On 25.11.2010 16:17, Simon Grant wrote:

>     Q: "When did this band play in your town?"
>     A: "They gave a concert at 2nd and 3rd June"
>     Q: "Oh, they started playing at 2nd and finished at 3rd?"
>     A: "No, they gave two shows, one at 2nd, one at 3rd."
>     Q: "But which date did they play?"
>     A: "At 2nd, and 3rd, as I said."
>     Q: "But '2nd and 3rd' is not a date!"
> And we aren't (I suggest) trying to represent "the" date of complex
> constructs like this. The reality is just as you say: there is a set of
> concerts, and each concert had a date (and a time interval within that
> date). Surely that is enough for any knowledge representation system.

There is no "the reality is just as you say" if you deal with data. If 
you do not want to allow entities to have multiple dates - fine. If you 
want to model entities with multiple dates - also fine. But none of the 
two choices is "enough" or "reality".

> Does anyone really want to represent dates of this kind of complex
> construct? If so, why on earth? If we can get a simpler specification by
> leaving out a doubtful edge case, I would suggest it was very much worth
> leaving it out.

Using the same argument I propose to replace all Date/Time Standards by 
the following easy specification. There are three values:


Surely that is enough for any knowledge representation system. Why on 
earth would anyone  want more complex dates? Relax, have a smoke and 
enjoy present! You can also think about past and the future, but don't 
be pedantic!


Jakob Voß <[log in to unmask]>, skype: nichtich
Verbundzentrale des GBV (VZG) / Common Library Network
Platz der Goettinger Sieben 1, 37073 Göttingen, Germany
+49 (0)551 39-10242,