【每日学习MyBaits基础】之关联查询

    public class Pro {
    private Integer id;

    private Integer contractDemandId;
    /**
     * 附件
     */
    private List<TdAttInfo> appendixData;
}

public class TdAttInfo {
    /**
     * pk 主键 自增
     */
    private Integer id;


    private Byte attachmentFromType;
}

<?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.xxx.xxx.xxx.xxxxProMapper">
  <resultMap id="BaseResultMap" type="com.xxx.xxx.entity.TdConDemPro">
    <id column="id" jdbcType="INTEGER" property="id" />
    <result column="contract_demand_id" jdbcType="INTEGER" property="contractDemandId" />
    <result column="engineering_name" jdbcType="VARCHAR" property="engineeringName" />
    <!-- 配置一对多的关系（图纸） -->
    <collection property="drawAttInfoList" ofType="TdAttInfo" 
			     select="getProDraws"
			     column="id">
    </collection>

  </resultMap>

  <!-- 获取工程对应图纸信息 -->
  <select id="getProDraws" parameterType="map" resultType="com.xxx.xxx.entity.TdAttInfo">
  		SELECT
			atta.id id,
			atta.attachment_name attachmentName,
		FROM
			td_attachment_info atta
		WHERE
			atta.attachment_from_type = 3
		AND atta.column_2 = 2
		AND atta.attachment_from_id = #{id}
  </select>
  <select id="方法" parameterType="int" resultMap="BaseResultMap">
  	SELECT
	dpro.id,
	dpro.contract_demand_id,
	FROM
	xxx_tab dpro
	WHERE dpro.id=#{id}
  </select>