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Re: performance wise, is there any difference between dtd validation v/s schema validation?

From: <jeffrafter@defined.net>
Date: Wed, 15 Aug 2001 20:56:23 -0400 (EDT)
Message-ID: <019901c125ee$20833b40$f181fea9@abraham>
To: "komal mangtani" <mkomal@bea.com>
Cc: <xmlschema-dev@w3.org>
> then which one's faster theoretically?

Difficult to answer-- because the rules for DTDs are simpler it is likely
that they would be faster- though the difference would be hardly
notoiceable.

> Let me ask this ,
> does xml schema ( being an xml by itself ) has a standard dtd ( maybe
defined
> by w3c ) to which it should conform?

Sort of-- there is an XMLSchema.Dtd but it is non-normative. It can be found
at http://www.w3.org/2001/XMLSchema (RDDL)

> If not, what is an xsd file validated against?  I don't think it is just
> checked for well-formedness.

It can also be checked against the Schema for Schemas though this is a bit
of a chicken/egg problem.

> I thought that as xml schema itself is an xml , the schema validation will
> take more time as it has to recursively check whether xsd is conforming to
dtd
> and as dtd is purely a raw format, that might be faster.

Yes and no-- The validation for DTDs (against the XML Spec) is built into
parsers-- it is checked as the DTD is read. Presumably this would happen in
an extremely optimized XML Schema validator as well-- it would not actually
use the XMLSchema.Dtd or Schema for Schemas.

This is all theory though-- best bet is to try it out...

Good Luck,
Jeff Rafter
Defined Systems
http://www.defined.net
XML Development and Developer Web Hosting
Received on Friday, 17 August 2001 05:49:14 GMT

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