lineage/ruoyi-system/src/main/resources/mapper/app/TbMyFriendsMapper.xml

<?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.ruoyi.app.mapper.TbMyFriendsMapper">
    
    <resultMap type="TbMyFriends" id="TbMyFriendsResult">
        <result property="id"    column="id"    />
        <result property="appUserId"    column="app_user_id"    />
        <result property="friendsUserId"    column="friends_user_id"    />
        <result property="status"    column="status"    />
        <result property="createBy"    column="create_by"    />
        <result property="createTime"    column="create_time"    />
        <result property="updateBy"    column="update_by"    />
        <result property="updateTime"    column="update_time"    />
        <result property="remark"    column="remark"    />
    </resultMap>

    <sql id="friendsSql">

    </sql>

    <select id="listFriends" resultType="com.ruoyi.app.domain.TbMyFriends" parameterType="String">
        select * from (
        select f.*,(select u.nick_name from tb_app_user u where f.app_user_id = u.id) nick_name
        from tb_my_friends f where friends_user_id = #{id}
        union all
        select g.*,(select u.nick_name from tb_app_user u where g.friends_user_id = u.id) nick_name
        from tb_my_friends g  where app_user_id = #{id}
        ) a where 1=1
        <if test="status != null and status != '' ">
           and a.status = #{status}
        </if>
        <if test="nickName != null and nickName != '' ">
            and a.nick_name like concat('%',#{nickName},'%')
        </if>
    </select>

</mapper>