SELECT contacts.grade, contacts.grade_entrance_date, contacts_g201606.grade, contacts_g201606.grade_entrance_date FROM contacts, contacts_g201606 WHERE contacts.id=contacts_g201606.id

UPDATE contacts, contacts_g201606 SET contacts_g201606.grade_old=contacts.grade, contacts_g201606.grade_entrance_date_old=contacts.grade_entrance_date WHERE contacts.id=contacts_g201606.id

UPDATE contacts, contacts_g201606 SET contacts.grade=contacts_g201606.grade, contacts.grade_entrance_date=contacts_g201606.grade_entrance_date WHERE contacts.id=contacts_g201606.id