SQL report on a changed field

Good afternoon,

In an effort to help train our helpdesk about the correct way to escalate tickets we have added a custom field "Marked for Review" so that we can run a report and look at tickets that escalated in-correctly. However, in the event the technician later goes back and un-checks this field it doesn't show in the report.

So, what we are looking for is a SQL query report that checks to see if that value has ever been changed (UDF_CHAR23) so that if it ever does become unselected it will still show on the report that it had been set at some point in time.

Ideally we'd like to run this report weekly and monthly - any takers? (I apologize, I'm not so hot with the SQL scripting).

Thanks in advance for anyone's time!

Al