当数据库出现了hang的情况，如何收集数据？

可以通过 sqlplus -prelim / as sysdba进入数据库，然后通过ORADEBUG hanganalyze收集一些数据。收起

楼上正解
还可以看看 http://www.dba-oracle.com/t_conn ... g_prelim_option.htm

年初正好碰巧用过一次prelim，这是当时的情况（虽然不是hang situation）:

$ sqlplus / as sysdba
SQL*Plus: Release 11.2.0.3.0 Production on Mon Jan 5 12:33:40 2015
Copyright (c) 1982, 2011, Oracle.  All rights reserved.
ERROR:
ORA-00020: maximum number of processes (450) exceeded

$ sqlplus -prelim / as sysdba
SQL*Plus: Release 11.2.0.3.0 Production on Mon Jan 5 12:38:28 2015
Copyright (c) 1982, 2011, Oracle.  All rights reserved.
SQL> shutdown abort
ORACLE instance shut down.收起