First we’ll login to the MySQL server from the command line with the following command:
mysql -u root -p
In this case, I’ve specified the user root with the -u flag, and then used the -p flag so MySQL prompts for a password. Enter your current password to complete the login.
If you need to change your root (or any other) password in the database, then please do so first!
You should now be at a MySQL prompt that looks very similar to this:
View a List of MySQL Users
Viewing a full list of MySQL users, including the host they’re associated with, can be done with the following select statement:
SELECT User,Host FROM mysql.user;
Remove a MySQL User
To remove a user from MySQL, we again use the DROP command.
It only takes one simple command to delete a user in MySQL, but BEWARE; dropping a user can not be undone! The command is as follows:
DROP USER 'testuser'@'localhost';
If a user of the name testuser does not exist, then you’ll receive this error:
ERROR 1396 (HY000): Operation DROP USER failed for 'testuser'@'localhost'
Refer to the View a List of MySQL Users section above if you receive the above error, and double check the username and host.