无继承关系的参照完整性约束违规

Question

我正在使用带有数据库H2（内存中）和休眠模式的简单CRUD Spring引导REST应用程序，汽车实体和制造商实体之间存在多对一的关系。

@Entity
@Table(name = "car")
public class Car {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    @JoinColumn(name = "manufacturerId")
    @ManyToOne()
    private Manufacturer manufacturer;
 /// 
}


@Entity
@Table(name = "manufacturer")
public class Manufacturer {

    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    private Long id;

    @OneToMany(mappedBy = "manufacturer")
    private Set<Car> cars;

//
}

当我删除至少与汽车相关的制造商对象时，它显示此异常：

org.springframework.dao.DataIntegrityViolationException: could not execute statement; SQL [n/a]; constraint ["FK3UP36SI6VWEIENGPL21JSRI71: PUBLIC.CAR FOREIGN KEY(MANUFACTURER_ID) REFERENCES PUBLIC.MANUFACTURER(ID) (1)"; SQL statement:
delete from manufacturer where id=? [23503-197]]; nested exception is org.hibernate.exception.ConstraintViolationException: could not execute statement
    at org.springframework.orm.jpa.vendor.HibernateJpaDialect.convertHibernateAccessException(HibernateJpaDialect.java:259) ~[spring-orm-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.orm.jpa.vendor.HibernateJpaDialect.translateExceptionIfPossible(HibernateJpaDialect.java:225) ~[spring-orm-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.orm.jpa.JpaTransactionManager.doCommit(JpaTransactionManager.java:540) ~[spring-orm-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.transaction.support.AbstractPlatformTransactionManager.processCommit(AbstractPlatformTransactionManager.java:746) ~[spring-tx-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.transaction.support.AbstractPlatformTransactionManager.commit(AbstractPlatformTransactionManager.java:714) ~[spring-tx-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.transaction.interceptor.TransactionAspectSupport.commitTransactionAfterReturning(TransactionAspectSupport.java:532) ~[spring-tx-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:304) ~[spring-tx-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:98) ~[spring-tx-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185) ~[spring-aop-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:139) ~[spring-tx-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185) ~[spring-aop-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.data.jpa.repository.support.CrudMethodMetadataPostProcessor$CrudMethodMetadataPopulatingMethodInterceptor.invoke(CrudMethodMetadataPostProcessor.java:135) ~[spring-data-jpa-2.0.6.RELEASE.jar:2.0.6.RELEASE]
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185) ~[spring-aop-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92) ~[spring-aop-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185) ~[spring-aop-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.data.repository.core.support.SurroundingTransactionDetectorMethodInterceptor.invoke(SurroundingTransactionDetectorMethodInterceptor.java:61) ~[spring-data-commons-2.0.6.RELEASE.jar:2.0.6.RELEASE]
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:185) ~[spring-aop-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:212) ~[spring-aop-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at com.sun.proxy.$Proxy111.deleteById(Unknown Source) ~[na:na]
    at com.service.manufacturer.DefaultManufacturerService.delete(DefaultManufacturerService.java:66) ~[classes/:na]
    at com.controller.ManufacturerController.deleteManufacturer(ManufacturerController.java:61) ~[classes/:na]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_171]
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_171]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_171]
    at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_171]
    at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:209) ~[spring-web-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:136) ~[spring-web-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:102) ~[spring-webmvc-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:877) ~[spring-webmvc-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:783) ~[spring-webmvc-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) ~[spring-webmvc-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:991) [spring-webmvc-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:925) [spring-webmvc-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:974) [spring-webmvc-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.web.servlet.FrameworkServlet.doDelete(FrameworkServlet.java:899) [spring-webmvc-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:667) [tomcat-embed-core-8.5.29.jar:8.5.29]
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:851) [spring-webmvc-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:742) [tomcat-embed-core-8.5.29.jar:8.5.29]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) [tomcat-embed-core-8.5.29.jar:8.5.29]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [tomcat-embed-core-8.5.29.jar:8.5.29]

