Now it makes sense.  I haven't gone back to your book in sometime and I was
going off memory of not recalling mention of negative date fields.  Should
not have locked myself into that "negative" premise.  Thanks again for the
help.

Ed.



-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED] On Behalf Of Ralph Alvy
Sent: Tuesday, August 01, 2006 5:45 PM
To: DataPerfect Users Discussion Group
Subject: Re: [Dataperf] Using date to Reverse Index.

On Tue, 01 Aug 2006 17:04:41 -0700, E. Marfil, MAST UNITED  
<[EMAIL PROTECTED]> wrote:

> Hello Ralph.
>
> The incremental jump in values are weird but I'm not sure hot it  
> calculates.
> I have to look at it more closely.  In any case, it seems to be working.
>
> Thanks for your help and Brian's and Don's too.

The value stored by a DP Date field is the number of days since March 1,  
1900.

The value stored by a DP Time field is the number of seconds since  
midnight.

This way Date and Time fields can be subtracted from one another. For  
instance, 7/31/2006 minus 7/28/2006 equals 3, and 10:32:21 minus 10:31:5  
equals 76.

86400 is the number of seconds in a day.

So (P1F1*86400 + P1F2) is the number seconds since March 1, 1900, as of  
P1F1 P1F2, where P1F1 is the Date and P1F2 is the Time. A 10-digit  
numerical field will handle all possible values for this figure.

Read up on what I call the Moment function in my book.
_______________________________________________
Dataperf mailing list
[email protected]
http://lists.dataperfect.nl/mailman/listinfo/dataperf

_______________________________________________
Dataperf mailing list
[email protected]
http://lists.dataperfect.nl/mailman/listinfo/dataperf

Reply via email to