i := 0;
LOOP
    i := i + 100;
    MERGE  /*+LEADING(a) USE_NL(a) */
     INTO  nscreen.n_user_info nu
    USING  (
            SELECT /*+ LEADING(b) USE_NL(a) */
                   b.nu_user_id
                 , SUM(fi_size) sum_fi_size
              FROM n_file_tb a
                 , n_user_info b
             WHERE b.nu_user_id = a.fi_u_id
               AND b.nu_id BETWEEN i-99 AND i
               AND a.fi_status IN (1, 2)
             GROUP BY b.nu_user_id
            ) a
       ON  (a.nu_user_id = nu.nu_user_id)
     WHEN  MATCHED THEN
    UPDATE SET nu.nu_remainsize = a.sum_fi_size
    ;
    EXIT WHEN SQL%ROWCOUNT = 0;
END LOOP;