外键上的 JPQL JOIN 导致 SQLSyntaxErrorException

Question

我有两个实体 Order 和 Customer。 Order 与 Customer 有 @ManyToOne 关系。但是，当我声明以下 JPQL 查询时，我得到一个 SQLSyntaxErrorException，因为生成的 SQL 缺少 ON 条件。

JPQL:

SELECT o.id,
       o.incrementId,
       o.externalId,
       o.state,
       o.status,
       o.couponCode,
       o.totalDiscount,
       o.total,
       o.originChannel,
       o.branchOffice,
       o.createdAt,
       o.updatedAt,
       c.fullName
FROM Order o
JOIN FETCH Customer c;

生成SQL:

select order0_.id             as col_0_0_,
       order0_.increment_id   as col_1_0_,
       order0_.external_id    as col_2_0_,
       order0_.state          as col_3_0_,
       order0_.status         as col_4_0_,
       order0_.coupon_code    as col_5_0_,
       order0_.total_discount as col_6_0_,
       order0_.total          as col_7_0_,
       order0_.origin_channel as col_8_0_,
       order0_.branch_office  as col_9_0_,
       order0_.created_at     as col_10_0_,
       order0_.updated_at     as col_11_0_,
       customer1_.full_name   as col_12_0_
from orders order0_
inner join customers customer1_ on;

如您所见，它缺少条件 on。我觉得很奇怪，因为这些是我的实体：

Order（为了简洁省略不相关的属性）

@Entity
@Table(name = "orders")
public class Order {
    
   @Id
   @GeneratedValue(strategy = GenerationType.IDENTITY)
   private int id;
    
   @ManyToOne(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
   @JoinColumn(name = "customer_id", referencedColumnName = "id", table = "orders")
   private Customer customer;
    
   public Customer getCustomer() {
       return customer;
   }
}

Customer（为简洁起见省略不相关的属性）

我的用例不要求我在 Customer 实体 中有一个 List<Order>（我尝试添加它但没有解决无论如何都是问题。

@Entity
@Table(name = "customers")
public class Customer {
    
   @Id
   @GeneratedValue(strategy = GenerationType.IDENTITY)
   private int id;
    
   public int getId() {
      return id;
   }
    
   public void setId(int id) {
      this.id = id;
   }
}

这两个实体之间的关系是正确的，因为它在通过正常方式插入、更新和检索时按预期工作。我在这里遗漏了什么吗？

Answer 1

尝试使用以下jpql:

select o from Order o join o.customer

另见 documantation。

外键上的 JPQL JOIN 导致 SQLSyntaxErrorException

JPQL JOIN on Foreign Key causes SQLSyntaxErrorException

java

hibernate

jpql

spring-data