kmall-pt/kmall-api/src/main/resources/mybatis/mapper/ApiSysConfigMapper.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.kmall.api.dao.ApiSysConfigMapper">
	<!-- 根据key，查询value -->
	<select id="queryByKey" parameterType="string" resultType="string">
		select value from sys_config where `key` = #{key}
	</select>

	<!-- 根据key，更新value -->
	<update id="updateValueByKey" parameterType="map">
		update sys_config set `value` = #{value} where `key` = #{key}
	</update>
</mapper>