xpath Select nodes based on their children Select nodes based on specific child node
Example
Sample XML
<Students>
<Student>
<Name>
<First>Ashley</First>
<Last>Smith</Last>
</Name>
<Grades>
<Exam1>A</Exam1>
<Exam2>B</Exam2>
<Final>A</Final>
</Grades>
</Student>
<Student>
<Name>
<First>Bill</First>
<Last>Edwards</Last>
</Name>
<Grades>
<Exam1>A</Exam1>
</Grades>
</Student>
</Students>
XPath
Select all students that have a score for Exam2 recorded
//Student[./Grades/Exam2]
or
//Student[.//Exam2]
Output
<Student>
<Name>
<First>Ashley</First>
<Last>Smith</Last>
</Name>
<Grades>
<Exam1>A</Exam1>
<Exam2>B</Exam2>
<Final>A</Final>
</Grades>
</Student>
