$o->thing1->thing2->thing3

##</code><code>##

SELECT thing2.thing3id FROM o, thing1, thing2 WHERE O.id= ? AND o.thing1_id = thing1.id AND thing1.thing2id = thing2.id

##</code><code>##

$o->thing123

##</code><code>##

SELECT thing123id FROM view123 WHERE o.id = ?