[AccessD] DateAdd vs +

Hi Debbie,

You MIGHT want to have a look at this article that describes a lot of
stuff about Access Date Fields

http://support.microsoft.com/default.aspx?scid=kb;en-us;130514

This article describes date field in Access. They are a double
precision numeric field with the data to the left of the decimals
representing the number of days since the beginning and the decimal
portion representing the fractional part of the day for the time. Day
number ZERO in this scheme is December 30, 1899. Dates before this
date are represented by Negative numbers and after are positive
numbers.

So the dateadd function and the simple math should both yield the same
result as they are only adding a number of days which is then
reformatted into whatever date format you have indicated after the
math is done. Dateadd is a great function when you are doing math for
other than days but for the example of adding days it would not seem
to me to matter.

I agree that the between says you should probably add 59 instead of 60
though. I'd make a test table and run some tests to be sure though as
I always get messed up with math ;-)

GK

On Mon, Jul 26, 2010 at 2:15 PM, Debbie <delam at zyterra.com> wrote:
> I have an existing app that gets date criteria for a report by adding
> 60 to the date.  Between me.datePicker and me.datePicker + 60. I am
> being asked some very specific questions about when it counts from. My
> unfderstanding is that this is a total of 61 days since between is
> inclusive. Now I use dateadd() instead of the date + x method. Do
> these potentially give different results, say if February or a leap
> year is included?
>
> Debbie
>
> Sent from my iPhone
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-- 
Gary Kjos
garykjos at gmail.com