MySQL是一個流行的開源關系型數據庫管理系統，它被廣泛用于構建各種類型的應用程序。創建一個MySQL系統包括以下步驟：

1. 下載并安裝MySQL

$ wget https://dev.mysql.com/get/mysql80-community-release-el7-3.noarch.rpm
$ sudo rpm -ivh mysql80-community-release-el7-3.noarch.rpm
$ sudo yum update
$ sudo yum install mysql-server
$ sudo systemctl start mysqld.service
$ sudo systemctl enable mysqld.service

2. 配置MySQL

$ sudo mysql_secure_installation

根據提示設置MySQL安全選項：

- Enter current password for root (enter for none): 回車
- Set root password: 輸入密碼
- Remove anonymous users? [Y/n]: Y
- Disallow root login remotely? [Y/n]: Y
- Remove test database and access to it? [Y/n]: Y
- Reload privilege tables now? [Y/n]: Y

3. 創建數據庫和表

$ mysql -u root -p
mysql>CREATE DATABASE mydatabase;
mysql>USE mydatabase;
mysql>CREATE TABLE mytable (
id INT NOT NULL AUTO_INCREMENT,
name VARCHAR(50),
age INT,
PRIMARY KEY (id)
);

4. 插入數據

mysql>INSERT INTO mytable (name, age)
VALUES ('John', 25);
mysql>INSERT INTO mytable (name, age)
VALUES ('Sarah', 30);
mysql>SELECT * FROM mytable;

以上步驟是創建MySQL系統的基本內容，根據實際需要可以對數據庫和表進行進一步配置和優化。