BE THE CODER > Hibernate > Hibernate Query Language (HQL) > Create Map using Aggregate Functions

The following example shows creating map from the results of aggregate functions. Refer first example for the configuration and mapping.

File Name :	com/bethecoder/tutorials/hibernate/basic/tests/HQLMinMaxCountMapTest.java
Author :	Sudhakar KV
Email :	[email protected]


package com.bethecoder.tutorials.hibernate.basic.tests;



import java.util.Map;

import org.hibernate.Session;

import com.bethecoder.tutorials.hibernate.basic.util.HibernateUtil;



public class HQLMinMaxCountMapTest {



  /**

   * @param args

   */

  public static void main(String[] args) {



    Session session = HibernateUtil.getSessionFactory().openSession();

    session.beginTransaction();

    

    String HQL_QUERY = "select new map(max(projectCount) as max_project_count," + 

      "min(employeeCount) as min_emp_count, count(*) as company_count) from Company comp";

    

    /**

     * If the above query does'nt return unique result, the

     * 'uniqueResult' method throws an exception.

     * 

     *  org.hibernate.NonUniqueResultException: query did not return a unique result: 8

     *  

     *  So be sure while using this method.

     */

    Map stats = (Map) session.createQuery(HQL_QUERY).uniqueResult();    

    System.out.println(stats);



    session.getTransaction().commit();

    session.close();

  }



}