from절(QTeam.team)과 QMember.member차치

Question

강의 7분16초에서 List result = queryFactory .select( QTeam. team .name , QMember. member .age.avg()) .from(QMember.member) .join( QMember. member .team , QTeam. team ) .groupBy( QTeam. team .name ) .fetch(); 위 코드로 하면 성공하지만 List result = queryFactory .select( QTeam. team .name , QMember. member .age.avg()) .from( QTeam. team ) .join( QMember. member .team , QTeam. team ) .groupBy( QTeam. team .name ) .fetch(); 이렇게 코드를 작성하면 맨아래와 같은 에러가 발생합니다. 하지만 제가 H2에서 위 코드를 SQL로 바꾸면 아래와 같이 된다고 생각해서 select t.NAME , AVG(m.AGE) from Team t join Member m on m.TEAM _ID=t.ID group by t.NAME ; 이렇게 적어서 실행해보니 원하는 결과대로 잘 나오긴하는데 왜 Querydsl에서는 이러한 에러가 발생하는지 궁금합니다. ========================================org.hibernate.hql.internal.ast.InvalidPathException: Invalid path: ' member1.team ' at org.hibernate.hql.internal.ast.util.LiteralProcessor.lookupConstant( LiteralProcessor.java:111 ) ~[ hibernate-core-5.6.10.Final .jar: 5.6.10.Final ] at org.hibernate.hql.internal.ast.tree.DotNode.resolve( DotNode.java:218 ) ~[ hibernate-core-5.6.10.Final .jar: 5.6.10.Final ] at org.hibernate.hql.internal.ast.tree.FromReferenceNode.resolve( FromReferenceNode.java:114 ) ~[ hibernate-core-5.6.10.Final .jar: 5.6.10.Final ] at org.hibernate.hql.internal.ast.tree.FromReferenceNode.resolve( FromReferenceNode.java:109 ) ~[ hibernate-core-5.6.10.Final .jar: 5.6.10.Final ] at org.hibernate.hql.internal.ast.HqlSqlWalker.createFromJoinElement( HqlSqlWalker.java:411 ) ~[ hibernate-core-5.6.10.Final .jar: 5.6.10.Final ] at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.joinElement( HqlSqlBaseWalker.java:4007 ) ~[ hibernate-core-5.6.10.Final .jar: 5.6.10.Final ] at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.fromElement( HqlSqlBaseWalker.java:3793 ) ~[ hibernate-core-5.6.10.Final .jar: 5.6.10.Final ] at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.fromElementList( HqlSqlBaseWalker.java:3671 ) ~[ hibernate-core-5.6.10.Final .jar: 5.6.10.Final ] at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.fromClause( HqlSqlBaseWalker.java:746 ) ~[ hibernate-core-5.6.10.Final .jar: 5.6.10.Final ] at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.query( HqlSqlBaseWalker.java:602 ) ~[ hibernate-core-5.6.10.Final .jar: 5.6.10.Final ] at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.selectStatement( HqlSqlBaseWalker.java:339 ) ~[ hibernate-core-5.6.10.Final .jar: 5.6.10.Final ] at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.statement( HqlSqlBaseWalker.java:287 ) ~[ hibernate-core-5.6.10.Final .jar: 5.6.10.Final ] at org.hibernate.hql.internal.ast.QueryTranslatorImpl.analyze( QueryTranslatorImpl.java:276 ) ~[ hibernate-core-5.6.10.Final .jar: 5.6.10.Final ] at org.hibernate.hql.internal.ast.QueryTranslatorImpl.doCompile( QueryTranslatorImpl.java:192 ) ~[ hibernate-core-5.6.10.Final .jar: 5.6.10.Final ] at org.hibernate.hql.internal.ast.QueryTranslatorImpl.compile( QueryTranslatorImpl.java:144 ) ~[ hibernate-core-5.6.10.Final .jar: 5.6.10.Final ] at org.hibernate.engine.query.spi.HQLQueryPlan.( HQLQueryPlan.java:113 ) ~[ hibernate-core-5.6.10.Final .jar: 5.6.10.Final ] at org.hibernate.engine.query.spi.HQLQueryPlan.