HQL子查询不支持from

hql语句的from不支持子查询，where支持！ 
   如：

select a from A a,(select b from B b,C c where b.id=c.id) d 
       where a.id=d.id; 
  改为：

select a from A a where a.id in (select b.id from B b,C c 
       where b.id=c.id);