查看oracle 数据库的DBID

（1）使用rman查看
$ rman target /
Recovery Manager: Release 11.2.0.4.0 - Production on Fri Jun 12 03:20:19 2015
Copyright (c) 1982, 2011, Oracle and/or its affiliates. All rights reserved.
connected to target database: DBTEST (DBID=1275017193)
RMAN>

（2）使用sqlplus查看
SQL> select dbid from v$database;

DBID
----------
1275017193

（3）dump文件查看

#dump日志文件
SQL> alter system dump logfile '/u01/app/oracle/oradata/dbtest/redo01.log';

#dump数据文件

SQL> alter system dump datafile '/u01/app/oracle/oradata/dbtest/users01.dbf' block min 1 block max 4;

#dump归档日志
SQL> alter system dump logfile '/home/oracle/arch/1_11_882154347.dbf';

然后查看dump文件的内容