From the design perspective, I agree with 
"Len".
The best is to separate these two values(numerical and 
units) . But this is possible if you are starting the Schema 
afresh.
but if the XML instance documents are already existing and 
we need to write a Schema for them and some how to validate, we can follow the 
method that I narrated in my last email(defining a regular expression constraint 
on the Simple type of attribute definition in the schema)
Thanks,
Sreeni



From: Bullard, Claude L (Len) 
[mailto:len.bullard@i...] 
Sent: Friday, March 03, 2006 
12:24 PM
To: Mangesh Kalbhor; xml-dev@l...
Subject: 
RE: [xml-dev] can attribute in XML schema hold value and 
unit



 
<FlowRate unitStuff="GPM 100" />
 
The 
best answer is, don't do that; it's bad design for 
reasons that are obvious (esentially, it is a token delimited 

list 
and has all the same problems of production order, 
catching errors late, all strings, etc.)
 
Make 
two attributes: one for unitType and one for unitValue.  

 
<FlowRate 
unitValue="100" unitType="GPM" />
 
It's clear and better for production and 
validation.

If 
these are basic types, say enumeration for the 
unitTypes and numbers for the values, attributes will work 

but 
are the least extensible.
 
A FlowRate element with an enumerated 
attribute for unit type.
 
<FlowRate unit="GPM">100</FlowRate>
 
Dealer's choice but the last one is the most robust.
 
len

  -----Original Message-----
From: Mangesh Kalbhor 
  [mailto:Mangesh.Kalbhor@a...]
Sent: Friday, March 03, 2006 
  2:08 PM
To: xml-dev@l...
Subject: [xml-dev] can 
  attribute in XML schema hold value and unit


  
  Hi 
  All,<o:p></o:p>
  <o:p> </o:p>
  I am creating a xml schema where I 
  have to making a ‘attribute’ but can a attribute hold a value and 
  unit.<o:p></o:p>
  My example is FlowRate, let’s the 
  value and unit could be 100 GPM.<o:p></o:p>
  Can I have just one attribute for 
  100 and GPM both. Some times it might be 80 cFPS.<o:p></o:p>
  <o:p> </o:p>
  So can a attribute hold both or do 
  I need element here.<o:p></o:p>
  <o:p> </o:p>
  Thanks,<o:p></o:p>
  <o:p> </o:p>
  Mangesh<o:p></o:p>