java QueryDSL 返回最大值
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时间：2020-11-02 22:36:26 来源:igfitidea点击:
QueryDSL returning max value
提问by Esteban S
I want to return the max value using QueryDSL.
我想使用 QueryDSL 返回最大值。
With this query I return the interval which eventidis equal to idand it is working properly.
使用此查询，我返回eventid等于id并且它正常工作的时间间隔。
QInterval interval = QInterval.interval;
JPAQuery query = new JPAQuery(em);
BooleanExpression checkId = interval.event.eventid.eq(id);
Interval interv = query.from(interval).where(checkId).uniqueResult(interval);
But if I do the same and add this predicate I get an error (I want to return the interval that has and object of the class End that has the max time timestamp:
但是如果我这样做并添加这个谓词，我会得到一个错误（我想返回具有最大时间时间戳的类 End 和对象的间隔：
BooleanExpression getMax = interval.end.timestamp.eq(interval.end.timestamp.max());
Interval interv = query.from(interval).where(getMax).uniqueResult(interval);
I think the problem could be related to interval.end.timestamp.max() because it is a DateTimeExpression.
我认为问题可能与 interval.end.timestamp.max() 相关，因为它是 DateTimeExpression。
The error is Caused by: java.sql.SQLException: Invalid use of group function:
错误是 Caused by: java.sql.SQLException: Invalid use of group function：
org.springframework.orm.jpa.JpaSystemException: could not extract ResultSet; nested exception is org.hibernate.exception.GenericJDBCException: could not extract ResultSet
at org.springframework.orm.jpa.vendor.HibernateJpaDialect.convertHibernateAccessException(HibernateJpaDialect.java:314)
at org.springframework.orm.jpa.vendor.HibernateJpaDialect.translateExceptionIfPossible(HibernateJpaDialect.java:225)
at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.translateExceptionIfPossible(AbstractEntityManagerFactoryBean.java:417)
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.data.jpa.repository.support.CrudMethodMetadataPostProcessor$CrudMethodMetadataPopulatingMethodInterceptor.invoke(CrudMethodMetadataPostProcessor.java:131)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:208)
at com.sun.proxy.$Proxy67.getLastInterval(Unknown Source)
at es.citic.cms.test.dao.AdquisitionDaoTest.testEventPackageDao1(AdquisitionDaoTest.java:105)
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:497)
at org.junit.runners.model.FrameworkMethod.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.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.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:254)
at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:89)
at org.junit.runners.ParentRunner.run(ParentRunner.java:290)
at org.junit.runners.ParentRunner.schedule(ParentRunner.java:71)
at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
at org.junit.runners.ParentRunner.accessQDepartment department = QDepartment.department;
QDepartment d = new QDepartment("d");
queryFactory.selectFrom(department)
.where(department.size.eq(
JPAExpressions.select(d.size.max()).from(d)))
.fetch();
0(ParentRunner.java:58)
at org.junit.runners.ParentRunner.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:193)
at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:50)
at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:459)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:675)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:382)
at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:192)
Caused by: org.hibernate.exception.GenericJDBCException: could not extract ResultSet
at org.hibernate.exception.internal.StandardSQLExceptionConverter.convert(StandardSQLExceptionConverter.java:54)
at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:126)
at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:112)
at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.extract(ResultSetReturnImpl.java:91)
at org.hibernate.loader.Loader.getResultSet(Loader.java:2066)
at org.hibernate.loader.Loader.executeQueryStatement(Loader.java:1863)
at org.hibernate.loader.Loader.executeQueryStatement(Loader.java:1839)
at org.hibernate.loader.Loader.doQuery(Loader.java:910)
at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:355)
