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如何删除与联接使用JPA和Hibernate实体

solomkinmv 发表于 Java
184
solomkinmv：

我有以下实体：

在这里输入图像描述

我想通过ID和使用JPA的用户的用户名删除WordSet。

下面是实体声明：

用户

@Entity
@Data
@ToString(callSuper = true)
@EqualsAndHashCode(callSuper = true)
@AllArgsConstructor
@NoArgsConstructor
public class User extends AbstractModelClass {

    private String name;
    private String username;
    private String password;
    private String email;

    @ManyToMany(fetch = FetchType.EAGER)
    private Set<Role> roles;
}

UserDictionary

@Entity
@Data
@ToString(callSuper = true)
@EqualsAndHashCode(callSuper = true)
@AllArgsConstructor
@NoArgsConstructor
public class UserDictionary extends AbstractModelClass {

    @OneToMany(fetch = FetchType.EAGER, cascade = CascadeType.ALL, mappedBy = "userDictionary")
    private Set<WordSet> wordSets;

    @OneToOne(cascade = CascadeType.ALL)
    private User user;

    @PrePersist
    private void addDictionaryToWordSets() {
        wordSets.forEach(wordSet -> wordSet.setUserDictionary(this));
    }
}

WordSet

@Entity
@Data
@AllArgsConstructor
@NoArgsConstructor
@EqualsAndHashCode(callSuper = true, exclude = {"studiedWords", "userDictionary"})
@ToString(callSuper = true, exclude = {"studiedWords", "userDictionary"})
public class WordSet extends AbstractModelClass {

    @NotBlank
    private String name;

    @NotBlank
    private String description;

    @ManyToMany(fetch = FetchType.EAGER, cascade = {CascadeType.PERSIST, CascadeType.MERGE, CascadeType.REMOVE})
    private List<StudiedWord> studiedWords;

    @ManyToOne(fetch = FetchType.EAGER)
    private UserDictionary userDictionary;

    public WordSet(String name, String description, List<StudiedWord> studiedWords) {
        this.name = name;
        this.description = description;
        this.studiedWords = studiedWords;
    }

    public WordSet(Long id, String name, String description, List<StudiedWord> studiedWords) {
        super(id);
        this.name = name;
        this.description = description;
        this.studiedWords = studiedWords;
    }

    @PreRemove
    private void removeFromUserDictionary() {
        userDictionary.getWordSets().removeIf(this::equals);
    }
}

这里是我的WordSetDao的一部分：

@Override
public Optional<WordSet> findByIdAndUsername(long id, String username) {
    return findOrEmpty(() -> entityManager.createQuery(
            "SELECT w FROM WordSet w " +
                    "WHERE w.userDictionary.user.username = :username AND w.id = :id", WordSet.class)
                                          .setParameter("id", id)
                                          .setParameter("username", username)
                                          .getSingleResult());
}

@Override
public void deleteByIdAndUsername(long id, String username) {
    entityManager.createQuery(
            "DELETE FROM WordSet w WHERE w.userDictionary.user.username = :username AND w.id = :id")
                 .setParameter("id", id)
                 .setParameter("username", username)
                 .executeUpdate();
}

findByIdAndUsername 工作正常，但删除抛出以下异常：

org.springframework.web.util.NestedServletException: Request processing failed; nested exception is org.springframework.dao.InvalidDataAccessResourceUsageException: could not prepare statement; SQL [/* delete FKs in join table */ delete from word_set_studied_words where (word_set_id) in (select id from word_set where username=? and id=?)]; nested exception is org.hibernate.exception.SQLGrammarException: could not prepare statement

