How to make an element value unique within entire instance document?
posted 13 years ago
Hi, please take a look at this schema and tell me how I can make the value of my AttachmentKey element(s) unique within the entire instance document.
I know that I have to use <key> or <unique>, but I can't get it to work, as I don't have much knowledge of xpath.
here is my schema:
As you can see, AttachmentKey is a subelement of Attachment, and is used in more than one place in the example above. I want it so that when the instance document is created, no matter how many instances of Attachment is in it, each AttachmentKey value is unique, so that I can use them as keys.