Problem with Spring Batch reader from PostgreSQL DB1 to write in PostgreSQL DB2 - postgresql

Question

I have a problem when I want to read data from PostgreSQL Author DB and write to the PostgreSQL Book DB.
I create configurations for the two DB and this is work well.
My problem is in ItemReader.
This is my error:
Encountered an error executing step ETL-file-load in job ETL-Load
error: java.lang.IllegalArgumentException: org.hibernate.hql.internal.ast.QuerySyntaxException: author is not mapped [select id,firstname,lastname from author]
This is my SpringBatchConfig configuration class:
#Configuration
#EnableBatchProcessing
public class SpringBatchConfig {
#Autowired
private EntityManagerFactory entityManagerFactory;
#Bean
public Job job(JobBuilderFactory jobBuilderFactory,
StepBuilderFactory stepBuilderFactory,
ItemReader<Author> itemReader,
ItemProcessor<Author, Book> itemProcessor,
ItemWriter<Book> itemWriter
) {
Step step = stepBuilderFactory.get("ETL-file-load")
.<Author, Book>chunk(100)
.reader(itemReader)
.processor(itemProcessor)
.writer(itemWriter)
.build();
return jobBuilderFactory.get("ETL-Load")
.incrementer(new RunIdIncrementer())
.start(step)
.build();
}
#Bean
public ItemReader<Author> itemReader() throws Exception {
JpaPagingItemReader<Author> reader = new JpaPagingItemReader<Author>();
reader.setEntityManagerFactory(entityManagerFactory);
reader.setQueryString("select id,firstname,lastname from author");
reader.setPageSize(5);
reader.afterPropertiesSet();
return reader;
}
}
This is my Processor class:
#Component
public class Processor implements ItemProcessor<Author, Book> {
#Override
public Book process(Author item) throws Exception {
Book book = new Book();
book.setName(item.getFirstname());
return book;
}
}
This is my DBWriter Class:
#Component
public class DBWriter implements ItemWriter<Book> {
#Autowired
private BookRepository bookRepository;
#Override
public void write(List<? extends Book> book) throws Exception {
System.out.println("Data Saved for Users: " + book);
bookRepository.save(book);
}
}
This is my Author JPA:
#Entity
#Table(name = "author")
public class Author implements Serializable {
private static final long serialVersionUID = -1848119459950659679L;
#Id
#Column(name = "id")
private Long id;
#Column(name = "firstname")
private String firstname;
#Column(name = "lastname")
private String lastname;
This is my application.properties file:
spring.postgresql.datasource.url=jdbc:postgresql://localhost:5432/book_db
spring.postgresql.datasource.username=admin
spring.postgresql.datasource.password=admin
spring.postgresql.datasource.driver-class-name=org.postgresql.Driver
# ------------------------------
# POSTGRESQL DATABASE 2 CONFIGURATION
# ------------------------------
spring.mysql.datasource.url=jdbc:postgresql://localhost:5432/author_db
spring.mysql.datasource.username=admin
spring.mysql.datasource.password=admin
spring.mysql.datasource.driver-class-name=org.postgresql.Driver
This is Auhtor in DB:
This is my full output:
java.lang.IllegalArgumentException: org.hibernate.hql.internal.ast.QuerySyntaxException: author is not mapped [select id,firstname,lastname from author]
at org.hibernate.jpa.spi.AbstractEntityManagerImpl.convert(AbstractEntityManagerImpl.java:1679) ~[hibernate-entitymanager-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.jpa.spi.AbstractEntityManagerImpl.convert(AbstractEntityManagerImpl.java:1602) ~[hibernate-entitymanager-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.jpa.spi.AbstractEntityManagerImpl.convert(AbstractEntityManagerImpl.java:1608) ~[hibernate-entitymanager-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.jpa.spi.AbstractEntityManagerImpl.createQuery(AbstractEntityManagerImpl.java:294) ~[hibernate-entitymanager-5.0.11.Final.jar:5.0.11.Final]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_191]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_191]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_191]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_191]
at org.springframework.orm.jpa.ExtendedEntityManagerCreator$ExtendedEntityManagerInvocationHandler.invoke(ExtendedEntityManagerCreator.java:347) ~[spring-orm-4.3.4.RELEASE.jar:4.3.4.RELEASE]
at com.sun.proxy.$Proxy80.createQuery(Unknown Source) ~[na:na]
at org.springframework.batch.item.database.JpaPagingItemReader.createQuery(JpaPagingItemReader.java:112) ~[spring-batch-infrastructure-3.0.7.RELEASE.jar:3.0.7.RELEASE]
at org.springframework.batch.item.database.JpaPagingItemReader.doReadPage(JpaPagingItemReader.java:203) ~[spring-batch-infrastructure-3.0.7.RELEASE.jar:3.0.7.RELEASE]
at org.springframework.batch.item.database.AbstractPagingItemReader.doRead(AbstractPagingItemReader.java:108) ~[spring-batch-infrastructure-3.0.7.RELEASE.jar:3.0.7.RELEASE]
at org.springframework.batch.item.support.AbstractItemCountingItemStreamItemReader.read(AbstractItemCountingItemStreamItemReader.java:88) ~[spring-batch-infrastructure-3.0.7.RELEASE.jar:3.0.7.RELEASE]
