Java Hibernate外键必须具有与多对多上引用的主键相同的列数

我试图用JPA实现给定的数据库结构

SQL脚本：

DROP TABLE IF EXISTS StudentLesson;
DROP TABLE IF EXISTS StudentCourse;
DROP TABLE IF EXISTS Lesson;
DROP TABLE IF EXISTS Course;
DROP TABLE IF EXISTS Student;

CREATE TABLE IF NOT EXISTS Course
(
    courseId    BIGINT       NOT NULL AUTO_INCREMENT,
    name        VARCHAR(150) NOT NULL,
    description TEXT         NULL,
    actual      TINYINT      NOT NULL DEFAULT 1,
    PRIMARY KEY (courseId)
) ENGINE = InnoDB
  DEFAULT CHARSET = utf8mb4
  COLLATE = utf8mb4_unicode_ci;

CREATE TABLE IF NOT EXISTS Lesson
(
    lessonId    BIGINT       NOT NULL AUTO_INCREMENT,
    courseId    BIGINT       NOT NULL,
    name        VARCHAR(150) NOT NULL,
    orderNumber INTEGER      NULL,
    actual      TINYINT      NOT NULL DEFAULT 1,
    PRIMARY KEY (lessonId),
    CONSTRAINT FK__Lesson__courseId FOREIGN KEY Lesson (courseId) REFERENCES Course (courseId)

CREATE TABLE IF NOT EXISTS Student
(
    studentId BIGINT NOT NULL AUTO_INCREMENT,
    userId    BIGINT NOT NULL,
    PRIMARY KEY (studentId),
    CONSTRAINT FK__Student__userId FOREIGN KEY Student (userId) REFERENCES User (userId)
) ENGINE = InnoDB
  DEFAULT CHARSET = utf8mb4
  COLLATE = utf8mb4_unicode_ci;

CREATE TABLE IF NOT EXISTS StudentCourse
(
    studentCourseId  BIGINT        NOT NULL AUTO_INCREMENT,
    studentId        BIGINT        NOT NULL,
    courseId         BIGINT        NOT NULL,
    percentCompleted DECIMAL(5, 2) NOT NULL DEFAULT 0.0,
    PRIMARY KEY (studentCourseId),
    CONSTRAINT FK__StudentCourse__studentId FOREIGN KEY StudentCourse (studentId) REFERENCES Student (studentId),
    CONSTRAINT FK__StudentCourse__courseId FOREIGN KEY StudentCourse (courseId) REFERENCES Course (courseId)
) ENGINE = InnoDB
  DEFAULT CHARSET = utf8mb4
  COLLATE = utf8mb4_unicode_ci;

CREATE TABLE IF NOT EXISTS StudentLesson
(
    studentLessonId  BIGINT        NOT NULL AUTO_INCREMENT,
    studentCourseId  BIGINT        NOT NULL,
    lessonId         BIGINT        NOT NULL,
    percentCompleted DECIMAL(5, 2) NOT NULL DEFAULT 0.0,
    PRIMARY KEY (studentLessonId),
    CONSTRAINT FK__StudentLesson__studentCourseId FOREIGN KEY StudentLesson (studentCourseId) REFERENCES StudentCourse (studentCourseId),
    CONSTRAINT FK__StudentLesson__lessonId FOREIGN KEY StudentLesson (lessonId) REFERENCES Lesson (lessonId)
) ENGINE = InnoDB
  DEFAULT CHARSET = utf8mb4
  COLLATE = utf8mb4_unicode_ci;

以下是我的实体类： 学生

学生课程

@Entity
@Table(name = "StudentCourse")
@Getter
@Setter
public class StudentCourseDBO extends AbstractDBO {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "studentCourseId", nullable = false)
    private Long studentCourseId;

    @ManyToOne(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
    @JoinColumn(name = "studentId", nullable = false)
    private StudentDBO student;

    @ManyToOne(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
    @JoinColumn(name = "courseId", nullable = false)
    private CourseDBO course;

    @OneToMany(fetch = FetchType.LAZY, mappedBy = "studentCourse")
    private Set<StudentLessonDBO> studentLessons;

    @Column(name = "percentCompleted", nullable = false)
    private BigDecimal percentCompleted;

}

当我尝试启动我的应用程序时，它会给我错误的

外键（FKR8CMXBJOTBR91MTV62SAKWVA:StudentLesson[studentCourseId]）必须与引用的主键（StudentCourse[studentId，courseId]）具有相同的列数。

