Relational sorting use case

This example shows how to sort the classroom data first by descending age, then by ascending name:

		DataSelection query = buildClassroomDataSelection();

		List resultItems = query.getResultItems();
		DataItem age = (DataItem) resultItems.get(1);
		DataItem name = (DataItem) resultItems.get(2);

		age.setSortDirection(DataItemActionType.SORT_DESCENDING);
		name.setSortDirection(DataItemActionType.SORT_ASCENDING);

		List sortItems = new ArrayList();
		sortItems.add(age);
		sortItems.add(name);

		//sort items in the order given by the list:
		query.setSortOrderPrecedence(sortItems);

		//execute the query

The result of the query is: