ChatGPT의 도움을 받았습니다.아래와 같이 시도해보세용~ 

물론 첨부터 깔끔하게 만드는게 best입니다만, 오랜 시스템 일수록 resource들이 엄청 섞여있는 경우가 더 많습니다. (IAM권한 여기저기, 라우팅테이블 일관성 없기, 다 따로노는 NACL등...) 이걸 다 엎을수도 없을테고 선진화 (테라폼 적용) 도 해야하는 경우가 실무에서 꽤 흔하지 않나요?혹시 이럴땐 어떻게 하시는 지요... 제 짧은 생각으로는 일부는 terraform import 로 끌어와서 쓰고 일부는 테라폼으로 제대로 구성해서 쓰고...이렇게도 하나요?

안녕하세요 선생님, 먼저 좋은 강의 감사드립니다.강의를 들으며 갱신 손실 문제를 해결하기 위한 여러 방법들을 학습하며 문득 이런 고민이 생겼습니다. 갱신 손실 문제가 일어날 것 같은 로직(예: 재고 감소)을 구현할 때, 구현 단계에서부터 동시성 제어를 처음부터 고려해야하는가? 고려한다고 했을 때, 트래픽이 얼마나 될지 모르는 상황에서 어떤 방법을 사용할 것인가?이에 대한 제 생각은 이렇습니다. 처음 로직을 작성할 때부터, 갱신 손실 문제가 운영 중에 발생한다면 큰 문제가 될 수 있으므로 반드시 구현 단계에서 부터 고려한다. 갱신 손실 문제가 아예 일어나지 않는 트래픽이더라도 어차피 성능상 손해보는 것은 없을 것이다.트래픽이 얼마가 될지 모르므로 우선 Optimistic Lock을 우선적으로 사용하고, 성능이 안 나오면 Pessimistic Lock 을 사용한다.저는 이렇게 생각했는데, 선생님께서는 위와 같은 상황이라면 어떻게 구현하실 건지 궁금합니다. 또 일단 갱신 손실 문제를 핸들링 하는 상황이라면 Redis나 Named Lock이 아닌 Optimistic Lock, Pessimistic Lock 을 가장 먼저 고려하실 건지도 궁금합니다.읽어주셔서 감사합니다. :)

 안녕하세요 두가지 에러문제로 질문드립니다1번째는 clock 예제를 시작하고 빌드를 하니까 qmake 스텝에서 오류가 나온다고 합니다그 전 강의에서 cmake 가 오류가 적다 말씀하셔서 그 부분을 의심하고 qmake를 cmake로 변경하기위해 구글링 해봤지만 설정을 어떻게 바꾸는지 못찾겠습니다..... 2번째는 include를 하는 곳에서 참조가 안된다하는데 추가로 다른 파일을 다운받아야하나요....? 강의에서 보여주신 qt maintenace에서 다운로드 해야하는것은 체크해서 다운받았는데 참조가 안된다고 하네요....  

controller 단에서 호출하는 mapper 가 오류가 나고 있습니다... 화면에서 crud 시킬때 500에러:Request processing failed; nested exception is java.lang.ClassCastException: java.lang.String cannot be cast to kr.board.entity.MemberUser근본이유:java.lang.ClassCastException: java.lang.String cannot be cast to kr.board.entity.MemberUser kr.board.controller.MemeberController.memRegister(MemeberController.java:118).  controller에서 syso 찍어가며 넘어가야할 값들이 다 들어있는것을 확인했습니다.그런데도 매퍼 접근하려고하면 오류가 나고 있습니다.콘솔에서의 오류:Exception in thread "main" java.lang.NullPointerException at kr.board.controller.BoardRestController.wifiInfoInsert(BoardRestController.java:66)

네

학습하는 분들께 도움이 되고, 더 좋은 답변을 드릴 수 있도록 질문전에 다음을 꼭 확인해주세요.1. 강의 내용과 관련된 질문을 남겨주세요.2. 인프런의 질문 게시판과 자주 하는 질문(링크)을 먼저 확인해주세요.(자주 하는 질문 링크: https://bit.ly/3fX6ygx)3. 질문 잘하기 메뉴얼(링크)을 먼저 읽어주세요.(질문 잘하기 메뉴얼 링크: https://bit.ly/2UfeqCG)질문 시에는 위 내용은 삭제하고 다음 내용을 남겨주세요.=========================================[질문 템플릿]1. 강의 내용과 관련된 질문인가요? (예/아니오)2. 인프런의 질문 게시판과 자주 하는 질문에 없는 내용인가요? (예/아니오)3. 질문 잘하기 메뉴얼을 읽어보셨나요? (예/아니오)[질문 내용]package hello.jdbc.connection; import lombok.extern.slf4j.Slf4j; import org.junit.jupiter.api.Test; import org.springframework.jdbc.datasource.DriverManagerDataSource; import javax.sql.DataSource; import java.sql.Connection; import java.sql.DriverManager; import java.sql.SQLException; import static hello.jdbc.connection.ConnectionConst.*; @Slf4j public class ConnectionTest { @Test void driverManager() throws SQLException { Connection con1 = DriverManager.getConnection(URL, USERNAME, PASSWORD); Connection con2 = DriverManager.getConnection(URL, USERNAME, PASSWORD); log.info("connection={}, class={}", con1, con1.getClass()); log.info("connection={}, class={}", con2, con2.getClass()); } @Test void dataSourceDriverManager() throws SQLException { //DriverManagerDataSource - 항상 새로운 커넥션 획득 DriverManagerDataSource dataSource = new DriverManagerDataSource(URL, USERNAME, PASSWORD); useDataSource(dataSource); } private void useDataSource(DataSource dataSource) throws SQLException { Connection con1 = dataSource.getConnection(); Connection con2 = dataSource.getConnection(); log.info("connection={}, class={}", con1, con1.getClass()); log.info("connection={}, class={}", con2, con2.getClass()); } }실행결과21:19:15.821 [main] INFO hello.jdbc.connection.ConnectionTest -- connection=conn2: url=jdbc:h2:tcp://localhost/~/test user=SA, class=class org.h2.jdbc.JdbcConnection21:19:15.821 [main] INFO hello.jdbc.connection.ConnectionTest -- connection=conn3: url=jdbc:h2:tcp://localhost/~/test user=SA, class=class org.h2.jdbc.JdbcConnection(질문)밑에 내용이 나오지 않은데 왜 그런지 알 수 있을까요?DriverManagerDataSource - Creating new JDBC DriverManager Connection to [jdbc:h2:tcp:..test] DriverManagerDataSource - Creating new JDBC DriverManager Connection to [jdbc:h2:tcp:..test]

그냥 궁금해서 redis-cli에서 "subscribe 1" 을 하고 Redisson 실습 시 락에 대한 메시지가 날아오는 지 궁금해서 해봤더니 아무 내용도 안 오네여? 아예 상관 없는 내용인가여 ㅋㅋㅋ..

http://boj.kr/f1072a98c98a404992c7700849705b0c강의 듣기 전 작성해본 코드입니다.위치랑 시간 업데이트for문으로 상하좌우 탐색 이 때 push 시 시간도 같이 저장시간이 바뀌면 불 업데이트1~3번 반복 하는 도중 탈출 성공하면 return코드 시행 시 메모리 초과가 나오는데 어디에서 초과가 되는지 모르겠습니다.제 생각에는 아마 while 안의 push 부분에서 일어나는 것 같은데 pop을 해주는데도 메모리 초과가 일어날 수 있나요?

학습 관련 질문을 남겨주세요. 어떤 부분이 고민인지, 무엇이 문제인지 상세히 작성하면 더 좋아요!먼저 유사한 질문이 있었는지 검색해 보세요.서로 예의를 지키며 존중하는 문화를 만들어가요.안녕하세요. 강의를 열심히 보고 있는 수강자입니다.다름이 아니라 이번 강의를 보면서 궁금한 점이 있는데요! LocalDateTime을 인자값으로 전달받아 단위테스트하기 좋게 리팩토링하셨는데, 나중에 createOrder를 호출하는 객체의 통합테스트를 진행할때는 시간에 대한 테스트코드를 어떻게 처리하는지 궁금합니다.예를 들어 CafeKioskRunner에서 main 메서드를 통합 테스트한다고 했을 때 시간에 따라 createOrder에서 성공 또는 exception이 발생할 것 같아서 이것에 대한 통합테스트를 어떻게 처리하는지 궁금합니다.감사합니다.

안녕하세요. 우분투로 Vue cli 설치하고 vue create 명령어로 뷰 프로젝트를 만드려고 하는데 자꾸 사진과 같은 오류가 뜨는데 이유를 모르겠어요...ㅠㅠ

안녕하세요Github.com/matbi86/sulgyedokhak 으로 접속하면 404가 뜨며 접속이 되지 않아 여쭤봅니다만일 권한이 필요한 거면 Github 허가 부탁드립니다Github 아이디 : redstar125@naver.comGithub 이름 : henrynam인프런 아이디 : redstar125@naver.com인프런 닉네임 : redstar125

없는데 어떻게 5번지에 자동으로 가나요?

