在多对一中使用 Spring Data JPA 保持错误关系

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【中文标题】在多对一中使用 Spring Data JPA 保持错误关系【英文标题】:Error relationship persistence using Spring Data JPA in a many to one 【发布时间】:2021-08-08 06:47:32 【问题描述】:

我有以下代码用于使用 Spring JPA 进行多对多或多对一关系持久性。

这是我的存储库测试https://github.com/Truebu/testJpa.git

这个类有三个一对多的关系,但没有一个很好用

@Entity(name = "routine_assignament")
@Table(name = "routine_assignament")
public class RoutineAssignament 

    @Id
    @GeneratedValue(strategy = IDENTITY)
    @Column(name = "id", updatable = false)
    private Long id;

    @Column(name = "date_start",nullable = true,columnDefinition = "DATE")
    private Date date_start = new Date();

    @Column(name = "date_end",nullable = true,columnDefinition = "DATE")
    private Date date_end;

    @ManyToOne
    @JoinColumn(name = "id_user")
    private User user;

    @ManyToOne
    @JoinColumn(name = "id_routine")
    private Routine routine;

    @OneToMany(mappedBy = "routine_assignament")
    private Set<Score> scores = new HashSet<>();

    @OneToMany(mappedBy = "routine_assignament")
    private Set<Statistic> statistics = new HashSet<>();

    @OneToMany(mappedBy = "routine_assignament")
    private Set<KeepRoutine> keepRoutines = new HashSet<>();

其他类

@Entity(name = "score")
@Table(name = "score")
public class Score 

    @Id
    @GeneratedValue(strategy = IDENTITY)
    @Column(name = "id", updatable = false)
    private Long id;

    @Column(name = "commentary",nullable = false,columnDefinition = "TEXT", unique = true)
    private String commentary;

    @Column(name = "assessment",nullable = false,columnDefinition = "INT", unique = true)
    private String assessment;

    @ManyToOne
    @JoinColumn(name = "id_routine_assignament")
    private RoutineAssignament routineAssignament;


@Entity(name = "statistic")
@Table(name = "statistic")
public class Statistic 

    @Id
    @GeneratedValue(strategy = IDENTITY)
    @Column(name = "id", updatable = false)
    private Long id;

    @Column(name = "time",nullable = false,columnDefinition = "TEXT", unique = true)
    private String time;

    @ManyToOne
    @JoinColumn(name = "id_routine_assignament")
    private RoutineAssignament routineAssignament;


@Entity(name = "keep_routine")
@Table(name = "keep_routine")
public class KeepRoutine 

    @Id
    @GeneratedValue(strategy = IDENTITY)
    @Column(name = "id", updatable = false)
    private Long id;

    @ManyToOne
    @JoinColumn(name = "id_routine_assignament")
    private RoutineAssignament routineAssignament;


实体关系图是这样的:

我的错误是它没有正确检测这些关系。

当我运行它时,它会生成:

Failed to initialize JPA EntityManagerFactory: mappedBy reference an unknown target entity property: com.example.demo.model.entities.KeepRoutine.routine_assignament in com.example.demo.model.entities.RoutineAssignament.keepRoutines

这个错误在所有三个类(KeepRoutine、Statistic 和 Score)中都出现了,我不知道为什么

【问题讨论】:

【参考方案1】:

您的OneToMany 映射不合适。您需要使用routineAssignament 属性名而不是表名routine_assignament,如下所示。此属性名称在ManyToOne 关系中定义。

    @OneToMany(mappedBy = "routineAssignament")
    private Set<Score> scores = new HashSet<>();

    @OneToMany(mappedBy = "routineAssignament")
    private Set<Statistic> statistics = new HashSet<>();

    @OneToMany(mappedBy = "routineAssignament")
    private Set<KeepRoutine> keepRoutines = new HashSet<>();

【讨论】:

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