我有一个实体:
@Entity
public class Student {
@GeneratedValue(strategy = GenerationType.AUTO)
@Id
private long id;
@OneToMany
private Set<Course> courses;
}
当我尝试持久保存此类型的第一个实体时,它可以正常工作,但是当我尝试使用与已存储实体相同的路线保存新学生时,它会失败。这是错误:
insert into student_courses (student, courses) values (?, ?) [23505-172]]; nested exception is org.hibernate.exception.ConstraintViolationException: could not execute statement] with root cause
org.h2.jdbc.JdbcSQLException: Unique index or primary key violation: "UK_1DBE7B943AC44E1B841DA2688EB_INDEX_5 ON PUBLIC.STUDENT_COURSES(COURSES)"; SQL statement:
insert into student_courses (student, courses) values (?, ?) [23505-172]
at org.h2.message.DbException.getJdbcSQLException(DbException.java:329)
at org.h2.message.DbException.get(DbException.java:169)
at org.h2.message.DbException.get(DbException.java:146)
at org.h2.index.BaseIndex.getDuplicateKeyException(BaseIndex.java:83)
at org.h2.index.TreeIndex.add(TreeIndex.java:65)
at org.h2.table.RegularTable.addRow(RegularTable.java:124)
at org.h2.command.dml.Insert.insertRows(Insert.java:126)
at org.h2.command.dml.Insert.update(Insert.java:86)
at org.h2.command.CommandContainer.update(CommandContainer.java:79)
at org.h2.command.Command.executeUpdate(Command.java:235)
at org.h2.jdbc.JdbcPreparedStatement.executeUpdateInternal(JdbcPreparedStatement.java:154)
at org.h2.jdbc.JdbcPreparedStatement.executeUpdate(JdbcPreparedStatement.java:140)
at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.executeUpdate(ResultSetReturnImpl.java:133)
at org.hibernate.engine.jdbc.batch.internal.NonBatchingBatch.addToBatch(NonBatchingBatch.java:58)
at org.hibernate.persister.collection.AbstractCollectionPersister.recreate(AbstractCollectionPersister.java:1256)
at org.hibernate.action.internal.CollectionRecreateAction.execute(CollectionRecreateAction.java:58)
at org.hibernate.engine.spi.ActionQueue.execute(ActionQueue.java:364)
at org.hibernate.engine.spi.ActionQueue.executeActions(ActionQueue.java:356)
at org.hibernate.engine.spi.ActionQueue.executeActions(ActionQueue.java:281)
at org.hibernate.event.internal.AbstractFlushingEventListener.performExecutions(AbstractFlushingEventListener.java:328)
at org.hibernate.event.internal.DefaultFlushEventListener.onFlush(DefaultFlushEventListener.java:52)
at org.hibernate.internal.SessionImpl.flush(SessionImpl.java:1234)
at org.hibernate.internal.SessionImpl.managedFlush(SessionImpl.java:404)
at org.hibernate.engine.transaction.internal.jdbc.JdbcTransaction.beforeTransactionCommit(JdbcTransaction.java:101)
at org.hibernate.engine.transaction.spi.AbstractTransactionImpl.commit(AbstractTransactionImpl.java:175)
at org.hibernate.ejb.TransactionImpl.commit(TransactionImpl.java:75)
at org.springframework.orm.jpa.JpaTransactionManager.doCommit(JpaTransactionManager.java:515)
at org.springframework.transaction.support.AbstractPlatformTransactionManager.processCommit(AbstractPlatformTransactionManager.java:757)
at org.springframework.transaction.support.AbstractPlatformTransactionManager.commit(AbstractPlatformTransactionManager.java:726)
at org.springframework.transaction.interceptor.TransactionAspectSupport.commitTransactionAfterReturning(TransactionAspectSupport.java:478)
at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:272)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:95)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:158)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.data.jpa.repository.support.LockModeRepositoryPostProcessor$LockModePopulatingMethodIntercceptor.invoke(LockModeRepositoryPostProcessor.java:92)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:207)
at com.sun.proxy.$Proxy45.save(Unknown Source)
at students.StudentController.createRandomShiur(ShiurimController.java:66)
at shiurim.StudentController.getStudents(StudentController.java:26)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:597)
at org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:220)
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:133)
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:104)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandleMethod(RequestMappingHandlerAdapter.java:746)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:687)
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:83)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:925)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:856)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:946)
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:837)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:621)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:822)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:728)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:77)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:108)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:222)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:123)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
at org.apache.catalina.valves.RemoteIpValve.invoke(RemoteIpValve.java:680)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:171)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1023)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1686)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:895)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:918)
at java.lang.Thread.run(Thread.java:695)
我使用Spring Data JPA,Hibernate和H2作为数据库。
应用程序创建了自己的数据库表:
HibernateJpaVendorAdapter hibernateJpaVendorAdapter = new HibernateJpaVendorAdapter();
hibernateJpaVendorAdapter.setShowSql(false);
hibernateJpaVendorAdapter.setGenerateDdl(true);
hibernateJpaVendorAdapter.setDatabase(Database.H2);
那么,为什么会有一个独特的约束?
更新
我看到Hibernate添加了约束:
Hibernate: alter table student_courses add constraint UK_a8c48f36df374f1293c46699c83 unique (courses)
如何告诉Hibernate不要创建它?
谢谢!
答案 0 :(得分:11)
由于违规发生在STUDENT_COURSES
表中,看起来你似乎试图坚持两次相同的关系。您映射了一个Set
,它告诉Hibernate这些关系必须发生不超过一次。检查生成的DDL以获取COURSE_ID,STUDENT_ID上的唯一索引。
原因可能是您的程序逻辑中存在缺陷(例如,在equals
添加到集合中Course
之后修改与equals
相关的字段或Course
{ {1}}实体。
如果Student
可以多次参加Course
(例如第一次失败),您必须自己决定(您的客户在现实世界中,因为这是商业决策)
答案 1 :(得分:0)
您必须使用GenerationType.TABLE
代替GenerationType.AUTO
。这样,jpa使用序列表进行id赋值,您可能永远不需要生成序列或自动递增值或触发器,从而降低可移植性。
答案 2 :(得分:0)
这不是Sequence / JPA /hibern的问题。根据您的日志,在student_courses上发生错误
insert into student_courses
UK_1DBE7B943AC44E1B841DA2688EB_INDEX_5
好像,你在student_course表中有课程的unquie约束。删除那个unquie约束/你可能需要添加学生和课程的复合,以获得不仅仅是课程的不受约束。
答案 3 :(得分:0)
实际上有
@OneToMany
关系时,您可能会设置@ManyToMany
。
假设Course
没有自动生成的ID,那么当第二个学生添加具有相同名称的课程时,就会出现问题。
由于这是一对多关系,因此将使用相同的唯一受限ID创建新课程