hibernate中使用sql

hibernate的使用
1，hibernate中执行sql语句，返回一个在映射文件中已经映射的对象：

public List<Menu> findMenusByEntityTypeId(Long id) {
        String hql = "select m.id as {menu.id},m.name as {menu.name},m.url as {menu.url},m.icon_url as {menu.iconUrl},m.parent_id as {menu.parentId},"
                                +"m.serial_number as {menu.serialNo},m.admin as {menu.adminUse},m.system_admin as {menu.systemAdmin} ,m.program_name as {menu.programName}"
                                +" from menu m, entity_type et, entity_admin_menu eam"
                                +" where et.id = "+id+""
                                +" and m.program_name = '"+GlobalNames.PROGRAM_NAME_CHSS+"'"
                                +" and et.id = eam.entity_id"
                                +" and m.id = eam.menu_id";
        List<Menu> menus = super.getSessionFactory().getCurrentSession().createSQLQuery(hql).addEntity("menu",Menu.class).list();
        return menus;
}

2，hibernate中使用sql语句，返回一个count的统计值：

String sql = "select count(distinct(order_id)) from t_credit_log where usercode = :usercode ";
		Query query = ht.getSessionFactory().openSession().createSQLQuery(sql)
				.setParameter("usercode", usercode);//传值也可以用位置 
		List list = query.list();
		BigDecimal count = list == null || list.size() <= 0 ? new BigDecimal(0)
				: (BigDecimal) list.get(0);
		if (count.intValue() >= 3) {
			flag = true;
		}

3，hibernate使用sql查询，返回一个没有映射的对象：
如果要执行的sql语句是多表查询，并且是返回一个对象。但是这个对象是没有配置hibernate映射的。这种就麻烦了。hibernate执行SQL默认返回的是一个object类型的数组，

List menus =super.getSessionFactory().getCurrentSession().createSQLQuery(hql).list();
for(int i=0;i<menus .size();i++)
{Object[] objects = (Object[])menus .get(i);for(int j=0;j<objects.length;j++)
{System.out.println(objects[j].getClass().getName());}

运行后报错：java.lang.ClassCastExceptionjava.lang.Object; cannot be cast to net.greatsoft.chss.domain.privilege.model.Menu，原来是查询出来的字段并不能自动转换为bean对象，所以要添加addEntity(Clazz class)。有人肯定会说添加addEntity了，但是如果Menu没有添加hibernate映射的话，此时会报Menu unmapping。。。。。。就是没添加映射，
所以只能添加setResultTransformer(Transformers.ALIAS_TO_ENTITY_MAP); //返回一个map,KEY:为DB中名称一致（大小写一致）遍历list时就可以。所以只能将返回的值变成Map，这样就好操作了，然后就可用反射取值了，详细看：hibernate 执行sql语句返回自定义对象

4，hibernate使用sql，修改,删除DB

    SQLQuery query = this.getSession().createSQLQuery(sql);    
    result = query.executeUpdate();  

5，hibernate使用sql，往DB插入数据

public int insertValue(int pid,String vcode,String vvalue,String state,String mname){
		Session session = null;
		Transaction tr = null;
		Connection con = null; 
		PreparedStatement ps = null; 
		try{
			if(pid>0&&vcode!=null&&vvalue!=null&&mname!=null){
				session = getSession();
				String sql = "insert into sf_3_clinic(pid,"+vcode+") values("+pid+","+vvalue+")"; 
				session = getHibernateTemplate().getSessionFactory().openSession(); 
				tr = session.beginTransaction(); 
				con = session.connection(); 
				ps = con.prepareStatement(sql); 
				ps.executeUpdate(); 
				tr.commit(); 
				
				return 1;
			}return 0;
		}catch(Exception e){
			e.printStackTrace();
			return 0;
		}finally{
			try{
				//判断不等于null，之后再关闭
				session.close();
				con.close();
				ps.close();
			}catch(Exception e){
			}
		}
	}