How to set root password to null

Worked for me and "5.7.11 MySQL Community Server":

use mysql;
update user set authentication_string=password(''), plugin='mysql_native_password' where user='root';

I had to change the 'plugin' field as well because it was set to 'auth_socket'.

After that I could connect as mysql -u root without a password.

If you want an empty password, you should set the password to null and not use the Password hash function, as such:

On the command line:

sudo service mysql stop
sudo mysqld_safe --skip-grant-tables --skip-networking &
mysql -uroot

In MySQL:

use mysql;
update user set password=null where User='root';
flush privileges;
quit;

• connect to mysql as user root (use one of the two following methods)
  • login as root and start mysql using mysql -p, enter current root password
  • login as self and start mysql using mysql -u root -p, enter current root password
• mysql> set password = password('');

Done! No root password.

SET PASSWORD FOR 'root'@'localhost' = PASSWORD('');

This worked for me on Ubuntu 16.04 with v5.7.15 MySQL:

First, make sure you have mysql-client installed (sudo apt-get install mysql-client).

Open terminal and login:

mysql -uroot -p

(then type your password)

After that:

use mysql;
update user set authentication_string=password(''), plugin='mysql_native_password' where user='root';

(tnx @Stanislav Karakhanov)

And the very last important thing is to reset mysql service:

sudo service mysql restart

You should now be able to login (without passsword) also by using MySQL Workbench.