2016-11-21 63 views
0

我具有低于类LEFT OUTER在休眠JOIN继承

@Inheritance(strategy=InheritanceType.JOINED) 
Class A{ 
private long a_id; 
private C C; 

} 

Class B extends A{ 
private D d; 
} 

Class C{ 
private long c_id; 
} 

Class D{ 
private long d_id; 
private Set<B> bs; 
} 

这里B类是延伸类A.试图如下查询

Criterion criterion = Restrictions.and(Restrictions.eq(
        "b.c", c_instance)); 

Criteria c = session.createCriteria(D.class, "d") 
c.createAlias("bs", "b",JoinType.LEFT_OUTER_JOIN,criterion); 
c.createAlias("bs.c","c") 

输出查询:

select d.d_id from D d left outer join B bs on d.d_id=bs.d_id and bs.c_id=2489 inner join A on bs.a_id=A.a_id inner join C A.c_id=C.c_id 

我得到一个错误,因为c_id在B中是未知列。虽然表B是没有其父表具有c_id列。我如何写一个查询来实现左外连接?

回答

0

我猜BS是一个集B类的,你正试图获取c.createAlias从B类,这是不存在的(“bs.c”,“C”)

+0

是的,C是不是B类的属性,但是它可以继承自A类而不发生。这是我的问题 –