java - Spring Data PostgreSQL Key already exists 错误

Question

我有以下 PostgreSQL 表:

CREATE TABLE IF NOT EXISTS levels (
    id SERIAL PRIMARY KEY,
    name VARCHAR(256),
    created_date timestamp,
    updated_date timestamp
);

和相应的 Spring Data 实体:

@Entity
@Table(name = "levels")
public class Level extends BaseEntity implements Serializable {

    private static final long serialVersionUID = 642499791438799548L;

    @Id
    @SequenceGenerator(name = "levels_id_seq", sequenceName = "levels_id_seq", allocationSize = 1)
    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "levels_id_seq")
    private Integer id;

    private String name;

...
}

@MappedSuperclass
public abstract class BaseEntity {

    @Column(name = "created_date")
    private Date createdDate;

    @Column(name = "updated_date")
    private Date updatedDate;

    @PrePersist
    void onCreate() {
        setCreatedDate(new Date());
    }

    @PreUpdate
    void onPersist() {
        setUpdatedDate(new Date());
    }

...
}

这是我的 Spring 数据级别存储库:

@Repository
public interface LevelRepository extends JpaRepository<Level, Integer> {

    Level findByName(String name);

}

现在，当我尝试使用 Spring LevelRepository 保存新的 Level 实体时，我收到以下错误:

ERROR:  duplicate key violates unique constraint « levels_pkey »
DETAIL: Key "(id)=(5)" already exists.

我的配置有什么问题？

Answer 1

如果您想保留GenerationType 而不是使用GenerationType.AUTO from that answer

并且错误的发生可能是由于在 data.sql 文件中进行了硬编码插入。

在实体中使用定义的顺序插入

INSERT INTO levels(id, name) VALUES (nextval('levels_id_seq'), 'test');

与 GenerationType.IDENTITY 相同，它将创建序列“%Your-table-name%_id_seq”。