MERGE INTO table_master m
USING (SELECT id
            , str_cd
            , slip_no
            , SUM(tot_qty) AS tot_qty
            , SUM(tot_amt) AS tot_amt
            , sysdate      AS reg_date
         FROM table_detail
        WHERE slip_no = vSlip_no
          AND str_cd  = vStr_cd
          AND id      = vId
        GROUP BY id, str_cd, slip_no
       ) d
   ON (m.slip_no = d.slip_no AND
       m.str_cd  = d.str_cd  AND
       m.id      = d.id      )
 WHEN MATCHED THEN
      UPDATE SET m.tot_qty  = d.tot_qty
               , m.tot_amt  = d.tot_amt
               , m.reg_date = d.reg_date
 WHEN NOT MATCHED THEN
      INSERT (  id,   str_cd,   slip_no,   tot_qty,   tot_amt,   reg_date)
      VALUES (d.id, d.str_cd, d.slip_no, d.tot_qty, d.tot_amt, d.reg_date)
;