Specifying Constraint Fields

Constraint fields are XPath expressions used to define a constraint (unique, key or keyRef).

1. Open the property sheet of a constraint and then click the Fields tab.
2. Click in the XPath column and enter an XPath expression (see XPath abbreviated syntax).
3. Click the Properties tool to open the property sheet of the field:
   
   
   
4. [optional] Enter additional properties for the selector, and then click OK to return to the constraint.