회원 기능 테스트 강의 08:50분에 실행하는 테스트 실행하다 제목과 같은 오류가 발생했습니다ㅠㅠ 커뮤니티에 찾아봐도 몰라서 질문 드립니다. 꼭 좀 도와주시면 감사하겠습니다.MemberRepository 입니다.MemberServiceTest입니다.MemberRepository입니다. 아래는 오류 문입니다antlr.NoViableAltException: unexpected AST node: . at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.logicalExpr(HqlSqlBaseWalker.java:2188) ~[hibernate-core-5.6.15.Final.jar:5.6.15.Final] at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.whereClause(HqlSqlBaseWalker.java:841) ~[hibernate-core-5.6.15.Final.jar:5.6.15.Final] at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.query(HqlSqlBaseWalker.java:635) ~[hibernate-core-5.6.15.Final.jar:5.6.15.Final] at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.selectStatement(HqlSqlBaseWalker.java:339) ~[hibernate-core-5.6.15.Final.jar:5.6.15.Final] at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.statement(HqlSqlBaseWalker.java:287) ~[hibernate-core-5.6.15.Final.jar:5.6.15.Final] at org.hibernate.hql.internal.ast.QueryTranslatorImpl.analyze(QueryTranslatorImpl.java:276) ~[hibernate-core-5.6.15.Final.jar:5.6.15.Final] at org.hibernate.hql.internal.ast.QueryTranslatorImpl.doCompile(QueryTranslatorImpl.java:192) ~[hibernate-core-5.6.15.Final.jar:5.6.15.Final] at org.hibernate.hql.internal.ast.QueryTranslatorImpl.compile(QueryTranslatorImpl.java:144) ~[hibernate-core-5.6.15.Final.jar:5.6.15.Final] at org.hibernate.engine.query.spi.HQLQueryPlan.<init>(HQLQueryPlan.java:112) ~[hibernate-core-5.6.15.Final.jar:5.6.15.Final] at org.hibernate.engine.query.spi.HQLQueryPlan.<init>(HQLQueryPlan.java:73) ~[hibernate-core-5.6.15.Final.jar:5.6.15.Final] at org.hibernate.engine.query.spi.QueryPlanCache.getHQLQueryPlan(QueryPlanCache.java:162) ~[hibernate-core-5.6.15.Final.jar:5.6.15.Final] at org.hibernate.internal.AbstractSharedSessionContract.getQueryPlan(AbstractSharedSessionContract.java:636) ~[hibernate-core-5.6.15.Final.jar:5.6.15.Final] at org.hibernate.internal.AbstractSharedSessionContract.createQuery(AbstractSharedSessionContract.java:748) ~[hibernate-core-5.6.15.Final.jar:5.6.15.Final] at org.hibernate.internal.AbstractSharedSessionContract.createQuery(AbstractSharedSessionContract.java:848) ~[hibernate-core-5.6.15.Final.jar:5.6.15.Final] at org.hibernate.internal.AbstractSharedSessionContract.createQuery(AbstractSharedSessionContract.java:114) ~[hibernate-core-5.6.15.Final.jar:5.6.15.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$SharedEntityManagerInvocationHandler.invoke(SharedEntityManagerCreator.java:315) ~[spring-orm-5.3.26.jar:5.3.26] at com.sun.proxy.$Proxy123.createQuery(Unknown Source) ~[na:na] at jpabook.jpashop.member.MemberRepository.findByName(MemberRepository.java:38) ~[main/:na] at jpabook.jpashop.member.MemberRepository$$FastClassBySpringCGLIB$$cf542431.invoke(<generated>) ~[main/:na] at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218) ~[spring-core-5.3.26.jar:5.3.26] at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:793) ~[spring-aop-5.3.26.jar:5.3.26] at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163) ~[spring-aop-5.3.26.jar:5.3.26] at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763) ~[spring-aop-5.3.26.jar:5.3.26] at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:137) ~[spring-tx-5.3.26.jar:5.3.26] at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.3.26.jar:5.3.26] at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763) ~[spring-aop-5.3.26.jar:5.3.26] at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:708) ~[spring-aop-5.3.26.jar:5.3.26] at jpabook.jpashop.member.MemberRepository$$EnhancerBySpringCGLIB$$22198719.findByName(<generated>) ~[main/:na] at jpabook.jpashop.service.MemberService.validateDUplicateMember(MemberService.java:44) ~[main/:na] at jpabook.jpashop.service.MemberService.join(MemberService.java:33) ~[main/:na] at jpabook.jpashop.service.MemberService$$FastClassBySpringCGLIB$$560b731b.invoke(<generated>) ~[main/:na] at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218) ~[spring-core-5.3.26.jar:5.3.26] at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:793) ~[spring-aop-5.3.26.jar:5.3.26] at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163) ~[spring-aop-5.3.26.jar:5.3.26] at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763) ~[spring-aop-5.3.26.jar:5.3.26] at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:123) ~[spring-tx-5.3.26.jar:5.3.26] at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:388) ~[spring-tx-5.3.26.jar:5.3.26] at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:119) ~[spring-tx-5.3.26.jar:5.3.26] at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.3.26.jar:5.3.26] at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763) ~[spring-aop-5.3.26.jar:5.3.26] at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:708) ~[spring-aop-5.3.26.jar:5.3.26] at jpabook.jpashop.service.MemberService$$EnhancerBySpringCGLIB$$1f95cebf.join(<generated>) ~[main/:na] at jpabook.jpashop.service.MemberServiceTest.MemberSign(MemberServiceTest.java:31) ~[test/: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.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:59) ~[junit-4.13.1.jar:4.13.1] at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12) ~[junit-4.13.1.jar:4.13.1] at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:56) ~[junit-4.13.1.jar:4.13.1] at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17) ~[junit-4.13.1.jar:4.13.1] at org.springframework.test.context.junit4.statements.RunBeforeTestExecutionCallbacks.evaluate(RunBeforeTestExecutionCallbacks.java:74) ~[spring-test-5.3.26.jar:5.3.26] at org.springframework.test.context.junit4.statements.RunAfterTestExecutionCallbacks.evaluate(RunAfterTestExecutionCallbacks.java:84) ~[spring-test-5.3.26.jar:5.3.26] at org.