forest/src/main/java/mapper/UserExtendMapper.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.rymcu.forest.mapper.UserExtendMapper">
    <resultMap id="BaseResultMap" type="com.rymcu.forest.entity.UserExtend">
        <result column="id_user" property="idUser"></result>
        <result column="github" property="github"></result>
        <result column="weibo" property="weibo"></result>
        <result column="weixin" property="weixin"></result>
        <result column="qq" property="qq"></result>
        <result column="blog" property="blog"></result>
    </resultMap>
    <select id="selectUserExtendByNickname" resultMap="BaseResultMap">
        select vue.* from forest_user_extend vue join forest_user vu on vue.id_user = vu.id
        where vu.nickname = #{nickname} limit 1
    </select>
</mapper>