at org.springframework.batch.core.step.item.SimpleChunkProvider.doRead(SimpleChunkProvider.java:91) ~[spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE]
at org.springframework.batch.core.step.item.SimpleChunkProvider.read(SimpleChunkProvider.java:157) ~[spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE]
at org.springframework.batch.core.step.item.SimpleChunkProvider$1.doInIteration(SimpleChunkProvider.java:116) ~[spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE]
at org.springframework.batch.repeat.support.RepeatTemplate.getNextResult(RepeatTemplate.java:374) ~[spring-batch-infrastructure-3.0.7.RELEASE.jar:3.0.7.RELEASE]
at org.springframework.batch.repeat.support.RepeatTemplate.executeInternal(RepeatTemplate.java:215) ~[spring-batch-infrastructure-3.0.7.RELEASE.jar:3.0.7.RELEASE]
at org.springframework.batch.repeat.support.RepeatTemplate.iterate(RepeatTemplate.java:144) ~[spring-batch-infrastructure-3.0.7.RELEASE.jar:3.0.7.RELEASE]
at org.springframework.batch.core.step.item.SimpleChunkProvider.provide(SimpleChunkProvider.java:110) ~[spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE]
at org.springframework.batch.core.step.item.ChunkOrientedTasklet.execute(ChunkOrientedTasklet.java:69) ~[spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE]
at org.springframework.batch.core.step.tasklet.TaskletStep$ChunkTransactionCallback.doInTransaction(TaskletStep.java:406) ~[spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE]
at org.springframework.batch.core.step.tasklet.TaskletStep$ChunkTransactionCallback.doInTransaction(TaskletStep.java:330) ~[spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE]
at org.springframework.transaction.support.TransactionTemplate.execute(TransactionTemplate.java:133) ~[spring-tx-4.3.4.RELEASE.jar:4.3.4.RELEASE]
at org.springframework.batch.core.step.tasklet.TaskletStep$2.doInChunkContext(TaskletStep.java:271) ~[spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE]
at org.springframework.batch.core.scope.context.StepContextRepeatCallback.doInIteration(StepContextRepeatCallback.java:81) ~[spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE]
at org.springframework.batch.repeat.support.RepeatTemplate.getNextResult(RepeatTemplate.java:374) ~[spring-batch-infrastructure-3.0.7.RELEASE.jar:3.0.7.RELEASE]
at org.springframework.batch.repeat.support.RepeatTemplate.executeInternal(RepeatTemplate.java:215) ~[spring-batch-infrastructure-3.0.7.RELEASE.jar:3.0.7.RELEASE]
at org.springframework.batch.repeat.support.RepeatTemplate.iterate(RepeatTemplate.java:144) ~[spring-batch-infrastructure-3.0.7.RELEASE.jar:3.0.7.RELEASE]
at org.springframework.batch.core.step.tasklet.TaskletStep.doExecute(TaskletStep.java:257) ~[spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE]
at org.springframework.batch.core.step.AbstractStep.execute(AbstractStep.java:200) ~[spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE]
at org.springframework.batch.core.job.SimpleStepHandler.handleStep(SimpleStepHandler.java:148) [spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE]
at org.springframework.batch.core.job.AbstractJob.handleStep(AbstractJob.java:392) [spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE]
at org.springframework.batch.core.job.SimpleJob.doExecute(SimpleJob.java:135) [spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE]
at org.springframework.batch.core.job.AbstractJob.execute(AbstractJob.java:306) [spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE]
at org.springframework.batch.core.launch.support.SimpleJobLauncher$1.run(SimpleJobLauncher.java:135) [spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE]
at org.springframework.core.task.SyncTaskExecutor.execute(SyncTaskExecutor.java:50) [spring-core-4.3.4.RELEASE.jar:4.3.4.RELEASE]
at org.springframework.batch.core.launch.support.SimpleJobLauncher.run(SimpleJobLauncher.java:128) [spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_191]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_191]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_191]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_191]
at org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:333) [spring-aop-4.3.4.RELEASE.jar:4.3.4.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint(ReflectiveMethodInvocation.java:190) [spring-aop-4.3.4.RELEASE.jar:4.3.4.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157) [spring-aop-4.3.4.RELEASE.jar:4.3.4.RELEASE]
at org.springframework.batch.core.configuration.annotation.SimpleBatchConfiguration$PassthruAdvice.invoke(SimpleBatchConfiguration.java:127) [spring-batch-core-3.0.7.RELEASE.jar:3.0.7.RELEASE]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179) [spring-aop-4.3.4.RELEASE.jar:4.3.4.RELEASE]
at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:213) [spring-aop-4.3.4.RELEASE.jar:4.3.4.RELEASE]
at com.sun.proxy.$Proxy89.run(Unknown Source) [na:na]
at org.springframework.boot.autoconfigure.batch.JobLauncherCommandLineRunner.execute(JobLauncherCommandLineRunner.java:216) [spring-boot-autoconfigure-1.4.2.RELEASE.jar:1.4.2.RELEASE]
