ORA-00600 and Severity Level

if you are a DBA, then you must have faced “ORA-00600” error. This is a generic error that potentially represent a defect and you will need to contact Oracle Support for help to fix the faced problem.

The error can be found in “alert.log” file , however there are different severity levels of ORA-600….. to find out you can use the very useful view: V$diag_alert_ext

The view has a column called “message_level”  that indicates the severity level as shown below:

1 : CRITICAL: critical errors

2 : SEVERE: severe errors

8 : IMPORTANT: important message

16 : NORMAL: normal message

In a production system you will need monitor and check if either severity “1” or “2” is being thrown in the alert log file. So, basically this useful view provides more detailed information about the error…. having ORA-600 with severity level “16” is normal message alert and can be ignored.

*** This query will catch ORA-600 with severity level 1

SQL> select originating_timestamp,detailed_location,message_level,message_text,problem_key from V$diag_alert_ext where message_level=1 and message_text like’%ORA-00600%’ order by originating_timestamp desc;











RMAN List Backup Summary command

one of the useful RMAN commands is:

RMAN> list backup summary;



so what are these columns represent ?

* LV column lists the following:

0 = incremental level 0 backup

1 = incremental level 1 backup

A = archivelogs

f = full – backup database command

* S is the status:

A = available

U = unavailable

As mentioned above F can represent either “FULL” backup or “Control File” Backup. If your RMAN configuration for controlfile auto-backup is set to “ON” , the control file backup will be taken automatically each time RMAN backup runs as shown in the above picture.

The RMAN configuration is:












ArcGIS 10.6.1 error after Oracle 18c upgrade

In ESRI ArcGIS Geodatabase environment its very important to maintain your product life-cycle support. ArcGIS 10.6.1 is compatible with Oracle 18c ….however when you upgrade both environments (ArcSDE & Oracle)  and attempt to connect through ArcGIS Desktop , the following error will be thrown:


DBMS error[Unkown errorNo extended error]


This is a known bug by ESRI, the solution is to apply the following patch on your ArcGIS Desktop software:




Oracle oraversion

Since Oracle 18c after you successfully apply the patches on the database binaries you will notice that when you invoke sqlplus after that…the version is immediately changed/reflected:

In 19c, after patching the database binaries sqlplus is referencing 19.4 version number


This is due to changes being reflected in a file called “oraversion” under $ORACLE_HOME/bin directory


For example:

$ORACLE_HOME/bin/oraversion -baseVersion


$ORACLE_HOME/bin/oraversion -compositeVersion