You can create an XPath query predicate to filter element or attribute values in a view. For example, to extract employees in department 100, create the following XPath query predicate:
EMPLOYEE [./DEPT = '100']
The query expression is in brackets. The XPath of Dept is abbreviated by “./” to indicate that the path is continuing from Employee.
The following XPath query predicate extracts employees if the last name is Smith:
EMPLOYEE[./NAME/LASTNAME='SMITH']
Name is a child element of Employee and is the parent of Lastname.
Use Boolean or numeric operators in an XPath query predicate. You can also use string, numeric, and boolean functions in a query.