Database started and automatically going down because of PMON termination.

In the alert log:

PMON (ospid: 9776): terminating the instance due to error 472

Mon Jan 12 10:44:38 2015

Instance terminated by PMON, pid = 9776

Solution:

This error due to undo corruption in the database can be solved with creating undo tablespace and deleting old undo tablespace

Step1:Query Undo Parameters

SQL> show parameter undo

NAME                                 TYPE        VALUE

------------------------------------ ----------- --------

undo_management                      string      AUTO

undo_retention                       integer     900

undo_tablespace                      string      UNDOTBS1

Step2: Query for the undo tablespace name and location

SQL> select tablespace_name, file_name from dba_data_files

  2  where tablespace_name like '%UNDO%';

TABLESPACE FILE_NAME

---------- ----------------------------------------

UNDOTBS1    C:\ORACLE\ORADATA\MYDB1\UNDO_TBS01.DBF

Step3: Create New undo tablespace

create UNDO tablespace UNDOTBS DATAFILE 'C:\oracle\oradata\mydb1\UNDOTBS01.dbf' size 1615M REUSE AUTOEXTEND ON NEXT 4096k

Step4: Set undo tablespace parameter

SQL> alter system set undo_tablespace = 'UNDOTBS' scope=spfile;

Step5: Offline the old undo tablespace and drop

SQL> alter tablespace UNDOTBS1offline;

SQL> drop tablespace UNDOTBS1 including contents and datafiles;

Step6: Changed the undo management parameter to AUTO

SQL> alter system set undo_management='AUTO' scope=spfile;