mybatis中多表联合查询与DTO的字段对应问题

你把返回的字段映射到一个javabean里面，或者直接返回一个map，都可以。
引用文章地址：https://www.cnblogs.com/onlymate/p/4747227.html
https://blog.csdn.net/u012726702/article/details/72593547
单字段对应（没有对象外键和list）https://blog.csdn.net/vili_sky/article/details/73289962
附加：mybaits封装数据为map的方法：https://blog.csdn.net/m0_49194578/article/details/119378104?spm=1001.2101.3001.6650.1&utm_medium=distribute.pc_relevant.none-task-blog-2%7Edefault%7ECTRLIST%7Edefault-1.no_search_link&depth_1-utm_source=distribute.pc_relevant.none-task-blog-2%7Edefault%7ECTRLIST%7Edefault-1.no_search_link
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    SELECT
      u.id,
      u.username,
      u.password,
      r.id r_id,
      r.name r_name,
      r.jsms r_jsms,
      r.bz r_bz,
      r.jlzt r_jlzt,
      r.glbm r_glbm
    FROM
      user u
    LEFT JOIN
      role r
    ON
      u.id = r.userid


  id, username, password


    select
    
    from user
    where id = #{id,jdbcType=VARCHAR}


delete from user
where id = #{id,jdbcType=VARCHAR}


insert into user (id, username, password
  )
values (#{id,jdbcType=VARCHAR}, #{username,jdbcType=VARCHAR}, #{password,jdbcType=VARCHAR}
  )


    insert into user
    
        
            id,
        
        
            username,
        
        
            password,
        
    
    
        
            #{id,jdbcType=VARCHAR},
        
        
            #{username,jdbcType=VARCHAR},
        
        
            #{password,jdbcType=VARCHAR},
        
    


    update user
    
        
            username = #{username,jdbcType=VARCHAR},
        
        
            password = #{password,jdbcType=VARCHAR},
        
    
    where id = #{id,jdbcType=VARCHAR}


update user
set username = #{username,jdbcType=VARCHAR},
  password = #{password,jdbcType=VARCHAR}
where id = #{id,jdbcType=VARCHAR}

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