完整堆栈跟踪：

Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'jpaMappingContext': Invocation of init method failed; nested exception is org.hibernate.MappingException: Foreign key (FKr8cmxbjotnbr91mtv62sakwva:StudentLesson [studentCourseId])) must have same number of columns as the referenced primary key (StudentCourse [studentId,courseId])
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1788) ~[spring-beans-5.3.1.jar:5.3.1]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:609) ~[spring-beans-5.3.1.jar:5.3.1]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:531) ~[spring-beans-5.3.1.jar:5.3.1]
    at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:335) ~[spring-beans-5.3.1.jar:5.3.1]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234) ~[spring-beans-5.3.1.jar:5.3.1]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:333) ~[spring-beans-5.3.1.jar:5.3.1]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208) ~[spring-beans-5.3.1.jar:5.3.1]
    at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveReference(BeanDefinitionValueResolver.java:330) ~[spring-beans-5.3.1.jar:5.3.1]
    ... 28 common frames omitted
Caused by: org.hibernate.MappingException: Foreign key (FKr8cmxbjotnbr91mtv62sakwva:StudentLesson [studentCourseId])) must have same number of columns as the referenced primary key (StudentCourse [studentId,courseId])
    at org.hibernate.mapping.ForeignKey.alignColumns(ForeignKey.java:148) ~[hibernate-core-5.4.23.Final.jar:5.4.23.Final]
    at org.hibernate.mapping.ForeignKey.alignColumns(ForeignKey.java:130) ~[hibernate-core-5.4.23.Final.jar:5.4.23.Final]
    at org.hibernate.boot.internal.InFlightMetadataCollectorImpl.secondPassCompileForeignKeys(InFlightMetadataCollectorImpl.java:1929) ~[hibernate-core-5.4.23.Final.jar:5.4.23.Final]
    at org.hibernate.boot.internal.InFlightMetadataCollectorImpl.secondPassCompileForeignKeys(InFlightMetadataCollectorImpl.java:1845) ~[hibernate-core-5.4.23.Final.jar:5.4.23.Final]
    at org.hibernate.boot.internal.InFlightMetadataCollectorImpl.processSecondPasses(InFlightMetadataCollectorImpl.java:1665) ~[hibernate-core-5.4.23.Final.jar:5.4.23.Final]
    at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.complete(MetadataBuildingProcess.java:286) ~[hibernate-core-5.4.23.Final.jar:5.4.23.Final]
    at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.metadata(EntityManagerFactoryBuilderImpl.java:1224) ~[hibernate-core-5.4.23.Final.jar:5.4.23.Final]
    at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:1255) ~[hibernate-core-5.4.23.Final.jar:5.4.23.Final]
    at org.springframework.orm.jpa.vendor.SpringHibernateJpaPersistenceProvider.createContainerEntityManagerFactory(SpringHibernateJpaPersistenceProvider.java:58) ~[spring-orm-5.3.1.jar:5.3.1]
    at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:365) ~[spring-orm-5.3.1.jar:5.3.1]
    at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.buildNativeEntityManagerFactory(AbstractEntityManagerFactoryBean.java:409) ~[spring-orm-5.3.1.jar:5.3.1]
    at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264) ~[na:na]
    at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128) ~[na:na]
    at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628) ~[na:na]
    at java.base/java.lang.Thread.run(Thread.java:834) ~[na:na]

---

可能是什么问题？我是否使用多对多关系表StudentCourse错误？错误表明，StudentLesson必须有多个列引用，但在数据库中StudentCourse只有一个主键列（studentCourseId），而不是（studentId，courseId）。

AbstractDBO看起来怎么样？也许您也在那里声明了一个id？

AbstractDBO看起来怎么样？可能您也在那里声明了一个id？

您确定您的数据库没有处于过时状态“如果不存在，创建表”？是的，我每次都在执行DROP TABLE IF EXISTS。我更新了我的问题您确定您的数据库没有处于过时状态“如果不存在创建表”？是的，我每次都在执行DROP TABLE IF EXISTS。我更新了我的问题它只是一个实现Serializable的空抽象类问题是表

StudentCourse

的Hibernate模型有两列作为主键，所以这是您这边的映射问题。是否将表映射到多个实体？或者你有一个

@ManyToMany

的地方，你使用

StudentCourse

作为联接表吗？StudentCourse是学生和课程之间多对多关系的产物。通常情况下，StudentCourseDBO类甚至不会被创建，但我想将其作为一个单独的实体使用，并带有额外的字段和关系，在这种情况下，StudentLesson是一对多的。有没有办法将主键指定为一个ID字段而不是两个多对多关系字段？我不明白你在做什么，请用所有细节更新你的问题。无论如何，您不能以这种方式多次映射表。如果您将一个表映射为实体，则在希望映射到该表时应始终使用该实体，否则会出现类似这样的问题。它只是一个实现Serializable的空抽象类问题在于表的Hibernate模型

StudentCourse

有两列作为主键，所以这是你们这边的一个映射问题。是否将表映射到多个实体？或者你有一个

@ManyToMany

的地方，你使用

StudentCourse

作为联接表吗？StudentCourse是学生和课程之间多对多关系的产物。通常情况下，StudentCourseDBO类甚至不会被创建，但我想将其作为一个单独的实体使用，并带有额外的字段和关系，在这种情况下，StudentLesson是一对多的。有没有办法将主键指定为一个ID字段而不是两个多对多关系字段？我不明白你在做什么，请用所有细节更新你的问题。无论如何，您不能以这种方式多次映射表。如果将表映射为实体，则在希望映射到该表时应始终使用该实体，否则会出现类似这样的问题。

