graph - How to do Exclusion Queries in OrientDB -

i'm wondering if it's possible use sub-selection exclusion query in orient db (v2.0). or if it's necessary export separate queries , process in java/php/etc.

for instance, have following graph hogwarts.

vertices people, houses, classes

edges is_at (subclasses is_student, is_faculty), was_at (alumni), is_taking, is_teaching, belongs_to

how find alumni aren't faculty? possible single query or using let somehow?

how find faculty teaching course on, say, time travel, have no students belong house gryffindor?

thanks, lindsay

the .size() operator should work: http://orientdb.com/docs/2.0/orientdb.wiki/sql-methods.html#size

select people out('is_faculty').size() = 0 

use out('...') or in('...') based on graph.

how find faculty teaching course on, say, time travel, have no students belong house gryffindor?

i don't have information on graph , classes, like:

select classes classname='time travel' , in('is_teaching')[id=yourid] , in('is_taking').out('belongs_to')[name='gryffindor'].size() = 0 

again, use in() or out() accordingly graph.