Ibatis一对多的延迟加载应用
我们的应用之中有一个一对多的情况 :
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一个批发产品对应3条批发价格信息
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于是model 结构 ；?
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public class ProductVo implements Serializable { private List<WholesaleRange> wholeRageList; //价格信息集合 public List<WholesaleRange> getWholeRageList() { return wholeRageList; } public void setWholeRageList(List<WholesaleRange> wholeRageList) { this.wholeRageList = wholeRageList; }}?
如何查询批发信息的时候直接带出附加的价格信息集合呢 ？
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SQLMAP 如下构建：
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<typeAlias alias="wholesaleprd" type="com.woyo.business.wholesale.domain.model.ProductVo" /> <resultMap id="wholesalePriceRageMap" > <result column="id" property="id" jdbcType="VARCHAR" /> <result column="title" property="title" jdbcType="VARCHAR" /> <result column="is_mixed_batch" property="mixedBatch" nullValue="0" /> <result column="id" property="wholeRageList" select="getWholeRageList"/> </resultMap><select id="getWholeRageList" resultparameterresultMap="wholesalePriceRageMap" parameterClass="long"> SELECT w.id as id ,w.title as title, p.id as prdId,p.product_name AS prdName ,p.count - w.order_amount AS balance_amount , p.price AS price, p.image_url AS imageUrl, w.supplier_name, w.supplier_tel, w.wholesale_amount, w.wholesale_price, w.team_price, w.team_save, w.order_amount, w.team_amount ,w.is_mixed_batch FROM wholesale w left join product p on w.product_id = p.id where w.id = #value# </select>
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这样， 查询出的对象， Ibatis 会用延迟加载的策略来得到 wholeRageList?
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