Question

我正在使用JPA和Hibernate 4作为提供者，我有以下实体：

@Entity
public class Customer {

    @Id
    private String id;

    private String name;

    @OneToMany(cascade=CascadeType.ALL)
    @JoinTable(name="customers_phones",
            joinColumns={@JoinColumn(name="id_customer")},
            inverseJoinColumns={@JoinColumn(name="id_phone")}
            )
    private List<Phone> phones;

    .. Getters/Setters ..
}

@Entity
public class Phone {

    @Id
    private String id;

    private String number;

    .. Getters/Setters ..
}

我有以下JPQL：

SELECT c FROM Customer c INNER JOIN c.phones p WHERE p.id = :phone

Hibernate为其生成以下SQL：

select
    customer0_.id as id1_0_,
    customer0_.name as name2_0_ 
from
    Customer customer0_ 
inner join
    customers_phones phones1_ 
        on customer0_.id=phones1_.id_customer 
inner join
    Phone phone2_ 
        on phones1_.id_phone=phone2_.id 
where
    phone2_.id=?

我希望Hibernate生成如下的SQL（即没有加入表'Phone'）：

select
    customer0_.id as id1_0_,
    customer0_.name as name2_0_ 
from
    Customer customer0_ 
inner join
    customers_phones phones1_ 
        on customer0_.id=phones1_.id_customer 
where
    phones1_.id_phone=?

我知道我可以将新实体映射到连接表'customers_phones'将它关联到Customer并在查询中使用它，或者我可以使用本机SQL而不是JPQL，但我想知道是否有更好的方法来实现这个（没有改变实体模型，仍然使用JPQL），也许是一些特定于Hibernate的Query Hint？

是否可以优化Hibernate生成的SQL与JoinTable的OneToMany关系？

0 个答案: