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  • Hibernate:1对1关系总结。

    QQ和QQ空间是1对1关系:配置如下

    一、主键关联,双方共同维护表关系,以主键关联

    public class QQ {
    
    	private Long id;
    	 private QQZone zone;
    }
    public class QQZone {
    
    	private Long id;
    	private QQ qq;
    }
    <hibernate-mapping package="com.bohe.domain">
    
    	<class name="QQ" table="qq">
    		<id name="id" column="ID">
    			<generator class="native" />
    		</id>
    		<one-to-one name="zone" />
    		 
    	</class>
    
    </hibernate-mapping>
    <hibernate-mapping package="com.bohe.domain">
    
    	<class name="QQZone" table="qqzone">
    		<id name="id" column="ID">
    			<generator class="native" />
    		</id>
    		<one-to-one name="qq" />
    		
    	</class>
    
    </hibernate-mapping>


    二、用many-to-one模仿one-to-one,qq表为主表,qqzone为从表

    public class QQ {
    
    	private Long id;
    	 private QQZone zone;
    }


     

    public class QQZone {
    
    	private Long id;
    	private QQ qq;
    }
    <hibernate-mapping package="com.bohe.domain">
    
    	<class name="QQ" table="qq">
    		<id name="id" column="ID">
    			<generator class="native" />
    		</id>
    		<one-to-one name="zone" />
    		 
    	</class>
    
    </hibernate-mapping>
    <hibernate-mapping package="com.bohe.domain">
    
    	<class name="QQZone" table="qqzone">
    		<id name="id" column="ID">
    			<generator class="native" />
    		</id>
    		
    		<many-to-one name="qq" column="qq_id" unique="true"/> 
    	</class>
    
    </hibernate-mapping>


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  • 原文地址:https://www.cnblogs.com/james1207/p/3268648.html
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