xml - XSD How to generate sequence/record number in a unbounded field? -

I have an XSD with a field called "Client" which is minOccurs = 0 and maxOccurs = unbound whether that customer entry Is there any way to automatically attach sequence numbers?

Typically generated XML will look like this:

  & lt; Customerupdate & gt; & Lt; Customer record = "1" & gt; & Lt; Fname & gt; Albert & lt; / Fname & gt; & Lt; / Customer & gt; & Lt; Customer Record = "2" & gt; & Lt; Fname & gt; David & lt; / Fname & gt; & Lt; / Customer & gt; & Lt; / Customerupdate & gt;    
 
 
 You can not do whatever you like.  
 You define the default or fixed values ​​for attributes only, but only static values ​​are default / fixed