Date in apex

Question

The below given function gives result as 1 in apex when the max_date and min_date are same. But when run on toad it gives result 0.
CREATE  FUNCTION D_DIFF (max_date STRING, min_date STRING)
RETURN PLS_INTEGER IS
BEGIN
  RETURN TO_DATE(max_date) - TO_DATE(min_date);
EXCEPTION
  WHEN OTHERS THEN
  RETURN NULL;
END d_diff;Please advise.
Sanjay

Answer 1

Hi Sanjay,
The main problem is with date handling. Following are the two suggestions to follow:
1) Pass date in particular format in STRING parameters (say 'DD-MON-RR'), then the function will be:
create or replace FUNCTION D_DIFF (max_date STRING, min_date STRING)
RETURN PLS_INTEGER IS
BEGIN
  RETURN TO_DATE(max_date,'DD-MON-RR') - TO_DATE(min_date,'DD-MON-RR');
EXCEPTION
  WHEN OTHERS THEN
  RETURN NULL;
END d_diff;2) Directly pass date as parameters to the function, then the function will be:
create or replace FUNCTION D_DIFF (max_date DATE, min_date DATE)
RETURN PLS_INTEGER IS
BEGIN
  RETURN (max_date - min_date);
EXCEPTION
  WHEN OTHERS THEN
  RETURN NULL;
END d_diff;REMEMBER: TO_DATE(str,fmt)
1) TO_DATE converts str of CHAR, VARCHAR2, NCHAR, or NVARCHAR2 datatype to a value of DATE datatype. The fmt is a datetime model format specifying the format of str. If you omit fmt , then str must be in the default date format.
2) The default date format is determined implicitly by the NLS_TERRITORY initialization parameter or can be set explicitly by the NLS_DATE_FORMAT parameter.
Hope it helps!
Regards,
Kiran