hql基本查詢語句

 

package com.etp.bbs.dao;

import java.util.List;

import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.Transaction;

import com.etp.bbs.pojo.User;

public class UserDao_H
{

 

 public List<User> getAllUser_01()
 {
  List<User> userList = null;
  String hql = "from User";
  Session session = null;
  Transaction tran = null;
  try
  {
   session = HibernateUtil.getSession();
   Query query = session.createQuery(hql);
   userList = query.list();
  }
  catch (Exception e)
  {
   // TODO: handle exception
  }
  return userList;
 }

 

 

 

 public List<User> getAllUserByPage(int pageNum)
 {
  int start = (pageNum - 1) * 2;
  List<User> userList = null;
  String hql = "from User";
  Session session = null;
  Transaction tran = null;
  try
  {
   session = HibernateUtil.getSession();
   Query query = session.createQuery(hql);
   query.setFirstResult(start);
   query.setMaxResults(2);
   userList = query.list();
  }
  catch (Exception e)
  {
   e.printStackTrace();
  }
  return userList;
 }

 

 

 public List getAllUser_02()
 {
  List userList = null;
  String hql = "select u.userName,u.regTime from User u";
  Session session = null;
  try
  {
   session = HibernateUtil.getSession();
   Query query = session.createQuery(hql);
   userList = query.list();
  }
  catch (Exception e)
  {
   // TODO: handle exception
  }
  return userList;
 }

 

 

 public User getUserById_01(int id)
 {
  User user = null;
  String hql = "from User u where u.userId = ?";
  Session session = null;
  Transaction tran = null;
  try
  {
   session = HibernateUtil.getSession();
   Query query = session.createQuery(hql);
   query.setInteger(0, id);
   user = (User) query.list().get(0);
  }
  catch (Exception e)
  {
   // TODO: handle exception
  }
  return user;
 }

 

 

 public User getUserById_02(int id)
 {
  User user = null;
  String hql = "from User u where u.userId = ?";
  Session session = null;
  Transaction tran = null;
  try
  {
   session = HibernateUtil.getSession();
   Query query = session.createQuery(hql);
   query.setInteger(0, id);
   user = (User) query.uniqueResult();
  }
  catch (Exception e)
  {
   
  }
  return user;
 }

 

 

 public User getUserById_03(int id)
 {
  User user = null;
  String hql = "from User u where u.userId = :id";
  Session session = null;
  Transaction tran = null;
  try
  {
   session = HibernateUtil.getSession();
   Query query = session.createQuery(hql);
   query.setInteger("id", id);
   user = (User) query.uniqueResult();
  }
  catch (Exception e)
  {
  }
  return user;
 }

 

 

 // 模糊查詢
 public List<User> getUserByUserName(String userName)
 {
  List<User> userList = null;
  String hql = "from User u where u.uName like :userName";
  Session session = null;
  Transaction tran = null;
  try
  {
   session = HibernateUtil.getSession();
   Query query = session.createQuery(hql);
   query.setString("userName", "%" + userName + "%");
   userList = query.list();
  }
  catch (Exception e)
  {

  }
  return userList;
 }

 

 

 // 取出欄位
 public List<String> getAllUserName()
 {
  List<String> nameList = null;
  String hql = "select u.userName from User u";
  Session session = null;
  try
  {
   session = HibernateUtil.getSession();
   Query query = session.createQuery(hql);
   nameList = query.list();
  }
  catch (Exception e)
  {
   // TODO: handle exception
  }
  return nameList;
 }

 

 

 // 計數
 public long getUserCount()
 {
  long result = -1;
  String hql = "select count(*) from User";
  Session session = null;
  try
  {
   session = HibernateUtil.getSession();
   Query query = session.createQuery(hql);
   result = (Long) query.uniqueResult();
  }
  catch (Exception e)
  {

  }
  return result;
 }

 

 

 // 關聯
 public User getUserTopicByUserId(int userId)
 {
  User user = null;
  String hql = "select u from User u join fetch u.topics where u.userId = ?";
  Session session = null;
  try
  {
   session = HibernateUtil.getSession();
   Query query = session.createQuery(hql);
   query.setInteger(0, userId);
   user = (User) query.uniqueResult();
  }
  catch (Exception e)
  {
   
  }
  return user;
 }
}