That=A1=AFs a pity that there is no real application having identity =
constraints, maybe because that feature is quite advanced. Anyway, =
thanks for your info. The differences between identity constraint and =
other regular expressions are mostly listed below, which makes me =
concern the runtime overhead of identity constraint support in the real =
application usage. 

1.     Identity constraint processing creates dependence between =
validations in different SAX events, which make it hard for further =
advanced optimization; while regular expression in schema validation can =
be processed in a single SAX event validation.

2.     Identity constraint requires typed based comparison, which might =
involve a lot of table/value-object/memory management, type conversion =
and string operations during validation; while regular expression =
processing is relatively simple: accepted or not accepted.

 

Best Regards

Yongnian

________________________________

From: Michael Kay [mailto:mike@s...] 
Sent: 2007=C4=EA5=D4=C211=C8=D5 15:49
To: Le, Yongnian; xmlschema-dev@w...
Cc: Jones, Kevin; Yu, Zhiqiang
Subject: RE: is there any formal commercial identity constraint cases

 

Thanks for the explanation. I'm not aware of any public domain material =
that can be used for performance benchmarking of schema processors, =
whether it's concerned with identity constraints or anything else. Is =
there any particular reason why you think identity constraints should be =
a problem, as distinct from, say, validation of strings against complex =
regular expressions?

 

Michael Kay

http://www.saxonica.com/

	 

=09
________________________________


	From: Le, Yongnian [mailto:yongnian.le@i...] 
	Sent: 11 May 2007 02:43
	To: Michael Kay; xmlschema-dev@w...
	Cc: Jones, Kevin; Yu, Zhiqiang
	Subject: RE: is there any formal commercial identity constraint cases

	I mean that whether there is any real customer case which contains =
identity constraint for us to use that as benchmark to measure =
performance of identity constraint support. Currently I only found there =
are hundreds of identity constraint unit cases in w3c XML Test Suite, =
but I am afraid that all of them are not representative enough in the =
real world used by customer. 

	 

	Best Regards

	Yongnian

=09
________________________________


	From: Michael Kay [mailto:mike@s...] 
	Sent: 2007=C4=EA5=D4=C210=C8=D5 17:42
	To: Le, Yongnian; xmlschema-dev@w...
	Cc: Jones, Kevin; Yu, Zhiqiang
	Subject: RE: is there any formal commercial identity constraint cases

	 

	I'm not sure what you mean by "formal", "commercial", or =
"benchmarking".

	 

	Michael Kay

	http://www.saxonica.com/

		 

	=09
________________________________


		From: xmlschema-dev-request@w... =
[mailto:xmlschema-dev-request@w...] On Behalf Of Le, Yongnian
		Sent: 10 May 2007 09:52
		To: xmlschema-dev@w...
		Cc: Jones, Kevin; Yu, Zhiqiang
		Subject: is there any formal commercial identity constraint cases

		Hi everyone, 

		 

		Do you know whether there is any formal commercial identity constraint =
case available for benchmarking? Thanks a lot!

		 

		"I hear and I forget, I see and I remember, I do and I understand" -- =
quoted by Yongnian

		ICSC Compiler

		Le, Yongnian

		8752-6253