How to connect postgresql in hibernate.cfg.xml

Question

I am trying to insert some data into postgresql through hibernate. However, there are not much tutorial about configurate hibernate with postgresql (I know, it should be similar to mysql =))

src/main/resources/hibernate.cfg.xml

<hibernate-configuration>
<session-factory>
<property name="connection.driver_class">org.postgresql.Driver</property>
<property name="connection.url">jdbc:postgresql://127.0.0.1:5432/myDatabase</property>
<property name="connection.username">myUser</property>
<property name="connection.password">myPassword</property>

<!-- JDBC connection pool (use the build-in) -->
<property name="connection.pool_size">1</property>
<!-- SQL dialect -->
<property name="dialect">org.hibernate.dialect.PostgreSQLDialect</property>
<property name="cache.provider_class">org.hibernate.cache.HashtableCacheProvider</property>
<property name="transaction.factory_class">org.hibernate.transaction.JDBCTransactionFactory</property>

<!-- thread is the short name for org.hibernate.context.ThreadLocalSessionContext -->
<property name="current_session_context_class">thread</property>

<!-- Set "true" to show SQL statements -->
<property name="hibernate.show_sql">true</property>

<!-- mapping class using annotation -->
<mapping class="com.hib.entities.Student"></mapping>
</session-factory>

</hibernate-configuration>

src/main/java/

package com.hib.init;

import org.hibernate.SessionFactory;
import org.hibernate.cfg.Configuration;
import org.hibernate.service.ServiceRegistry;
import org.hibernate.service.ServiceRegistryBuilder;

public class Hibernateutil {
private static final SessionFactory sessionF;
private static final ServiceRegistry serviceR;

static {
    Configuration conf = new Configuration();
    conf.configure();
    System.out.println("Begin");
    serviceR = new ServiceRegistryBuilder().applySettings(conf.getProperties()).buildServiceRegistry();
    System.out.println("Ready???");
    try {
        sessionF = conf.buildSessionFactory(serviceR);
        System.out.println("Success??");
    }catch(Exception e) {
        throw new ExceptionInInitializerError(e);
    }
}

public static SessionFactory getSeeionFactory() {
    return sessionF;
}
}

src/main/java package com.hib.entities;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.Table;

@Entity
@Table
public class Student {

@Id
@GeneratedValue
private Integer id;
private String firstName;

private Integer age;

public Student() {}

public Student(Integer id, String firstName, Integer age) {
    super();
    this.id = id;
    this.firstName = firstName;
    this.age = age;
}

public Integer getId() {
    return id;
}

public void setId(Integer id) {
    this.id = id;
}

public String getFirstName() {
    return firstName;
}

public void setFirstName(String firstName) {
    this.firstName = firstName;
}

public Integer getAge() {
    return age;
}

public void setAge(Integer age) {
    this.age = age;
}   
}

src/main/java

package com.hib.demo;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import com.hib.entities.Student;
import com.hib.init.Hibernateutil;

public class DemoFirst {

public static void main(String[] args) {
    SessionFactory sessionFactory = Hibernateutil.getSeeionFactory();
    Session session = sessionFactory.openSession();
    session.beginTransaction();

    Student student = new Student();
    student.setFirstName("Bob");
    student.setAge(26);

    session.save(student);
    session.getTransaction().commit();

    session.close();
}
}

And this is the error I got :

Success??
Hibernate: select nextval ('hibernate_sequence')
Aug 12, 2014 11:01:10 PM org.hibernate.engine.jdbc.spi.SqlExceptionHelper logExceptions
WARN: SQL Error: 0, SQLState: 42P01
Aug 12, 2014 11:01:10 PM org.hibernate.engine.jdbc.spi.SqlExceptionHelper logExceptions
ERROR: ERROR: relation "hibernate_sequence" does not exist
Position: 17
Exception in thread "main" org.hibernate.exception.SQLGrammarException: ERROR: relation        "hibernate_sequence" does not exist
Position: 17
at org.hibernate.exception.internal.SQLStateConversionDelegate.convert(SQLStateConversionDelegate.java:122)
at org.hibernate.exception.internal.StandardSQLExceptionConverter.convert(StandardSQLExceptionConverter.java:47)
at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:125)
at org.hibernate.engine.jdbc.spi.SqlExceptionHelper.convert(SqlExceptionHelper.java:110)
at org.hibernate.engine.jdbc.internal.proxy.AbstractStatementProxyHandler.continueInvocation(AbstractStatementProxyHandler.java:129)
at org.hibernate.engine.jdbc.internal.proxy.AbstractProxyHandler.invoke(AbstractProxyHandler.java:81)
at com.sun.proxy.$Proxy9.executeQuery(Unknown Source)
at org.hibernate.id.SequenceGenerator.generateHolder(SequenceGenerator.java:123)
at org.hibernate.id.SequenceGenerator.generate(SequenceGenerator.java:116)
at org.hibernate.event.internal.AbstractSaveEventListener.saveWithGeneratedId(AbstractSaveEventListener.java:120)
at org.hibernate.event.internal.DefaultSaveOrUpdateEventListener.saveWithGeneratedOrRequestedId(DefaultSaveOrUpdateEventListener.java:204)
at org.hibernate.event.internal.DefaultSaveEventListener.saveWithGeneratedOrRequestedId(DefaultSaveEventListener.java:55)
at org.hibernate.event.internal.DefaultSaveOrUpdateEventListener.entityIsTransient(DefaultSaveOrUpdateEventListener.java:189)
at org.hibernate.event.internal.DefaultSaveEventListener.performSaveOrUpdate(DefaultSaveEventListener.java:49)
at org.hibernate.event.internal.DefaultSaveOrUpdateEventListener.onSaveOrUpdate(DefaultSaveOrUpdateEventListener.java:90)
at org.hibernate.internal.SessionImpl.fireSave(SessionImpl.java:642)
at org.hibernate.internal.SessionImpl.save(SessionImpl.java:635)
at org.hibernate.internal.SessionImpl.save(SessionImpl.java:631)
at com.hib.demo.DemoFirst.main(DemoFirst.java:20)


