SELECT r.type, r.request_from, r.request_to, d.departure_date
    FROM requests as r
    JOIN d_requests as d ON r.request_id = d.requests_id
    WHERE r.type='d' AND r.request_from='Beijing'
    AND r.request_to='Tokyo' AND d.departure_date
          IN (SELECT s.s_before from s_requests s where s.s_before<='user_defined_date')
    ORDER BY d.departure_date