多对多查询

<resultMap type="TUser" id="userRoleInfo" extends="BaseResultMap">
        <collection property="roles" ofType="TRole" columnPrefix="role_">
            <result column="id" property="id" />
            <result column="Name" property="roleName" />
            <result column="note" property="note" />
        </collection>
    </resultMap>
    
    
    <select id="selectUserRole" resultMap="userRoleInfo">
        select a.id, 
              a.user_name,
              a.real_name,
              a.sex,
              a.mobile,
              a.note,
              b.role_id,
              c.role_name,
              c.note role_note
        from t_user a,
             t_user_role b,
             t_role c
        where a.id = b.user_id AND 
              b.role_id = c.id
     </select>