• From: "Jim Wilson" <jim.wilson@k...>
• To: <xml-dev@l...>
• Date: Thu, 29 Jan 2009 10:41:41 -0600

Roger,

One comment for you...

> 5. If there is markup (data) needed by the 
> receiver but not the producer then make it
> optional. Thus the producer can omit the
> optional markup while the receiver can add it.

By "make it optional" I assume you mean--using XSD for example--to set
minOccurs="0" in a type definition. If that is true then these are the
cases in which, in my experience, "make it optional" is appropriate:

1) Element/attribute is required in some contexts and not in others. The
context that determines whether an element/attribute is required is
applied (and sometimes determined) at the time the document is
created/modified, not at schema design-time.

2) The receiver desires, but does not require, the element/attribute.
For example, distributors reporting certain sales information to
suppliers. Suppliers want the information but distributors are reluctant
to provide it without sufficient incentives. (One could argue that this
case is a subset of #1, but I thought it worth defining separately).

I hope this helps.

Best regards,
Jim Wilson

• References:
  • Keep business-process-specific data separate?
    • From: "Costello, Roger L." <costello@m...>
  • RE: Keep business-process-specific data separate?
    • From: "Costello, Roger L." <costello@m...>