBF
D:\ORADATA\ORACAS\TSCAS11.DBF
E:\ORADATA\ORACAS\TFCAS12.DBF
D:\ORADATA\ORACAS\TSCAS21.DBF
E:\ORADATA\ORACAS\TFCAS22.DBF
D:\ORADATA\ORACAS\TSCAS31.DBF
E:\ORADATA\ORACAS\TFCAS32.DBF
D:\ORADATA\ORACAS\TSCAS41.DBF
E:\ORADATA\ORACAS\TFCAS42.DBF
D:\ORADATA\ORACAS\TSCASINDX1.DBF
E:\ORADATA\ORACAS\TSCASINDX2.DBF
D:\ORADATA\ORACAS\TFCAS13.DBF
D:\ORADATA\ORACAS\TFCAS14.DBF
D:\ORADATA\ORACAS\TFCAS23.DBF
D:\ORADATA\ORACAS\TFCAS24.DBF
E:\ORADATA\ORACAS\TSCASINDX12.DBF
E:\ORADATA\ORACAS\TSCASINDX13.DBF
E:\ORADATA\ORACAS\TSCASINDX24.DBF
E:\ORADATA\ORACAS\TSCASINDX25.DBF
C:\SNAPSHOT01.DBF
C:\TSCAS1.DBF
已选择30行。
SQL> show parameter undo
NAME TYPE VALUE
------------------------------------ ----------- -----------------------
undo_management string AUTO
undo_retention integer 10800
undo_suppress_errors boolean FALSE
undo_tablespace string UNDOSTB1
SQL> select name from v$tablespace;
NAME
------------------------------
CWMLITE
DRSYS
EXAMPLE
INDX
ODM
SYSTEM
TOOLS
UNDOTBS1
USERS
XDB
TEMP
TSCAS1
TSCAS2
TSCAS3
TSCAS4
TSCASINDX1
TSCASINDX2
SNAPSHOT_TS
已选择18行。
当时没有自己看问题，就以为是undo文件损坏了，决定重建。
注意：后来才发现这里以后的操作是饶了一个解决问题的弯路。
由于不open没有办法重新创建undo 表空间，所以决定先用系统默认的undo表空间来启动，然后重建undo
表空间，具体操作如下：
SQL> create pfile from spfile;
文件已创建。
修改pfile文件
#.undo_management='AUTO'
#.undo_tablespace='UNDOSTB1'
undo_management=manual
undo_tablespace='system'
关闭数据库，并且从目录F:\oracle\ora92\database下去掉SPFILEORACAS.ORA文件
重新启动
SQL> shutdown immediate
ORA-01109: 数据库未打开
已经卸载数据库。
ORACLE 例程已经关闭。
SQL> startup mount
ORACLE 例程已经启动。
Total System Global Area 135338868 bytes
Fixed Size 453492 bytes
Variable Size 109051904 bytes
Database Buffers 25165824 bytes
Redo Buffers 667648 bytes
数据库装载完毕。
SQL> alter database open;
数据库已更改。
查看表空间信息
SQL> show parameter undo
NAME TYPE VALUE
------------------------------------ ----------- ------------------------------
undo_management string MANUAL
undo_retention integer 10800
undo_suppress_errors boolean FALSE
undo_tablespace string system
SQL> select name from v$tablespace;
NAME
------------------------------
CWMLITE
DRSYS
EXAMPLE
INDX
ODM
SYSTEM
TOOLS
UNDOTBS1
USERS
XDB
TEMP
TSCAS1
TSCAS2
TSCAS3
TSCAS4
TSCASINDX1
TSCASINDX2
SNAPSHOT_TS