如何使用 spring jpa 执行 JOIN 查询？

【问题标题】：How to perform a JOIN query with spring jpa?如何使用 spring jpa 执行 JOIN 查询？
【发布时间】：2019-02-08 14:51:33
【问题描述】：

我正在尝试使用 Spring jpa 在这两个表之间设置连接查询： https://image.noelshack.com/fichiers/2019/06/5/1549636975-relation.png

我已经尝试在我的学生存储库中这样做：

  @Query("SELECT id FROM Student JOIN Offer ON Offer.id=Student.school.id")

但是当我尝试执行我的代码时它总是给我一个错误

这是我的学生实体：

    package EIC.com.example.Backend.Entity;
    import org.hibernate.annotations.Cascade;
    import javax.persistence.*;
    @Entity
    @Table(name = "etudiant")

    public class Student {
        @Id
        @Column(name="Apogee")
        private int id;
        @Column(name="Prenom")
        private String first_name;
        @Column(name="Nom")
        private String last_name;
        @Column(name="Classement")
        private int rank;
        @Column(name="Filiere")
        private String speciality;
        @ManyToOne
        @JoinColumn(name = "Offre")
        private Offer school;
        /* Getters Setters Constructors */
     }

还有我的报价实体：

    package EIC.com.example.Backend.Entity;

    import javax.persistence.*;
    import java.util.ArrayList;
    import java.util.Date;
    import java.util.List;


    @Entity
    @Table(name = "offre")

    public class Offer {
        @Id
        @Column(name = "ID_OFFRE")
        private int id;
        @Column(name = "Type")
        private int type; // 0 for DD 1 for MOBILITY
        @Column(name = "Etablissement")
        private String school;
        @Column(name = "Filiere_Concerne")
        private String target;
        @Column(name = "Nb_place")
        private int seats;
        @Column(name = "Delai")
        private Date limit;
        @OneToMany
        @JoinColumn(name = "Offre")
        private List<Student> students=new ArrayList<>();
        /* GETTERS SETTERS CONSTRUCTORS */
     }