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks.evaluate(RunBeforeTestMethodCallbacks.java:75) ~[spring-test-5.3.26.jar:5.3.26] at org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:86) ~[spring-test-5.3.26.jar:5.3.26] at org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:84) ~[spring-test-5.3.26.jar:5.3.26] at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:366) ~[junit-4.13.1.jar:4.13.1] at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:251) ~[spring-test-5.3.26.jar:5.3.26] at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:97) ~[spring-test-5.3.26.jar:5.3.26] at org.junit.runners.ParentRunner$4.run(ParentRunner.java:331) ~[junit-4.13.1.jar:4.13.1] at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:79) ~[junit-4.13.1.jar:4.13.1] at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:329) ~[junit-4.13.1.jar:4.13.1] at org.junit.runners.ParentRunner.access$100(ParentRunner.java:66) ~[junit-4.13.1.jar:4.13.1] at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:293) ~[junit-4.13.1.jar:4.13.1] at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61) ~[spring-test-5.3.26.jar:5.3.26] at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70) ~[spring-test-5.3.26.jar:5.3.26] at org.junit.runners.ParentRunner$3.evaluate(ParentRunner.java:306) ~[junit-4.13.1.jar:4.13.1] at org.junit.runners.ParentRunner.run(ParentRunner.java:413) ~[junit-4.13.1.jar:4.13.1] at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:190) ~[spring-test-5.3.26.jar:5.3.26] at org.junit.runner.JUnitCore.run(JUnitCore.java:137) ~[junit-4.13.1.jar:4.13.1] at org.junit.runner.JUnitCore.run(JUnitCore.java:115) ~[junit-4.13.1.jar:4.13.1] at org.junit.vintage.engine.execution.RunnerExecutor.execute(RunnerExecutor.java:42) ~[junit-vintage-engine-5.8.2.jar:5.8.2] at org.junit.vintage.engine.VintageTestEngine.executeAllChildren(VintageTestEngine.java:80) ~[junit-vintage-engine-5.8.2.jar:5.8.2] at org.junit.vintage.engine.VintageTestEngine.execute(VintageTestEngine.java:72) ~[junit-vintage-engine-5.8.2.jar:5.8.2] at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:107) ~[na:na] at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:88) ~[na:na] at org.junit.platform.launcher.core.EngineExecutionOrchestrator.lambda$execute$0(EngineExecutionOrchestrator.java:54) ~[na:na] at org.junit.platform.launcher.core.EngineExecutionOrchestrator.withInterceptedStreams(EngineExecutionOrchestrator.java:67) ~[na:na] at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:52) ~[na:na] at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:114) ~[na:na] at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:86) ~[na:na] at org.junit.platform.launcher.core.DefaultLauncherSession$DelegatingLauncher.execute(DefaultLauncherSession.java:86) ~[na:na] at org.junit.platform.launcher.core.SessionPerRequestLauncher.execute(SessionPerRequestLauncher.java:53) ~[na:na] at org.gradle.api.internal.tasks.testing.junitplatform.JUnitPlatformTestClassProcessor$CollectAllTestClassesExecutor.processAllTestClasses(JUnitPlatformTestClassProcessor.java:99) ~[na:na] at org.gradle.api.internal.tasks.testing.junitplatform.JUnitPlatformTestClassProcessor$CollectAllTestClassesExecutor.access$000(JUnitPlatformTestClassProcessor.java:79) ~[na:na] at org.gradle.api.internal.tasks.testing.junitplatform.JUnitPlatformTestClassProcessor.stop(JUnitPlatformTestClassProcessor.java:75) ~[na:na] at org.gradle.api.internal.tasks.testing.SuiteTestClassProcessor.stop(SuiteTestClassProcessor.java:62) ~[na:na] at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na] at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:na] at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na] at java.base/java.lang.reflect.Method.invoke(Method.java:566) ~[na:na] at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:36) ~[na:na] at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:24) ~[na:na] at org.gradle.internal.dispatch.ContextClassLoaderDispatch.dispatch(ContextClassLoaderDispatch.java:33) ~[na:na] at org.gradle.internal.dispatch.ProxyDispatchAdapter$DispatchingInvocationHandler.invoke(ProxyDispatchAdapter.java:94) ~[na:na] at com.sun.proxy.$Proxy2.stop(Unknown Source) ~[na:na] at org.gradle.api.internal.tasks.testing.worker.TestWorker$3.run(TestWorker.java:193) ~[na:na] at org.gradle.api.internal.tasks.testing.worker.TestWorker.executeAndMaintainThreadName(TestWorker.java:129) ~[na:na] at org.gradle.api.internal.tasks.testing.worker.TestWorker.execute(TestWorker.java:100) ~[na:na] at org.gradle.api.internal.tasks.testing.worker.TestWorker.execute(TestWorker.java:60) ~[na:na] at org.gradle.process.internal.worker.child.ActionExecutionWorker.execute(ActionExecutionWorker.java:56) ~[na:na] at org.gradle.process.internal.worker.child.SystemApplicationClassLoaderWorker.call(SystemApplicationClassLoaderWorker.java:113) ~[na:na] at org.gradle.process.internal.worker.child.SystemApplicationClassLoaderWorker.call(SystemApplicationClassLoaderWorker.java:65) ~[na:na] at worker.org.gradle.process.internal.worker.GradleWorkerMain.run(GradleWorkerMain.java:69) ~[gradle-worker.jar:na] at worker.org.gradle.process.internal.worker.GradleWorkerMain.main(GradleWorkerMain.java:74) ~[gradle-worker.jar:na]2023-06-25 19:33:44.563 INFO 23436 --- [ Test worker] p6spy : #1687689224563 | took 0ms | rollback | connection 4| url jdbc:h2:mem:fa852fc9-f2a7-4111-a7ca-8aefa01f2a24;2023-06-25 19:33:44.569 INFO 23436 --- [ Test worker] o.s.t.c.transaction.TransactionContext : Rolled back transaction for test: [DefaultTestContext@15515c51 testClass = MemberServiceTest, testInstance = jpabook.jpashop.service.MemberServiceTest@363ee411, testMethod = MemberSign@MemberServiceTest, testException = org.springframework.dao.InvalidDataAccessApiUsageException: org.hibernate.hql.internal.ast.QuerySyntaxException: unexpected AST node: . near line 1, column 54 [select m from jpabook.jpashop.domain.Member m where m.name]; nested exception is java.lang.IllegalArgumentException: org.hibernate.hql.internal.ast.QuerySyntaxException: unexpected AST node: . near line 1, column 54 [select m from jpabook.jpashop.domain.Member m where m.name], mergedContextConfiguration = [WebMergedContextConfiguration@36a7abe1 testClass = MemberServiceTest, locations = '{}', classes = '{class jpabook.jpashop.JpashopApplication}', contextInitializerClasses = '[]', activeProfiles = '{}', propertySourceLocations = '{}', propertySourceProperties = '{org.springframework.boot.test.context.SpringBootTestContextBootstrapper=true}', contextCustomizers = set[org.springframework.boot.test.autoconfigure.actuate.metrics.MetricsExportContextCustomizerFactory$DisableMetricExportContextCustomizer@463b4ac8, org.springframework.boot.test.autoconfigure.properties.PropertyMappingContextCustomizer@0, org.springframework.boot.test.autoconfigure.web.servlet.WebDriverContextCustomizerFactory$Customizer@66b7550d, org.springframework.boot.test.context.filter.ExcludeFilterContextCustomizer@4212a0c8, org.springframework.boot.test.json.DuplicateJsonObjectContextCustomizerFactory$DuplicateJsonObjectContextCustomizer@476b0ae6, org.springframework.boot.test.mock.mockito.MockitoContextCustomizer@0, org.springframework.boot.test.web.client.TestRestTemplateContextCustomizer@488eb7f2, org.springframework.boot.test.context.SpringBootTestArgs@1, org.springframework.boot.test.context.SpringBootTestWebEnvironment@294e5088], resourceBasePath = 'src/main/webapp', contextLoader = 'org.springframework.boot.test.context.SpringBootContextLoader', parent = [null]], attributes = map['org.springframework.test.context.web.ServletTestExecutionListener.activateListener' -> true, 'org.springframework.test.context.web.ServletTestExecutionListener.populatedRequestContextHolder' -> true, 'org.springframework.test.context.web.ServletTestExecutionListener.resetRequestContextHolder' -> true, 'org.springframework.test.context.event.ApplicationEventsTestExecutionListener.recordApplicationEvents' -> false]]org.hibernate.hql.internal.ast.QuerySyntaxException: unexpected AST node: . near line 1, column 54 [select m from jpabook.jpashop.domain.Member m where m.name]; nested exception is java.lang.IllegalArgumentException: org.hibernate.hql.internal.ast.QuerySyntaxException: unexpected AST node: . near line 1, column 54 [select m from jpabook.jpashop.domain.Member m where m.name]org.springframework.dao.InvalidDataAccessApiUsageException: org.hibernate.hql.internal.ast.QuerySyntaxException: unexpected AST node: . near line 1, column 54 [select m from jpabook.jpashop.domain.Member m where m.name]; nested exception is java.lang.IllegalArgumentException: org.hibernate.hql.internal.ast.QuerySyntaxException: unexpected AST node: . near line 1, column 54 [select m from jpabook.jpashop.domain.Member m where m.name] at app//org.springframework.orm.jpa.EntityManagerFactoryUtils.convertJpaAccessExceptionIfPossible(EntityManagerFactoryUtils.java:374) at app//org.springframework.orm.jpa.vendor.HibernateJpaDialect.translateExceptionIfPossible(HibernateJpaDialect.java:235) at app//org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.translateExceptionIfPossible(AbstractEntityManagerFactoryBean.java:551) at app//org.springframework.dao.support.ChainedPersistenceExceptionTranslator.translateExceptionIfPossible(ChainedPersistenceExceptionTranslator.java:61) at app//org.springframework.dao.support.DataAccessUtils.translateIfNecessary(DataAccessUtils.java:242) at app//org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:152) at app//org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) at app//org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763) at app//org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:708) at app//jpabook.jpashop.member.MemberRepository$$EnhancerBySpringCGLIB$$22198719.findByName(<generated>) at app//jpabook.jpashop.service.MemberService.validateDUplicateMember(MemberService.java:44) at app//jpabook.jpashop.service.MemberService.join(MemberService.java:33) at app//jpabook.jpashop.service.MemberService$$FastClassBySpringCGLIB$$560b731b.invoke(<generated>) at app//org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218) at app//org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:793) at app//org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163) at app//org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763) at app//org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:123) at app//org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:388) at app//org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:119) at app//org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) at app//org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763) at app//org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:708) at app//jpabook.jpashop.service.MemberService$$EnhancerBySpringCGLIB$$1f95cebf.join(<generated>) at app//jpabook.jpashop.service.MemberServiceTest.MemberSign(MemberServiceTest.java:31) at java.base@11/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at java.base@11/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at java.base@11/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.base@11/java.lang.reflect.Method.invoke(Method.java:566) at app//org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:59) at app//org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12) at app//org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:56) at app//org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17) at app//org.springframework.test.context.junit4.statements.RunBeforeTestExecutionCallbacks.evaluate(RunBeforeTestExecutionCallbacks.java:74) at app//org.springframework.test.context.junit4.statements.RunAfterTestExecutionCallbacks.evaluate(RunAfterTestExecutionCallbacks.java:84) at app//org.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks.evaluate(RunBeforeTestMethodCallbacks.java:75) at app//org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:86) at app//org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:84) at app//org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:366) at app//org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:251) at app//org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:97) at app//org.junit.runners.ParentRunner$4.run(ParentRunner.java:331) at app//org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:79) at app//org.junit.runners.ParentRunner.runChildren(ParentRunner.java:329) at app//org.junit.runners.ParentRunner.access$100(ParentRunner.java:66) at app//org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:293) at app//org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61) at app//org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70) at app//org.junit.runners.ParentRunner$3.evaluate(ParentRunner.java:306) at app//org.junit.runners.ParentRunner.run(ParentRunner.java:413) at