seolhee

MySQL은 오픈 소스 관계형 데이터베이스 관리 시스템(RDBMS)입니다.

MySQL은 다중 사용자, 다중 스레드 RDBMS로서, 데이터의 안정성과 보안성을 제공합니다. MySQL은 대부분의 운영 체제에서 작동하며, 웹 애플리케이션 개발, 데이터 분석, 빅 데이터, 클라우드 기반 애플리케이션 등에 많이 사용됩니다.

MySQL은 SQL(Structured Query Language)을 사용하여 데이터를 관리합니다. SQL은 데이터베이스에 저장된 데이터를 조작하기 위한 표준적인 언어로서, 데이터를 검색, 삽입, 업데이트, 삭제하는데 사용됩니다. MySQL은 이러한 SQL 문을 이용하여 데이터를 쿼리하고, 데이터의 무결성을 유지하며, 데이터베이스를 관리합니다.

MySQL은 사용이 간편하며, 대용량 데이터베이스를 처리할 수 있는 고성능 기능을 제공합니다. 또한, 오픈 소스로서, 다양한 개발자들이 지속적으로 개발 및 유지보수하고 있어, 사용자들이 다양한 문제들을 해결할 수 있는 방법을 제공합니다.

MySQL은 PHP 스크립트 언어와 상호 연동이 잘 되면서 오픈소스로 개발된 무료 프로그램입니다. 그래서 홈페이지나 쇼핑몰(워드프레스,Cafe24, 그누보드, 제로보드 등)에 가장 일반적으로 웹 개발에 멀리 사용하고 있습니다.

🧡 MySQL설치

MAMP란 웹사이트를 개발할 때 쓰이는 기술 스택인 macOS, Apache, MySQL, PHP의 약어이자 솔루션 스택이다.
https://www.mamp.info/en/downloads/

php 정보 확인

phpinfo();

정보 파일 수정 위치: Loaded Configuration File : C:\MAMP\conf\php8.0.1\php.ini

에러 표시 : display_errors = On

캐시 설정 : opcache.enable = 0

PHP 관리자 페이지 : http://localhost/phpMyAdmin/

💛 MySQL 실행

윈도우 : cd MAMP/bin/mysql/bin(cd c:\MAMP\bin\mysql\bin)
로그인 : mysql -uroot -proot

Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 3
Server version: 5.7.24 MySQL Community Server (GPL)

Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

맥 : sd /Applications/MAMP/Library/bin
로그인 : ./mysql -uroot -proot

show databases;

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| sys                |
+--------------------+
4 rows in set (0.00 sec)

create database 데이터베이스 이름;

mysql> create database sample01;
Query OK, 1 row affected (0.00 sec)

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| sample01           |
| sys                |
+--------------------+
5 rows in set (0.00 sec)

use 데이터베이스 이름;

mysql> use sample01;
Database changed

drop database 데이터베이스 이름;

drop database sample01;
Query OK, 0 row affected (0.00 sec)

mysql> show databases;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| performance_schema |
| sys                |
+--------------------+
4 rows in set (0.00 sec)

create table 테이블 이름;

create table members(
    memberID int(10) unsigned auto_increment,
    youEmail varchar(40) NOT NULL,
    youName varchar(10) NOT NULL,
    youPass varchar(20) NOT NULL,
    youBirth int(10) NOT NULL,
    youAge int(5) NOT NULL,
    regTime int(30) NOT NULL,
    PRIMARY KEY(memberID)
) charset=utf8;

create table reviews(
    reviewID int(10) unsigned auto_increment,
    memberID int(10) unsigned,
    youText tinytext NOT NULL,
    regTime int(30) NOT NULL,
    PRIMARY KEY(reviewID)
) charset=utf8;

show tables;

mysql> show tables;
+--------------------+
| Tables_in_sample01 |
+--------------------+
| member             |
+--------------------+
1 row in set (0.00 sec)

desc 테이블 이름;

