MySql is a relational Database Management System.
Use ?"Synaptic" to install program if you don't have the packages installed.
MySql Server
MySql can start on boot time or only if you type manually (as root):
/etc/init.d/mysql start
After an upgrade of the Debian package you might need to run (as root):
mysql_fix_privilege_tables.
MySql will only install if you have a NON-NUMERIC hostname that is resolvable via the /etc/host file
The Debian package of ["MySQL"] server creates the user debian-sys-maint that is used in the start-stop and cron ["script"]s. Don't delete him.
MySql Client
Ty use ["MySQL"] client just type as any user : mysql
You can use too ["MySQL"] Navigator typing
mysql-navigator
in a terminal ( the package name is the same to get it using apt or ["Synaptic"]).
After installation, you can find it in the Debian / Database menu too.
You can use too MySql Control Center and gmyclient.