app//org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:190) at app//org.junit.runner.JUnitCore.run(JUnitCore.java:137) at app//org.junit.runner.JUnitCore.run(JUnitCore.java:115) at app//org.junit.vintage.engine.execution.RunnerExecutor.execute(RunnerExecutor.java:42) at app//org.junit.vintage.engine.VintageTestEngine.executeAllChildren(VintageTestEngine.java:80) at app//org.junit.vintage.engine.VintageTestEngine.execute(VintageTestEngine.java:72) at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:107) at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:88) at org.junit.platform.launcher.core.EngineExecutionOrchestrator.lambda$execute$0(EngineExecutionOrchestrator.java:54) at org.junit.platform.launcher.core.EngineExecutionOrchestrator.withInterceptedStreams(EngineExecutionOrchestrator.java:67) at org.junit.platform.launcher.core.EngineExecutionOrchestrator.execute(EngineExecutionOrchestrator.java:52) at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:114) at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:86) at org.junit.platform.launcher.core.DefaultLauncherSession$DelegatingLauncher.execute(DefaultLauncherSession.java:86) at org.junit.platform.launcher.core.SessionPerRequestLauncher.execute(SessionPerRequestLauncher.java:53) at org.gradle.api.internal.tasks.testing.junitplatform.JUnitPlatformTestClassProcessor$CollectAllTestClassesExecutor.processAllTestClasses(JUnitPlatformTestClassProcessor.java:99) at org.gradle.api.internal.tasks.testing.junitplatform.JUnitPlatformTestClassProcessor$CollectAllTestClassesExecutor.access$000(JUnitPlatformTestClassProcessor.java:79) at org.gradle.api.internal.tasks.testing.junitplatform.JUnitPlatformTestClassProcessor.stop(JUnitPlatformTestClassProcessor.java:75) at org.gradle.api.internal.tasks.testing.SuiteTestClassProcessor.stop(SuiteTestClassProcessor.java:62) at java.base@11/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at java.base@11/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at java.base@11/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.base@11/java.lang.reflect.Method.invoke(Method.java:566) at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:36) at org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:24) at org.gradle.internal.dispatch.ContextClassLoaderDispatch.dispatch(ContextClassLoaderDispatch.java:33) at org.gradle.internal.dispatch.ProxyDispatchAdapter$DispatchingInvocationHandler.invoke(ProxyDispatchAdapter.java:94) at com.sun.proxy.$Proxy2.stop(Unknown Source) at org.gradle.api.internal.tasks.testing.worker.TestWorker$3.run(TestWorker.java:193) at org.gradle.api.internal.tasks.testing.worker.TestWorker.executeAndMaintainThreadName(TestWorker.java:129) at org.gradle.api.internal.tasks.testing.worker.TestWorker.execute(TestWorker.java:100) at org.gradle.api.internal.tasks.testing.worker.TestWorker.execute(TestWorker.java:60) at org.gradle.process.internal.worker.child.ActionExecutionWorker.execute(ActionExecutionWorker.java:56) at org.gradle.process.internal.worker.child.SystemApplicationClassLoaderWorker.call(SystemApplicationClassLoaderWorker.java:113) at org.gradle.process.internal.worker.child.SystemApplicationClassLoaderWorker.call(SystemApplicationClassLoaderWorker.java:65) at app//worker.org.gradle.process.internal.worker.GradleWorkerMain.run(GradleWorkerMain.java:69) at app//worker.org.gradle.process.internal.worker.GradleWorkerMain.main(GradleWorkerMain.java:74)Caused by: java.lang.IllegalArgumentException: org.hibernate.hql.internal.ast.QuerySyntaxException: unexpected AST node: . near line 1, column 54 [select m from jpabook.jpashop.domain.Member m where m.name] at org.hibernate.internal.ExceptionConverterImpl.convert(ExceptionConverterImpl.java:138) at org.hibernate.internal.ExceptionConverterImpl.convert(ExceptionConverterImpl.java:181) at org.hibernate.internal.ExceptionConverterImpl.convert(ExceptionConverterImpl.java:188) at org.hibernate.internal.AbstractSharedSessionContract.createQuery(AbstractSharedSessionContract.java:757) at org.hibernate.internal.AbstractSharedSessionContract.createQuery(AbstractSharedSessionContract.java:848) at org.hibernate.internal.AbstractSharedSessionContract.createQuery(AbstractSharedSessionContract.java:114) at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.base/java.lang.reflect.Method.invoke(Method.java:566) at org.springframework.orm.jpa.SharedEntityManagerCreator$SharedEntityManagerInvocationHandler.invoke(SharedEntityManagerCreator.java:315) at com.sun.proxy.$Proxy123.createQuery(Unknown Source) at jpabook.jpashop.member.MemberRepository.findByName(MemberRepository.java:38) at jpabook.jpashop.member.MemberRepository$$FastClassBySpringCGLIB$$cf542431.invoke(<generated>) at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218) at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:793) at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163) at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763) at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:137) ... 81 moreCaused by: org.hibernate.hql.internal.ast.QuerySyntaxException: unexpected AST node: . near line 1, column 54 [select m from jpabook.jpashop.domain.Member m where m.name] at app//org.hibernate.hql.internal.ast.QuerySyntaxException.convert(QuerySyntaxException.java:74) at app//org.hibernate.hql.internal.ast.ErrorTracker.throwQueryException(ErrorTracker.java:93) at app//org.hibernate.hql.internal.ast.QueryTranslatorImpl.analyze(QueryTranslatorImpl.java:282) at app//org.hibernate.hql.internal.ast.QueryTranslatorImpl.doCompile(QueryTranslatorImpl.java:192) at app//org.hibernate.hql.internal.ast.QueryTranslatorImpl.compile(QueryTranslatorImpl.java:144) at app//org.hibernate.engine.query.spi.HQLQueryPlan.<init>(HQLQueryPlan.java:112) at app//org.hibernate.engine.query.spi.HQLQueryPlan.<init>(HQLQueryPlan.java:73) at app//org.hibernate.engine.query.spi.QueryPlanCache.getHQLQueryPlan(QueryPlanCache.java:162) at app//org.hibernate.internal.AbstractSharedSessionContract.getQueryPlan(AbstractSharedSessionContract.java:636) at app//org.hibernate.internal.AbstractSharedSessionContract.createQuery(AbstractSharedSessionContract.java:748) ... 96 more