Caused by: org.hibernate.exception.ConstraintViolationException: could not execute statement
    at org.hibernate.exception.internal.SQLStateConversionDelegate.convert(SQLStateConversionDelegate.java:112) ~[hibernate-core-5.2.16.Final.jar:5.2.16.Final]
    at org.hibernate.exception.internal.StandardSQLExceptionConverter.convert(StandardSQLExceptionConverter.java:42) ~[hibernate-core-5.2.16.Final.jar:5.2.16.Final]
    at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:111) ~[hibernate-core-5.2.16.Final.jar:5.2.16.Final]
    at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:97) ~[hibernate-core-5.2.16.Final.jar:5.2.16.Final]
    at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.executeUpdate(ResultSetReturnImpl.java:178) ~[hibernate-core-5.2.16.Final.jar:5.2.16.Final]
    at org.hibernate.engine.jdbc.batch.internal.NonBatchingBatch.addToBatch(NonBatchingBatch.java:45) ~[hibernate-core-5.2.16.Final.jar:5.2.16.Final]
    at org.hibernate.persister.entity.AbstractEntityPersister.delete(AbstractEntityPersister.java:3325) ~[hibernate-core-5.2.16.Final.jar:5.2.16.Final]
    at org.hibernate.persister.entity.AbstractEntityPersister.delete(AbstractEntityPersister.java:3582) ~[hibernate-core-5.2.16.Final.jar:5.2.16.Final]
    at org.hibernate.action.internal.EntityDeleteAction.execute(EntityDeleteAction.java:99) ~[hibernate-core-5.2.16.Final.jar:5.2.16.Final]
    at org.hibernate.engine.spi.ActionQueue.executeActions(ActionQueue.java:600) ~[hibernate-core-5.2.16.Final.jar:5.2.16.Final]
    at org.hibernate.engine.spi.ActionQueue.executeActions(ActionQueue.java:474) ~[hibernate-core-5.2.16.Final.jar:5.2.16.Final]
    at org.hibernate.event.internal.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:337) ~[hibernate-core-5.2.16.Final.jar:5.2.16.Final]
    at org.hibernate.event.internal.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:39) ~[hibernate-core-5.2.16.Final.jar:5.2.16.Final]
    at org.hibernate.internal.SessionImpl.doFlush(SessionImpl.java:1436) ~[hibernate-core-5.2.16.Final.jar:5.2.16.Final]
    at org.hibernate.internal.SessionImpl.managedFlush(SessionImpl.java:493) ~[hibernate-core-5.2.16.Final.jar:5.2.16.Final]
    at org.hibernate.internal.SessionImpl.flushBeforeTransactionCompletion(SessionImpl.java:3206) ~[hibernate-core-5.2.16.Final.jar:5.2.16.Final]
    at org.hibernate.internal.SessionImpl.beforeTransactionCompletion(SessionImpl.java:2412) ~[hibernate-core-5.2.16.Final.jar:5.2.16.Final]
    at org.hibernate.engine.jdbc.internal.JdbcCoordinatorImpl.beforeTransactionCompletion(JdbcCoordinatorImpl.java:473) ~[hibernate-core-5.2.16.Final.jar:5.2.16.Final]
    at org.hibernate.resource.transaction.backend.jdbc.internal.JdbcResourceLocalTransactionCoordinatorImpl.beforeCompletionCallback(JdbcResourceLocalTransactionCoordinatorImpl.java:156) ~[hibernate-core-5.2.16.Final.jar:5.2.16.Final]
    at org.hibernate.resource.transaction.backend.jdbc.internal.JdbcResourceLocalTransactionCoordinatorImpl.access$100(JdbcResourceLocalTransactionCoordinatorImpl.java:38) ~[hibernate-core-5.2.16.Final.jar:5.2.16.Final]
    at org.hibernate.resource.transaction.backend.jdbc.internal.JdbcResourceLocalTransactionCoordinatorImpl$TransactionDriverControlImpl.commit(JdbcResourceLocalTransactionCoordinatorImpl.java:231) ~[hibernate-core-5.2.16.Final.jar:5.2.16.Final]
    at org.hibernate.engine.transaction.internal.TransactionImpl.commit(TransactionImpl.java:68) ~[hibernate-core-5.2.16.Final.jar:5.2.16.Final]
    at org.springframework.orm.jpa.JpaTransactionManager.doCommit(JpaTransactionManager.java:536) ~[spring-orm-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    ... 72 common frames omitted
Caused by: org.h2.jdbc.JdbcSQLException: Referential integrity constraint violation: "FK3UP36SI6VWEIENGPL21JSRI71: PUBLIC.CAR FOREIGN KEY(MANUFACTURER_ID) REFERENCES PUBLIC.MANUFACTURER(ID) (1)"; SQL statement:
delete from manufacturer where id=? [23503-197]
    at org.h2.message.DbException.getJdbcSQLException(DbException.java:357) ~[h2-1.4.197.jar:1.4.197]
    at org.h2.message.DbException.get(DbException.java:179) ~[h2-1.4.197.jar:1.4.197]
    at org.h2.message.DbException.get(DbException.java:155) ~[h2-1.4.197.jar:1.4.197]
    at org.h2.constraint.ConstraintReferential.checkRow(ConstraintReferential.java:386) ~[h2-1.4.197.jar:1.4.197]
    at org.h2.constraint.ConstraintReferential.checkRowRefTable(ConstraintReferential.java:403) ~[h2-1.4.197.jar:1.4.197]
    at org.h2.constraint.ConstraintReferential.checkRow(ConstraintReferential.java:278) ~[h2-1.4.197.jar:1.4.197]
    at org.h2.table.Table.fireConstraints(Table.java:995) ~[h2-1.4.197.jar:1.4.197]
    at org.h2.table.Table.fireAfterRow(Table.java:1013) ~[h2-1.4.197.jar:1.4.197]
    at org.h2.command.dml.Delete.update(Delete.java:108) ~[h2-1.4.197.jar:1.4.197]

如何解决这个问题？

提前致谢！

Answer 1

您可以使用：

@OneToMany(mappedBy = "manufacturer", cascade = CascadeType.REMOVE)
private Set<Car> cars;

然后，当该制造商被删除时，与该制造商相关的所有汽车也将被删除。

如果所有汽车都需要制造商，这是有道理的。 如果没有制造商就可以存在汽车，则可以改用以下代码（将其放入“制造商”实体）：

@PreRemove
private void preRemove() {
   for (Car car: cars) {
      car.setManufacturer(null);
   }
}

这样，属于现已删除的制造商的汽车将仍然存在，但制造商为空。 如果您不想使用@PreRemove批注，则可以在删除制造商服务方法中在其中手动进行迭代。