Re: Time zone handling in QT

Hello Martin,

On Sat, 30 Jul 2005 13:49:26 +0900, Martin Duerst <duerst@it.aoyama.ac.jp>  
wrote:

> Hello Felix,
>
> Some comments below.
>
> At 16:44 05/07/27, Felix Sasaki wrote:
>  >
>  >Hi Addison, hi all,
>  >
>  >I made some concrete proposals for XQuery / XSLT users and integrated  
> them
>  >into the Wiki [1]. Please comment them / change them as you like. I  
> added
>  >the following:
>  >
>  >Recommendations for XQuery / XSLT
>  >
>  >The following recommendations are for users of XQuery / XSLT who have  
> to
>  >deal with time zone sensitive data:
>
> I think this is the wrong start. Many people will think that it
> doesn't concern them. But most people are affected, sooner or
> later. The intro should make that clear.

That's a good point. I will change that to:

"The following recommendations are for users of XQuery / XSLT. They should  
take them into account even if they do not deal with time zone sensitive  
data regulary, since sooner or later they will be affected by the issues  
described."

Regards, Felix.

>
> Regards,   Martin.
>
>
>  >    1.
>  >       If possible, make sure that your data always contains an  
> explicit
>  >time zone which should be UTC (i.e. computer time).
>  >    2.
>  >       Do not apply any operations based on date / time types (e.g.
>  >indexing) if you are not sure (a) whether your data has time zone
>  >information at all, or (b) whether the data collection might encompass  
> a
>  >data subset without timezones or might mix computer and wall time.
>  >    3.
>  >       If you have data like 2, before applying any date / time  
> sensitive
>  >operations, adjust the time zone of the data to UTC with the functions  
> for
>  >time zone adjustment, cf. [WWW]
>  >http://www.w3.org/TR/xpath-functions/#timezone.functions.
>  >    4.
>  >       If you have data like 2 (b) and you do not want to adjust the  
> data
>  >subset which already has a time zone, make sure that you recognize this
>  >data subset, e.g. via the component extraction functions [WWW]
>  >http://www.w3.org/TR/xpath-functions/#d1e4771.
>  >
>  >
>  >-- Felix
>  >
>  >[1] http://esw.w3.org/topic/i18nFAQTimeZone
>  >

Received on Saturday, 30 July 2005 16:17:00 UTC