Obsidian-Main/04. Programming/DB/MySQL.md

Install MySQL

• 下載MySQL： https://downloads.mysql.com/archives/installer/
• 安裝
• 安裝之後，執行MSQL Installer - Community
  • !
• 選擇MySQL Server的Reconfigure
  • !
• 依序設定port、帳號密碼。

Install MariaDB

1. sudo apt install mariadb-server
2. Configuring MariaDB: sudo mysql_secure_installation 這步驟會問幾個問題，大概是： 1.　輸入目前root的密碼 2.　是否要切換為unix_socket？ -> No 3.　要變更root的密碼嗎？-> No
3. Testing MariaDB: sudo systemctl status mariadb
4. Show version: sudo mysqladmin version

Syntax

Basic

login as root: mysql -u root -p

User management

Create user

CREATE USER 'testuser'@'localhost' IDENTIFIED BY 'test123test!';

Remove user

DROP USER 'testuser'@'localhost';

Grant user's permission

Below commands grant user's permission to CREATE and DROP.

GRANT CREATE ON *.* TO 'testuser'@'localhost';
GRANT DROP ON tutorial_database.* TO 'testuser'@'localhost';
FLUSH PRIVILEGES;

Remove user's permission

REVOKE <permission> ON database.table FROM 'user'@'localhost';

上面命令中的<permission>必須替換成下面的其中一個：

• ALL - Allow complete access to a specific database. If a database is not specified, then allow complete access to the entirety of MySQL.
• CREATE - Allow a user to create databases and tables.
• DELETE - Allow a user to delete rows from a table.
• DROP - Allow a user to drop databases and tables.
• EXECUTE - Allow a user to execute stored routines.
• GRANT OPTION - Allow a user to grant or remove another user's privileges.
• INSERT - Allow a user to insert rows from a table.
• SELECT - Allow a user to select data from a database.
• SHOW DATABASES- Allow a user to view a list of all databases.
• UPDATE - Allow a user to update rows in a table.

例如：REVOKE CREATE ON *.* FROM 'testuser'@'localhost'; 最後，不要忘記FLUSH PRIVILEGES;

Show user's permission

SHOW GRANTS FOR 'testuser'@'localhost';

Change user's password

ALTER USER 'user-name'@'localhost' IDENTIFIED BY 'NEW_USER_PASSWORD';

View all users

SELECT User,Host FROM mysql.user;

Database

Show all databases

SHOW DATABASES;

Create table

The rule:

CREATE TABLE table_name (column_name column_type);

Example:

CREATE TABLE tutorials_tbl(
   tutorial_id INT NOT NULL AUTO_INCREMENT,
   tutorial_title VARCHAR(100) NOT NULL,
   tutorial_author VARCHAR(40) NOT NULL,
   submission_date DATE,
   PRIMARY KEY ( tutorial_id )
);

use autostation;
CREATE TABLE station_state(
   id CHAR(255) NOT NULL,
   ip CHAR(255) NOT NULL,
   dhcp_ip CHAR(255) NOT NULL,
   name CHAR(255) NOT NULL,
   setupfilemd5 CHAR(255) NOT NULL,
   setupfileversion CHAR(255) NOT NULL,
   status CHAR(255) NOT NULL,
   update_time DATETIME NOT NULL,
   PRIMARY KEY ( id )
);

Insert

The rule:

INSERT INTO <table_name> ( field1, field2,...fieldN )
                         VALUES
                         ( value1, value2,...valueN );

Example:

INSERT INTO client_state ( field1, field2,...fieldN )
                         VALUES
                         ( value1, value2,...valueN );

參考

-　Create a MySQL User on Linux via Command Line | Liquid Web -　Grant Permissions to a MySQL User on Linux via Command Line | Liquid Web -　Remove Permissions for a MySQL User on Linux via Command Line - Liquid Web -　Remove a MySQL User on Linux via Command Line - Liquid Web