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RE: Why not reinvent the wheel?
- From: Jonathan Robie <Jonathan.Robie@SoftwareAG-USA.com>
- To: xml-dev@lists.xml.org
- Date: Sat, 24 Feb 2001 15:15:12 -0500
Joe English wrote:
>Jonathan Robie wrote:
>
>I wouldn't go that far either; the structure of XQuery does look
>to me like it's more amenable to optimization than XSLT.
>But the '..' axis is definitely problematic.
[ !! SNIP !! ]
> In fact with lazy evaluation and a bit of care,
>you can obtain good space usage almost for free (see for example HaXML).
Hmmm ... I asked myself why Joe English knows about HaXML, went to his web
site, and realized that this is the Joe English who did Cost
(http://www.flightlab.com/cost/)
>But with '..', an end-user can define all the other XPath axes:
>
> -- modulo typos and type errors...
> FUNCTION ancestor(ELEMENT $e) RETURNS LIST(ELEMENT)
> {
> $e/.. UNION ancestor($e/..)
> }
Well, yes.
Now the question - if a user chooses to write recursive functions to do
this sort of thing, does that user have the right to expect that we will
optimize such queries well?
Jonathan
These are my opinions right now. They may be quite different from the
opinions of Software AG, the W3C XML Query Working Group, or the opinions
that I will have after reading and considering your response.