const puppeteer = require('puppeteer'); const dotenv = require('dotenv'); dotenv.config(); const crawler = async () => { try { const browser = await puppeteer.launch({ headless: false, args: ['--window-size=1920,1080', '--disable-notifications'] }); const page = await browser.newPage(); await page.setViewport({ width: 1080, height: 1080, }); await page.goto('https://search.naver.com/search.naver?where=nexearch&sm=top_hty&fbm=0&ie=utf8&query=서울+지게차'); await page.waitFor(3000); await page.evaluate(() => { window.scrollBy(0, 1500); document.querySelector('#loc-main-section-root > section > div > div.api_more_wrap > a').click(); }); await page.waitFor(3000); await page.waitFor(3000); await page.evaluate(() => { document.querySelector('#_pcmap_list_scroll_container > ul > li:nth-child(1) > div.qbGlu > div.ouxiq.icT4K > div > div > span > a > span.hClKF').click(); }); await page.waitFor(3000); await page.evaluate(() => { document.querySelector('#_pcmap_list_scroll_container > ul > li:nth-child(1) > div.qbGlu > div.ouxiq.icT4K > div > div > div > div:nth-child(1) > span.RUjqr > a').click(); }); } catch (e) { console.error(e); } }; crawler();  Error: Evaluation failed: TypeError: Cannot read properties of null (reading 'click') at __puppeteer_evaluation_script__:2:151 at ExecutionContext._evaluateInternal (/Users/youssi/Downloads/nodejs-crawler-master/lecture/node_modules/puppeteer/lib/ExecutionContext.js:122:13) at processTicksAndRejections (node:internal/process/task_queues:96:5) at async ExecutionContext.evaluate (/Users/youssi/Downloads/nodejs-crawler-master/lecture/node_modules/puppeteer/lib/ExecutionContext.js:48:12) at async crawler (/Users/youssi/Downloads/nodejs-crawler-master/lecture/index.js:53:5) -- ASYNC -- at ExecutionContext.<anonymous> (/Users/youssi/Downloads/nodejs-crawler-master/lecture/node_modules/puppeteer/lib/helper.js:111:15) at DOMWorld.evaluate (/Users/youssi/Downloads/nodejs-crawler-master/lecture/node_modules/puppeteer/lib/DOMWorld.js:112:20) -- ASYNC -- at Frame.<anonymous> (/Users/youssi/Downloads/nodejs-crawler-master/lecture/node_modules/puppeteer/lib/helper.js:111:15) at Page.evaluate (/Users/youssi/Downloads/nodejs-crawler-master/lecture/node_modules/puppeteer/lib/Page.js:833:43) at Page.<anonymous> (/Users/youssi/Downloads/nodejs-crawler-master/lecture/node_modules/puppeteer/lib/helper.js:112:23) at crawler (/Users/youssi/Downloads/nodejs-crawler-master/lecture/index.js:53:16) 에러가 납니다. 구글 개발자도구에서 select an element~~~ 누르고 나서야 document.querySelector('#_pcmap_list_scroll_container > ul > li:nth-child(1) > div.qbGlu > div.ouxiq.icT4K > div > div > span > a > span.hClKF').click(); });위 소스가 정상적으로 작동을 합니다. 찾아보니 Javascript를 사용하여 브라우저에서 렌더링하는 웹 페이지를 가져오려고 합니다. 즉, Http Request Node를 사용하여 수신하는 초기 응답에 현재 검색 중인 데이터가 포함되지 않습니다. 당신의 데이터는 자바스크립트 안에 로드되어 브라우저에 의해 html에 삽입될 것입니다.이것과 비슷한 거 같습니다. 크롤링이 안되는 것일까요??

