Difference in timestamp values

Question

Hi,
We have a project for like to like migration for R12 to R16, but ther are differences in the timestamp values calulated between the two enviornments
The R12 Production server is 5 hrs head of R16 production server.
i have applied the following formula to both the production report:
Timestampdiff(SQL_TSI_MINUTE,TIMESTAMP '2009-07-06 12:12:12',TIMESTAMP '2009-08-07 11:11:11')
the results are in Minutes:
R12:44578
R16:46019
Is this because of the difference in server timing? or R16 has a feature to calulate the difference without considering the timezones, daylight saving etc which the R12 lacks, because when i checked which of the 2 difference is correct, the R16 differnce seems to be correct.
Please share your thoughts on this as it is affecting large no .of reports.
Many Thanks

Answer 1

/* Formatted on 2012/04/12 15:56 (Formatter Plus v4.8.8) */
DECLARE
   v_time1       date;
   v_time2       date;
   v_time_diff   number;
BEGIN
   SELECT To_Date(TO_CHAR (wss_gdp_time, 'DD-MON-YYYY HH12:MI:SS'),'DD-MON-YYYY HH12:MI:SS')
     INTO v_time1
     FROM tab1
    WHERE wss_gdp_time = (SELECT MAX (wss_gdp_time)
                            FROM tab1) AND ROWNUM <= 1;
   SELECT to_Date(TO_CHAR (wss_gdp_time, 'DD-MON-YYYY HH12:MI:SS'),'DD-MON-YYYY HH12:MI:SS')
     INTO v_time2
     FROM tab1
    WHERE wss_gdp_time = (SELECT MAX (wss_gdp_time)
                            FROM tab1
                           WHERE wss_gdp_time < (SELECT MAX (wss_gdp_time)
                                                   FROM tab1))
      AND ROWNUM <= 1;
   SELECT ((v_Time1-v_time2) * 1440)
     INTO v_time_diff
     FROM DUAL;
   DBMS_OUTPUT.put_line (v_time1 || ' ' || v_time2 || ' ' || v_time_diff);
   IF v_time_diff > '10'
   THEN
      DBMS_OUTPUT.put_line ('ALERT');
   ELSE
      DBMS_OUTPUT.put_line ('No ALERT');
   END IF;
END;
/