堆栈跟踪：

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'studentController': Unsatisfied dependency expressed through field 'studentRep'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'studentRep': Invocation of init method failed; nested exception is java.lang.IllegalArgumentException: Validation failed for query for method public abstract java.util.List EIC.com.example.Backend.Repository.StudentRep.test()!
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:596) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:90) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessProperties(AutowiredAnnotationBeanPostProcessor.java:374) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1378) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:575) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:498) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:320) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:318) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:846) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:863) ~[spring-context-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:546) ~[spring-context-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:142) ~[spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE]
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:775) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE]
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:316) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1260) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1248) [spring-boot-2.1.2.RELEASE.jar:2.1.2.RELEASE]
at EIC.com.example.Backend.BackendApplication.main(BackendApplication.java:10) [classes/:na]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_191]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_191]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_191]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_191]
at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49) [spring-boot-devtools-2.1.2.RELEASE.jar:2.1.2.RELEASE]
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'studentRep': Invocation of init method failed; nested exception is java.lang.IllegalArgumentException: Validation failed for query for method public abstract java.util.List EIC.com.example.Backend.Repository.StudentRep.test()!
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1745) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:576) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:498) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:320) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:318) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:277) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1244) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1164) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:593) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE]
... 24 common frames omitted
Caused by: java.lang.IllegalArgumentException: Validation failed for query for method public abstract java.util.List EIC.com.example.Backend.Repository.StudentRep.test()!
at org.springframework.data.jpa.repository.query.SimpleJpaQuery.validateQuery(SimpleJpaQuery.java:93) ~[spring-data-jpa-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.data.jpa.repository.query.SimpleJpaQuery.<init>(SimpleJpaQuery.java:63) ~[spring-data-jpa-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.data.jpa.repository.query.JpaQueryFactory.fromMethodWithQueryString(JpaQueryFactory.java:76) ~[spring-data-jpa-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.data.jpa.repository.query.JpaQueryFactory.fromQueryAnnotation(JpaQueryFactory.java:56) ~[spring-data-jpa-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.data.jpa.repository.query.JpaQueryLookupStrategy$DeclaredQueryLookupStrategy.resolveQuery(JpaQueryLookupStrategy.java:139) ~[spring-data-jpa-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.data.jpa.repository.query.JpaQueryLookupStrategy$CreateIfNotFoundQueryLookupStrategy.resolveQuery(JpaQueryLookupStrategy.java:206) ~[spring-data-jpa-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.data.jpa.repository.query.JpaQueryLookupStrategy$AbstractQueryLookupStrategy.resolveQuery(JpaQueryLookupStrategy.java:79) ~[spring-data-jpa-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.lookupQuery(RepositoryFactorySupport.java:566) ~[spring-data-commons-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.lambda$mapMethodsToQuery$1(RepositoryFactorySupport.java:559) ~[spring-data-commons-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:193) ~[na:1.8.0_191]
at java.util.Iterator.forEachRemaining(Iterator.java:116) ~[na:1.8.0_191]
at java.util.Collections$UnmodifiableCollection$1.forEachRemaining(Collections.java:1049) ~[na:1.8.0_191]
at java.util.Spliterators$IteratorSpliterator.forEachRemaining(Spliterators.java:1801) ~[na:1.8.0_191]
at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:481) ~[na:1.8.0_191]
at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:471) ~[na:1.8.0_191]
at java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:708) ~[na:1.8.0_191]
at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234) ~[na:1.8.0_191]
at java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:499) ~[na:1.8.0_191]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.mapMethodsToQuery(RepositoryFactorySupport.java:561) ~[spring-data-commons-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.lambda$new$0(RepositoryFactorySupport.java:551) ~[spring-data-commons-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at java.util.Optional.map(Optional.java:215) ~[na:1.8.0_191]
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.<init>(RepositoryFactorySupport.java:551) ~[spring-data-commons-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.data.repository.core.support.RepositoryFactorySupport.getRepository(RepositoryFactorySupport.java:324) ~[spring-data-commons-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.data.repository.core.support.RepositoryFactoryBeanSupport.lambda$afterPropertiesSet$5(RepositoryFactoryBeanSupport.java:297) ~[spring-data-commons-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.data.util.Lazy.getNullable(Lazy.java:211) ~[spring-data-commons-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.data.util.Lazy.get(Lazy.java:94) ~[spring-data-commons-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.data.repository.core.support.RepositoryFactoryBeanSupport.afterPropertiesSet(RepositoryFactoryBeanSupport.java:300) ~[spring-data-commons-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.data.jpa.repository.support.JpaRepositoryFactoryBean.afterPropertiesSet(JpaRepositoryFactoryBean.java:119) ~[spring-data-jpa-2.1.4.RELEASE.jar:2.1.4.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1804) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1741) ~[spring-beans-5.1.4.RELEASE.jar:5.1.4.RELEASE]
... 34 common frames omitted
Caused by: java.lang.IllegalArgumentException: org.hibernate.QueryException: No data type for node: org.hibernate.hql.internal.ast.tree.IdentNode 
\-[IDENT] IdentNode: 'id' {originalText=id}
[SELECT id From EIC.com.example.Backend.Entity.Student JOIN EIC.com.example.Backend.Entity.Offer ON Student.school.id=Offer.id]
at org.hibernate.internal.ExceptionConverterImpl.convert(ExceptionConverterImpl.java:138) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.internal.ExceptionConverterImpl.convert(ExceptionConverterImpl.java:181) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.internal.ExceptionConverterImpl.convert(ExceptionConverterImpl.java:188) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.internal.AbstractSharedSessionContract.createQuery(AbstractSharedSessionContract.java:713) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.internal.AbstractSessionImpl.createQuery(AbstractSessionImpl.java:23) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_191]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_191]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_191]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_191]
at org.springframework.orm.jpa.ExtendedEntityManagerCreator$ExtendedEntityManagerInvocationHandler.invoke(ExtendedEntityManagerCreator.java:350) ~[spring-orm-5.1.4.RELEASE.jar:5.1.4.RELEASE]
at com.sun.proxy.$Proxy97.createQuery(Unknown Source) ~[na:na]
at org.springframework.data.jpa.repository.query.SimpleJpaQuery.validateQuery(SimpleJpaQuery.java:87) ~[spring-data-jpa-2.1.4.RELEASE.jar:2.1.4.RELEASE]
... 63 common frames omitted
Caused by: org.hibernate.QueryException: No data type for node: org.hibernate.hql.internal.ast.tree.IdentNode 
\-[IDENT] IdentNode: 'id' {originalText=id}
[SELECT id From EIC.com.example.Backend.Entity.Student JOIN EIC.com.example.Backend.Entity.Offer ON Student.school.id=Offer.id]
at org.hibernate.QueryException.generateQueryException(QueryException.java:120) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.QueryException.wrapWithQueryString(QueryException.java:103) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.hql.internal.ast.QueryTranslatorImpl.doCompile(QueryTranslatorImpl.java:219) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.hql.internal.ast.QueryTranslatorImpl.compile(QueryTranslatorImpl.java:143) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.engine.query.spi.HQLQueryPlan.<init>(HQLQueryPlan.java:119) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.engine.query.spi.HQLQueryPlan.<init>(HQLQueryPlan.java:80) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.engine.query.spi.QueryPlanCache.getHQLQueryPlan(QueryPlanCache.java:153) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.internal.AbstractSharedSessionContract.getQueryPlan(AbstractSharedSessionContract.java:595) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.internal.AbstractSharedSessionContract.createQuery(AbstractSharedSessionContract.java:704) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
... 71 common frames omitted
Caused by: org.hibernate.QueryException: No data type for node: org.hibernate.hql.internal.ast.tree.IdentNode 
\-[IDENT] IdentNode: 'id' {originalText=id}