mysql> desc member;
+------------+------------------+------+-----+---------+----------------+
| Field      | Type             | Null | Key | Default | Extra          |
+------------+------------------+------+-----+---------+----------------+
| MemberID   | int(10) unsigned | NO   | PRI | NULL    | auto_increment |
| youEmail   | varchar(40)      | NO   |     | NULL    |                |
| youName    | varchar(20)      | NO   |     | NULL    |                |
| youPass    | varchar(20)      | NO   |     | NULL    |                |
| youBirth   | int(20)          | NO   |     | NULL    |                |
| youAge     | int(5)           | NO   |     | NULL    |                |
| regTime    | int(20)          | NO   |     | NULL    |                |
+------------+------------------+------+-----+---------+----------------+
7 rows in set (0.01 sec)

drop table 테이블 이름;

mysql> drop table members;
Query OK, 0 rows affected (0.01 sec)

truncate table 테이블 이름;

mysql> truncate table members;
Query OK, 0 rows affected (0.01 sec)

INSERT INTO 테이블명(필드명) VALUES

INSERT INTO members(youEmail, youName, youPass, youBirth, youAge, regTime) VALUES("메일","이름","비번","생년월일","나이","등록시간");

INSERT INTO members(youEmail, youName, youPass, youBirth, youAge, regTime) VALUES("webstoryboy@naver.com","황상연","1234","19990304","26","03140316");
INSERT INTO members(youEmail, youName, youPass, youBirth, youAge, regTime) VALUES("dlscks0930@naver.com","황인찬","1234","19980930","26","03140316");
INSERT INTO members(youEmail, youName, youPass, youBirth, youAge, regTime) VALUES("gp2617@naver.com","천설희","1234","19950313","29","03140316");
INSERT INTO members(youEmail, youName, youPass, youBirth, youAge, regTime) VALUES("dsy1943@naver.com","여다슬","1943","20011227","23","03140316");
INSERT INTO members(youEmail, youName, youPass, youBirth, youAge, regTime) VALUES("1346zany@gmail.com","이승연","1234","19991216","25","03140316");
INSERT INTO members(youEmail, youName, youPass, youBirth, youAge, regTime) VALUES("ebmdols@naver.com","장진용","1234","19940401","26","03140316");
INSERT INTO members(youEmail, youName, youpass, youBirth, youAge, regTime) VALUES("jo0132@naver.com","노지영","1234","19950323","29","03140316");
INSERT INTO members(youEmail, youName, youPass, youBirth, youAge, regTime) VALUES("skadldldl123@gmail.com","안교남","1234","19920923","32","03140316");
INSERT INTO members(youEmail, youName, youPass, youBirth, youAge, regTime) VALUES("ehcjswo1@gmail.com","김도현","123","19951003","29","03140316");
INSERT INTO members(youEmail, youName, youPass, youBirth, youAge, regTime) VALUES("goed0522@gmail.com","변우현","1234","20000629","24","03141516");
INSERT INTO members(youEmail, youName, youPass, youBirth, youAge, regTime) VALUES("yuna243441@naver.com","이유나","1234","20020508","22","03140316");
INSERT INTO members(youEmail, youName, youPass, youBirth, youAge, regTime) VALUES("im.kebab00@gmail.com","이요셉","1234","19990315","26","03140316");
INSERT INTO members(youEmail, youName, youpass, youBirth, youAge, regTime) VALUES("ture403@gmail.com","전윤기","1234","19920210","32","03140316");
INSERT INTO members(youEmail, youName, youPass, youBirth, youAge, regTime) VALUES("dongjin6539@naver.com","신동진","1234","19960709","28","03140316");
INSERT INTO members(youEmail, youName, youPass, youBirth, youAge, regTime) VALUES("gnsrbdi@naver.com","이훈규","1234","19950227","29","03140316");
INSERT INTO members(youEmail, youName, youPass, youBirth, youAge, regTime) VALUES("jeongyouna_@naver.com","정유나","1234","19950606","29","03140316");
INSERT INTO members(youEmail, youName, youPass, youBirth, youAge, regTime) VALUES("daanbi1345@gmail.com","조은경","1234","19930205","31","03140316");
INSERT INTO members(youEmail, youName, youPass, youBirth, youAge, regTime) VALUES("hunmi961119@gmail.com","진현미","1234","19961119","28","03140316");
INSERT INTO members(youEmail, youName, youPass, youBirth, youAge, regTime) VALUES("getgrovy@gmail.com","정희석","1234","19990101","26","03140316");
INSERT INTO members(youEmail, youName, youPass, youBirth, youAge, regTime) VALUES("kshkmn0929@naver.com","김도현","0929","20020929","22","03140316");
INSERT INTO members(youEmail, youName, youPass, youBirth, youAge, regTime) VALUES("hyejeong3283@gmail.com","이혜정","1234","19940622","30","03140316");
INSERT INTO members(youEmail, youName, youPass, youBirth, youAge, regTime) VALUES("didrn94553@gmail.com","이양구","1234","19941212","30","03140316");
INSERT INTO members(youEmail, youName, youPass, youBirth, youAge, regTime) VALUES("ghkddn132@naver.com","정황우","1234","19970130","25","03140316");
INSERT INTO members(youEmail, youName, youPass, youBirth, youAge, regTime) VALUES("esansi@naver.com","김현빈","1234","19970524","27","03140316");
INSERT INTO members(youEmail, youName, youPass, youBirth, youAge, regTime) VALUES("lee3ll@naver.com","이은지","1234","19930311","31","03140316");
INSERT INTO members(youEmail, youName, youPass, youBirth, youAge, regTime) VALUES("dripidea77@gmail.com","김시연","1234","19930313","31","03140316");
INSERT INTO members(youEmail, youName, youPass, youBirth, youAge, regTime) VALUES("itshena01@gmail.com","조한미","1234","19930211","31","03140316");
INSERT INTO members(youEmail, youName, youPass, youBirth, youAge, regTime) VALUES("aimee00418@gmail.com","권현정","1234","19830211","39","03140316");


INSERT INTO reviews(memberID, youText, regTime) VALUES("4", "정말 감사합니다. 잘 봤어요!", "1234567");
INSERT INTO reviews(memberID, youText, regTime) VALUES("14", "항상 감사합니다~", "7675");
INSERT INTO reviews(memberID, youText, regTime) VALUES("2", "진짜 감사합니다. 또 올게요!", "2676");
INSERT INTO reviews(memberID, youText, regTime) VALUES("5", "완전 감사합니다~ 잘 봤어요~", "87574");
INSERT INTO reviews(memberID, youText, regTime) VALUES("7", "굿. 잘 봤어요", "2456");
INSERT INTO reviews(memberID, youText, regTime) VALUES("1", "완벽합니당. 잘 봤어요", "86745");
INSERT INTO reviews(memberID, youText, regTime) VALUES("9", "내용이 깔끔합니다. 잘 봤어요", "87967954");
INSERT INTO reviews(memberID, youText, regTime) VALUES("8", "좋은 정보 감사합니다. 잘 봤어요", "234256");
INSERT INTO reviews(memberID, youText, regTime) VALUES("2", "정리 깔끔하게 잘하셨네요. 잘 봤어요", "869696");
INSERT INTO reviews(memberID, youText, regTime) VALUES("7", "웩.", "36356547");

SELECT 필드명 FROM 테이블명 WHERE 조건

전체 데이터 불러오기

SELECT * FROM member;

이름 내림차순으로 불러오기

SELECT * FROM member ORDER BY youName DESC;

이름 올림차순으로 불러오기

SELECT * FROM member ORDER BY youName ASC;

memberID가 1번인 경우만 불러오기

SELECT * FROM member WHERE memberID = 1;

memberID가 1번이 아닌 경우만 불러오기

SELECT * FROM member WHERE memberID <> 1;

memberID가 5번~10번 경우만 불러오기

SELECT * FROM member WHERE memberID >=5 AND memberID <= 10;

youAge가 30~40 경우만 불러오기

SELECT * FROM member WHERE youAge BETWEEN 30 AND 40;

youAge가 30~40 아닌 경우만 불러오기

SELECT * FROM member WHERE youAge NOT BETWEEN 30 AND 40;

memberID가 1, 5, 10, 15번만 경우만 불러오기

SELECT * FROM member WHERE memberID IN(1,5,10,15);

youName 중에 데이터가 없는 것 불러오기

SELECT * FROM member WHERE youName IS NULL;

youName 중에 데이터가 없는 것 반대 불러오기

SELECT * FROM member WHERE youName IS NOT NULL;

youName 중에 "연" 텍스트가 포함된 이름 불러오기

SELECT * FROM member WHERE youName LIKE '%연%';

youName 중에 "김"으로 시작하는 이름 불러오기

SELECT * FROM member WHERE youName LIKE '김%';

youName 중에 "현"으로 끝나는 이름 불러오기

SELECT * FROM member WHERE youName LIKE '%현';

youName 중에 "상"이 들어가는 이름 불러오기

SELECT * FROM member WHERE youName LIKE '_상_';

youName 중에 "김" 또는 "이" 이 들어가는 이름 불러오기

SELECT * FROM member WHERE youName LIKE '김%' OR youName LIKE '이%';

이름만 불러오기

SELECT youName FROM member;

이름만 불러오기(올림차순)

SELECT youName FROM member ORDER BY youName ASC;

이름만 불러오기(내림차순)

SELECT youName FROM member ORDER BY youName DESC;

이름과 나이 불러오기

SELECT youName, youAge FROM member;

이름과 나이(30세 이상)만 불러오기

SELECT youName, youAge FROM member WHERE youAge >= 30;

나이가 25이상이면서 김씨 성을 갖고 있는 사람 이름 불러오기

SELECT youName FROM member WHERE youName LIKE '김__' AND youAge >=25;

나이가 25이상이고 김씨 성을 갖고 있는 사람 이름 불러오기

SELECT youName FROM member WHERE youName LIKE '김__' OR youAge >=25;

나이가 25이상이고 아이디가 2 또는 아이디가 9인 멤버 불러오기

SELECT * FROM member WHERE (memberID = 2 OR memberID = 9) AND youAge >= 25;
SELECT * FROM member WHERE youAge >= 25 AND memberID IN(2, 9);

회원 데이터를 5개만 불러오기 (1-5)

SELECT * FROM member LIMIT 5;

회원 데이터를 5개만 불러오기 (6-10)

SELECT * FROM member LIMIT 5, 5;

회원 이메일을 기준으로 10개만 불러오기 (11-20)

SELECT youEmail FROM member LIMIT 10, 10;

중복된 나이 제거하기

SELECT DISTINCT youAge FROM member;

생일이 3월인 사람 이름 불러오기

SELECT youName FROM member WHERE youBirth LIKE '____03__';

이름 갯수 불러오기

SELECT count(youName) FROM member;
SELECT count(*) FROM member;

UPDATE 테이블명 SET 컬럼명 조건

모든 회원의 비밀번호를 1234로 수정하기

UPDATE member SET youPass = "1234";

아이디가 3번인 회원만 비밀번호 9999로 수정하기

UPDATE member SET youPass = "9999" WHERE memberID = 3;

아이디가 5-10번인 회원의 비밀번호를 7777로 수정하기

UPDATE member SET youPass = "7777" WHERE memberID BETWEEN 5 AND 10;

1번부터 10번까지 나이를 50으로 수정하기

UPDATE member SET youAge = "50" WHERE memberID BETWEEN 1 AND 10;

DELETEFROM 테이블명 WHERE 조건

아이디가 5번인 멤버 삭제하기

DELETE FROM member WHERE memberID = 5;

회원 비밀번호가 1234인 사람만 삭제하기

DELETE FROM member WHERE youPass = 1234;

memberID를 기준으로 5번째 멤버까지 삭제

DELETE FROM member ORDER BY memberID LIMIT 5;

memberID를 기준으로 11, 13, 15 멤버 삭제

DELETE FROM member WHERE memberID IN(11, 13, 15);

ALTER TABLE [테이블명] ADD [추가할 필드명 AFTER [필드 위치]

멤버 테이블에 핸드폰 번호 필드를 추가

ALTER TABLE members ADD youPhone varchar(20) NOT NULL;

멤버 테이블에 핸드폰 번호 필드를 youAge 뒤에 추가

ALTER TABLE members ADD youphone varchar(20) NOT NULL AFTER youAge;

ALTER TABLE [테이블명] MODIFY [수정할 필드명]

ALTER TABLE members MODIFY youPhone int(20) NOT NULL;

int(20)를 varchar(20)로 수정

ALTER TABLE members MODIFY youPhone varchar(20);

