I have an employees table and one column in the employees table is "supervisor_id" which is an FK to the id column. I have employees from numerous companies all in the same table. I have a column called company_id that indicates the company. I want to make sure that an employee chooses a supervisor from the same company. I have a column called company_ID. How do I make sure that the employee company ID matches the supervisor's company ID? Do I need to use a trigger or is there a way I can do this with foreign keys? TIA Matt
