Enable or Disable Bug Fixes

The hidden parameter _FIX_CONTROL can be used to enable or disable certain bug fixes. This is often done to perform testcases or simulate scenarios and see how can affect a bug.

It is configured for a single hotfix as show below (at session level or system level). in this case (3426050) disable cartesian join on complex views, this is a very useful to reduce the use of cross join;

 

ALTER SESSION SET “_fix_control”=’3426050:OFF’;

 

It is configured for multiple hotfix as show below. In this case we include 6399597, disallow HASH GROUP BY for subquery processing and the 3426050;

 

ALTER SYSTEM SET “_fix_control”= ‘3426050:ON’, ‘6399597:ON’….  scope=spfile sid=’*’;

 

A full list of bug numbers which are controlled by fix control and theirs status can be found in the V$ views;

 

  • V$SYSTEM_FIX_CONTROL
  • V$SESSION_FIX_CONTROL

 

Because it is a hidden parameter, use of _fix_control must be authorized by MOS. In databases that we all have to make our experiments you can use it without problems.

HTH – Antonio NAVARRO

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s