at org.hibernate.loader.Loader.doList(Loader.java:2554)
at org.hibernate.loader.Loader.doList(Loader.java:2540)
at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2370)
at org.hibernate.loader.Loader.list(Loader.java:2365)
at org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:497)
at org.hibernate.hql.internal.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:387)
at org.hibernate.engine.query.spi.HQLQueryPlan.performList(HQLQueryPlan.java:236)
at org.hibernate.internal.SessionImpl.list(SessionImpl.java:1300)
at org.hibernate.internal.QueryImpl.list(QueryImpl.java:103)
at org.hibernate.jpa.internal.QueryImpl.list(QueryImpl.java:573)
at org.hibernate.jpa.internal.QueryImpl.getSingleResult(QueryImpl.java:495)
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:497)
at org.springframework.orm.jpa.SharedEntityManagerCreator$DeferredQueryInvocationHandler.invoke(SharedEntityManagerCreator.java:364)
at com.sun.proxy.$Proxy86.getSingleResult(Unknown Source)
at com.mysema.query.jpa.impl.AbstractJPAQuery.getSingleResult(AbstractJPAQuery.java:217)
at com.mysema.query.jpa.impl.AbstractJPAQuery.uniqueResult(AbstractJPAQuery.java:309)
at com.mysema.query.jpa.impl.AbstractJPAQuery.uniqueResult(AbstractJPAQuery.java:301)
at es.citic.cms.model.dao.acq.IntervalRepoImpl.getLastInterval(IntervalRepoImpl.java:43)
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:497)
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.executeMethodOn(RepositoryFactorySupport.java:483)
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.doInvoke(RepositoryFactorySupport.java:458)
at org.springframework.data.repository.core.support.RepositoryFactorySupport$QueryExecutorMethodInterceptor.invoke(RepositoryFactorySupport.java:440)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.data.projection.DefaultMethodInvokingMethodInterceptor.invoke(DefaultMethodInvokingMethodInterceptor.java:61)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.transaction.interceptor.TransactionInterceptor.proceedWithInvocation(TransactionInterceptor.java:99)
at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:281)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:96)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:136)
... 37 more
Caused by: java.sql.SQLException: Invalid use of group function
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:959)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3870)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:3806)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2470)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2617)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2550)
at com.mysql.jdbc.PreparedStatement.executeInternal(PreparedStatement.java:1861)
at com.mysql.jdbc.PreparedStatement.executeQuery(PreparedStatement.java:1962)
at org.apache.commons.dbcp2.DelegatingPreparedStatement.executeQuery(DelegatingPreparedStatement.java:83)
at org.apache.commons.dbcp2.DelegatingPreparedStatement.executeQuery(DelegatingPreparedStatement.java:83)
at org.hibernate.engine.jdbc.internal.ResultSetReturnImpl.extract(ResultSetReturnImpl.java:82)
... 78 more
采纳答案by Rémi Bantos
You could do a sub-query as described in QueryDsl 4.0.6 documentation.
您可以按照 QueryDsl 4.0.6 文档中的说明执行子查询。
See this QueryDsl documentation linkwith an example of query which uses max()function:
请参阅此 QueryDsl文档链接，其中包含使用max()函数的查询示例：
JPAQuery query = new JPAQuery(entityManager);
query.from(qEntity).singleResult(qEntity.id.max());
回答by EpicPandaForce
I couldn't make the QueryDslPredicateExecutorwork with selecting maximum value, I had to use JpaQuerydirectly (QueryDSL 3.2.x)
我无法QueryDslPredicateExecutor通过选择最大值来完成工作，我不得不JpaQuery直接使用（QueryDSL 3.2.x）
query.from(interval).orderBy(interval.end.desc()).fetchFirst();
回答by Micha? Zaborowski
I wanted to get an item with max value... so it looks a bit similar to your problem. Since I've found this answer, then posting my answer likely can help someone.
我想获得一个具有最大值的项目...所以它看起来与您的问题有点相似。既然我找到了这个答案，那么发布我的答案可能会对某人有所帮助。
In SQL I would sort descending, and pick first. Here is something that should work for you:
在 SQL 中，我会降序排序，然后先选择。这里有一些应该对你有用的东西：
##代码##