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   Re: [xml-dev] Streaming XML (WAS: More on taming SAX (was Re: [xm

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>     I've thought about using an XPath tracker in error reporting to
>     my library, which would be very simple to add at this point, and
>     it's necessary, I think because the document locator loses
>     meaning when I chain together a bunch of SAX filters.


>     In any case, I'm reading through some of the other articles
>     you've been posting. This is a very interesting discussion.

I read with great interest the whole discussion about XML streaming and 
and I have to admit that I am very confused by it.

Could you guys please try to clarify for me the answer to the following 
question: instead
hand coding steaming applications using SAX, couldn't you write some
XQuery code (with external functions probably) to do the same thing ?
Did you try at least ? Did you try and fail ? If yes, why did it fail ?

My hope is that at a certain point people will stop writing low level 
code, and they'll
rely on good implementations of XQuery to do the right amount of 
streaming, in the
optimal way. That should be vendor's problem, not user's problem.

Other question: why do you people care about "perfect" streaming, i.e. 
with zero memory consumption ? Between perfect streaming and total 
there is a world of possibilities in between, where materialization 
happens, but only
restricted to the minimum amount of data required to compute the 
answer, and only
for the minimum amount of time necessary to compute the correct answer.

Perfect streaming happens too rarely to be of any interest. What is 
interesting is all this
world in between.

Anyway, I believe that people shouldn't try to hand code their 
applications using low level
APIs like SAX or STAX, but use a higher level language like XSLT or 
XQuery, and trust the
XQuery/XSLT implementors that they'll  do a good job to minimize memory 
That's *their* job, not  *yours* as users.

But anyway, for those interested in streaming processing XML, the 
research might come in handy. There have been several studies of the 
problem in the
literature. For example you could find some of it at


  searching for "streaming XML"; starting from there you might find some 
interesting papers.

Best regards, happy holidays,


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