RE: 00:00:00 or 24:00:00

This may have already been done in this long, long chain of notes (I didn't start reading these until recently), but let's look at what the system will generate when we add or subtract a microsecond toward the "end of the day":

dT1 s z inz(Z'2007-11-27-23.59.59.999999')
dT2 s z inz(Z'2007-11-28-00.00.00.000001')
dT3 s z

/free
T3 = T1 + %mseconds(1);
dsply T3;
T3 = T2 - %mseconds(1);
dsply T3;
T3 -= %mseconds(1);
dsply T3;
*inlr = *on;
return;
/end-free

This program displays:

DSPLY 2007-11-28-00.00.00.000000
DSPLY 2007-11-28-00.00.00.000000
DSPLY 2007-11-27-23.59.59.999999

The system works with a start of 00:00:00 but allows you to also (sometimes) use 24:00:00 if you so desire. There is no difference in time between the two though conceptually they are viewed/interpreted differently by people.

Bruce Vining

Glenn Gundermann <ggundermann@xxxxxx> wrote:
All this back and forth through the many e-mails is quite hexing.

Based on the quote below from Bruce's e-mail, am I correct in assuming the
following:

Nov. 28, 2007 0000 <> Nov. 28, 2007 2400
Nov. 28, 2007 2400 = Nov. 29, 2007 0000

Tks,

Glenn Gundermann
ggundermann@xxxxxx
(647) 272-3295

If memory serves me right, the use of 24:00:00, to refer to the end of the
day, is to accomodate previous (and long standing) standards used by the
military. As such ISO 8601 indicates:


day, calendar
time-interval starting at [0000] and ending at [2400] (which is equal to
the beginning of the next calendar day);
typically a calendar day has a duration of 24 h


It is confusing to have two accepted ways to represent the same point in
time and I do recall that this has always been a sore point with the
chief database architect back in Rochester -- but a point that he (and
us) have to live with...

Bruce Vining