gistfile1.py

mapper(Court, t.court_table, properties=dict(
    district = relation(District, backref='courts'),
    judges = relation(Judge, backref='court', 
                      order_by=[t.judge_table.c.last_name, 
                                t.judge_table.c.first_name,
                                t.judge_table.c.initials]),
    
    case_count=column_property(
        select([func.count(t.case_table.c.id)],
               t.case_table.c.court_id==t.court_table.c.id,
              ), deferred=True),
    unmatched_judges = relation(UnmatchedJudge, backref='court', cascade='delete',)
))


def query()
    q = LexSession.query(Court)
    q = q.join(Court.cases)
    q = q.filter(Case.tags.any(Tag.name == 'Patent'))
    q = q.order_by(Court.case_count)
    return q