JAVA全系列 教程
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在商品服务模块编写商品规格和商品规格项Mapper
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public interface SpecificationMapper extends BaseMapper<Specification> {
Specification findById(Long id);
// 根据商品类型查询商品规格
List<Specification> findByProductTypeId(Long productTypeId);
}
public interface SpecificationOptionMapper extends BaseMapper<SpecificationOption> {
}
在resources
中创建SpecificationMapper
的同级包,编写映射文件SpecificationMapper.xml
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<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.itbaizhan.shopping_goods_service.mapper.SpecificationMapper">
<resultMap id="specificationMapper" type="com.itbaizhan.shopping_common.pojo.Specification">
<id property="id" column="bid"></id>
<result property="specName" column="specName"></result>
<result property="productTypeId" column="productTypeId"></result>
<collection property="specificationOptions" column="specId" ofType="com.itbaizhan.shopping_common.pojo.SpecificationOption">
<id property="id" column="oid"></id>
<result property="optionName" column="optionName"></result>
<result property="specId" column="specId"></result>
</collection>
</resultMap>
<select id="findById" parameterType="long" resultMap="specificationMapper">
SELECT
bz_specification.id AS bid,
bz_specification.specName,
bz_specification.productTypeId,
bz_specification_option.id AS oid,
bz_specification_option.optionName,
bz_specification_option.specId
FROM bz_specification
LEFT JOIN bz_specification_option
on bz_specification.id = bz_specification_option.specId
where bz_specification.id = #{id}
</select>
<select id="findByProductTypeId" parameterType="long" resultMap="specificationMapper">
SELECT
bz_specification.id AS bid,
bz_specification.specName,
bz_specification.productTypeId,
bz_specification_option.id AS oid,
bz_specification_option.optionName,
bz_specification_option.specId
FROM bz_specification
LEFT JOIN bz_specification_option
on bz_specification.id = bz_specification_option.specId
where bz_specification.productTypeId = #{productTypeId}
</select>
</mapper>