Mybatis关联查询结果集对象嵌套的具体使用 Mybatis关联查询结果集对象嵌套

在查询时经常出现一对多”的关系,所有会出现嵌套对象的情况，Mybatis在resultMap提供了collection标签，本文适合有一定Mybatis基础的读者查阅
数据模型WeixinActivity2018User.java

public class WeixinActivity2018Userimplements Serializable{/** serialVersionUID*/private static final long serialVersionUID = -2740162776768956231L; private int id; private String nickname; //昵称private String headurl; //头像private String openid; //微信用户OpenIdprivate String unionid; private String phone; //用户手机号private int count; //积攒数private String createtime; //创建时间private String uptime; //更新时间private List activity2018UserAssists; //点赞用户信息

【Mybatis关联查询结果集对象嵌套的具体使用】数据模型WeixinActivity2018UserAssist.java

public class WeixinActivity2018UserAssistimplements Serializable{/** serialVersionUID*/private static final long serialVersionUID = -2740162776768956232L; private int aid; private int uid; private String nickname; private String headurl; private String openid; private String unionid; private String createtime;

WeixinActivity2018UserMapper.xml

openid,unionid,phone,nickname,headurl,count,createtime,uptimeinsert into t_weixin_activity_2018_user (openid,unionid,phone,nickname,headurl,createtime,uptime)values (#{openid,jdbcType=VARCHAR},#{unionid,jdbcType=VARCHAR},#{phone,jdbcType=VARCHAR}, #{nickname,jdbcType=VARCHAR}, #{headurl,jdbcType=VARCHAR},now(),now())SELECTcount(twau.id)fromt_weixin_activity_2018_user twauand twau.openid = #{openid}and twau.id = #{id}and twau.phone = #{phone}SELECT twau.id,twau.openid, twau.unionid, twau.phone, twau.nickname, twau.headurl, twau.count,date_format( twau.createtime, '%Y-%m-%d %H:%m:%s') as createtime,date_format( twau.uptime, '%Y-%m-%d %H:%m:%s') as uptime,twaua.aid,twaua.uid,twaua.openid as aopenid,twaua.unionid as aunionid,twaua.nickname as anickname,twaua.headurl as aheadurl,date_format(twaua.createtime, '%Y-%m-%d %H:%m:%s') as acreatetime ,twaua.phone as aphonefromt_weixin_activity_2018_user twau LEFTJOIN t_weixin_activity_2018_user_assist twaua on twau.id=twaua.uidwhere 1=1and twau.openid = #{openid}and twau.id = #{id}and twau.phone = #{phone}order by tlb.createtime desc limit ${start}, ${number}