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Re: Ancestors and siblings

From: Jan Hidders <jan.hidders@ua.ac.be>
Date: Mon, 24 May 2004 16:22:33 +0200
Message-ID: <40B20529.4060308@ua.ac.be>
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 GMT

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