order_items表中有product_id products表中有id我怎么使用mybatis实现两个表联合查询给出我需要新建的文件名以及代码我的工程是comecommercebook。实体类目录是pojo我的orderitemmapperxml是xml version=10 encoding=UTF-8!DOCTYPE mapper PUBLIC -mybatisorgDTD

<resultMap id="BaseResultMap" type="com.ecommerce.book.pojo.Product">
    <id property="id" column="id" jdbcType="INTEGER"/>
    <result property="name" column="name" jdbcType="VARCHAR"/>
    <result property="description" column="description" jdbcType="VARCHAR"/>
    <result property="price" column="price" jdbcType="DECIMAL"/>
    <result property="createdAt" column="created_at" jdbcType="TIMESTAMP"/>
    <result property="updatedAt" column="updated_at" jdbcType="TIMESTAMP"/>
</resultMap>

<sql id="Base_Column_List">
    id,name,description,price,created_at,updated_at
</sql>

<select id="selectProductByOrderId" resultMap="BaseResultMap">
    select p.id,p.name,p.description,p.price,p.created_at,p.updated_at
    from products p join order_items oi on p.id = oi.product_id
    where oi.order_id = #{orderId}
</select>

</mapper