How to compare 2 dates ?

[beber005]

Hi every one

I mess with dates. In fact, I do a test on them to tell if A is greater than B, then do it otherwise do that and so on.
That's what I currently write code like:

Code: Select all

 # pMonth and pYear are my input parameters

vYM = '01-' | pMonth |'-' | pYear
vNewDate = DAYNO(vYM)

# vPastDate is an other date as same format as vNewdate
If(vNewdate > vPastDate);
	# do that
ENdIf;

Unfortunately it does not work in all cases. For example, when I compare the dates with the date 01-02-2011 04-05-2005 he told me that the date 2005 is> 2011. Yet this is totally false. Where can it come? Should we add a calculation on the dates for comparison?

Thanks a lot for your help

[Alan Kirk]

Hi every one

I mess with dates. In fact, I do a test on them to tell if A is greater than B, then do it otherwise do that and so on.
That's what I currently write code like:

Code: Select all

 # pMonth and pYear are my input parameters

vYM = '01-' | pMonth |'-' | pYear
vNewDate = DAYNO(vYM)

# vPastDate is an other date as same format as vNewdate
If(vNewdate > vPastDate);
	# do that
ENdIf;

Unfortunately it does not work in all cases. For example, when I compare the dates with the date 01-02-2011 04-05-2005 he told me that the date 2005 is> 2011. Yet this is totally false. Where can it come? Should we add a calculation on the dates for comparison?

Thanks a lot for your help

Ah. I see what your problem is. You're on the right track, but you're feeding the values into the DayNo function in the wrong order. You have to feed them as Year-Month-Day not Day-Month-Year. I suggest referring to this thread for an overview of working with dates and times.

[declanr]

And since you have to put it in the yyyymmdd format, if all you want to do is find out which one is more recent/older you can just convert them to numbers using stringtonumber()... same number of steps but just a different method.

e.g.

20130101 > 20120101
20130201 > 20130101
20130205 > 20130201

That way even as numbers they are also still recognisable to the user whereas serial numbers tend to not be.

[Alan Kirk]

Good suggestion from Declan, but just be careful that your year parameter is always 4 digits if you go down that path. Since it's a parameter (or appears to be) you may not have any control over that at runtime. The advantage of DayNo is that for the range 1 Jan 1960 to 31 Dec 2059 it can take either a 2 character year or a 4 character year and you'll get the correct result.

[beber005]

Thank's alan and declanr for your help. Alan actually you were right. I do not think that the order be able to change all that. And now it works perfectly