[egenix-users] mx.DateTime: Truncating fractional seconds

[Steve Holden]

> -----Original Message-----
> From: egenix-users-bounces at lists.egenix.com
> [mailto:egenix-users-bounces at lists.egenix.com]On Behalf Of
> Wade Leftwich
> Sent: Tuesday, August 19, 2003 2:26 PM
> To: sholden at holdenweb.com
> Cc: eGenix.com User Mailinglist
> Subject: Re: [egenix-users] mx.DateTime: Truncating fractional seconds
>
>
> M.-A. Lemburg wrote:
> > [put the list back on CC since I believe this is of interest
> >  to others as well]
> >
> > Steve Holden wrote:
> >
> >>> I'm not sure what you mean. If it's the warnings that you get in
> >>> Python 2.3 from the time module functions if you pass in the
> >>> .tuple() value due to mxDateTime representing the seconds as
> >>> float, then this problem will be gone in 2.1.0 final (I decided
> >>> to make seconds in the .tuple() output an integer; the float
> >>> value is still available through the .seconds attribute).
> >>>
> >>> If you're talking about the str() representation which includes
> >>> fractions, then the easiest way to get rid off the fractions
> >>> is use .strftime() which doesn't handle fractions of a second
> >>> by nature :-)
> >>
> >>
> >> I'm actually talking about using a DateTime object as a
> parameter for
> >> inserting into an Access Date column, specifically in this
> case under
> >> Python 2.2.x:
> >
> >
> > Ah, ok. AFAIR, Access tells mxODBC to send the date as string
> > and since mxDateTime instances generate seconds with fractions
> > which Access doesn't support, you get the warning.
> >
> > This simple trick should work:
> >
> > def AccessDateTime(dt):
> >     # cut away the seconds fraction part
> >     return str(dt)[:-3]
> > curs.execute(stmt, (AccessDateTime(now()),)
> >
> >> $ python
> >> Python 2.2.3 (#1, Jun 19 2003, 12:10:13)
> >> [GCC 3.2 20020927 (prerelease)] on cygwin
> >> Type "help", "copyright", "credits" or "license" for more
> information.
> >>
> >>>>> import mx.ODBC.Windows as db
> >>>>> conn = db.connect("billing")
> >>>>> curs = conn.cursor()
> >>>>> from mx.DateTime import now, DateTime
> >>>>> curs.execute("INSERT INTO Task (pjName, TaskName,
> Description, Rate,
> >>
> >>
> >> Started)"
> >> ...              " VALUES('gpcc', 'TEST', 'Delete me after this!',
> >> 125.0, ?)",
> >> ...              (now(), ))
> >> Traceback (most recent call last):
> >>   File "<stdin>", line 3, in ?
> >> mx.ODBC.Windows.Warning: ('01S07', 13, '[Microsoft][ODBC Microsoft
> >> Access Driver]Fractional truncation (null)', 5696)
> >>
> >>>>> n = now()
> >>>>> curs.execute("INSERT INTO Task (pjName, TaskName,
> Description, Rate,
> >>
> >>
> >> Started)"
> >> ...              " VALUES('gpcc', 'TEST', 'Delete me after this!',
> >> 125.0, ?)",
> >> ...              (DateTime(n.year, n.month, n.day, n.hour,
> n.minute,
> >> int(n.second)), ))
> >> 1
> >>
> >> Unfortunately I'd already tried Wade's int() trick on the
> whole date,
> >> without success in Access, I'm afraid, so it's interesting
> to know it
> >> works with MS SQL Server:
> >>
> >>
> >>>>> curs.execute("INSERT INTO Task (pjName, TaskName,
> Description, Rate,
> >>
> >>
> >> Started)"
> >> ...              " VALUES('gpcc', 'TEST', 'Delete me after this!',
> >> 125.0, ?)",
> >> ...             (int(n), ))
> >> Traceback (most recent call last):
> >>   File "<stdin>", line 3, in ?
> >> mx.ODBC.Windows.DataError: ('22003', 34, '[Microsoft][ODBC
> Microsoft
> >> Access Driver]Numeric value out of range (null)', 5696)
> >>
> >> Maybe the DateTime.__int__() method could be defined in
> some helpful way
> >> here?
> >
> >
> > int(datetime) returns the Unix ticks value for the datetime
> > you pass in. It is not meant to be used in this context.
> > The idea is that you can pass DateTime instances to other
> > functions which expect a Unix ticks integer.
> >
>
> In case there is still interest in this topic, I ran into the same
> situation this afternoon, and did it this way:
>
>  >>> from mx import DateTime
>  >>> def truncFractionalSeconds(dt):
> ... 	"""mxDateTime object => same with fractions of secs removed"""
> ... 	return DateTime.DateTimeFromTicks(int(dt))
> ...
>  >>> now = DateTime.now()
>  >>> now
> <DateTime object for '2003-08-19 14:19:27.11' at 150b9e0>
>  >>> truncFractionalSeconds(now)
> <DateTime object for '2003-08-19 14:19:27.00' at 14f8be0>
>  >>>
>
> Seems to me like it's safer to pass your cursor a DateTime
> object than a
> string, which might lead to cross-platform problems.
>
You're quite right, Wade. Coo, wish *i* had a brain ...

Seriously, I'll change the code to do it this wayt, it seems much saner
to use methods than external procedures.

regards
--
Steve Holden                                 http://www.holdenweb.com/
Python Web Programming                http://pydish.holdenweb.com/pwp/