HQL Order By Example

Order by clause is used to retrieve the data from database in the sorted order by any property of returned class or components. HQL supports Order By Clause. In our example we will retrieve the data sorted on the userName type. Here is the java example code:

"FROM UserDetails user ORDER BY user.userName DESC" 

UserDetails.java
package com.sdnext.hibernate.tutorial.dto;

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

@Entity
@Table(name="USERS")
public class UserDetails 
{
 @Id
 @Column(name="USER_ID")
 @GeneratedValue(strategy=GenerationType.AUTO)
 private int userId;
 
 @Column(name="USER_NAME")
 private String userName;
 
 public int getUserId() {
  return userId;
 }
 public void setUserId(int userId) {
  this.userId = userId;
 }
 public String getUserName() {
  return userName;
 }
 public void setUserName(String userName) {
  this.userName = userName;
 }
}
hibernate.cfg.xml
<!!DOCTYPE hibernate-configuration PUBLIC
        "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
        "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">

<hibernate-configuration> 
 <session-factory> 
  <!-- Database connection settings -->
   <property name="connection.driver_class">com.mysql.jdbc.Driver</property> 
   <property name="connection.url">jdbc:mysql://localhost:3306/hibernateDB</property> 
   <property name="connection.username">root</property> 
   <property name="connection.password">root</property> 

  <!-- JDBC connection pool (use the built-in) -->
   <property name="connection.pool_size">1</property> 

  <!-- SQL dialect -->
   <property name="dialect">org.hibernate.dialect.MySQLDialect</property> 

  <!-- Enable Hibernate's automatic session context management -->
    <property name="current_session_context_class">thread</property> 
  
  <!-- Disable the second-level cache -->
   <property name="cache.provider_class">org.hibernate.cache.NoCacheProvider</property> 

  <!-- Echo all executed SQL to stdout -->
   <property name="show_sql">true</property> 
  
  <!-- Drop and re-create the database schema on startup -->
   <property name="hbm2ddl.auto">update</property> 
    
   <mapping class="com.sdnext.hibernate.tutorial.dto.UserDetails">
  
  </mapping></session-factory> 
 </hibernate-configuration>
HibernateTestDemo.java
package com.sdnext.hibernate.tutorial;

import java.util.Iterator;

import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.cfg.AnnotationConfiguration;

import com.sdnext.hibernate.tutorial.dto.UserDetails;

public class HibernateTestDemo {

 /**
  * @param args
  */
 public static void main(String[] args) 
 {
  SessionFactory sessionFactory = new AnnotationConfiguration().configure().buildSessionFactory();
  Session session = sessionFactory.openSession();
  session.beginTransaction();
  
  String SQL_QUERY = "FROM UserDetails user ORDER BY user.userName DESC";
  Query query = session.createQuery(SQL_QUERY);
    
  for(Iterator it=query.iterate();it.hasNext();)
  {
   UserDetails user = (UserDetails)it.next();
   System.out.println("User Name: " + user.getUserName());
   System.out.println("User Id: " + user.getUserId());
  }
  session.getTransaction().commit();
  session.close();
 }
}
Output:
log4j:WARN No appenders could be found for logger (org.hibernate.cfg.annotations.Version).
log4j:WARN Please initialize the log4j system properly.
Hibernate: select userdetail0_.USER_ID as col_0_0_ from USERS userdetail0_ order by userdetail0_.USER_NAME DESC
Hibernate: select userdetail0_.USER_ID as USER1_0_0_, userdetail0_.USER_NAME as USER2_0_0_ from USERS userdetail0_ where userdetail0_.USER_ID=?
User Name: Sweety Rajput
User Id: 2
Hibernate: select userdetail0_.USER_ID as USER1_0_0_, userdetail0_.USER_NAME as USER2_0_0_ from USERS userdetail0_ where userdetail0_.USER_ID=?
User Name: Dinesh Rajput
User Id: 1
Hibernate: select userdetail0_.USER_ID as USER1_0_0_, userdetail0_.USER_NAME as USER2_0_0_ from USERS userdetail0_ where userdetail0_.USER_ID=?
User Name: Dev Rajput
User Id: 3
Hibernate: select userdetail0_.USER_ID as USER1_0_0_, userdetail0_.USER_NAME as USER2_0_0_ from USERS userdetail0_ where userdetail0_.USER_ID=?
User Name: Anamika Rajput
User Id: 4




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