Do complex native SQL queries in Spring Data JPA work without entity relationship mappings? - jpa

Question

I'm using Spring Boot and Hibernate and have predefined my PostgreSQL DB tables through flyway migrations like this:
CREATE TABLE node (
id uuid NOT NULL,
abbreviation varchar(32),
type varchar(32) NOT NULL,
text varchar(255) NOT NULL,
last_edited_date timestamp,
PRIMARY KEY (id)
);
CREATE TABLE examinationscheme (
id uuid NOT NULL,
name varchar(255) NOT NULL,
category varchar(255) NOT NULL,
author_id uuid NOT NULL,
creation_date timestamp NOT NULL,
last_edited_date timestamp,
root_node_id uuid NOT NULL,
PRIMARY KEY (id),
FOREIGN KEY (author_id) REFERENCES author(id),
FOREIGN KEY (root_node_id) REFERENCES node(id)
);
CREATE TABLE edge (
id uuid NOT NULL,
exs_id uuid NOT NULL,
source_node_id uuid NOT NULL,
target_node_id uuid NOT NULL,
PRIMARY KEY (id),
FOREIGN KEY (exs_id) REFERENCES examinationscheme(id),
FOREIGN KEY (source_node_id) REFERENCES node(id),
FOREIGN KEY (target_node_id) REFERENCES node(id)
);
I have mapped the respective JPA entities to the predefined tables, but left out the relationship mappings such as #OneToOne/#OneToMany etc.
Is it possible to make queries involving JOIN, DISTINCT etc. without the JPA relationship mappings (since the foreign key relations are established in the DB already)?
Will the native SQL query be executed directly on the DB tables without any layers in between?
I would like to something like this:
public interface ExaminationSchemeRepository extends JpaRepository<ExaminationSchemeModel, UUID> {
#Query(value="SELECT DISTINCT n FROM node n, edge e WHERE e.exs_id = ?1 AND (n.id = e.source_node_id OR n.id = e.target_node_id)", nativeQuery = true)
Iterable<Edge> findAllByExaminationSchemeId(UUID id);
}
Of course, I've tried to no avail. Even a simple join such as:
#Query(value="SELECT DISTINCT n FROM node n, edge e", nativeQuery = true)
results in the same stacktrace:
There was an unexpected error (type=Internal Server Error, status=500).
could not execute query; SQL [SELECT n FROM node n, edge e]; nested exception is org.hibernate.exception.SQLGrammarException: could not execute query
org.springframework.dao.InvalidDataAccessResourceUsageException: could not execute query; SQL [SELECT n FROM node n, edge e]; nested exception is org.hibernate.exception.SQLGrammarException: could not execute query
at org.springframework.orm.jpa.vendor.HibernateJpaDialect.convertHibernateAccessException(HibernateJpaDialect.java:259)
at org.springframework.orm.jpa.vendor.HibernateJpaDialect.translateExceptionIfPossible(HibernateJpaDialect.java:233)
at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.translateExceptionIfPossible(AbstractEntityManagerFactoryBean.java:551)
at org.springframework.dao.support.ChainedPersistenceExceptionTranslator.translateExceptionIfPossible(ChainedPersistenceExceptionTranslator.java:61)
at org.springframework.dao.support.DataAccessUtils.translateIfNecessary(DataAccessUtils.java:242)
at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:152)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
at org.springframework.data.jpa.repository.support.CrudMethodMetadataPostProcessor$CrudMethodMetadataPopulatingMethodInterceptor.invoke(CrudMethodMetadataPostProcessor.java:145)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:97)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:215)
at com.sun.proxy.$Proxy123.findAllByExaminationSchemeId(Unknown Source)
at scheme.ExaminationSchemeController.nodesBySchemeId(ExaminationSchemeController.java:60)
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.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:205)
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:150)
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:117)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:895)
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:808)
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1067)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:963)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006)
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:655)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:764)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:227)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)
at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)
at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)
at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.doFilterInternal(WebMvcMetricsFilter.java:96)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201)
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:197)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:97)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:540)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:135)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:78)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:357)
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:382)
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:895)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1732)
