如何解决Ora-00600 4194错误

启动数据库出现Ora-00600 4194错误，观察alert文件，主要错误日志如下:

Sat Jan 21 13:55:21 2006
Errors in file /opt/oracle/admin/conner/bdump/conner_smon_17113.trc:
ORA-00600: internal error code, arguments: [4194], [43], [46], [], [], [], [], []
Sat Jan 21 13:55:21 2006
Errors in file /opt/oracle/admin/conner/udump/conner_ora_17121.trc:
ORA-00600: internal error code, arguments: [4194], [45], [44], [], [], [], [], [] 

4194错误通常说明UNDO段出现问题,最好的办法是通过备份进行恢复,如果没有备份,那么可以通过特殊的初始化参数进行强制启动,本文就Oracle的隐含参数进行恢复说明(由于实际情况可能各不相同，进行测试前请先行备份)，仅供参考。
首先确定当前回滚段名称，这可以从alert文件中获得:
Sat Jan 21 13:55:21 2006
Undo Segment 11 Onlined
Undo Segment 12 Onlined
Undo Segment 13 Onlined
Successfully onlined Undo Tablespace 16. 
对应的AUM (auto undo management) 下的回滚段名称为: 
'_SYSSMU11$','_SYSSMU12$','_SYSSMU13$'
 修改init<sid>.ora参数文件，使用Oracle隐含参数_corrupted_rollback_segments将回滚段标记为损坏，此时启动数据库，Oracle会跳过对于这些回滚段的相关操作，强制启动数据库。
._corrupted_rollback_segments='_SYSSMU11$','_SYSSMU12$','_SYSSMU13$'
使用init<sid>.ora参数文件启动数据库: 
[oracle@jumper dbs]$ sqlplus "/ as sysdba"
SQL*Plus: Release 9.2.0.4.0 - Production on Sat Jan 21 13:56:47 2006
Copyright (c) 1982, 2002, Oracle Corporation.  All rights reserved.
Connected to an idle instance.
SQL> startup pfile=initconner.ora
ORACLE instance started.
Total System Global Area   97588504 bytes
Fixed Size                   451864 bytes
Variable Size              33554432 bytes
Database Buffers           62914560 bytes
Redo Buffers                 667648 bytes
Database mounted.
Database opened. 
此时数据库正常Open。
观察alert文件可以获得如下信息: 
Sat Jan 21 13:57:03 2006
SMON: enabling tx recovery
SMON: about to recover undo segment 11
SMON: mark undo segment 11 as needs recovery
SMON: about to recover undo segment 12
SMON: mark undo segment 12 as needs recovery
SMON: about to recover undo segment 13
SMON: mark undo segment 13 as needs recovery
Sat Jan 21 13:57:03 2006
Database Characterset is ZHS16GBK
Sat Jan 21 13:57:03 2006
SMON: about to recover undo segment 11
SMON: mark undo segment 11 as needs recovery
SMON: about to recover undo segment 12
SMON: mark undo segment 12 as needs recovery
SMON: about to recover undo segment 13
SMON: mark undo segment 13 as needs recovery
Sat Jan 21 13:57:04 2006
Created Undo Segment _SYSSMU1$
Undo Segment 1 Onlined
Completed: ALTER DATABASE OPEN
aSat Jan 21 14:02:11 2006
SMON: about to recover undo segment 11
SMON: mark undo segment 11 as needs recovery
SMON: about to recover undo segment 12
SMON: mark undo segment 12 as needs recovery
SMON: about to recover undo segment 13
SMON: mark undo segment 13 as needs recovery 
此时可以重新创建新的UNDO表空间，删除出现问题的表空间，修改参数文件，由参数文件生成新的spfile，重新启动数据库： 
SQL> create undo tablespace undotbs1
  2  datafile '/opt/oracle/oradata/conner/undotbs1.dbf' size 10M;
Tablespace created.
SQL> alter system set undo_tablespace=undotbs1;
System altered.

SQL> drop tablespace undotbs2;
Tablespace dropped. 
此时的alert文件记录的: 
Sat Jan 21 14:03:29 2006
create undo tablespace undotbs1
datafile '/opt/oracle/oradata/conner/undotbs1.dbf' size 10M
Sat Jan 21 14:03:29 2006
Created Undo Segment _SYSSMU2$
Created Undo Segment _SYSSMU3$
Created Undo Segment _SYSSMU4$
Created Undo Segment _SYSSMU5$
Created Undo Segment _SYSSMU6$
Created Undo Segment _SYSSMU7$
Created Undo Segment _SYSSMU8$
Created Undo Segment _SYSSMU9$
Created Undo Segment _SYSSMU10$
Created Undo Segment _SYSSMU14$
Starting control autobackup
Control autobackup written to DISK device
        handle '/opt/oracle/product/9.2.0/dbs/c-3152029224-20060121-00'
Completed: create undo tablespace undotbs1
datafile '/opt/ora
Sat Jan 21 14:03:43 2006
Undo Segment 2 Onlined
Undo Segment 3 Onlined
Undo Segment 4 Onlined
Undo Segment 5 Onlined
Undo Segment 6 Onlined
Undo Segment 7 Onlined
Undo Segment 8 Onlined
Undo Segment 9 Onlined
Undo Segment 10 Onlined
Undo Segment 14 Onlined
Successfully onlined Undo Tablespace 1.
Undo Segment 1 Offlined
Undo Tablespace 16 successfully switched out.
Sat Jan 21 14:03:43 2006
ALTER SYSTEM SET undo_tablespace='UNDOTBS1' SCOPE=MEMORY;
Sat Jan 21 14:07:18 2006
SMON: about to recover undo segment 11
SMON: mark undo segment 11 as needs recovery
SMON: about to recover undo segment 12
SMON: mark undo segment 12 as needs recovery
SMON: about to recover undo segment 13
SMON: mark undo segment 13 as needs recovery
Sat Jan 21 14:08:06 2006
drop tablespace undotbs2
Sat Jan 21 14:08:07 2006
Starting control autobackup
Control autobackup written to DISK device
        handle '/opt/oracle/product/9.2.0/dbs/c-3152029224-20060121-01'
Completed: drop tablespace undotbs2 
修改参数文件，变更undo表空间，并取消_corrupted_rollback_segments设置: 
*.undo_tablespace='UNDOTBS1' 
由参数文件创建spfile文件。 
SQL> create spfile from pfile;
File created.
SQL> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.
SQL> startup
ORACLE instance started.
Total System Global Area   97588504 bytes
Fixed Size                   451864 bytes
Variable Size              33554432 bytes
Database Buffers           62914560 bytes
Redo Buffers                 667648 bytes
Database mounted.
Database opened. 
重起数据库，观察alert文件:
Sat Jan 21 14:08:36 2006
Undo Segment 2 Onlined
Undo Segment 3 Onlined
Undo Segment 4 Onlined
Undo Segment 5 Onlined
Undo Segment 6 Onlined
Undo Segment 7 Onlined
Undo Segment 8 Onlined
Undo Segment 9 Onlined
Undo Segment 10 Onlined
Undo Segment 14 Onlined
Successfully onlined Undo Tablespace 1. 
此时数据库恢复正常，通常建议立即全库exp，然后重新建库，再imp恢复数据库。