    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:982)
    at org.springframework.web.servlet.FrameworkServlet.doDelete(FrameworkServlet.java:894)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:654)
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846)
    at org.springframework.test.web.servlet.TestDispatcherServlet.service(TestDispatcherServlet.java:65)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)
    at org.springframework.mock.web.MockFilterChain$ServletFilterProxy.doFilter(MockFilterChain.java:167)
    at org.springframework.mock.web.MockFilterChain.doFilter(MockFilterChain.java:134)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:317)
    at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:127)
    at org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:91)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
    at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:115)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
    at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:137)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
    at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:111)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
    at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:169)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
    at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:63)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
    at io.github.solomkinmv.glossary.web.security.auth.JwtTokenAuthenticationProcessingFilter.successfulAuthentication(JwtTokenAuthenticationProcessingFilter.java:58)
    at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:240)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
    at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:121)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
    at org.springframework.security.web.header.HeaderWriterFilter.doFilterInternal(HeaderWriterFilter.java:66)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
    at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:105)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
    at org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal(WebAsyncManagerIntegrationFilter.java:56)
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107)
    at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:331)
    at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:214)
    at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:177)
    at org.springframework.mock.web.MockFilterChain.doFilter(MockFilterChain.java:134)
    at org.springframework.test.web.servlet.MockMvc.perform(MockMvc.java:155)
    at io.github.solomkinmv.glossary.web.controller.WordSetControllerTest.deleteWordSet(WordSetControllerTest.java:236)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
    at org.junit.internal.runners.statements.RunBefores.evaluate(RunBefores.java:26)
    at org.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks.evaluate(RunBeforeTestMethodCallbacks.java:75)
    at org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:86)
    at org.springframework.restdocs.JUnitRestDocumentation$1.evaluate(JUnitRestDocumentation.java:55)
    at org.junit.rules.RunRules.evaluate(RunRules.java:20)
    at org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:84)
    at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:252)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:94)
    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
    at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
    at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70)
    at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:191)
    at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
    at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
    at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:51)
    at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
    at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)
Caused by: org.springframework.dao.InvalidDataAccessResourceUsageException: could not prepare statement; SQL [/* delete FKs in join table */ delete from word_set_studied_words where (word_set_id) in (select id from word_set where username=? and id=?)]; nested exception is org.hibernate.exception.SQLGrammarException: could not prepare statement
    at org.springframework.orm.jpa.vendor.HibernateJpaDialect.convertHibernateAccessException(HibernateJpaDialect.java:261)
    at org.springframework.orm.jpa.vendor.HibernateJpaDialect.translateExceptionIfPossible(HibernateJpaDialect.java:244)
    at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.translateExceptionIfPossible(AbstractEntityManagerFactoryBean.java:491)
    at org.springframework.dao.support.ChainedPersistenceExceptionTranslator.translateExceptionIfPossible(ChainedPersistenceExceptionTranslator.java:59)
    at org.springframework.dao.support.DataAccessUtils.translateIfNecessary(DataAccessUtils.java:213)
    at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:147)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
    at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:656)
    at io.github.solomkinmv.glossary.persistence.dao.impl.WordSetJpaDao$$EnhancerBySpringCGLIB$$48825a47.deleteByIdAndUsername(<generated>)
    at io.github.solomkinmv.glossary.service.domain.impl.WordSetServiceImpl.deleteByIdAndUsername(WordSetServiceImpl.java:128)
    at io.github.solomkinmv.glossary.service.domain.impl.WordSetServiceImpl$$FastClassBySpringCGLIB$$c3da160a.invoke(<generated>)
    at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)
    at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:721)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157)
    at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:99)
    at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:282)
    at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
    at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:656)
    at io.github.solomkinmv.glossary.service.domain.impl.WordSetServiceImpl$$EnhancerBySpringCGLIB$$4b4a0f55.deleteByIdAndUsername(<generated>)
    at io.github.solomkinmv.glossary.web.controller.WordSetController.deleteWordSet(WordSetController.java:79)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:220)
    at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:134)
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:116)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:827)
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:738)
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85)
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:963)
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:897)
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970)
    ... 70 more
Caused by: org.hibernate.exception.SQLGrammarException: could not prepare statement
    at org.hibernate.exception.internal.SQLStateConversionDelegate.convert(SQLStateConversionDelegate.java:106)
    at org.hibernate.exception.internal.StandardSQLExceptionConverter.convert(StandardSQLExceptionConverter.java:42)
    at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:109)
    at org.hibernate.engine.jdbc.internal.StatementPreparerImpl$StatementPreparationTemplate.prepareStatement(StatementPreparerImpl.java:182)
    at org.hibernate.engine.jdbc.internal.StatementPreparerImpl.prepareStatement(StatementPreparerImpl.java:78)
    at org.hibernate.hql.internal.ast.exec.BasicExecutor.doExecute(BasicExecutor.java:78)
    at org.hibernate.hql.internal.ast.exec.DeleteExecutor.execute(DeleteExecutor.java:107)
    at org.hibernate.hql.internal.ast.QueryTranslatorImpl.executeUpdate(QueryTranslatorImpl.java:429)
    at org.hibernate.engine.query.spi.HQLQueryPlan.performExecuteUpdate(HQLQueryPlan.java:374)
    at org.hibernate.internal.SessionImpl.executeUpdate(SessionImpl.java:1348)
    at org.hibernate.internal.QueryImpl.executeUpdate(QueryImpl.java:102)
    at org.hibernate.jpa.internal.QueryImpl.internalExecuteUpdate(QueryImpl.java:405)
    at org.hibernate.jpa.spi.AbstractQueryImpl.executeUpdate(AbstractQueryImpl.java:61)
    at io.github.solomkinmv.glossary.persistence.dao.impl.WordSetJpaDao.deleteByIdAndUsername(WordSetJpaDao.java:50)
    at io.github.solomkinmv.glossary.persistence.dao.impl.WordSetJpaDao$$FastClassBySpringCGLIB$$3577673c.invoke(<generated>)
    at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)
    at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:721)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157)
    at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:136)
    ... 98 more
Caused by: org.h2.jdbc.JdbcSQLException: Column "USERNAME" not found; SQL statement:
/* delete FKs in join table */ delete from word_set_studied_words where (word_set_id) in (select id from word_set where username=? and id=?) [42122-193]
    at org.h2.message.DbException.getJdbcSQLException(DbException.java:345)
    at org.h2.message.DbException.get(DbException.java:179)
    at org.h2.message.DbException.get(DbException.java:155)
    at org.h2.expression.ExpressionColumn.optimize(ExpressionColumn.java:147)
    at org.h2.expression.Comparison.optimize(Comparison.java:178)
    at org.h2.expression.ConditionAndOr.optimize(ConditionAndOr.java:130)
    at org.h2.command.dml.Select.prepare(Select.java:856)
    at org.h2.engine.Session.optimizeQueryExpression(Session.java:233)
    at org.h2.expression.ConditionInSelect.optimize(ConditionInSelect.java:117)
    at org.h2.command.dml.Delete.prepare(Delete.java:131)
    at org.h2.command.Parser.prepareCommand(Parser.java:259)
    at org.h2.engine.Session.prepareLocal(Session.java:561)
    at org.h2.engine.Session.prepareCommand(Session.java:502)
    at org.h2.jdbc.JdbcConnection.prepareCommand(JdbcConnection.java:1203)
    at org.h2.jdbc.JdbcPreparedStatement.<init>(JdbcPreparedStatement.java:73)
    at org.h2.jdbc.JdbcConnection.prepareStatement(JdbcConnection.java:287)
    at sun.reflect.GeneratedMethodAccessor93.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at org.apache.tomcat.jdbc.pool.ProxyConnection.invoke(ProxyConnection.java:126)
    at org.apache.tomcat.jdbc.pool.JdbcInterceptor.invoke(JdbcInterceptor.java:108)
    at org.apache.tomcat.jdbc.pool.DisposableConnectionFacade.invoke(DisposableConnectionFacade.java:81)
    at com.sun.proxy.$Proxy87.prepareStatement(Unknown Source)
    at org.hibernate.engine.jdbc.internal.StatementPreparerImpl$1.doPrepare(StatementPreparerImpl.java:87)
    at org.hibernate.engine.jdbc.internal.StatementPreparerImpl$StatementPreparationTemplate.prepareStatement(StatementPreparerImpl.java:172)
    ... 113 more