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191)
at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.base/java.lang.Thread.run(Thread.java:829)
Caused by: org.hibernate.exception.SQLGrammarException: could not execute query
at org.hibernate.exception.internal.SQLStateConversionDelegate.convert(SQLStateConversionDelegate.java:103)
at org.hibernate.exception.internal.StandardSQLExceptionConverter.convert(StandardSQLExceptionConverter.java:37)
at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:113)
at org.hibernate.loader.Loader.doList(Loader.java:2871)
at org.hibernate.loader.Loader.doList(Loader.java:2850)
at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2682)
at org.hibernate.loader.Loader.list(Loader.java:2677)
at org.hibernate.loader.custom.CustomLoader.list(CustomLoader.java:338)
at org.hibernate.internal.SessionImpl.listCustomQuery(SessionImpl.java:2181)
at org.hibernate.internal.AbstractSharedSessionContract.list(AbstractSharedSessionContract.java:1204)
at org.hibernate.query.internal.NativeQueryImpl.doList(NativeQueryImpl.java:177)
at org.hibernate.query.internal.AbstractProducedQuery.list(AbstractProducedQuery.java:1617)
at org.hibernate.query.Query.getResultList(Query.java:165)
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$DeferredQueryInvocationHandler.invoke(SharedEntityManagerCreator.java:406)
at com.sun.proxy.$Proxy146.getResultList(Unknown Source)
at org.springframework.data.jpa.repository.query.JpaQueryExecution$CollectionExecution.doExecute(JpaQueryExecution.java:128)
at org.springframework.data.jpa.repository.query.JpaQueryExecution.execute(JpaQueryExecution.java:90)
at org.springframework.data.jpa.repository.query.AbstractJpaQuery.doExecute(AbstractJpaQuery.java:155)
at org.springframework.data.jpa.repository.query.AbstractJpaQuery.execute(AbstractJpaQuery.java:143)
at org.springframework.data.repository.core.support.RepositoryMethodInvoker.doInvoke(RepositoryMethodInvoker.java:137)
at org.springframework.data.repository.core.support.RepositoryMethodInvoker.invoke(RepositoryMethodInvoker.java:121)
at org.springframework.data.repository.core.support.QueryExecutorMethodInterceptor.doInvoke(QueryExecutorMethodInterceptor.java:159)
at org.springframework.data.repository.core.support.QueryExecutorMethodInterceptor.invoke(QueryExecutorMethodInterceptor.java:138)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
at org.springframework.data.projection.DefaultMethodInvokingMethodInterceptor.invoke(DefaultMethodInvokingMethodInterceptor.java:80)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:123)
at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:388)
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:119)
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186)
at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:137)
... 62 more
Caused by: org.postgresql.util.PSQLException: The column name id was not found in this ResultSet.
at org.postgresql.jdbc.PgResultSet.findColumn(PgResultSet.java:2865)
at org.postgresql.jdbc.PgResultSet.getObject(PgResultSet.java:2856)
at com.zaxxer.hikari.pool.HikariProxyResultSet.getObject(HikariProxyResultSet.java)
at org.hibernate.type.PostgresUUIDType$PostgresUUIDSqlTypeDescriptor$2.doExtract(PostgresUUIDType.java:89)
at org.hibernate.type.descriptor.sql.BasicExtractor.extract(BasicExtractor.java:47)
at org.hibernate.type.AbstractStandardBasicType.nullSafeGet(AbstractStandardBasicType.java:257)
at org.hibernate.type.AbstractStandardBasicType.nullSafeGet(AbstractStandardBasicType.java:253)
at org.hibernate.type.AbstractStandardBasicType.nullSafeGet(AbstractStandardBasicType.java:243)
at org.hibernate.type.AbstractStandardBasicType.hydrate(AbstractStandardBasicType.java:329)
at org.hibernate.loader.Loader.extractKeysFromResultSet(Loader.java:811)
at org.hibernate.loader.Loader.getRowFromResultSet(Loader.java:735)
at org.hibernate.loader.Loader.getRowsFromResultSet(Loader.java:1047)
at org.hibernate.loader.Loader.processResultSet(Loader.java:998)
at org.hibernate.loader.Loader.doQuery(Loader.java:967)
at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:357)
at org.hibernate.loader.Loader.doList(Loader.java:2868)
... 93 more

Answer 1

Why wouldn't you map the associations if your application needs to run queries on them? It seems like you are making your life harder with no benefits.
That said, you can run any SQL query as long as the columns in the result match the attributes in the entity.
A query like this will work:
#Query(value="SELECT * FROM edge e", nativeQuery = true)
List<Edge> findAll();
The error is telling you that the result from the query doesn't contain a column id. Hibernate doesn't know how to map the field id in Edge to the result of the select.
You can also use aliases:
SELECT DISTINCT e.id as id, e.abbreviation as abbreviation, ... FROM node n, edge e ...
You don't have to map associations if your app doesn't need to know about them (not sure if it's your case). But, Hibernate picks which queries to run based on the mapping and you can have unexpected results or errors if the mapping doesn't match the tables in the db.