PROCEDURE monthly1( bgtime_arg DATE, endtime_arg DATE ) AS
   CURSOR c_pdno IS
      SELECT pdno FROM epdno;

   CURSOR c_input IS
      SELECT pdno, SUM(finum)
      FROM oltstate
      WHERE fidate >= bgtime_arg AND fidate < endtime_arg AND UPPER(state) = 'P'

      GROUP BY pdno


      ORDER BY pdno;

   CURSOR c_inputinv IS
      SELECT pdno, SUM(wfnum)
      FROM oltinv
      WHERE outtime >= bgtime_arg AND outtime < endtime_arg
      GROUP BY pdno
      ORDER BY pdno;

   CURSOR c_output IS
      SELECT pdno, SUM(fonum)


      FROM oltstate
      WHERE outpdate >= bgtime_arg AND outpdate < endtime_arg
      GROUP BY pdno
      ORDER BY pdno;

   CURSOR c_outputinv IS
      SELECT pdno, SUM(wfnum)
      FROM oltinv
      WHERE intime >= bgtime_arg AND intime < endtime_arg
      GROUP BY pdno
      ORDER BY pdno;


   CURSOR c_scrapfab IS
      SELECT pdno, SUM(bknwfs)
      FROM obknwfs
      WHERE thisday >= bgtime_arg AND thisday < endtime_arg
      GROUP BY pdno
      ORDER BY pdno;

   CURSOR c_wip IS
      SELECT pdno, SUM(wfnum)
      FROM oltno


      GROUP BY pdno
      ORDER BY pdno;

   CURSOR c_leadtime IS
      SELECT pdno, MIN(CEIL(fodate-fidate)) || ' - ' || MAX(CEIL(fodat
e-fidate))

      FROM oltstate
      WHERE outpdate >= bgtime_arg AND outpdate < endtime_arg
      GROUP BY pdno
      ORDER BY pdno;



   v_pdno         omonthlyreport1.pdno%TYPE;
   n_wafers       NUMBER;
   v_leadtime     omonthlyreport1.leadtime%TYPE;
   v_month        omonthlyreport1.thismonth%TYPE;
   n_workdays     NUMBER;
   n_outsum       NUMBER;
   n_scrapsum     NUMBER;
   [color=skyblue][color=skyblue][color=red]v_workmonth    oworkdays.thismonth%TYPE;[/color][/color][/color]
BEGIN
   v_month := TO_CHAR( bgtime_arg, 'YYYY MON' );


  [color=red] v_workmonth := TO_CHAR( bgtime_arg, 'MON');[/color]
   OPEN c_pdno;
   LOOP
      FETCH c_pdno INTO v_pdno;
      EXIT WHEN c_pdno%NOTFOUND;
      INSERT INTO omonthlyreport1(thismonth, pdno)
         VALUES(v_month,v_pdno);
   END LOOP;
   CLOSE c_pdno;



   OPEN c_input;
   LOOP
      FETCH c_input INTO v_pdno, n_wafers;
      EXIT WHEN c_input%NOTFOUND;
      UPDATE omonthlyreport1
         SET input = n_wafers
         WHERE UPPER(pdno) = UPPER(v_pdno) AND thismonth=v_month;
   END LOOP;
   CLOSE c_input;

   OPEN c_inputinv;


   LOOP
      FETCH c_inputinv INTO v_pdno, n_wafers;
      EXIT WHEN c_inputinv%NOTFOUND;
      UPDATE omonthlyreport1
         SET inputinv = n_wafers
         WHERE UPPER(pdno) = UPPER(v_pdno) AND thismonth=v_month;
   END LOOP;
   CLOSE c_inputinv;

   OPEN c_output;
   LOOP


      FETCH c_output INTO v_pdno, n_wafers;
      EXIT WHEN c_output%NOTFOUND;
      UPDATE omonthlyreport1
         SET output = n_wafers
         WHERE UPPER(pdno) = UPPER(v_pdno) AND thismonth=v_month;
      UPDATE oplan
         SET lastout = n_wafers, lastplan = thisplan, thisplan = NULL
         WHERE UPPER(pdno) = UPPER(v_pdno);
   END LOOP;
   CLOSE c_output;



   OPEN c_outputinv;
   LOOP
      FETCH c_outputinv INTO v_pdno, n_wafers;
      EXIT WHEN c_outputinv%NOTFOUND;
      UPDATE omonthlyreport1
         SET outputinv = n_wafers
         WHERE UPPER(pdno) = UPPER(v_pdno) AND thismonth=v_month;
   END LOOP;
   CLOSE c_outputinv;

   OPEN c_scrapfab;


