Advice needed on placement of XML datatype validation methods

Amit Rekhi (amitr@abinfosys.com)
Thu, 1 Oct 1998 18:25:14 +0530

Hello,
I am in the process of attaching datatype validation routines
for element content in my XML file. I have come up with 2 approaches (as
listed below)., but am not sure which is a better one. If someone could
give their expert opinions ....

APPROACH 1

I can use NOTATIONS to identify data validation processes with element
content. eg.

<?xml version="1.0" ?>
<!DOCTYPE start-ele [
<!NOTATION Alphabet SYSTEM "AlphabetChecker.vld">
<!NOTATION Number SYSTEM "NumberChecker.vld">

<!ELEMENT start-ele (#PCDATA)>
<!ATTLIST start-ele datatype NOTATION (Alphabet|Number) "Alphabet">
]>
<start-ele datatype="Number">123</start-ele>

where AlphabetChecker.vld and NumberChecker.vld could contain validation
routines for checking alphabet and number datatypes.

APPROACH 2

I embed my datatype validation scripts in the XSL file I attach to my XML
data.I can embed my datatype validation scripts in HTML which will be
outputted by my XSL file (I am using XSL to do XML -> HTML transformation)
for elements in the XML file. In this case I could possibly use
(JScript/VBScript/JavaScript) as languages to implement my datatype
validation routines.

Which of the 2 approaches is better?

These 2 approaches bring out the basic questions:-

Where to place datatype validation routines for element content, in the
XML-DTD or in the XSL file attached to the XML data?

Thanks in advance,

AMIT REKHI