at org.springframework.boot.autoconfigure.batch.JobLauncherCommandLineRunner.executeLocalJobs(JobLauncherCommandLineRunner.java:233) [spring-boot-autoconfigure-1.4.2.RELEASE.jar:1.4.2.RELEASE]
at org.springframework.boot.autoconfigure.batch.JobLauncherCommandLineRunner.launchJobFromProperties(JobLauncherCommandLineRunner.java:125) [spring-boot-autoconfigure-1.4.2.RELEASE.jar:1.4.2.RELEASE]
at org.springframework.boot.autoconfigure.batch.JobLauncherCommandLineRunner.run(JobLauncherCommandLineRunner.java:119) [spring-boot-autoconfigure-1.4.2.RELEASE.jar:1.4.2.RELEASE]
at org.springframework.boot.SpringApplication.callRunner(SpringApplication.java:800) [spring-boot-1.4.2.RELEASE.jar:1.4.2.RELEASE]
at org.springframework.boot.SpringApplication.callRunners(SpringApplication.java:784) [spring-boot-1.4.2.RELEASE.jar:1.4.2.RELEASE]
at org.springframework.boot.SpringApplication.afterRefresh(SpringApplication.java:771) [spring-boot-1.4.2.RELEASE.jar:1.4.2.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:316) [spring-boot-1.4.2.RELEASE.jar:1.4.2.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1186) [spring-boot-1.4.2.RELEASE.jar:1.4.2.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1175) [spring-boot-1.4.2.RELEASE.jar:1.4.2.RELEASE]
at com.roufid.tutorial.Application.main(Application.java:10) [classes/:na]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_191]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_191]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_191]
at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_191]
at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49) [spring-boot-devtools-1.4.2.RELEASE.jar:1.4.2.RELEASE]
Caused by: org.hibernate.hql.internal.ast.QuerySyntaxException: author is not mapped [select id,firstname,lastname from author]
at org.hibernate.hql.internal.ast.QuerySyntaxException.generateQueryException(QuerySyntaxException.java:79) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.QueryException.wrapWithQueryString(QueryException.java:103) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.hql.internal.ast.QueryTranslatorImpl.doCompile(QueryTranslatorImpl.java:218) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.hql.internal.ast.QueryTranslatorImpl.compile(QueryTranslatorImpl.java:142) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.engine.query.spi.HQLQueryPlan.<init>(HQLQueryPlan.java:115) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.engine.query.spi.HQLQueryPlan.<init>(HQLQueryPlan.java:76) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.engine.query.spi.QueryPlanCache.getHQLQueryPlan(QueryPlanCache.java:150) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.internal.AbstractSessionImpl.getHQLQueryPlan(AbstractSessionImpl.java:302) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.internal.AbstractSessionImpl.createQuery(AbstractSessionImpl.java:240) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.internal.SessionImpl.createQuery(SessionImpl.java:1894) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.jpa.spi.AbstractEntityManagerImpl.createQuery(AbstractEntityManagerImpl.java:291) ~[hibernate-entitymanager-5.0.11.Final.jar:5.0.11.Final]
... 62 common frames omitted
Caused by: org.hibernate.hql.internal.ast.QuerySyntaxException: author is not mapped
at org.hibernate.hql.internal.ast.util.SessionFactoryHelper.requireClassPersister(SessionFactoryHelper.java:171) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.hql.internal.ast.tree.FromElementFactory.addFromElement(FromElementFactory.java:91) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.hql.internal.ast.tree.FromClause.addFromElement(FromClause.java:76) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.hql.internal.ast.HqlSqlWalker.createFromElement(HqlSqlWalker.java:321) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.fromElement(HqlSqlBaseWalker.java:3687) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.fromElementList(HqlSqlBaseWalker.java:3576) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.fromClause(HqlSqlBaseWalker.java:716) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.query(HqlSqlBaseWalker.java:572) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.selectStatement(HqlSqlBaseWalker.java:309) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.hql.internal.antlr.HqlSqlBaseWalker.statement(HqlSqlBaseWalker.java:257) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.hql.internal.ast.QueryTranslatorImpl.analyze(QueryTranslatorImpl.java:262) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
at org.hibernate.hql.internal.ast.QueryTranslatorImpl.doCompile(QueryTranslatorImpl.java:190) ~[hibernate-core-5.0.11.Final.jar:5.0.11.Final]
... 70 common frames omitted

Answer 1

Your query is not a valid JPA Query.
This would be a valid query:
select a.id, a.firstname, a.lastname from Author a
BUT you want to select the whole Author so it must be
select a from Author a

Answer 2

I don't know if your problem is solved, but I found the solution.
"select id,firstname,lastname from author"
replace
"from id,firstname,lastname from author"