참조 : https://mybatis.org/mybatis-3/configuration.html
XML File 클릭 후 아래 코드 추가
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN" "https://mybatis.org/dtd/mybatis-3-mapper.dtd"> <mapper namespace=""> </mapper>