Caused by: org.postgresql.util.PSQLException: ERROR: relation "hibernate_sequence" does not exist
Position: 17
at    org.postgresql.core.v3.QueryExecutorImpl.receiveErrorResponse(QueryExecutorImpl.java:2062)
at org.postgresql.core.v3.QueryExecutorImpl.processResults(QueryExecutorImpl.java:1795)
at org.postgresql.core.v3.QueryExecutorImpl.execute(QueryExecutorImpl.java:257)
at org.postgresql.jdbc2.AbstractJdbc2Statement.execute(AbstractJdbc2Statement.java:479)
at org.postgresql.jdbc2.AbstractJdbc2Statement.executeWithFlags(AbstractJdbc2Statement.java:367)
at org.postgresql.jdbc2.AbstractJdbc2Statement.executeQuery(AbstractJdbc2Statement.java:271)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.hibernate.engine.jdbc.internal.proxy.AbstractStatementProxyHandler.continueInvocation(AbstractStatementProxyHandler.java:122)
... 14 more

pom.xml

 <dependency>
    <groupId>postgresql</groupId>
    <artifactId>postgresql</artifactId>
    <version>8.4-701.jdbc4</version>
</dependency>

Michael Zhavzharov · Accepted Answer · 2014-08-13 06:39:51Z

up vote 1 down vote accepted

According to this thread you must set your Id annotation as follows:

@GeneratedValue(strategy = GenerationType.IDENTITY)

answered Aug 13 '14 at 6:39

Michael Zhavzharov
1,114415

Thank you. It works – user3819470 Aug 13 '14 at 6:49

add a comment |

Cortwave · Answer 2 · 2014-08-13 06:37:34Z

You should make mapping beetwen table-entity class, column- field. For example (table and columns should exist) :

@Entity
@Table(name = "student")
public class Student {

@Id
@GeneratedValue
@Column(name = "id")
private Integer id;

@Column(name = "first_name")
private String firstName;

@Column(name = "age")
private Integer age;

Vlad Mihalcea · Answer 3 · 2014-08-13 06:46:31Z

You forgot to add the DDL auto generation property. You can use any of the following settings:

<property name="hibernate.hbm2ddl.auto" value="update">
<property name="hibernate.hbm2ddl.auto" value="create">
<property name="hibernate.hbm2ddl.auto" value="create-drop">

update is going to create and then simply update the DDL schema
create is going to create the schema if it doesn't exist
create-drop will create the schema when the SessionFactory is initialized and destroy it when the SessionFactory is destroyed. This is useful during integration testing.

Mayur Gupta · Answer 4 · 2014-08-13 06:49:40Z

Because you are using @GeneratedValue()

It will look for how the database that you are using generates ids. For MySql or HSQSL, there are increment fields that automatically increment. In Postgres or Oracle, they use sequence tables. Since you didn't specify a sequence table name, it will look for a sequence table named hibernate_sequence and use it for default. So you probably don't have such a sequence table in your database and now you get that error.

Either add a hibernate_sequence like

@GeneratedValue(strategy=SEQUENCE)

or your own sequence table and use the annotations to name your sequence table that you have like

@GeneratedValue(strategy=SEQUENCE, generator="student_id_seq")

Hope that helps

asked	8 months ago
viewed	552 times
active	8 months ago

current community

your communities

more stack exchange communities

How to connect postgresql in hibernate.cfg.xml

4 Answers 4

Your Answer

Not the answer you're looking for? Browse other questions tagged java spring hibernate postgresql or ask your own question.

Visit Chat

Linked

Hot Network Questions

current community

your communities

more stack exchange communities

How to connect postgresql in hibernate.cfg.xml

4 Answers 4

Your Answer

Sign up or log in

Post as a guest

Not the answer you're looking for? Browse other questions tagged java spring hibernate postgresql or ask your own question.

Visit Chat

Linked

Related

Hot Network Questions