<school>
	<student>
		<name>ivanov</name>
		<age> 15 </age>
	</student>
	<student>
		<name>petrov</name>
		<age> 16 </age>
	</student>
	<student>
		<name>sidorov</name>
		<age> 18 </age>
	</student>
</school>

select * from dbSchool
where ...