Another Schema Question

["Bullard, Claude L (Len)" <clbullar@ingr.com>]

So"{fields} specifies XPath expressions relative to each element selected by
a {selector}. This must identify a single node (element or attribute, not
necessarily within the selected element) whose content or value, which must
be of a simple type, is used in the constraint. It is possible to specify an
ordered list of {fields}s, to cater to multi-field keys, keyrefs, and
uniqueness constraints. "

That paragraph needs a bit more work.  So:  

"This must identify a single node whose content of value is 
used in the contraint."  

Do all the parenthetical phrasing in a list or something.

So do fields specify a set of additional constraints or are these the
complete constraint 
set?  I am unclear as to the scope of the selector given that paragraph.

Len Bullard
Intergraph Public Safety
clbullar@ingr.com
http://www.mp3.com/LenBullard

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