如果你正在使用MySQL數據庫，當你啟動MySQL時，出現"mysql請求服務已啟動"的提示信息，表明你已經成功地啟動了MySQL服務。

[root@localhost ~]# systemctl start mysqld.service
[root@localhost ~]# systemctl status mysqld.service
● mysqld.service - MySQL Server
Loaded: loaded (/usr/lib/systemd/system/mysqld.service; disabled; vendor preset: disabled)
Active: active (running) since Wed 2022-06-15 17:26:12 CST; 1s ago
Process: 3864 ExecStartPost=/usr/bin/mysql-systemd-start post (code=exited, status=0/SUCCESS)
Process: 3815 ExecStartPre=/usr/bin/mysql-systemd-start pre (code=exited, status=0/SUCCESS)
 Main PID: 3863 (mysqld_safe)
CGroup: /system.slice/mysqld.service
├─3863 /bin/sh /usr/bin/mysqld_safe --basedir=/usr
└─3987 /usr/sbin/mysqld --basedir=/usr --datadir=/var/lib/my...
Jun 15 17:26:10 localhost.localdomain systemd[1]: Starting MySQL Server...
Jun 15 17:26:10 localhost.localdomain mysqld_safe[3863]: 2022-06-15T09:...:0
Jun 15 17:26:10 localhost.localdomain mysqld_safe[3863]: 2022-06-15T09:...:0
Jun 15 17:26:12 localhost.localdomain systemd[1]: Started MySQL Server.

以上是在Linux系統下啟動MySQL服務的過程，使用systemctl命令可以管理和控制服務。