ubuntu(virtual box)にMySQLをインストールしてみた

参照サイト
https://www.digitalocean.com/community/tutorials/how-to-install-mysql-on-ubuntu-20-04-ja
https://qiita.com/houtarou/items/a44ce783d09201fc28f5
https://charlie1012.hatenablog.jp/entry/2015/09/05/170000
https://www.javadrive.jp/mysql/insert/index1.html

インストール・設定

MySQLをインストール

terminal

sudo apt update
sudo apt install mysql-server mysql-client

セキュリティスクリプトを実行する

terminal

sudo mysql_secure_installation

mysql_secure_installation

Securing the MySQL server deployment.

Connecting to MySQL using a blank password.

VALIDATE PASSWORD COMPONENT can be used to test passwords
and improve security. It checks the strength of password
and allows the users to set only those passwords which are
secure enough. Would you like to setup VALIDATE PASSWORD component?

Press y|Y for Yes, any other key for No: y

• パスワードの強度チェックをするか選択

mysql_secure_installation

There are three levels of password validation policy:

LOW    Length >= 8
MEDIUM Length >= 8, numeric, mixed case, and special characters
STRONG Length >= 8, numeric, mixed case, special characters and dictionary                  file

Please enter 0 = LOW, 1 = MEDIUM and 2 = STRONG: 0

• パスワード強度を選択する

mysql_secure_installation

Skipping password set for root as authentication with auth_socket is used by default.
If you would like to use password authentication instead, this can be done with the "ALTER_USER" command.
See https://dev.mysql.com/doc/refman/8.0/en/alter-user.html#alter-user-password-management for more information.

By default, a MySQL installation has an anonymous user,
allowing anyone to log into MySQL without having to have
a user account created for them. This is intended only for
testing, and to make the installation go a bit smoother.
You should remove them before moving into a production
environment.

Remove anonymous users? (Press y|Y for Yes, any other key for No) : y
Success.

• 匿名ユーザーを削除するか選択する

mysql_secure_installation

Normally, root should only be allowed to connect from
'localhost'. This ensures that someone cannot guess at
the root password from the network.

Disallow root login remotely? (Press y|Y for Yes, any other key for No) : y
Success.

• rootがリモートからログイン不可にするか選択する

mysql_secure_installation

By default, MySQL comes with a database named 'test' that
anyone can access. This is also intended only for testing,
and should be removed before moving into a production
environment.


Remove test database and access to it? (Press y|Y for Yes, any other key for No) : y
 - Dropping test database...
Success.

 - Removing privileges on test database...
Success.

• デフォルトでインストールされているテスト用DBとその権限を削除するか選択

mysql_secure_installation

Reloading the privilege tables will ensure that all changes
made so far will take effect immediately.

Reload privilege tables now? (Press y|Y for Yes, any other key for No) : y
Success.

All done! 

• このスクリプトの変更を即時に反映するか選択

MySQLを設定する

rootでログインする

terminal

sudo mysql -u root

rootのパスワードを設定する

terminal

ALTER USER 'root'@'localhost' IDENTIFIED BY '1';

データベースを作成する

terminal

CREATE DATABASE DB1;

ユーザーを作成・権限付与する

terminal

CREATE USER 'user'@'localhost' IDENTIFIED BY '1';
GRANT ALL ON DB1.* TO 'user'@'localhost';

rootをログアウトする

terminal

exit 

テーブルを作成する

作成したユーザーでログインする

terminal

sudo mysql -u user -p DB1;

テーブルを作成する

terminal

CREATE TABLE `addressBook` (
  `id` int(10) NOT NULL AUTO_INCREMENT,
  `name` varchar(255) NOT NULL,
  `age` int(3) NOT NULL,
  `address` varchar(255),
  PRIMARY KEY (`id`)
);

テーブルを確認する

terminal

SHOW TABLES;
+---------------+
| Tables_in_DB1 |
+---------------+
| addressBook   |
+---------------+
1 row in set (0.00 sec)


DESC addressBook;
+---------+--------------+------+-----+---------+----------------+
| Field   | Type         | Null | Key | Default | Extra          |
+---------+--------------+------+-----+---------+----------------+
| id      | int          | NO   | PRI | NULL    | auto_increment |
| name    | varchar(255) | NO   |     | NULL    |                |
| age     | int          | NO   |     | NULL    |                |
| address | varchar(255) | NO   |     | 　　    |                |
+---------+--------------+------+-----+---------+----------------+
4 rows in set (0.00 sec)

テーブルにデータを挿入する

INSERTを実行する

terminal

INSERT INTO addressBook 
(name,age,address)
VALUES  
('towamz', 20, 'Tokyo');

SELECTを実行する

terminal

SELECT * FROM addressBook;
+----+--------+-----+---------+
| id | name   | age | address |
+----+--------+-----+---------+
|  1 | towamz |  20 | Tokyo   |
+----+--------+-----+---------+
1 row in set (0.00 sec)