   LOOP
      FETCH c_scrapfab INTO v_pdno, n_wafers;
      EXIT WHEN c_scrapfab%NOTFOUND;
      UPDATE omonthlyreport1
         SET scrapfab = n_wafers
         WHERE UPPER(pdno) = UPPER(v_pdno) AND thismonth=v_month;
   END LOOP;
   CLOSE c_scrapfab;

   OPEN c_wip;
   LOOP


      FETCH c_wip INTO v_pdno, n_wafers;
      EXIT WHEN c_wip%NOTFOUND;
      UPDATE omonthlyreport1
         SET wip = n_wafers
         WHERE UPPER(pdno) = UPPER(v_pdno) AND thismonth=v_month;
   END LOOP;
   CLOSE c_wip;

   OPEN c_leadtime;
   LOOP
      FETCH c_leadtime INTO v_pdno, v_leadtime;


      EXIT WHEN c_leadtime%NOTFOUND;
      UPDATE omonthlyreport1
         SET leadtime = v_leadtime
         WHERE UPPER(pdno) = UPPER(v_pdno) AND thismonth=v_month;
   END LOOP;
   CLOSE c_leadtime;



   INSERT INTO omonthlyreport1(thismonth, pdno)
      VALUES(v_month, 'zz1_total');


   SELECT MIN(CEIL(fodate-fidate)) || ' - ' || MAX(CEIL(fodate-fidate))

      INTO v_leadtime
      FROM oltstate
      WHERE outpdate >= bgtime_arg AND outpdate < endtime_arg;
   UPDATE omonthlyreport1
      SET ( input, inputinv, output, outputinv, scrapfab, scraptest, wip)

              = ( SELECT SUM(input), SUM(inputinv), SUM(output), SUM(outputinv),

                         SUM(scrapfab), SUM(scraptest), SUM(wip)
                  FROM omonthlyreport1
                    WHERE thismonth=v_month ),
          leadtime = v_leadtime
      WHERE thismonth=v_month AND pdno='zz1_total';

   SELECT NVL(output,0) + NVL(outputinv,0) + NVL(scrapfab,0) + NVL(scraptest,0),

          NVL(scrapfab,0) + NVL(scraptest,0)
      INTO n_outsum, n_scrapsum
      FROM omonthlyreport1
      WHERE thismonth=v_month AND pdno='zz1_total';
   INSERT INTO omonthlyreport1(thismonth, pdno, scrapfab)
      VALUES(v_month, 'zz2_scrapsum', n_scrapsum);

   INSERT INTO omonthlyreport1(thismonth, pdno)

      VALUES(v_month, 'zz3_average');
[color=red]   SELECT workdays
      INTO n_workdays
      FROM oworkdays
      WHERE thismonth=v_workmonth;[/color]   SELECT TO_CHAR( TRUNC(SUM(CEIL(fodate-fidate))/COUNT(*)) )
      INTO v_leadtime
      FROM oltstate
      WHERE outpdate >= bgtime_arg AND outpdate < endtime_arg;
   UPDATE omonthlyreport1
      SET ( input, inputinv, output, outputinv, scrapfab, scraptest )
              = ( SELECT input/n_workdays, inputinv/n_workdays, output/n_workdays,
                         outputinv/n_workdays, scrapfab/n_workdays, scraptest/n_workdays

                  FROM omonthlyreport1
                  WHERE thismonth=v_month AND pdno='zz1_total' ),
          leadtime = v_leadtime
      WHERE thismonth=v_month AND pdno='zz3_average';

   INSERT INTO omonthlyreport1(thismonth, pdno, scrapfab)
      VALUES(v_month, 'zz4_scraprat', (n_scrapsum/n_outsum)*100);
   INSERT INTO omonthlyreport1(thismonth, pdno, output)
      VALUES(v_month, 'zz5_yield', 100-(n_scrapsum/n_outsum)*100);

END monthly1;

The procedure is a little long and I think the red font has the relevance with this problem.

The trigger is:
CREATE OR REPLACE TRIGGER mao
   AFTER UPDATE OF updatetime 
   ON report_trigger
   FOR EACH ROW
DECLARE
   d_endtime report.endtime%TYPE;
   d_today   DATE;
BEGIN
   SELECT endtime
      INTO d_endtime
      FROM report
      WHERE id=:new.id;
   d_today := SYSDATE ;
IF :new.id = 99 AND TO_CHAR(d_endtime,'MON') != TO_CHAR(d_today,'MON') THEN
      monthly1( d_endtime, d_today );
      monthly3( d_endtime, d_today );
      monthly4( d_endtime, d_today );
      monthly5( d_endtime, d_today );
   END IF; 

   UPDATE report
      SET bgtime = d_endtime, endtime = d_today
      WHERE id=:new.id;
   
END after_update_report_trigger;

id        updatetime
99        2005-4-27 20:00:09