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Jak usunąć jednostkę z złączeń użyciem JPA i Hibernate

2017-06-13 83 views
8

Mam następujące podmioty:Jak usunąć jednostkę z złączeń użyciem JPA i Hibernate

enter image description here

Chcę usunąć WordSet przez id i nazwa użytkownika z wykorzystaniem JPA.

Oto deklaracje jednostki:

Obsługi

@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); 
    } 
}

Tutaj jest częścią mojego WordSetDao:

@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 działa dobrze, ale usunąć rzuca następujący wyjątek:

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

Również zamiast

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

I "Próbowałem następujące zapytanie:

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)

i działa na mojej bazy danych H2, ale nie działa na MySQL z następującym wyjątkiem:

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] 
    ...

Mam googled o podzapytania i MySQL (one, two), ale nie mógł znaleźć się jak zrobić taką sztuczkę z JPA.

Jak usunąć zestaw słów? Czy coś jest nie tak z mapowaniem mojego obiektu?

Oto mój schemat DB, wygląda poprawne:

enter image description here

Źródło

2017-06-13 solomkinmv

Odpowiedz

7

Istnieją pewne wiele rzeczy, które są złe w tym odwzorowaniu:

  1. Korzystanie EAGER pobierania dla każdego rodzaju kolekcja jest nawet więcej problemu niż obecny problem. Praktycznie pobieranie całego DB z dowolnego zapytania. Switch to LAZY as explained in this article.

  2. Mówiłeś, że pracuje dla H2, ale to nie jest prawda:

    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. Ten typ zapytania nie jest obsługiwana przez 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. przyłącza są zakazane w sprawozdaniach zbiorczych, jak wyjaśniono w Hibernate User Guide.
  5. Teraz, w zależności od liczby pozycji, które chcesz usunąć, lepszym rozwiązaniem może być batch delete, ponieważ możesz zapobiec lost update anomaly.
  6. Masz tutaj wykres połączonych encji, więc usuwanie zbiorcze może i tak nie pomóc, ponieważ nie można usunąć rekordu nadrzędnego bez uprzedniego usunięcia skojarzeń potomnych.

Źródło

2017-06-16 12:09:37

+0

1. Dzięki, wiem o tym. To tylko testowy projekt :) 2. Kiedy powiedziałem, że to działa dla H2, miałem na myśli drugie zapytanie z zagnieżdżonym 'select' 3. Myślałem, że może istnieć jakaś sztuczka do owijania zagnieżdżonego select za pomocą jeszcze jednej instrukcji select, ale mógłbym to zrobić z JPQL. – solomkinmv

+0

Powiedziałeś, że mapowanie ma wiele wad. Co jeszcze jest nie tak, z wyjątkiem pobierania polityki? – solomkinmv

0

java.sql.SQLException: Nie można określić tabelę docelową 'word_set' dla aktualizacji FROM na com .mysql.jdbc.SQLError.createSQLException (SQLError.java:964) ~ [! mysql-łącznik-Java-5.1.40.jar /: 05.01.40]

wyjątek jest spowodowane, ponieważ MySQL ty nie można modyfikować/usuń tę samą tabelę, której używasz w części SELECT. Tutaj udokumentowane to zachowanie https://dev.mysql.com/doc/refman/5.6/en/update.html.Rozwiązania 1) gnieżdżące podkwerendę głębiej w klauzuli FROM lub 2) dołączyć tabelę sobie

Źródło

2017-06-13 21:20:52

+0

Tak, widziałem to. Czy możesz napisać przykład jak zrobić pierwszy lub drugi przypadek używając JPQL (najlepiej drugi)? – solomkinmv

0

Czy próbowałeś regularnie dołączać do usunięcia? Podobne pytanie jest tutaj: Delete with Join in MySQL

... chociaż nie za pośrednictwem JPA, ale istnieje akceptowana odpowiedź, która pokazuje przykład usunięcia opartego na sprzęcie, ale wydaje się, że jest on specyficzny dla MySQL.

Sztuką jest określenie rzeczywistej tabeli w samej klauzuli delete, a nie tylko klauzuli from, gdy istnieją inne tabele odwołujące się za pomocą JOIN.

Nie jestem skonfigurowany do testowania JPA przeciwko mysql w tej chwili. JQL może nie być w stanie tego pomieścić, ale prawdopodobnie można to zrobić za pomocą natywnego zapytania.

Źródło

2017-06-21 17:14:25 slambeth

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