@Entity
@Table(name = "Lesson")
@Getter
@Setter
public class LessonDBO extends AbstractOrderedDBO {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "lessonId", nullable = false)
    private Long lessonId;

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "courseId", nullable = false)
    private CourseDBO course;

    @Column(name = "name", nullable = false)
    private String name;

    @Column(name = "actual")
    private Boolean actual;

}

@Entity
@Table(name = "StudentCourse")
@Getter
@Setter
public class StudentCourseDBO extends AbstractDBO {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "studentCourseId", nullable = false)
    private Long studentCourseId;

    @ManyToOne(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
    @JoinColumn(name = "studentId", nullable = false)
    private StudentDBO student;

    @ManyToOne(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
    @JoinColumn(name = "courseId", nullable = false)
    private CourseDBO course;

    @OneToMany(fetch = FetchType.LAZY, mappedBy = "studentCourse")
    private Set<StudentLessonDBO> studentLessons;

    @Column(name = "percentCompleted", nullable = false)
    private BigDecimal percentCompleted;

}

@Entity
@Table(name = "StudentLesson")
@Getter
@Setter
public class StudentLessonDBO extends AbstractDBO {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Column(name = "studentLessonId", nullable = false)
    private Long studentLessonId;

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumn(name = "studentCourseId", nullable = false)
    private StudentCourseDBO studentCourse;

    @ManyToOne(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
    @JoinColumn(name = "lessonId", nullable = false)
    private LessonDBO lesson;

    @Column(name = "percentCompleted", nullable = false)
    private BigDecimal percentCompleted;

}

Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'jpaMappingContext': Invocation of init method failed; nested exception is org.hibernate.MappingException: Foreign key (FKr8cmxbjotnbr91mtv62sakwva:StudentLesson [studentCourseId])) must have same number of columns as the referenced primary key (StudentCourse [studentId,courseId])
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1788) ~[spring-beans-5.3.1.jar:5.3.1]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:609) ~[spring-beans-5.3.1.jar:5.3.1]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:531) ~[spring-beans-5.3.1.jar:5.3.1]
    at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:335) ~[spring-beans-5.3.1.jar:5.3.1]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234) ~[spring-beans-5.3.1.jar:5.3.1]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:333) ~[spring-beans-5.3.1.jar:5.3.1]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208) ~[spring-beans-5.3.1.jar:5.3.1]
    at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveReference(BeanDefinitionValueResolver.java:330) ~[spring-beans-5.3.1.jar:5.3.1]
    ... 28 common frames omitted
Caused by: org.hibernate.MappingException: Foreign key (FKr8cmxbjotnbr91mtv62sakwva:StudentLesson [studentCourseId])) must have same number of columns as the referenced primary key (StudentCourse [studentId,courseId])
    at org.hibernate.mapping.ForeignKey.alignColumns(ForeignKey.java:148) ~[hibernate-core-5.4.23.Final.jar:5.4.23.Final]
    at org.hibernate.mapping.ForeignKey.alignColumns(ForeignKey.java:130) ~[hibernate-core-5.4.23.Final.jar:5.4.23.Final]
    at org.hibernate.boot.internal.InFlightMetadataCollectorImpl.secondPassCompileForeignKeys(InFlightMetadataCollectorImpl.java:1929) ~[hibernate-core-5.4.23.Final.jar:5.4.23.Final]
    at org.hibernate.boot.internal.InFlightMetadataCollectorImpl.secondPassCompileForeignKeys(InFlightMetadataCollectorImpl.java:1845) ~[hibernate-core-5.4.23.Final.jar:5.4.23.Final]
    at org.hibernate.boot.internal.InFlightMetadataCollectorImpl.processSecondPasses(InFlightMetadataCollectorImpl.java:1665) ~[hibernate-core-5.4.23.Final.jar:5.4.23.Final]
    at org.hibernate.boot.model.process.spi.MetadataBuildingProcess.complete(MetadataBuildingProcess.java:286) ~[hibernate-core-5.4.23.Final.jar:5.4.23.Final]
    at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.metadata(EntityManagerFactoryBuilderImpl.java:1224) ~[hibernate-core-5.4.23.Final.jar:5.4.23.Final]
    at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:1255) ~[hibernate-core-5.4.23.Final.jar:5.4.23.Final]
    at org.springframework.orm.jpa.vendor.SpringHibernateJpaPersistenceProvider.createContainerEntityManagerFactory(SpringHibernateJpaPersistenceProvider.java:58) ~[spring-orm-5.3.1.jar:5.3.1]
    at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:365) ~[spring-orm-5.3.1.jar:5.3.1]
    at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.buildNativeEntityManagerFactory(AbstractEntityManagerFactoryBean.java:409) ~[spring-orm-5.3.1.jar:5.3.1]
    at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264) ~[na:na]
    at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128) ~[na:na]
    at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628) ~[na:na]
    at java.base/java.lang.Thread.run(Thread.java:834) ~[na:na]