RE: [xml-dev] What is the difference between XSD and DTD

["Michael Kay" <mike@saxonica.com>]

In terms of validation functionality, XSD can define all the constraints that a DTD can define, and many more. To take a simple example, XSD can say that a particular attribute must be a valid date, or a number, or a list of URIs, or a string that is exactly 8 characters long. To take another example, XSD can define much richer constraints on uniqueness of values within a document.

 

I've no idea what you mean by "cross validate". I believe the only things you can do with a DTD that you can't do with an XML Schema are things that have nothing to do with validation: notably, defining entities.

 

Michael Kay

http://www.saxonica.com/

---

From: Saha Rabindra N [mailto:saha.rn@mellon.com]
Sent: 27 April 2005 22:10
To: xml-dev@lists.xml.org
Subject: [xml-dev] What is the difference between XSD and DTD
Importance: High

Hello,

  Can anybody please explain me the real difference between XSD and DTD. Because both are used to define the schema of an XML document.

Whereas DTD is more powerful in the sense that XML parser can cross validate an XML document based on its DTD, and this is really useful in business world as XML is mostly used to exchange the data between parties.

On the other hand XSD defines the schema in XML syntax only which is more readable, but XML parser CAN NOT cross validate one XML document based on a given XSD.

 

Then I am not understanding why people go for XSD ?

 

Can some body correct me please !

Thanks in advance,

 

Regards,

Rabindra Nath Saha

 

 

The information contained in this e-mail may be confidential and is intended solely for the use of the named addressee.

Access, copying or re-use of the e-mail or any information contained therein by any other person is not authorized.

If you are not the intended recipient please notify us immediately by returning the e-mail to the originator.(17b)