Tag: tunning advisor

Hi all,

So I got to receive frequently this error, always on same hour, from a database:

ORA-00600: internal error code, arguments: [qksvcReplaceVC0], [], [], [], [], [], [], [], [], [], [], []

Not much was required for matching it to the Automatic SQL Tuning Advisor.

This only seems to happen during execution of Automatic SQL Tuning Advisor. Several bugs have been logged for the issue but have not been resolved as the error is not reproducible at will. For example:

Bug 17401718: ORA-600 [QKSVCREPLACEVC0] USING SQL TUNING ADVISOR
Bug 16491690: ORA-600 [QKSVCREPLACEVC0] WHEN AUTOMATIC SQL TUNING ADVISOR EXECUTED
Bug 13959984: ORA-00600 [QKSVCREPLACEVC0]

How to fix it? Apply the patches!

To workaround it?

A few options:

1. Setting “_replace_virtual_columns” to false.

You can set this parameter at both session (where automatic SQL Tuning Advisor starts)
and system level with the following commands-

SQL> alter session set "_replace_virtual_columns"=false;

SQL> alter system set "_replace_virtual_columns"=false

2. Since it is only failing in the SQL Tuning Advisor auto task and has no effect on the database the error can be ignored.
You can disable that auto task and just run it manually when required:

–check auto job status

SQL> select client_name,status from dba_autotask_task;

SQL> select client_name,status from dba_autotask_client;

SQL> select client_name, operation_name, status from dba_autotask_operation;

–disable SQL Tuning Advisor job

SQL> exec dbms_auto_task_admin.disable ('sql tuning advisor', null, null);

-OR-

SQL> exec dbms_auto_task_admin.disable (client_name => 'sql tuning advisor', operation => null, window_name => null);

–enable SQL Tuning Advisor job

SQL> exec dbms_auto_task_admin.enable ('sql tuning advisor', null, null);

-OR-

SQL> exec dbms_auto_task_admin.enable (client_name => 'sql tuning advisor', operation => null, window_name => null);

 

Hope it helps!