RE: Optional indicator in direct element and attribute constructors.

My experience with the FOR XML construction syntax which maps relational
data to XML is that a large amount of people (but not all) want NULL
values (the equivalent value to ()) mapped to absent properties. So
having a syntactic short-form in XQuery for such construction seems like
a more user-friendly approach. However, I am somewhat disturbed by the
proposed syntactic approach. Would it be better, if we add it first to
the computed constructors?

Best regards
Michael

> -----Original Message-----
> From: public-qt-comments-request@w3.org 
> [mailto:public-qt-comments-request@w3.org] On Behalf Of Michael Kay
> Sent: Friday, May 13, 2005 8:34 AM
> To: 'Mike Carey'; 'David Carlisle'; 'Daniel Engovatov'
> Cc: public-qt-comments@w3.org
> Subject: RE: Optional indicator in direct element and 
> attribute constructors.
> 
> 
> > So do this for every element- or attribute-constructing line of a 
> > query that constructs a new multi-hundred-line XML fragment 
> (e.g., a 
> > message
> > transformation) and you'll undertand the paragraph. 
> 
> If you need to do the same thing repeatedly, put it in a 
> function. Or in this case, add a second step to the 
> processing pipeline that strips out all empty elements and attributes.
> 
> We can't invent custom syntax for everything that anyone ever 
> wants to do.
> 
> Michael Kay
> 
> 
> 
> > 
> > -----Original Message-----
> > From: public-qt-comments-request@w3.org 
> > [mailto:public-qt-comments-request@w3.org] On Behalf Of 
> David Carlisle
> > Sent: Friday, May 13, 2005 6:44 AM
> > To: Daniel Engovatov
> > Cc: public-qt-comments@w3.org
> > Subject: Re: Optional indicator in direct element and attribute 
> > constructors.
> > 
> > 
> > 
> >   Producing this result using computed constructors, conditional
> >   statements and custom functions turns out to be quite inelegant,
> >   cumbersome and hard to maintain.
> > 
> > don't you just need to replace
> > <b>...</b>
> > by
> > 
> > let $x := <b>...</b>
> > return
> > if ($x/node()) then $x else ()
> > 
> > David (non WG reply)
> > 
> > 
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Received on Friday, 13 May 2005 15:48:51 UTC