industry-data-platform/industry-system/industry-da/src/main/resources/mapper/SystemDao.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.example.opc_da.dao.SystemDao">

    <insert id="addCode">
        insert into sys_register_code(register_code, create_time)
            value (#{code},now())
    </insert>
    <update id="clearCode">
        TRUNCATE TABLE sys_register_code
    </update>


    <select id="getCode" resultType="java.lang.String">
        select register_code
        from sys_register_code limit 1
    </select>
</mapper>