此外代替，

DELETE FROM WordSet w WHERE w.userDictionary.user.username = :username AND w.id = :id

我试过下面的查询：

DELETE FROM WordSet w 
WHERE w IN 
    (SELECT ws FROM UserDictionary u 
     JOIN u.wordSets ws 
     WHERE u.user.username = :username AND ws.id = :id)

和它的作品在我的H2数据库，但未能在MySQL具有以下情况除外：

java.sql.SQLException: You can't specify target table 'word_set' for update in FROM clause
    at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:964) ~[mysql-connector-java-5.1.40.jar!/:5.1.40]
    ...

我GOOGLE了有关子查询和MySQL（一个，2），但无法找到如何使这种伎俩与JPA。

那么，如何删除wordset？是不是有什么毛病我实体映射？

这里是我的DB模式，它看起来是正确的：

在这里输入图像描述

弗拉德·米哈尔西亚：

There are some many things that are wrong in this mapping:

  1. Using EAGER fetching for every collection type is even more of an issue than your current problem. You are practically fetching the whole DB with any given query. Switch to LAZY as explained in this article.

  2. You said it works for H2, but that's not true:

    Caused by: org.h2.jdbc.JdbcSQLException: Column "USERNAME" not found; SQL statement:
/* delete FKs in join table */ delete from word_set_studied_words where (word_set_id) in (select id from word_set where username=? and id=?) [42122-193]
at org.h2.message.DbException.getJdbcSQLException(DbException.java:345)

  3. This type of query is not supported by MySQL:

    DELETE FROM WordSet w 
WHERE w IN 
(SELECT ws FROM UserDictionary u 
 JOIN u.wordSets ws 
 WHERE u.user.username = :username AND ws.id = :id)
  4. Joins are prohibited in bulk statements as explained in the Hibernate User Guide.
  5. Now, depending on the number of entries you want to delete, a batch delete might be a better approach since you can prevent lost update anomaly.
  6. 你必须在这里互相连接的实体的图形，所以批量删除可能不会帮助你啦，因为你无法不先删除子关联删除父记录。

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如有侵权，请联系 [email protected] 删除。

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