Hibernate面试题部分汇总集合(17)
时间:2025-02-28
时间:2025-02-28
此文档主要简绍J2EE中的hibernate面试突击问题部分集合
while(it.hasNext()){
Address address=(Address)it.next();
System.out.println(address.getAddress());
}
System.out.println(“Second query……”);
User user2=(User)session.load(User.class,”1”);
Collection it2=user2.getAddresses();
while(it2.hasNext()){
Address address2=(Address)it2.next();
System.out.println(address2.getAddress());
}
运行这段代码,会得到类似下面的输出:
Select * from user where id=’1’;
Select * from address where user_id=’1’;
Tianjin
Dalian
Second query……
Select * from address where id=’1’;
Select * from address where id=’2’;
Tianjin
Dalian
我们看到,当第二次执行查询时,执行了两条对address表的查询操作,为什么