allow resetlogs corruption

my production database hang. when the OS restart the oracle datafile of the redo

file broken. i try to alter database open resetlogs, but the database's datafiles are not consistent. Unfortunatly, this database do not backup completely recently.

 

Solution

1)_ALLOW_RESETLOGS_CORRUPTION = TRUE

Adding this parameter in pfile and startup with it. this prameter force database to open

without current online redolog and datafiles are inconsistent.

2)recover database

alter database openresetlogs;
after doing this operation, i can get the ORA- error in alert file.
==================
ORA-00600: internal error code, arguments: [2256], [0], [3221225472], [5], [3880116460], [],

[], []
==================
the fourth parameter [5] shows that what level we should rollback.

sqlplus "/ as sysdba"
alter session set events '10015 trace name adjust_scn level 24';

level 24 is computed by the fourth parameter from the ORA-00600 error.
(5+1)*4=24

Remark: level 1 will rollback 1 billion （ 1024 * 1024 * 1024 ）SCN.
we can query this parameter from this view.
select KSPPDESC from X$KSPPI where ksppinm='_allow_resetlogs_corruption';

Reference:
http://www.cnblogs.com/yifan268/archive/2008/10/08/1306520.html