I installed oracle 11g on ubuntu 11.10, but it seems that every couple of days I'll get to work and the database isn't running but the listener is.
To fix it, all I have to do is login and start it up:
su - oracle
cd /path/to/oracle11g/bin
./sqlplus sys as sysdba
startup;
exit
and then everything's ok. Taking a look at the alert log at: /u01/app/oracle/diag/rdbms/mydb/mydb/alert/log.xml
It looks like the problem started here:
<msg time='2012-03-09T22:00:02.570+01:00' org_id='oracle' comp_id='rdbms'
msg_id='kesaiTuneSqlDrv:4182:2579917519' client_id='' type='NOTIFICATION'
group='sqltune' level='16' module='DBMS_SCHEDULER'
pid='4460'>
<txt>Begin automatic SQL Tuning Advisor run for special tuning task "SYS_AUTO_SQL_TUNING_TASK"
</txt>
</msg>
<msg time='2012-03-09T22:00:31.273+01:00' org_id='oracle' comp_id='rdbms'
msg_id='3646992671' type='INCIDENT_ERROR' group='Generic Internal Error'
level='1' prob_key='ORA 600 [kgkprrpicknext1]' upstream_comp=''
downstream_comp='' ecid='' errid='11150'
detail_path='/u01/app/oracle/diag/rdbms/mydb/mydb/trace/mydb_ora_29268.trc'>
<txt>Errors in file /u01/app/oracle/diag/rdbms/mydb/mydb/trace/mydb_ora_29268.trc (incident=11150):
ORA-00600: internal error code, arguments: [kgkprrpicknext1], [18], [2], [], [], [], [], []
</txt>
</msg>