- From: Jan Hidders <jan.hidders@ua.ac.be>
- Date: Mon, 24 May 2004 16:22:33 +0200
- To: Donald Spaeth <donald@spaeth.freeserve.co.uk>
- Cc: www-ql@w3.org
Donald Spaeth wrote:
>I've just been reviewing the proofs of an article I wrote last year on the
>use of XML to represent data derived from historical sources, and I realize
>that a passage on the many and wondrous uses of axes has been rendered
>obsolete by XPath 2.0 and XQuery. Can someone explain why the ancestor,
>preceding-sibling, and following-sibling axes have been dropped?
>
>
Actually, they have been put back in again, ... sort of. See the full
axis feature:
http://www.w3.org/TR/xquery/#id-full-axis-feature
If I recall correctly the two most important arguments against them were
there these axes are hard to type and hard to optimize. Personally I
find the second argument rather odd and I know that in some cases
certain optimizations become in fact more difficult if you don't have
these axes.
-- Jan Hidders
--
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Received on Monday, 24 May 2004 10:22:35 UTC