ALTER TABLE [테이블명] DROP [삭제할 필드명]

ALTER TABLE members DROP youPhone;

SELECT [필드명] FROM [테이블명 앨리어스] JOIN [연결할 테이블명 앨리어스] ON [기준이 되는 조건문]

두개의 테이블(members, review) 합치기

SELECT m.youEmail, m.youName, r.youText, r.regTime FROM members m JOIN reviews r ON (m.memberID = r.memberID);

두개의 테이블(members, review) 합치기 : 필드명 변경하기(AS)

SELECT m.youEmail, m.youName, r.youText, r.regTime AS reviewRegTime FROM members m JOIN reviews r ON (m.memberID = r.memberID);

두개의 테이블(members, review) 합치기 : 왼쪽 테이블 기준

SELECT m.youEmail, m.youName, r.youText, r.regTime FROM members m LEFT JOIN reviews r ON (m.memberID = r.memberID);

CREATE TABLE schoolRecode (
    studentID int(10) unsigned NOT NULL AUTO_INCREMENT comment "학생번호",
    class tinytext comment "소속클래스(반)",
    english tinytext NOT NULL comment "영어점수",
    math tinytext NOT NULL comment "수학점수",
    science tinytext NOT NULL comment "과학점수",
    coding tinytext NOT NULL comment "코딩점수",
    PRIMARY KEY(studentID)
) charset=utf8;

INSERT INTO schoolRecode(english, math, science, coding) VALUES(50, 10, 20, 100);
INSERT INTO schoolRecode(class, english, math, science, coding) VALUES(1, 50, 10, 20, 100);
INSERT INTO schoolRecode(class, english, math, science, coding) VALUES(2, 40, 30, 22, 90);
INSERT INTO schoolRecode(class, english, math, science, coding) VALUES(2, 50, 40, 23, 80);
INSERT INTO schoolRecode(class, english, math, science, coding) VALUES(3, 60, 50, 24, 70);
INSERT INTO schoolRecode(class, english, math, science, coding) VALUES(4, 70, 60, 25, 60);
INSERT INTO schoolRecode(class, english, math, science, coding) VALUES(5, 80, 70, 26, 50);

레코드 갯수 구하기

SELECT count(class) FROM schoolRecode;

레코드 갯수(NULL 값 포함) 구하기

SELECT count(*) FROM schoolRecode;

레코드 합계 구하기

SELECT sum(coding) FROM schoolRecode;

코딩 합계 구하기 (학생 아이디가 1~4)

SELECT sum(coding) FROM schoolRecode WHERE studentID >=1 AND studentID <=4;

가장 높은 코딩 점수 구하기

SELECT max(coding) FROM schoolRecode;

가장 낮은 코딩 점수 구하기

SELECT min(coding) FROM schoolRecode;

코딩 점수 평균 구하기

SELECT avg(coding) FROM schoolRecode;

💝그룹별 집계

SELECT [필드명] FROM [테이블명] GROUP BY [필드명]

반별로 학생들의 영어 점수 평균값 구하기

SELECT class, avg(english) FROM schoolRecode WHERE class IN(1,2,3,4,5) GROUP BY class;

반별로 학생들의 수학 점수 합계 구하기

SELECT class, sum(math) FROM schoolRecode WHERE class IN(1,2,3,4,5) GROUP BY class;

학생들의 수학 점수 합계 점수가 70점 이상인 반

SELECT class, sum(math) FROM schoolRecode WHERE class IN(1,2,3,4,5) GROUP BY class HAVING sum(math) >= 70;

❣️출력 결과의 정렬

SELECT [필드명] FROM [테이블명] ORDER BY [필드명] DESC 또는 ASC

영어 점수를 높은 순에서 낮은 순으로 표시

SELECT studentID, english FROM schoolRecode ORDER BY english DESC;

영어 점수를 낮은 순에서 높은 순으로 표시

SELECT studentID, english FROM schoolRecode ORDER BY english ASC;

반별로 수학 점수를 높은 순에서 낮은 순으로 표시

SELECT class, sum(math) FROM schoolRecode WHERE class IN(1,2,3,4,5) GROUP BY class ORDER BY sum(math) DESC;

MySQL