hibernate select语句返回的类型

Person类中包含有MyEvent这个类 java

public class Person{
   private Long id;
   private String name;
   private MyEvent myEvent;
}

1、HQL from语句 

一、结果类型:List<Person>

from Person  或者 from Person as p
from Person as p where p.myEvent.title = :title
注意:hibernate3.2.3以前老是对的。 
   hibernate3.2.3以后若是myEvent是普通属性或关联的实体也是对的,若是myEvent是一个集合会出异常 
   所以hibernate推荐使用下面的方式:
select p from Person as p inner join p.myEvent as e where e.title = :title

二、结果类型 List<Person,Event>

from Person as p inner join p.myEvent as event where event.title = : title
注:查询出来是:是一个集合,集合元素是Person,myEvent组成的数组。 
   结果类型: List<Person,Event> 
from Person as p left outer join p.myEvent as event where event.title = : title

注意:查询出来是:是一个集合,集合元素是Person,myEvent组成的数组。 
           结果类型: List<Person,Event>
数组

from Person as p right outer join p.myEvent as event where event.title = : title
from Person as p full join p.myEvent as event where event.title = : title

第二:HQL select语句 

一、结果类型:  List<String> 

select p.name from Person as p

二、结果类型:List<Object[String,Person]>

select p.name,p from Person as p

三、结果类型:List<String,String>

select new List(p.name,p.address) from Person as p

四、结果类型:List<ClassTest>

select new ClassTest(p.name,p.address) from Person as p

   注意:前提ClassTest 类有两个参数的构造器。 spa

五、结果类型:List<map<String,String>>

select new map(p.name as personName) from Person as p
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