RE: Data Model: Date and Time

I've passed this note along to the group.  We're in touch with the XML
Schemas group and hope to work closely with them on these and similar
issues.  You should see the fruits of these discussions in future drafts.

Thanks for the input.

Rob

-----Original Message-----
From: Steffen Goeldner [mailto:sgoeldner@eurodata.de]
Sent: May 18, 2000 8:49 AM
To: www-forms@w3.org
Subject: Data Model: Date and Time


Hi,

I cannot agree with the separation of 'Date ' and 'Time of Day'!
'Time of Day' is left truncated and only useful for
the specification of a recurring event. XML-Schema
is much clearer about that and named it 'recurringInstant'.
It's very easy to incoporate the time part into the
'Date' datatype: a simple merge of the values of the facet
'precision'.
Moreover, the separation of the types is difficult to handle
if you use they in expressions like 'above' or 'below'.

I can advice an excellent paper about time and granularity
(precision):

 Efficiently Supporting Temporal Granularities 
 Curtis E. Dyreson, William S. Evans, Hong Lin, Richard T. Snodgrass 
 September 3, 1998 
 TR-31 
 A TIMECENTER Technical Report 
 URL: <http://www.cs.auc.dk/research/DBS/tdb/TimeCenter/> 


Steffen Goeldner

Received on Thursday, 18 May 2000 10:59:15 UTC