Question

我有一个实体包含列枚举类型。
定义列枚举在实体中的类型如下：

@Column(name = "gender", columnDefinition = "number(3)", nullable = false)
@Enumerated(EnumType.ORDINAL)
private Gender gender;

我在下面创建了一个hql查询：

SELECT customer.nationalCode AS nationalCode,
       customer.firstName AS firstName,
       customer.lastName  AS lastName,
       customer.gender AS gender
FROM Customer customer

此查询返回枚举类型的性别但我想获得性别序数而不是Enum Type 如何将列的枚举类型转换为整数？

Answer 1

我尝试使用spring boot测试应用程序，它对我有用的唯一方法是在HQL中将枚举转换为int：

SELECT customer.nationalCode AS nationalCode,
       customer.firstName AS firstName,
       customer.lastName  AS lastName,
       CAST(customer.gender AS int) AS gender
FROM Customer customer

我使用的模型基于您的示例：

@Entity
public class Customer {
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long id;
    private String nationalCode;
    private String firstName;
    private String lastName;
    @Column(name = "gender", columnDefinition = "number(3)", nullable = false)
    @Enumerated(EnumType.ORDINAL)
    private Gender gender;

    //getters and setters
}

和枚举：

public enum Gender {
    MALE, FEMALE;
}

编辑：这当然有效，如果你将enum作为ORDINAL保存在你的实体中（正如你现在所做的那样），否则你可能会得到一个NumberFormatException或类似的东西。

如何在hql查询中将列的枚举类型转换为整数？

1 个答案: