완성된 코드 해석하는방법

선생님이 수업페이지에 영상 찍어서 올려주셨으니 꼭 필독 할 것

코드를 해석할 수 있는 유일한 길라잡이임

롬복, toString, 클래스별 기능 분배, MVC, 등등

https://wiken.io/ken/12027

================이하 SQL LEFT JOIN 관련 내용================

DROP DATABASE IF EXISTS a6;

CREATE DATABASE a6;

USE a6;

CREATE TABLE student (
        id INT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY,
        `name` VARCHAR(100) NOT NULL
);

CREATE TABLE score (
    id INT UNSIGNED NOT NULL AUTO_INCREMENT PRIMARY KEY,
    student_id INT UNSIGNED NOT NULL,
    score INT NOT NULL,   
    FOREIGN KEY (student_id) REFERENCES student (id)
);

SELECT * FROM student;

SELECT * FROM score;

INSERT INTO student
SET `name` = '홍길동';

INSERT INTO student
SET `name` = '김철수';

INSERT INTO student
SET `name` = '김영희';

INSERT INTO student
SET `name` = '홍길순';

INSERT INTO student
SET `name` = '박대기';

INSERT INTO score
SET student_id = 1,
score = 20; 

INSERT INTO score
SET student_id = 3,
score = 30; 

INSERT INTO score
SET student_id = 5,
score = 40; 

SELECT student.id, AS `학생번호`, student.name AS `학생이름`, score.score AS `학생점수`
FROM score
INNER JOIN student;

SELECT 
student.id AS 학생번호,
student.name AS 학생이름,
score.score AS 학생점수
FROM student
LEFT JOIN score
ON student.id = score.student_id
ORDER BY 학생점수 DESC 
LIMIT 1;

DESC student;
DESC score;