Hibernate Select Clause


In this lesson we will write example code to select the data from Insurance table using Hibernate Select Clause. The select clause picks up objects and properties to return in the query result set. Here is the query:
Select insurance.lngInsuranceId, insurance.insuranceName, insurance.investementAmount, insurance.investementDate from Insurance insurance
which selects all the rows (insurance.lngInsuranceId, insurance.insuranceName, insurance.investementAmount, insurance.investementDate) from Insurance table.
Hibernate generates the necessary sql query and selects all the records from Insurance table. Here is the code of our java file which shows how select HQL can be used:

package roseindia.tutorial.hibernate;

import org.hibernate.Session;
import org.hibernate.*;
import org.hibernate.cfg.*;

import java.util.*;

/**
 * @author Deepak Kumar
 *
 * http://www.roseindia.net
 * HQL Select Clause Example
 */
public class SelectClauseExample {
  public static void main(String[] args) {
  Session session = null;

  try{
  // This step will read hibernate.cfg.xml 
and prepare hibernate for use
  SessionFactory sessionFactory = new 
Configuration().configure()
.buildSessionFactory();
  session =sessionFactory.openSession();
 
  //Create Select Clause HQL
 String SQL_QUERY ="Select insurance.
lngInsuranceId,insurance.insuranceName," + 
 "insurance.investementAmount,insurance.
investementDate from Insurance insurance";
 Query query = session.createQuery(SQL_QUERY);
 for(Iterator it=query.iterate();it.hasNext();){
 Object[] row = (Object[]) it.next();
 System.out.println("ID: " + row[0]);
 System.out.println("Name: " + row[1]);
 System.out.println("Amount: " + row[2]);
 }
 
  session.close();
  }catch(Exception e){
  System.out.println(e.getMessage());
  }finally{
  }
  }
}
To run the example select Run-> Run As -> Java Application from the menu bar. Following out is displayed in the Eclipse console:
Hibernate: select insurance0_.ID as col_0_0_, insurance0_.insurance_name as col_1_0_, insurance0_.invested_amount as col_2_0_, insurance0_.investement_date as col_3_0_ from insurance insurance0_
ID: 1
Name: Car Insurance
Amount: 1000
ID: 2
Name: Life Insurance
Amount: 100
ID: 3
Name: Life Insurance
Amount: 500
ID: 4
Name: Car Insurance
Amount: 2500
ID: 5
Name: Dental Insurance
Amount: 500
ID: 6
Name: Life Insurance
Amount: 900
ID: 7
Name: Travel Insurance
Amount: 2000
ID: 8
Name: Travel Insurance
Amount: 600
ID: 9
Name: Medical Insurance
Amount: 700
ID: 10
Name: Medical Insurance
Amount: 900
ID: 11
Name: Home Insurance
Amount: 800
ID: 12
Name: Home Insurance
Amount: 750
ID: 13
Name: Motorcycle Insurance
Amount: 900
ID: 14
Name: Motorcycle Insurance
Amount: 780

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