HIBERNATE 双向一对一查询对象老是 N+1

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HIBERNATE 双向一对一查询对象老是 N+15

环境很简单,两个类，Book 和 BookDetail,唯一外键类型的双向一对一，互相引用

public class Book {
	private int id;
	private String name;
	
	private BookDetail detail;
}

public class BookDetail {
	private int id;
	private String summary;

	private Book book;
}

两个类的hbm文件：

<hibernate-mapping package="com.sina.domain">
	<class name="Book" table="Book" dynamic-insert="true" dynamic-update="true">
		<id name="id" type="int">
			<generator class="identity"></generator>
		</id>
		
		<property name="name" type="string" not-null="true"/>
		<!-- 
		 -->
		<one-to-one name="detail" class="BookDetail" property-ref="book"/>
	</class>
</hibernate-mapping>

 <hibernate-mapping package="com.sina.domain">
	<class name="BookDetail" table="BookDetail" dynamic-insert="true" dynamic-update="true" batch-size="10">
		<id name="id" type="int">
			<generator class="identity"></generator>
		</id>
		<property name="summary" type="string" />
		
		<many-to-one name="book" column="book_id" class="Book" unique="true"/>
	</class>
</hibernate-mapping>

加入数据库里有3条Book记录，3条BookDetail记录
如果我只想查book，不想查BookDetail针对book查询：

// There are for example 3 books in DB
List<Book> booklist = session.createQuery("from Book b").list();

却得到一下的SQL:

Hibernate: select book0_.id as id1_0_, book0_.name as name2_0_ from Book book0_
Hibernate: select bookdetail0_.id as id1_1_0_, bookdetail0_.summary as summary2_1_0_, bookdetail0_.book_id as book_id3_1_0_ from BookDetail bookdetail0_ where bookdetail0_.book_id=?
Hibernate: select bookdetail0_.id as id1_1_0_, bookdetail0_.summary as summary2_1_0_, bookdetail0_.book_id as book_id3_1_0_ from BookDetail bookdetail0_ where bookdetail0_.book_id=?
Hibernate: select bookdetail0_.id as id1_1_0_, bookdetail0_.summary as summary2_1_0_, bookdetail0_.book_id as book_id3_1_0_ from BookDetail bookdetail0_ where bookdetail0_.book_id=?

无缘无辜多了3条BookDetail的sql，请问怎么设置能够只查Book（Book对象里的的关联detail采用懒加载），谢谢

问题补充：hen
谢谢楼上的两位，查了好久，终于知道答案了，因为这种以唯一外键的一对一，由于外键在BookDetail中，如果访问Book，由于Book没有外键，所以当填充Book中的detail属性的时候，由于拿不到外键（如果有外键的话，空就为null，有外键就proxy一个主键为此外键的代理对象），所以只能查BookDetail表，如果为空，则设置detail对象为空，如果有一条记录，则设置detail为此记录，如果多于1条，则报错（非唯一），基本的流程是这样，解决的方法是由于BookDetail容量比较大，Book较小，所以将外键放到Book里面比较好，这样查Book的时候不会加载BookDetail。写了这么多希望后来碰到这个双向一对一的人看到