[생활코딩] 3일차 - 1. CRUD : Create

https://youtu.be/75LHpeOQiOs

 

CRUD

- Create, Read, Update, Delete

- Create, Read는 다 됨. Update, Delete는 안되는 경우도 있음

 

Read

SHOW DATABASES;
+--------------------+
| Database           |
+--------------------+
| information_schema |
| mysql              |
| opentutorials      |
| performance_schema |
| test               |
+--------------------+

db 보여줌

 

SHOW TABLES IN opentutorials;
+-------------------------+
| Tables_in_opentutorials |
+-------------------------+
| topic                   |
+-------------------------+

opentutorials라는 db에 어떤 table이 있는지 보여줌

 

DESC topic;
+-------------+--------------+------+-----+---------+----------------+
| Field       | Type         | Null | Key | Default | Extra          |
+-------------+--------------+------+-----+---------+----------------+
| id          | int(11)      | NO   | PRI | NULL    | auto_increment |
| title       | varchar(100) | NO   |     | NULL    |                |
| description | text         | YES  |     | NULL    |                |
| created     | datetime     | NO   |     | NULL    |                |
| author      | varchar(30)  | YES  |     | NULL    |                |
| profile     | varchar(100) | YES  |     | NULL    |                |
+-------------+--------------+------+-----+---------+----------------+

DESC : describe

topic이라는 table의 description

 

INSERT INTO topic (title, description, created, author, profile) VALUES ('MySQL', 'MySQL is ...', NOW(), 'egoing', 'developer');
SELECT * FROM topic;

id는 auto_increment에 의해서 자동으로 입력되기 때문에 따로 지정 X

열 이름과 값 순서대로 입력

 

topic이라는 table에서(from) 전체(*)를 선택해서(select) 보여줌

 

 

반복해서 입력

 

완성

SELECT * FROM topic;
+----+------------+-------------------+---------------------+--------+---------------------------+
| id | title      | description       | created             | author | profile                   |
+----+------------+-------------------+---------------------+--------+---------------------------+
|  1 | MySQL      | MySQL is ...      | 2022-04-17 19:27:40 | egoing | developer                 |
|  2 | ORACLEL    | ORACLEL is ...    | 2022-04-17 19:29:30 | egoing | developer                 |
|  3 | SQL Server | SQL Server is ... | 2022-04-17 19:43:49 | duru   | data administrator        |
|  4 | PostgreSQL | PostgreSQL is ... | 2022-04-17 19:44:56 | taeho  | data scientist, developer |
|  5 | MongoDB    | MongoDB is ...    | 2022-04-17 19:45:47 | egoing | developer                 |
+----+------------+-------------------+---------------------+--------+---------------------------+

 

No database selected 에러

USE opentutorials;