-- Add reference columns so notifications can link to leave requests and pass slips.
-- These allow the app to store leave_id/pass_slip_id in notifications (and send to clients).

ALTER TABLE notifications
  ADD COLUMN IF NOT EXISTS leave_id uuid REFERENCES leave_of_absence(id) ON DELETE CASCADE;

ALTER TABLE notifications
  ADD COLUMN IF NOT EXISTS pass_slip_id uuid REFERENCES pass_slips(id) ON DELETE CASCADE;