Assuming you have mySQL or MariaDB installed on a Linux system, the which command can be used to determine if the mysql command line tool is installed. In this example, the mysql command line tool is installed.

~]# which mysql
/bin/mysql

The mysql command with the -V or --version flag can be used to determine the version of mySQL or MariaDB that is installed.

~]# mysql --version
mysql  Ver 14.14 Distrib 5.7.33, for Linux (x86_64) using  EditLine wrapper

Or like this.

~]# mysql -e "select @@version"
+-----------------+
| @@version       |
+-----------------+
| 10.5.10-MariaDB |
+-----------------+