( HQLQueryPlan.java:73 ) ~[ hibernate-core-5.6.10.Final .jar: 5.6.10.Final ] at org.hibernate.engine.query.spi.QueryPlanCache.getHQLQueryPlan( QueryPlanCache.java:162 ) ~[ hibernate-core-5.6.10.Final .jar: 5.6.10.Final ] at org.hibernate.internal.AbstractSharedSessionContract.getQueryPlan( AbstractSharedSessionContract.java:636 ) ~[ hibernate-core-5.6.10.Final .jar: 5.6.10.Final ] at org.hibernate.internal.AbstractSharedSessionContract.createQuery( AbstractSharedSessionContract.java:748 ) ~[ hibernate-core-5.6.10.Final .jar: 5.6.10.Final ] at org.hibernate.internal.AbstractSharedSessionContract.createQuery( AbstractSharedSessionContract.java:114 ) ~[ hibernate-core-5.6.10.Final .jar: 5.6.10.Final ] at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na] at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke( NativeMethodAccessorImpl.java:62 ) ~[na:na] at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke( DelegatingMethodAccessorImpl.java:43 ) ~[na:na] at java.base/java.lang.reflect.Method.invoke( Method.java:566 ) ~[na:na] at org.springframework.orm.jpa.SharedEntityManagerCreator$SharedEntityManagerInvocationHandler.invoke( SharedEntityManagerCreator.java:311 ) ~[spring-orm-5.3.22.jar:5.3.22] at com.sun.proxy.$Proxy113.createQuery(Unknown Source) ~[na:na] at com.querydsl.jpa.impl.AbstractJPAQuery.createQuery( AbstractJPAQuery.java:132 ) ~[querydsl-jpa-5.0.0.jar:na] at com.querydsl.jpa.impl.AbstractJPAQuery.createQuery( AbstractJPAQuery.java:125 ) ~[querydsl-jpa-5.0.0.jar:na] at com.querydsl.jpa.impl.AbstractJPAQuery.fetch( AbstractJPAQuery.java:242 ) ~[querydsl-jpa-5.0.0.jar:na] at study.querydsl.QuerydslbasicTest.group ( QuerydslbasicTest.java:215 ) ~[classes/:na] at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na] at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke( NativeMethodAccessorImpl.java:62 ) ~[na:na] at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke( DelegatingMethodAccessorImpl.java:43 ) ~[na:na] at java.base/java.lang.reflect.Method.invoke( Method.java:566 ) ~[na:na] at org.junit.platform.commons.util.ReflectionUtils.invokeMethod( ReflectionUtils.java:725 ) ~[junit-platform-commons-1.8.2.jar:1.8.2] at org.junit.jupiter.engine.execution.MethodInvocation.proceed( MethodInvocation.java:60 ) ~[junit-jupiter-engine-5.8.2.jar:5.8.2] at org.junit.jupiter.engine.execution.InvocationInterceptorChain$ValidatingInvocation.proceed( InvocationInterceptorChain.java:131 ) ~[junit-jupiter-engine-5.8.2.jar:5.8.2] at org.junit.jupiter.engine.extension.TimeoutExtension.intercept( TimeoutExtension.java:149 ) ~[junit-jupiter-engine-5.8.2.jar:5.8.2] at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestableMethod( TimeoutExtension.java:140 ) ~[junit-jupiter-engine-5.8.2.jar:5.8.2] at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestMethod( TimeoutExtension.java:84 ) ~[junit-jupiter-engine-5.8.2.jar:5.8.2] at org.junit.jupiter.engine.execution.ExecutableInvoker$ReflectiveInterceptorCall.lambda$ofVoidMethod$0( ExecutableInvoker.java:115 ) ~[junit-jupiter-engine-5.8.2.jar:5.8.2] at org.junit.jupiter.engine.execution.ExecutableInvoker.lambda$invoke$0( ExecutableInvoker.java:105 ) ~[junit-jupiter-engine-5.8.2.jar:5.8.2] at org.junit.jupiter.engine.execution.InvocationInterceptorChain$InterceptedInvocation.proceed( InvocationInterceptorChain.java:106 ) ~[junit-jupiter-engine-5.8.2.jar:5.8.2] at org.junit.jupiter.engine.execution.InvocationInterceptorChain.proceed( InvocationInterceptorChain.java:64 ) ~[junit-jupiter-engine-5.8.2.jar:5.8.2] at org.junit.jupiter.engine.execution.InvocationInterceptorChain.chainAndInvoke( InvocationInterceptorChain.java:45 ) ~[junit-jupiter-engine-5.8.2.jar:5.8.2] at org.junit.jupiter.engine.execution.InvocationInterceptorChain.invoke( InvocationInterceptorChain.java:37 ) ~[junit-jupiter-engine-5.8.2.jar:5.8.2] at org.junit.jupiter.engine.execution.ExecutableInvoker.invoke( ExecutableInvoker.java:104 ) ~[junit-jupiter-engine-5.8.2.jar:5.8.2] at org.junit.jupiter.engine.execution.ExecutableInvoker.invoke( ExecutableInvoker.java:98 ) ~[junit-jupiter-engine-5.8.2.jar:5.8.2] at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$invokeTestMethod$7( TestMethodTestDescriptor.java:214 ) ~[junit-jupiter-engine-5.8.2.jar:5.8.2] at org.junit.platform.engine.support .hierarchical.ThrowableCollector.execute( ThrowableCollector.java:73 ) ~[junit-platform-engine-1.8.2.jar:1.8.2] at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.invokeTestMethod( TestMethodTestDescriptor.java:210 ) ~[junit-jupiter-engine-5.8.2.jar:5.8.2] at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute( TestMethodTestDescriptor.java:135 ) ~[junit-jupiter-engine-5.8.2.jar:5.8.2] at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute( TestMethodTestDescriptor.java:66 ) ~[junit-jupiter-engine-5.8.2.jar:5.8.2] at org.junit.platform.engine.support .hierarchical.NodeTestTask.lambda$executeRecursively$6( NodeTestTask.java:151 ) ~[junit-platform-engine-1.8.2.jar:1.8.2] at org.junit.platform.engine.support .hierarchical.ThrowableCollector.execute( ThrowableCollector.java:73 ) ~[junit-platform-engine-1.8.2.jar:1.8.2] at org.junit.platform.engine.support .hierarchical.NodeTestTask.lambda$executeRecursively$8( NodeTestTask.java:141 ) ~[junit-platform-engine-1.8.2.jar:1.8.2] at org.junit.platform.engine.support .hierarchical.Node.around( Node.java:137 ) ~[junit-platform-engine-1.8.2.jar:1.8.2] at org.junit.platform.engine.support .hierarchical.NodeTestTask.lambda$executeRecursively$9( NodeTestTask.java:139 ) ~[junit-platform-engine-1.8.2.jar:1.8.2] at org.junit.platform.engine.support .hierarchical.ThrowableCollector.execute( ThrowableCollector.java:73 ) ~[junit-platform-engine-1.8.2.jar:1.8.2] at org.junit.platform.engine.support .hierarchical.NodeTestTask.executeRecursively( NodeTestTask.java:138 ) ~[junit-platform-engine-1.8.2.jar:1.8.2] at org.junit.platform.engine.support .hierarchical.NodeTestTask.execute( NodeTestTask.java:95 ) ~[junit-platform-engine-1.8.2.jar:1.8.2] at java.base/java.util.ArrayList.forEach( ArrayList.java:1541 ) ~[na:na] at org.junit.platform.engine.support .hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll( SameThreadHierarchicalTestExecutorService.java:41 ) ~[junit-platform-engine-1.8.2.jar:1.8.2] at org.junit.platform.engine.support .hierarchical.NodeTestTask.lambda$executeRecursively$6( NodeTestTask.java:155 ) ~[junit-platform-engine-1.8.2.jar:1.8.2] at org.junit.platform.engine.support .hierarchical.ThrowableCollector.execute( ThrowableCollector.java:73 ) ~[junit-platform-engine-1.8.2.jar:1.8.2] at org.junit.platform.engine.support .hierarchical.NodeTestTask.lambda$executeRecursively$8( NodeTestTask.java:141 ) ~[junit-platform-engine-1.8.2.jar:1.8.2] at org.junit.platform.engine.support .hierarchical.Node.around( Node.java:137 ) ~[junit-platform-engine-1.8.2.jar:1.8.2] at org.junit.platform.engine.support .hierarchical.NodeTestTask.lambda$executeRecursively$9( NodeTestTask.java:139 ) ~[junit-platform-engine-1.8.2.jar:1.8.2] at org.junit.platform.engine.support .hierarchical.ThrowableCollector.execute( ThrowableCollector.java:73 ) ~[junit-platform-engine-1.8.2.jar:1.8.2] at org.junit.platform.engine.support .hierarchical.NodeTestTask.executeRecursively( NodeTestTask.java:138 ) ~[junit-platform-engine-1.8.2.jar:1.8.2] at org.junit.platform.engine.support .hierarchical.NodeTestTask.execute( NodeTestTask.java:95 ) ~[junit-platform-engine-1.8.2.jar:1.8.2] at java.base/java.util.ArrayList.forEach( ArrayList.java:1541 ) ~[na:na]

김영한 · Answer

안녕하세요. aws5624님 JPQL은 SQL과 일부 다른점이 있습니다. 여기서 다른 점은 객체 그래프를 탐색하는 방식으로 쿼리를 작성해야 합니다. from절부터 시작이기 때문에 성공하는 코드는 from절에서 member가 나왔고 join에서 member와 연관된 team을 찾았습니다. 반면에 실패하는 코드는 from절에서 team을 선택했습니다. 따라서 조인을 할 때 team부터 시작을 해야 합니다. 그런데 join에 보면 member부터 시작하고 있습니다. 따라서 잘못된 경로라고 표시됩니다. 감사합니다.