Learn how to add and remove Primary Keys from an Access database table. The primary key's purpose is to promptly associate data from multiple tables and combine that data.

I do not believe Jet (the database engine Access uses) supports table-level triggers, so you'll need to use a macro or VBA code in a form to trigger the extra record.

In Microsoft Access, fields can be added and removed from the list of available fields. Learn how to add or delete a Field in Design View in Access.