강의 잘 듣고 있습니다!블루프린트에서 Array 타입은 STL의 vector로 동적 배열로 구현이 되고, Set과 Map은 STL의 unordered_set, unordered_map으로 해시 테이블로 구현이 되어있다고 이해했습니다.그렇다면 궁금한게 STL의 list나 set, map인 연결 리스트, 이진 탐색 트리는 사용하지 못하나요?못한다면 이유가 뭔지 궁금합니다! 

[질문 템플릿]1. 강의 내용과 관련된 질문인가요? (예2. 인프런의 질문 게시판과 자주 하는 질문에 없는 내용인가요? (예3. 질문 잘하기 메뉴얼을 읽어보셨나요? (예[질문 내용]mv.getModel().put("member",member);에서 mv.getModel()을 해서 model을 불러와 put하는 것까지는 이해가 됩니다.근데 ("member", member)을 하는 이유를 모르겠습니다. member를 넣어서 map을 넣는건가요?그리고 제일 이해가 안되는 것이 "member"부분입니다. 이것은 무슨의미인가요?

안녕하세요강의 자료가 없어서 자료 부탁드립니다.case20plus@gmail.com

DriverManagerDataSource를 사용하면 DriverManager를 통해 직접 DB에 접근해서 Connection을 획득하는 것으로 알고 있습니다.HikariDataSource를 사용하면 ConnectionPool에서 얻어오는 것으로 알고 있습니다.그리고 미리 ConnectionPool 내부의 DriverManager가 직접 DB에 접근해서 Connection을 획득한 후 ConnectionPool에 보관하는 것이 많나요?맞다면 DrvierManagerDataSource나 HikariDataSource 모두 DB로부터 Connection을 직접 획득하는 주체는 DriverManager인거고 획득 방식은 동일한 것이 맞나요?

안녕하세요,강사님. 질문이 있어 글 남깁니다.리트코드 문제에서 작성하신 서브쿼리는 Email을 가지고 GROUP BY를 하고 해당 GROUP BY에서 최소값을 가지는 ID를 조회하는 쿼리인데,그럼 여기서 Email이 중복인지에 대한 조건은 따로 작성할 필요가 없는 것일까요? GROUP BY가 중복은 제외라는 의미도 포함되어 있는걸까요?