Re: [xml] Streaming XPath Support

["Stanley Poon (spoon)" <spoon cisco com>]

It is a nice feature. Are there any performance data available for the
improvements based on streaming XPath, like throughput, latency, etc?

As to the XSD validation, does it support full streaming based
validation? For example, full support for validation in SAX mode without
the need to keep tree.

Thanks,
Stanley
-----Original Message-----
From: Daniel Veillard [mailto:veillard redhat com] 
Sent: Tuesday, December 19, 2006 1:41 PM
To: Stanley Poon (spoon)
Cc: xml gnome org
Subject: Re: [xml] Streaming XPath Support

On Tue, Dec 19, 2006 at 11:01:45AM -0800, Stanley Poon (spoon) wrote:
> My understanding is that the current support is mainly for the 
> Selector in XSD.

  right though we also use it to speed-up simple XPath queries

> Are there any plan to enhance the support for streaming Xpath such as 
> //, *, simple predicates, etc.

  I take patches! Again that's something which Kasimier worked on and a
bit orphaned at this point.

> Also, is this internal feature added
> mainly for performance and for reducing memory usage?

  to be able to stream XSD validation without keeping trees around.

> Is the current implementation based on some finite state machine 
> approach with some path sharing?

  based on automatas, see pattern.c in the sources.

Daniel

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