不以逗号分隔的 Java JPA Left Join

Question

JPA结构中MYSQL结构翻译错误我有 100% 的 mysql 查询：SELECT DISTINCT * FROM list_orders LEFT JOIN orders_translate where list_orders._id=orders_translate._order_idquery JPA String query = "SELECT t1 FROM ListOrders t1 LEFT JOIN t1.speakers e WHERE e._id = t1._id";public class OrdersTranslate implements Serializable {private static final long serialVersionUID = 1L;@Id@GeneratedValue(strategy = GenerationType.IDENTITY)@Basic(optional = false)@Column(name = "_id")private Long id;@Size(max = 50)@Column(name = "_english_name")private String englishName;@Size(max = 50)@Column(name = "_arabic_name")private String arabicName;@Size(max = 50)@Column(name = "_russian_name")private String russianName;@Size(max = 50)@Column(name = "_french_name")private String frenchName;@Basic(optional = false)@NotNull@Column(name = "_order_id")private int order_id;}公共类 ListOrders 实现 Serializable {private static final long serialVersionUID = 1L;@Id@GeneratedValue(strategy = GenerationType.IDENTITY)@Basic(optional = false)@Column(name = "_id")@SerializedName("_id")private Integer id;@Basic(optional = false)@NotNull@Column(name = "_number_id")@SerializedName("_number_id")private int numberId;@Basic(optional = false)@NotNull@Size(min = 1, max = 50)@Column(name = "name")@SerializedName("name")private String name;@OneToOne(cascade = CascadeType.ALL)private List<OrdersTranslate> speakers;}我得到下一个错误：[53, 54] FROM 子句具有'ListOrders t1 LEFT JOINN t1.oerders'和'e'，它们没有用逗号分隔。[42, 53] 标识变量“t1.oerders”未遵循 Java 标识符的规则。[56, 56] 必须为范围变量声明提供标识变量。JPA查询有什么问题？MySQL 查询工作正常！

Answer 1

起初 - 如果您在 ListOrders 表中有 OrdersTranslate 数组，则您没有 OneToOne 连接。这是 OneToMany 加入。

请在您的 ListOrders 课程中尝试：

@OneToMany(mappedBy="listOrders")

private List<OrdersTranslate> speakers;

在您的 OrdersTranslate 类中：

@ManyToOne

@JoinColumn(name = "_order_id")

private ListOrders listOrders;

然后您的 JPA 查询将如下所示：

SELECT t1 FROM ListOrders t1 LEFT JOIN t1.speakers e