hibernate 多表查询

 1     public List dzcx(Object a) {
 2         try{
 3             
 4             //Query p=getSession().createQuery("PersonInf where name=:name ");
 5             Query p=getSession().createQuery("select p.name,p.age,a.addressDetail from PersonInf as p" +
 6                     " inner join p.addressInfs as a" +
 7                     " where a.addressDetail=:a" );
 8             //要加上select就要加上别名
 9             //多个表之间查询加上   inner join
10             p.setParameter("a", a);
11             return    p.list();
12         }
13         catch(RuntimeException e)
14         {
15             log.error("find Name failed", e);
16             throw e;
17         }

select p.name,p.age,a.addressDetail from PersonInf as p inner join p.addressInfs as a where a.addressDetail=:a 

这里是根据地址查询，显示名字、年龄、地址。 inner join  自动链接中间表，根据p.addressInfs 找到addressInf表。

 

 

调用查询：

<%

 PersonInfDAO p=new PersonInfDAO();

List a=p.dzcx("垫江");

Iterator it=a.iterator();

while(it.hasNext()){

 Object[] pit=(Object[])it.next();//注意若是返回的是一个值，而不是一个数组，那么这里就应该是Object pit=(Object)it.next();

out.print(pit[0]);

out.print(pit[1]);

out.print(pit[2]);

}

%>