1.多表查询问题大的很，除了用nativeSQL以外，还有三个解决办法：
MEthod 1:
private void testUseJDBCInHibernate() throws SQLException{
Connection conn =super.getSession().connection(); //JDBC Connection
String sql="update BBS_TOPIC set RESPONSE_NUM=RESPONSE_NUM+1 where ID=?";
PreparedStatement ps =conn.prepareStatement(sql);
ps.setInt(1, 1001);
ps.execute();
}
说明，当session里有了一个BO，假如你这个时候再去update或者insert，那么他会报错说，一个session里拥有多个不同的ReferenceID。这个时候你就得用JDBC的update语句来解决。
Method2：
private List getTotalCharge(Date statTimeBegin,Date statTimeEnd){
List res = new Vector();//将用于存放保存的结果集合
Session session = null;
ScrollableResults srs = null;
session =super.getSession();
srs = session.createQuery("select b.name, count(a.fee) mix(a.chargeBeginTime) max(a.chargeEndTime) from charge a, customer b where a.idCustomer = b.idCustomer and a.chargeBeginTime >= ? and a.chargeEndTime < ? gourp by a.idCustomer").setDate(0, statTimeBegin).setDate(1, statTimeEnd).scroll();
//将查询结果放入List保存
while(srs.next()){
res.add(new TotalCharge(srs.getString(0), srs.getDouble(1), srs.getDate(2),srs.getDate(3)));
}
return res;
}
Method3：
在Hibernate中使用Apache的Commons_DB_util
public List query(String sql,Class clazz){//clazz 为BO with setter and getter
Connection conn = super.getSession().connection(); //JDBC Connection
QueryRunner qRunner = new QueryRunner();
List beans = (List) qRunner.query(conn,sqlString,new BeanListHandler(clazz));
return beans;
}