DB issue: Business modeler/Engine Admin cannt connect to database

Problem: When trying to open Demantra Business modeler on my local install, started getting error "ORA-01033 ORACLE initialization or shutdown in progress ". Also found that while connecting to Engine Administrator I started getting error "Cann't connect to database".

Analysis: Found that even while tnsping to database works, even SQLplus connection to database using Oralce SQLPLUS wouldn't work. It happens at times when the last DB shutdown didnt happen properly. Database needs to be re-started after shutting down explicitly by using SQL PLUS.

Solution:

Using command prompt,

Login as:
> sqlplus /nolog

Once logged in, use following commands:

SQL> connect / as sysdba
ConnectÚ.
SQL> shutdown abort
Instance ORACLE arrÛtÚe.
SQL> startup nomount
Instance ORACLE lancÚe.

While executing this, I got below error:

Database mounted.

ORA-00600: internal error code, arguments: [kcratr1_lastbwr], [], [], [], [],[], [], []

To further fix this issue, used following commands to re-start database:

SQL> startup mount
ORACLE instance started.

Total System Global Area 1073741824 bytes
Fixed Size 1264916 bytes
Variable Size 264241900 bytes
Database Buffers 801112064 bytes
Redo Buffers 7122944 bytes
Database mounted.
SQL> recover database
Media recovery complete.
SQL> alter database open;

Database altered.

Verify that you are able to login into Database and then into Demantra applications. All set and we are back to action.