at org.hibernate.hql.internal.ast.tree.SelectClause.initializeExplicitSelectClause(SelectClause.java:161) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.hql.internal.ast.HqlSqlWalker.useSelectClause(HqlSqlWalker.java:1018) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.hql.internal.ast.HqlSqlWalker.processQuery(HqlSqlWalker.java:786) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.query(HqlSqlBaseWalker.java:677) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.selectStatement(HqlSqlBaseWalker.java:313) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.statement(HqlSqlBaseWalker.java:261) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.hql.internal.ast.QueryTranslatorImpl.analyze(QueryTranslatorImpl.java:271) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
at org.hibernate.hql.internal.ast.QueryTranslatorImpl.doCompile(QueryTranslatorImpl.java:191) ~[hibernate-core-5.3.7.Final.jar:5.3.7.Final]
... 77 common frames omitted


Process finished with exit code 0

【问题讨论】：

  • 请添加错误的stacktrace。
  • 始终查看堆栈跟踪中的最后一个“原因”：节点没有数据类型：org.hibernate.hql.internal.ast.tree.IdentNode \-[IDENT] IdentNode: 'id ' {originalText=id}
  • 对 JPA 文档的简单回顾会告诉您 JPQL 跨 RELATIONS 连接。 Student JOIN Offer 不会跨关系加入。

标签： java spring spring-boot jpa


【解决方案1】：

试试下面的。这样一来，大学就迫不及待地加载了。这仅在您只加载 1 所大学的情况下才有用。例如，如果您对大学进行此操作，您将加载所有学生及其属性的列表。现在，当您通过 id 加载学生时，它也会获取大学

    @ManyToOne(fetch = FetchType.EAGER)
    @JoinColumn(name = "Offre")
    private Offer school;

【讨论】：

  • org.springframework.beans.factory.UnsatisfiedDependencyException：创建名为“studentController”的bean时出错：通过字段“studentRep”表达的依赖关系不满足；嵌套异常是 org.springframework.beans.factory.BeanCreationException：创建名为“studentRep”的 bean 时出错：调用 init 方法失败；嵌套异常是 java.lang.IllegalArgumentException: Validation failed for query for public abstract java.util.List EIC.com.example.Backend.Repository.StudentRep.test()！
  • 请在上面的问题中发布此堆栈跟踪
  • 如果你要定义查询，你必须通过在 @Query 注释中设置 (nativeQuery = true) 来告诉 jpa
【解决方案2】：

在您的学生实体中添加字段 offerId

@Column(name = "OfferId")
private int offerId;

然后改成

@ManyToOne
@JoinColumn(name = "OfferId")
private Offer school;

在您的优惠实体中，更改为

@OneToMany(fetch = FetchType.LAZY, mappedBy = "school")
private List<Student> students = new ArrayList<>();

然后试试这个@Query

@Query("SELECT id FROM Student std JOIN Offer off ON off.id = std.offerId")

【讨论】：

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